CINXE.COM

<!DOCTYPE html> <html class="client-nojs vector-feature-language-in-header-enabled vector-feature-language-in-main-page-header-disabled vector-feature-sticky-header-disabled vector-feature-page-tools-pinned-disabled vector-feature-toc-pinned-clientpref-1 vector-feature-main-menu-pinned-disabled vector-feature-limited-width-clientpref-1 vector-feature-limited-width-content-enabled vector-feature-custom-font-size-clientpref-1 vector-feature-appearance-pinned-clientpref-1 vector-feature-night-mode-enabled skin-theme-clientpref-day vector-toc-available" lang="en" dir="ltr"> <head> <meta charset="UTF-8"> <title>Rebreather diving - Wikipedia</title> <script>(function(){var className="client-js vector-feature-language-in-header-enabled vector-feature-language-in-main-page-header-disabled vector-feature-sticky-header-disabled vector-feature-page-tools-pinned-disabled vector-feature-toc-pinned-clientpref-1 vector-feature-main-menu-pinned-disabled vector-feature-limited-width-clientpref-1 vector-feature-limited-width-content-enabled vector-feature-custom-font-size-clientpref-1 vector-feature-appearance-pinned-clientpref-1 vector-feature-night-mode-enabled skin-theme-clientpref-day vector-toc-available";var cookie=document.cookie.match(/(?:^|; )enwikimwclientpreferences=([^;]+)/);if(cookie){cookie[1].split('%2C').forEach(function(pref){className=className.replace(new RegExp('(^| )'+pref.replace(/-clientpref-\w+$|[^\w-]+/g,'')+'-clientpref-\\w+( |$)'),'$1'+pref+'$2');});}document.documentElement.className=className;}());RLCONF={"wgBreakFrames":false,"wgSeparatorTransformTable":["",""],"wgDigitTransformTable":["",""],"wgDefaultDateFormat":"dmy", "wgMonthNames":["","January","February","March","April","May","June","July","August","September","October","November","December"],"wgRequestId":"808156c8-4910-93ff-8261-13311a35e41f","wgCanonicalNamespace":"","wgCanonicalSpecialPageName":false,"wgNamespaceNumber":0,"wgPageName":"Rebreather_diving","wgTitle":"Rebreather diving","wgCurRevisionId":1255436050,"wgRevisionId":1255436050,"wgArticleId":39194607,"wgIsArticle":true,"wgIsRedirect":false,"wgAction":"view","wgUserName":null,"wgUserGroups":["*"],"wgCategories":["CS1: long volume value","All articles with dead external links","Articles with dead external links from June 2024","Articles with short description","Short description matches Wikidata","Use dmy dates from May 2022","All articles with unsourced statements","Articles with unsourced statements from April 2013","Articles with unsourced statements from May 2021","Articles to be expanded from May 2021","All articles to be expanded", "Articles with unsourced statements from June 2024","Articles to be expanded from September 2024","Articles to be expanded from February 2024","Articles to be expanded from May 2024","Wikipedia articles needing clarification from October 2021","Underwater diving modes"],"wgPageViewLanguage":"en","wgPageContentLanguage":"en","wgPageContentModel":"wikitext","wgRelevantPageName":"Rebreather_diving","wgRelevantArticleId":39194607,"wgIsProbablyEditable":true,"wgRelevantPageIsProbablyEditable":true,"wgRestrictionEdit":[],"wgRestrictionMove":[],"wgRedirectedFrom":"Venting_the_rebreather_loop","wgNoticeProject":"wikipedia","wgCiteReferencePreviewsActive":false,"wgFlaggedRevsParams":{"tags":{"status":{"levels":1}}},"wgMediaViewerOnClick":true,"wgMediaViewerEnabledByDefault":true,"wgPopupsFlags":0,"wgVisualEditor":{"pageLanguageCode":"en","pageLanguageDir":"ltr","pageVariantFallbacks":"en"},"wgMFDisplayWikibaseDescriptions":{"search":true,"watchlist":true,"tagline":false,"nearby":true}, "wgWMESchemaEditAttemptStepOversample":false,"wgWMEPageLength":200000,"wgInternalRedirectTargetUrl":"/wiki/Rebreather_diving#Venting_the_loop","wgRelatedArticlesCompat":[],"wgCentralAuthMobileDomain":false,"wgEditSubmitButtonLabelPublish":true,"wgULSPosition":"interlanguage","wgULSisCompactLinksEnabled":false,"wgVector2022LanguageInHeader":true,"wgULSisLanguageSelectorEmpty":false,"wgWikibaseItemId":"Q12066983","wgCheckUserClientHintsHeadersJsApi":["brands","architecture","bitness","fullVersionList","mobile","model","platform","platformVersion"],"GEHomepageSuggestedEditsEnableTopics":true,"wgGETopicsMatchModeEnabled":false,"wgGEStructuredTaskRejectionReasonTextInputEnabled":false,"wgGELevelingUpEnabledForUser":false};RLSTATE={"ext.globalCssJs.user.styles":"ready","site.styles":"ready","user.styles":"ready","ext.globalCssJs.user":"ready","user":"ready","user.options":"loading","ext.cite.styles":"ready","ext.math.styles":"ready","mediawiki.page.gallery.styles":"ready", "skins.vector.search.codex.styles":"ready","skins.vector.styles":"ready","skins.vector.icons":"ready","jquery.makeCollapsible.styles":"ready","ext.wikimediamessages.styles":"ready","ext.visualEditor.desktopArticleTarget.noscript":"ready","ext.uls.interlanguage":"ready","wikibase.client.init":"ready","ext.wikimediaBadges":"ready"};RLPAGEMODULES=["mediawiki.action.view.redirect","ext.cite.ux-enhancements","mediawiki.page.gallery","mediawiki.page.media","site","mediawiki.page.ready","jquery.makeCollapsible","mediawiki.toc","skins.vector.js","ext.centralNotice.geoIP","ext.centralNotice.startUp","ext.gadget.ReferenceTooltips","ext.gadget.switcher","ext.urlShortener.toolbar","ext.centralauth.centralautologin","mmv.bootstrap","ext.popups","ext.visualEditor.desktopArticleTarget.init","ext.visualEditor.targetLoader","ext.echo.centralauth","ext.eventLogging","ext.wikimediaEvents","ext.navigationTiming","ext.uls.interface","ext.cx.eventlogging.campaigns","ext.cx.uls.quick.actions", "wikibase.client.vector-2022","ext.checkUser.clientHints","ext.growthExperiments.SuggestedEditSession","wikibase.sidebar.tracking"];</script> <script>(RLQ=window.RLQ||[]).push(function(){mw.loader.impl(function(){return["user.options@12s5i",function($,jQuery,require,module){mw.user.tokens.set({"patrolToken":"+\\","watchToken":"+\\","csrfToken":"+\\"}); }];});});</script> <link rel="stylesheet" href="/w/load.php?lang=en&modules=ext.cite.styles%7Cext.math.styles%7Cext.uls.interlanguage%7Cext.visualEditor.desktopArticleTarget.noscript%7Cext.wikimediaBadges%7Cext.wikimediamessages.styles%7Cjquery.makeCollapsible.styles%7Cmediawiki.page.gallery.styles%7Cskins.vector.icons%2Cstyles%7Cskins.vector.search.codex.styles%7Cwikibase.client.init&only=styles&skin=vector-2022"> <script async="" src="/w/load.php?lang=en&modules=startup&only=scripts&raw=1&skin=vector-2022"></script> <meta name="ResourceLoaderDynamicStyles" content=""> <link rel="stylesheet" href="/w/load.php?lang=en&modules=site.styles&only=styles&skin=vector-2022"> <meta name="generator" content="MediaWiki 1.44.0-wmf.4"> <meta name="referrer" content="origin"> <meta name="referrer" content="origin-when-cross-origin"> <meta name="robots" content="max-image-preview:standard"> <meta name="format-detection" content="telephone=no"> <meta property="og:image" content="https://upload.wikimedia.org/wikipedia/commons/5/5d/USMC_combatant_diving_%282nd_Recon_Bn%29.jpg"> <meta property="og:image:width" content="1200"> <meta property="og:image:height" content="842"> <meta property="og:image" content="https://upload.wikimedia.org/wikipedia/commons/5/5d/USMC_combatant_diving_%282nd_Recon_Bn%29.jpg"> <meta property="og:image:width" content="800"> <meta property="og:image:height" content="561"> <meta property="og:image" content="https://upload.wikimedia.org/wikipedia/commons/thumb/5/5d/USMC_combatant_diving_%282nd_Recon_Bn%29.jpg/640px-USMC_combatant_diving_%282nd_Recon_Bn%29.jpg"> <meta property="og:image:width" content="640"> <meta property="og:image:height" content="449"> <meta name="viewport" content="width=1120"> <meta property="og:title" content="Rebreather diving - Wikipedia"> <meta property="og:type" content="website"> <link rel="preconnect" href="//upload.wikimedia.org"> <link rel="alternate" media="only screen and (max-width: 640px)" href="//en.m.wikipedia.org/wiki/Rebreather_diving#Venting_the_loop"> <link rel="alternate" type="application/x-wiki" title="Edit this page" href="/w/index.php?title=Rebreather_diving&action=edit"> <link rel="apple-touch-icon" href="/static/apple-touch/wikipedia.png"> <link rel="icon" href="/static/favicon/wikipedia.ico"> <link rel="search" type="application/opensearchdescription+xml" href="/w/rest.php/v1/search" title="Wikipedia (en)"> <link rel="EditURI" type="application/rsd+xml" href="//en.wikipedia.org/w/api.php?action=rsd"> <link rel="canonical" href="https://en.wikipedia.org/wiki/Rebreather_diving#Venting_the_loop"> <link rel="license" href="https://creativecommons.org/licenses/by-sa/4.0/deed.en"> <link rel="alternate" type="application/atom+xml" title="Wikipedia Atom feed" href="/w/index.php?title=Special:RecentChanges&feed=atom"> <link rel="dns-prefetch" href="//meta.wikimedia.org" /> <link rel="dns-prefetch" href="//login.wikimedia.org"> </head> <body class="skin--responsive skin-vector skin-vector-search-vue mediawiki ltr sitedir-ltr mw-hide-empty-elt ns-0 ns-subject mw-editable page-Rebreather_diving rootpage-Rebreather_diving skin-vector-2022 action-view"><a class="mw-jump-link" href="#bodyContent">Jump to content</a> <div class="vector-header-container"> <header class="vector-header mw-header"> <div class="vector-header-start"> <nav class="vector-main-menu-landmark" aria-label="Site"> <div id="vector-main-menu-dropdown" class="vector-dropdown vector-main-menu-dropdown vector-button-flush-left vector-button-flush-right" > <input type="checkbox" id="vector-main-menu-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-main-menu-dropdown" class="vector-dropdown-checkbox " aria-label="Main menu" > <label id="vector-main-menu-dropdown-label" for="vector-main-menu-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-menu mw-ui-icon-wikimedia-menu"></span> <span class="vector-dropdown-label-text">Main menu</span> </label> <div class="vector-dropdown-content"> <div id="vector-main-menu-unpinned-container" class="vector-unpinned-container"> <div id="vector-main-menu" class="vector-main-menu vector-pinnable-element"> <div class="vector-pinnable-header vector-main-menu-pinnable-header vector-pinnable-header-unpinned" data-feature-name="main-menu-pinned" data-pinnable-element-id="vector-main-menu" data-pinned-container-id="vector-main-menu-pinned-container" data-unpinned-container-id="vector-main-menu-unpinned-container" > <div class="vector-pinnable-header-label">Main menu</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-main-menu.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-main-menu.unpin">hide</button> </div> <div id="p-navigation" class="vector-menu mw-portlet mw-portlet-navigation" > <div class="vector-menu-heading"> Navigation </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="n-mainpage-description" class="mw-list-item"><a href="/wiki/Main_Page" title="Visit the main page [z]" accesskey="z"><span>Main page</span></a></li><li id="n-contents" class="mw-list-item"><a href="/wiki/Wikipedia:Contents" title="Guides to browsing Wikipedia"><span>Contents</span></a></li><li id="n-currentevents" class="mw-list-item"><a href="/wiki/Portal:Current_events" title="Articles related to current events"><span>Current events</span></a></li><li id="n-randompage" class="mw-list-item"><a href="/wiki/Special:Random" title="Visit a randomly selected article [x]" accesskey="x"><span>Random article</span></a></li><li id="n-aboutsite" class="mw-list-item"><a href="/wiki/Wikipedia:About" title="Learn about Wikipedia and how it works"><span>About Wikipedia</span></a></li><li id="n-contactpage" class="mw-list-item"><a href="//en.wikipedia.org/wiki/Wikipedia:Contact_us" title="How to contact Wikipedia"><span>Contact us</span></a></li> </ul> </div> </div> <div id="p-interaction" class="vector-menu mw-portlet mw-portlet-interaction" > <div class="vector-menu-heading"> Contribute </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="n-help" class="mw-list-item"><a href="/wiki/Help:Contents" title="Guidance on how to use and edit Wikipedia"><span>Help</span></a></li><li id="n-introduction" class="mw-list-item"><a href="/wiki/Help:Introduction" title="Learn how to edit Wikipedia"><span>Learn to edit</span></a></li><li id="n-portal" class="mw-list-item"><a href="/wiki/Wikipedia:Community_portal" title="The hub for editors"><span>Community portal</span></a></li><li id="n-recentchanges" class="mw-list-item"><a href="/wiki/Special:RecentChanges" title="A list of recent changes to Wikipedia [r]" accesskey="r"><span>Recent changes</span></a></li><li id="n-upload" class="mw-list-item"><a href="/wiki/Wikipedia:File_upload_wizard" title="Add images or other media for use on Wikipedia"><span>Upload file</span></a></li> </ul> </div> </div> </div> </div> </div> </div> </nav> <a href="/wiki/Main_Page" class="mw-logo"> <img class="mw-logo-icon" src="/static/images/icons/wikipedia.png" alt="" aria-hidden="true" height="50" width="50"> <span class="mw-logo-container skin-invert"> <img class="mw-logo-wordmark" alt="Wikipedia" src="/static/images/mobile/copyright/wikipedia-wordmark-en.svg" style="width: 7.5em; height: 1.125em;"> <img class="mw-logo-tagline" alt="The Free Encyclopedia" src="/static/images/mobile/copyright/wikipedia-tagline-en.svg" width="117" height="13" style="width: 7.3125em; height: 0.8125em;"> </span> </a> </div> <div class="vector-header-end"> <div id="p-search" role="search" class="vector-search-box-vue vector-search-box-collapses vector-search-box-show-thumbnail vector-search-box-auto-expand-width vector-search-box"> <a href="/wiki/Special:Search" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only search-toggle" title="Search Wikipedia [f]" accesskey="f"><span class="vector-icon mw-ui-icon-search mw-ui-icon-wikimedia-search"></span> <span>Search</span> </a> <div class="vector-typeahead-search-container"> <div class="cdx-typeahead-search cdx-typeahead-search--show-thumbnail cdx-typeahead-search--auto-expand-width"> <form action="/w/index.php" id="searchform" class="cdx-search-input cdx-search-input--has-end-button"> <div id="simpleSearch" class="cdx-search-input__input-wrapper" data-search-loc="header-moved"> <div class="cdx-text-input cdx-text-input--has-start-icon"> <input class="cdx-text-input__input" type="search" name="search" placeholder="Search Wikipedia" aria-label="Search Wikipedia" autocapitalize="sentences" title="Search Wikipedia [f]" accesskey="f" id="searchInput" > <span class="cdx-text-input__icon cdx-text-input__start-icon"></span> </div> <input type="hidden" name="title" value="Special:Search"> </div> <button class="cdx-button cdx-search-input__end-button">Search</button> </form> </div> </div> </div> <nav class="vector-user-links vector-user-links-wide" aria-label="Personal tools"> <div class="vector-user-links-main"> <div id="p-vector-user-menu-preferences" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <div id="p-vector-user-menu-userpage" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <nav class="vector-appearance-landmark" aria-label="Appearance"> <div id="vector-appearance-dropdown" class="vector-dropdown " title="Change the appearance of the page's font size, width, and color" > <input type="checkbox" id="vector-appearance-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-appearance-dropdown" class="vector-dropdown-checkbox " aria-label="Appearance" > <label id="vector-appearance-dropdown-label" for="vector-appearance-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-appearance mw-ui-icon-wikimedia-appearance"></span> <span class="vector-dropdown-label-text">Appearance</span> </label> <div class="vector-dropdown-content"> <div id="vector-appearance-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <div id="p-vector-user-menu-notifications" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <div id="p-vector-user-menu-overflow" class="vector-menu mw-portlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-sitesupport-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="https://donate.wikimedia.org/wiki/Special:FundraiserRedirector?utm_source=donate&utm_medium=sidebar&utm_campaign=C13_en.wikipedia.org&uselang=en" class=""><span>Donate</span></a> </li> <li id="pt-createaccount-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="/w/index.php?title=Special:CreateAccount&returnto=Rebreather+diving" title="You are encouraged to create an account and log in; however, it is not mandatory" class=""><span>Create account</span></a> </li> <li id="pt-login-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="/w/index.php?title=Special:UserLogin&returnto=Rebreather+diving" title="You're encouraged to log in; however, it's not mandatory. [o]" accesskey="o" class=""><span>Log in</span></a> </li> </ul> </div> </div> </div> <div id="vector-user-links-dropdown" class="vector-dropdown vector-user-menu vector-button-flush-right vector-user-menu-logged-out" title="Log in and more options" > <input type="checkbox" id="vector-user-links-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-user-links-dropdown" class="vector-dropdown-checkbox " aria-label="Personal tools" > <label id="vector-user-links-dropdown-label" for="vector-user-links-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-ellipsis mw-ui-icon-wikimedia-ellipsis"></span> <span class="vector-dropdown-label-text">Personal tools</span> </label> <div class="vector-dropdown-content"> <div id="p-personal" class="vector-menu mw-portlet mw-portlet-personal user-links-collapsible-item" title="User menu" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-sitesupport" class="user-links-collapsible-item mw-list-item"><a href="https://donate.wikimedia.org/wiki/Special:FundraiserRedirector?utm_source=donate&utm_medium=sidebar&utm_campaign=C13_en.wikipedia.org&uselang=en"><span>Donate</span></a></li><li id="pt-createaccount" class="user-links-collapsible-item mw-list-item"><a href="/w/index.php?title=Special:CreateAccount&returnto=Rebreather+diving" title="You are encouraged to create an account and log in; however, it is not mandatory"><span class="vector-icon mw-ui-icon-userAdd mw-ui-icon-wikimedia-userAdd"></span> <span>Create account</span></a></li><li id="pt-login" class="user-links-collapsible-item mw-list-item"><a href="/w/index.php?title=Special:UserLogin&returnto=Rebreather+diving" title="You're encouraged to log in; however, it's not mandatory. [o]" accesskey="o"><span class="vector-icon mw-ui-icon-logIn mw-ui-icon-wikimedia-logIn"></span> <span>Log in</span></a></li> </ul> </div> </div> <div id="p-user-menu-anon-editor" class="vector-menu mw-portlet mw-portlet-user-menu-anon-editor" > <div class="vector-menu-heading"> Pages for logged out editors <a href="/wiki/Help:Introduction" aria-label="Learn more about editing"><span>learn more</span></a> </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-anoncontribs" class="mw-list-item"><a href="/wiki/Special:MyContributions" title="A list of edits made from this IP address [y]" accesskey="y"><span>Contributions</span></a></li><li id="pt-anontalk" class="mw-list-item"><a href="/wiki/Special:MyTalk" title="Discussion about edits from this IP address [n]" accesskey="n"><span>Talk</span></a></li> </ul> </div> </div> </div> </div> </nav> </div> </header> </div> <div class="mw-page-container"> <div class="mw-page-container-inner"> <div class="vector-sitenotice-container"> <div id="siteNotice"></div> </div> <div class="vector-column-start"> <div class="vector-main-menu-container"> <div id="mw-navigation"> <nav id="mw-panel" class="vector-main-menu-landmark" aria-label="Site"> <div id="vector-main-menu-pinned-container" class="vector-pinned-container"> </div> </nav> </div> </div> <div class="vector-sticky-pinned-container"> <nav id="mw-panel-toc" aria-label="Contents" data-event-name="ui.sidebar-toc" class="mw-table-of-contents-container vector-toc-landmark"> <div id="vector-toc-pinned-container" class="vector-pinned-container"> <div id="vector-toc" class="vector-toc vector-pinnable-element"> <div class="vector-pinnable-header vector-toc-pinnable-header vector-pinnable-header-pinned" data-feature-name="toc-pinned" data-pinnable-element-id="vector-toc" > <h2 class="vector-pinnable-header-label">Contents</h2> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-toc.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-toc.unpin">hide</button> </div> <ul class="vector-toc-contents" id="mw-panel-toc-list"> <li id="toc-mw-content-text" class="vector-toc-list-item vector-toc-level-1"> <a href="#" class="vector-toc-link"> <div class="vector-toc-text">(Top)</div> </a> </li> <li id="toc-Comparison_with_open_circuit" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Comparison_with_open_circuit"> <div class="vector-toc-text"> <span class="vector-toc-numb">1</span> <span>Comparison with open circuit</span> </div> </a> <button aria-controls="toc-Comparison_with_open_circuit-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Comparison with open circuit subsection</span> </button> <ul id="toc-Comparison_with_open_circuit-sublist" class="vector-toc-list"> <li id="toc-Basic_principle" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Basic_principle"> <div class="vector-toc-text"> <span class="vector-toc-numb">1.1</span> <span>Basic principle</span> </div> </a> <ul id="toc-Basic_principle-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Advantages" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Advantages"> <div class="vector-toc-text"> <span class="vector-toc-numb">1.2</span> <span>Advantages</span> </div> </a> <ul id="toc-Advantages-sublist" class="vector-toc-list"> <li id="toc-Efficiency_advantages" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Efficiency_advantages"> <div class="vector-toc-text"> <span class="vector-toc-numb">1.2.1</span> <span>Efficiency advantages</span> </div> </a> <ul id="toc-Efficiency_advantages-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Feasibility_advantages" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Feasibility_advantages"> <div class="vector-toc-text"> <span class="vector-toc-numb">1.2.2</span> <span>Feasibility advantages</span> </div> </a> <ul id="toc-Feasibility_advantages-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Other_advantages" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Other_advantages"> <div class="vector-toc-text"> <span class="vector-toc-numb">1.2.3</span> <span>Other advantages</span> </div> </a> <ul id="toc-Other_advantages-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Disadvantages" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Disadvantages"> <div class="vector-toc-text"> <span class="vector-toc-numb">1.3</span> <span>Disadvantages</span> </div> </a> <ul id="toc-Disadvantages-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Other_differences" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Other_differences"> <div class="vector-toc-text"> <span class="vector-toc-numb">1.4</span> <span>Other differences</span> </div> </a> <ul id="toc-Other_differences-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Function" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Function"> <div class="vector-toc-text"> <span class="vector-toc-numb">2</span> <span>Function</span> </div> </a> <button aria-controls="toc-Function-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Function subsection</span> </button> <ul id="toc-Function-sublist" class="vector-toc-list"> <li id="toc-Scrubber_endurance" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Scrubber_endurance"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.1</span> <span>Scrubber endurance</span> </div> </a> <ul id="toc-Scrubber_endurance-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Controlling_the_mix" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Controlling_the_mix"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.2</span> <span>Controlling the mix</span> </div> </a> <ul id="toc-Controlling_the_mix-sublist" class="vector-toc-list"> <li id="toc-Set-points" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Set-points"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.2.1</span> <span>Set-points</span> </div> </a> <ul id="toc-Set-points-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Gas_endurance" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Gas_endurance"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.3</span> <span>Gas endurance</span> </div> </a> <ul id="toc-Gas_endurance-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Calculating_the_loop_mix" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Calculating_the_loop_mix"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>Calculating the loop mix</span> </div> </a> <button aria-controls="toc-Calculating_the_loop_mix-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Calculating the loop mix subsection</span> </button> <ul id="toc-Calculating_the_loop_mix-sublist" class="vector-toc-list"> <li id="toc-Oxygen_partial_pressure_in_a_semi-closed_rebreather" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Oxygen_partial_pressure_in_a_semi-closed_rebreather"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.1</span> <span>Oxygen partial pressure in a semi-closed rebreather</span> </div> </a> <ul id="toc-Oxygen_partial_pressure_in_a_semi-closed_rebreather-sublist" class="vector-toc-list"> <li id="toc-Constant_mass_flow" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Constant_mass_flow"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.1.1</span> <span>Constant mass flow</span> </div> </a> <ul id="toc-Constant_mass_flow-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Passive_addition" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Passive_addition"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.1.2</span> <span>Passive addition</span> </div> </a> <ul id="toc-Passive_addition-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Maximum_operating_depth" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Maximum_operating_depth"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.2</span> <span>Maximum operating depth</span> </div> </a> <ul id="toc-Maximum_operating_depth-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Safety" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Safety"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>Safety</span> </div> </a> <button aria-controls="toc-Safety-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Safety subsection</span> </button> <ul id="toc-Safety-sublist" class="vector-toc-list"> <li id="toc-Hazards" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Hazards"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.1</span> <span>Hazards</span> </div> </a> <ul id="toc-Hazards-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Inherent_limitations_of_the_types_of_rebreather" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Inherent_limitations_of_the_types_of_rebreather"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.2</span> <span>Inherent limitations of the types of rebreather</span> </div> </a> <ul id="toc-Inherent_limitations_of_the_types_of_rebreather-sublist" class="vector-toc-list"> <li id="toc-Oxygen_rebreather" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Oxygen_rebreather"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.2.1</span> <span>Oxygen rebreather</span> </div> </a> <ul id="toc-Oxygen_rebreather-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Active_addition_SCR" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Active_addition_SCR"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.2.2</span> <span>Active addition SCR</span> </div> </a> <ul id="toc-Active_addition_SCR-sublist" class="vector-toc-list"> <li id="toc-Constant_mass_flow_SCR" class="vector-toc-list-item vector-toc-level-4"> <a class="vector-toc-link" href="#Constant_mass_flow_SCR"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.2.2.1</span> <span>Constant mass flow SCR</span> </div> </a> <ul id="toc-Constant_mass_flow_SCR-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Demand_controlled_SCR" class="vector-toc-list-item vector-toc-level-4"> <a class="vector-toc-link" href="#Demand_controlled_SCR"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.2.2.2</span> <span>Demand controlled SCR</span> </div> </a> <ul id="toc-Demand_controlled_SCR-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Passive_addition_SCR" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Passive_addition_SCR"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.2.3</span> <span>Passive addition SCR</span> </div> </a> <ul id="toc-Passive_addition_SCR-sublist" class="vector-toc-list"> <li id="toc-Non-depth_compensated_PASCR" class="vector-toc-list-item vector-toc-level-4"> <a class="vector-toc-link" href="#Non-depth_compensated_PASCR"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.2.3.1</span> <span>Non-depth compensated PASCR</span> </div> </a> <ul id="toc-Non-depth_compensated_PASCR-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Depth_compensated_PASCR" class="vector-toc-list-item vector-toc-level-4"> <a class="vector-toc-link" href="#Depth_compensated_PASCR"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.2.3.2</span> <span>Depth compensated PASCR</span> </div> </a> <ul id="toc-Depth_compensated_PASCR-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Mixed_gas_CCR" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Mixed_gas_CCR"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.2.4</span> <span>Mixed gas CCR</span> </div> </a> <ul id="toc-Mixed_gas_CCR-sublist" class="vector-toc-list"> <li id="toc-Manually_controlled_CCR" class="vector-toc-list-item vector-toc-level-4"> <a class="vector-toc-link" href="#Manually_controlled_CCR"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.2.4.1</span> <span>Manually controlled CCR</span> </div> </a> <ul id="toc-Manually_controlled_CCR-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Electronically_controlled_CCR" class="vector-toc-list-item vector-toc-level-4"> <a class="vector-toc-link" href="#Electronically_controlled_CCR"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.2.4.2</span> <span>Electronically controlled CCR</span> </div> </a> <ul id="toc-Electronically_controlled_CCR-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> </ul> </li> <li id="toc-Failure_modes" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Failure_modes"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.3</span> <span>Failure modes</span> </div> </a> <ul id="toc-Failure_modes-sublist" class="vector-toc-list"> <li id="toc-Scrubber_failure" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Scrubber_failure"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.3.1</span> <span>Scrubber failure</span> </div> </a> <ul id="toc-Scrubber_failure-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Oxygen_monitoring_failure" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Oxygen_monitoring_failure"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.3.2</span> <span>Oxygen monitoring failure</span> </div> </a> <ul id="toc-Oxygen_monitoring_failure-sublist" class="vector-toc-list"> <li id="toc-Managing_cell_failure_in_an_electronic_rebreather_control_system" class="vector-toc-list-item vector-toc-level-4"> <a class="vector-toc-link" href="#Managing_cell_failure_in_an_electronic_rebreather_control_system"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.3.2.1</span> <span>Managing cell failure in an electronic rebreather control system</span> </div> </a> <ul id="toc-Managing_cell_failure_in_an_electronic_rebreather_control_system-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Gas_injection_control_circuit_failure" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Gas_injection_control_circuit_failure"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.3.3</span> <span>Gas injection control circuit failure</span> </div> </a> <ul id="toc-Gas_injection_control_circuit_failure-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Loop_flood" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Loop_flood"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.3.4</span> <span>Loop flood</span> </div> </a> <ul id="toc-Loop_flood-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Gas_leakage" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Gas_leakage"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.3.5</span> <span>Gas leakage</span> </div> </a> <ul id="toc-Gas_leakage-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-CMF_Orifice_blockage" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#CMF_Orifice_blockage"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.3.6</span> <span>CMF Orifice blockage</span> </div> </a> <ul id="toc-CMF_Orifice_blockage-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Risk" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Risk"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.4</span> <span>Risk</span> </div> </a> <ul id="toc-Risk-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Mitigation" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Mitigation"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.5</span> <span>Mitigation</span> </div> </a> <ul id="toc-Mitigation-sublist" class="vector-toc-list"> <li id="toc-Equipment_options" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Equipment_options"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.5.1</span> <span>Equipment options</span> </div> </a> <ul id="toc-Equipment_options-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Procedural_options" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Procedural_options"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.5.2</span> <span>Procedural options</span> </div> </a> <ul id="toc-Procedural_options-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Statistics" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Statistics"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.6</span> <span>Statistics</span> </div> </a> <ul id="toc-Statistics-sublist" class="vector-toc-list"> <li id="toc-Demographics" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Demographics"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.6.1</span> <span>Demographics</span> </div> </a> <ul id="toc-Demographics-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> </ul> </li> <li id="toc-Standard_operating_procedures" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Standard_operating_procedures"> <div class="vector-toc-text"> <span class="vector-toc-numb">5</span> <span>Standard operating procedures</span> </div> </a> <button aria-controls="toc-Standard_operating_procedures-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Standard operating procedures subsection</span> </button> <ul id="toc-Standard_operating_procedures-sublist" class="vector-toc-list"> <li id="toc-Assembly_and_predive_function_tests" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Assembly_and_predive_function_tests"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.1</span> <span>Assembly and predive function tests</span> </div> </a> <ul id="toc-Assembly_and_predive_function_tests-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Preventing_flooding_of_the_loop" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Preventing_flooding_of_the_loop"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.2</span> <span>Preventing flooding of the loop</span> </div> </a> <ul id="toc-Preventing_flooding_of_the_loop-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Oxygen_monitoring" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Oxygen_monitoring"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.3</span> <span>Oxygen monitoring</span> </div> </a> <ul id="toc-Oxygen_monitoring-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Monitoring_carbon_dioxide" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Monitoring_carbon_dioxide"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.4</span> <span>Monitoring carbon dioxide</span> </div> </a> <ul id="toc-Monitoring_carbon_dioxide-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Diluent_flush" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Diluent_flush"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.5</span> <span>Diluent flush</span> </div> </a> <ul id="toc-Diluent_flush-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Venting_the_loop" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Venting_the_loop"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.6</span> <span>Venting the loop</span> </div> </a> <ul id="toc-Venting_the_loop-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Draining_the_loop" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Draining_the_loop"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.7</span> <span>Draining the loop</span> </div> </a> <ul id="toc-Draining_the_loop-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Ascents_and_descents" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Ascents_and_descents"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.8</span> <span>Ascents and descents</span> </div> </a> <ul id="toc-Ascents_and_descents-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Buoyancy_control" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Buoyancy_control"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.9</span> <span>Buoyancy control</span> </div> </a> <ul id="toc-Buoyancy_control-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Trim" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Trim"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.10</span> <span>Trim</span> </div> </a> <ul id="toc-Trim-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Post_dive_checks,_cleaning_and_maintenance" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Post_dive_checks,_cleaning_and_maintenance"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.11</span> <span>Post dive checks, cleaning and maintenance</span> </div> </a> <ul id="toc-Post_dive_checks,_cleaning_and_maintenance-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Emergency_procedures" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Emergency_procedures"> <div class="vector-toc-text"> <span class="vector-toc-numb">6</span> <span>Emergency procedures</span> </div> </a> <button aria-controls="toc-Emergency_procedures-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Emergency procedures subsection</span> </button> <ul id="toc-Emergency_procedures-sublist" class="vector-toc-list"> <li id="toc-Bailout" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Bailout"> <div class="vector-toc-text"> <span class="vector-toc-numb">6.1</span> <span>Bailout</span> </div> </a> <ul id="toc-Bailout-sublist" class="vector-toc-list"> <li id="toc-Bailout_valve" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Bailout_valve"> <div class="vector-toc-text"> <span class="vector-toc-numb">6.1.1</span> <span>Bailout valve</span> </div> </a> <ul id="toc-Bailout_valve-sublist" class="vector-toc-list"> <li id="toc-Open_circuit_bailout_valve" class="vector-toc-list-item vector-toc-level-4"> <a class="vector-toc-link" href="#Open_circuit_bailout_valve"> <div class="vector-toc-text"> <span class="vector-toc-numb">6.1.1.1</span> <span>Open circuit bailout valve</span> </div> </a> <ul id="toc-Open_circuit_bailout_valve-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Closed_circuit_bailout_valve" class="vector-toc-list-item vector-toc-level-4"> <a class="vector-toc-link" href="#Closed_circuit_bailout_valve"> <div class="vector-toc-text"> <span class="vector-toc-numb">6.1.1.2</span> <span>Closed circuit bailout valve</span> </div> </a> <ul id="toc-Closed_circuit_bailout_valve-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Bailout_to_open_circuit" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Bailout_to_open_circuit"> <div class="vector-toc-text"> <span class="vector-toc-numb">6.1.2</span> <span>Bailout to open circuit</span> </div> </a> <ul id="toc-Bailout_to_open_circuit-sublist" class="vector-toc-list"> <li id="toc-Team_bailout" class="vector-toc-list-item vector-toc-level-4"> <a class="vector-toc-link" href="#Team_bailout"> <div class="vector-toc-text"> <span class="vector-toc-numb">6.1.2.1</span> <span>Team bailout</span> </div> </a> <ul id="toc-Team_bailout-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Bailout_to_rebreather" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Bailout_to_rebreather"> <div class="vector-toc-text"> <span class="vector-toc-numb">6.1.3</span> <span>Bailout to rebreather</span> </div> </a> <ul id="toc-Bailout_to_rebreather-sublist" class="vector-toc-list"> <li id="toc-Bailout_software" class="vector-toc-list-item vector-toc-level-4"> <a class="vector-toc-link" href="#Bailout_software"> <div class="vector-toc-text"> <span class="vector-toc-numb">6.1.3.1</span> <span>Bailout software</span> </div> </a> <ul id="toc-Bailout_software-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Bailout_rebreather_configurations" class="vector-toc-list-item vector-toc-level-4"> <a class="vector-toc-link" href="#Bailout_rebreather_configurations"> <div class="vector-toc-text"> <span class="vector-toc-numb">6.1.3.2</span> <span>Bailout rebreather configurations</span> </div> </a> <ul id="toc-Bailout_rebreather_configurations-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> </ul> </li> </ul> </li> <li id="toc-Training" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Training"> <div class="vector-toc-text"> <span class="vector-toc-numb">7</span> <span>Training</span> </div> </a> <button aria-controls="toc-Training-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Training subsection</span> </button> <ul id="toc-Training-sublist" class="vector-toc-list"> <li id="toc-Scientific_diver_training" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Scientific_diver_training"> <div class="vector-toc-text"> <span class="vector-toc-numb">7.1</span> <span>Scientific diver training</span> </div> </a> <ul id="toc-Scientific_diver_training-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Rebreather_Training_Council" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Rebreather_Training_Council"> <div class="vector-toc-text"> <span class="vector-toc-numb">7.2</span> <span>Rebreather Training Council</span> </div> </a> <ul id="toc-Rebreather_Training_Council-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Rebreather_Education_and_Safety_Association" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Rebreather_Education_and_Safety_Association"> <div class="vector-toc-text"> <span class="vector-toc-numb">7.3</span> <span>Rebreather Education and Safety Association</span> </div> </a> <ul id="toc-Rebreather_Education_and_Safety_Association-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-ISO_training_standards" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#ISO_training_standards"> <div class="vector-toc-text"> <span class="vector-toc-numb">7.4</span> <span>ISO training standards</span> </div> </a> <ul id="toc-ISO_training_standards-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-History" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#History"> <div class="vector-toc-text"> <span class="vector-toc-numb">8</span> <span>History</span> </div> </a> <button aria-controls="toc-History-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle History subsection</span> </button> <ul id="toc-History-sublist" class="vector-toc-list"> <li id="toc-Early_developments" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Early_developments"> <div class="vector-toc-text"> <span class="vector-toc-numb">8.1</span> <span>Early developments</span> </div> </a> <ul id="toc-Early_developments-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-World_War_II_era" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#World_War_II_era"> <div class="vector-toc-text"> <span class="vector-toc-numb">8.2</span> <span>World War II era</span> </div> </a> <ul id="toc-World_War_II_era-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Technical_diving_era" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Technical_diving_era"> <div class="vector-toc-text"> <span class="vector-toc-numb">8.3</span> <span>Technical diving era</span> </div> </a> <ul id="toc-Technical_diving_era-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Applications" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Applications"> <div class="vector-toc-text"> <span class="vector-toc-numb">9</span> <span>Applications</span> </div> </a> <button aria-controls="toc-Applications-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Applications subsection</span> </button> <ul id="toc-Applications-sublist" class="vector-toc-list"> <li id="toc-Military_diving" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Military_diving"> <div class="vector-toc-text"> <span class="vector-toc-numb">9.1</span> <span>Military diving</span> </div> </a> <ul id="toc-Military_diving-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Technical_diving" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Technical_diving"> <div class="vector-toc-text"> <span class="vector-toc-numb">9.2</span> <span>Technical diving</span> </div> </a> <ul id="toc-Technical_diving-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Recreational_diving" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Recreational_diving"> <div class="vector-toc-text"> <span class="vector-toc-numb">9.3</span> <span>Recreational diving</span> </div> </a> <ul id="toc-Recreational_diving-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Scientific_and_archaeological_diving" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Scientific_and_archaeological_diving"> <div class="vector-toc-text"> <span class="vector-toc-numb">9.4</span> <span>Scientific and archaeological diving</span> </div> </a> <ul id="toc-Scientific_and_archaeological_diving-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Mixed_mode_and_mixed_platform_diving" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Mixed_mode_and_mixed_platform_diving"> <div class="vector-toc-text"> <span class="vector-toc-numb">9.5</span> <span>Mixed mode and mixed platform diving</span> </div> </a> <ul id="toc-Mixed_mode_and_mixed_platform_diving-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-See_also" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#See_also"> <div class="vector-toc-text"> <span class="vector-toc-numb">10</span> <span>See also</span> </div> </a> <ul id="toc-See_also-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-References" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#References"> <div class="vector-toc-text"> <span class="vector-toc-numb">11</span> <span>References</span> </div> </a> <button aria-controls="toc-References-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle References subsection</span> </button> <ul id="toc-References-sublist" class="vector-toc-list"> <li id="toc-Sources" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Sources"> <div class="vector-toc-text"> <span class="vector-toc-numb">11.1</span> <span>Sources</span> </div> </a> <ul id="toc-Sources-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-External_links" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#External_links"> <div class="vector-toc-text"> <span class="vector-toc-numb">12</span> <span>External links</span> </div> </a> <ul id="toc-External_links-sublist" class="vector-toc-list"> </ul> </li> </ul> </div> </div> </nav> </div> </div> <div class="mw-content-container"> <main id="content" class="mw-body"> <header class="mw-body-header vector-page-titlebar"> <nav aria-label="Contents" class="vector-toc-landmark"> <div id="vector-page-titlebar-toc" class="vector-dropdown vector-page-titlebar-toc vector-button-flush-left" > <input type="checkbox" id="vector-page-titlebar-toc-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-titlebar-toc" class="vector-dropdown-checkbox " aria-label="Toggle the table of contents" > <label id="vector-page-titlebar-toc-label" for="vector-page-titlebar-toc-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-listBullet mw-ui-icon-wikimedia-listBullet"></span> <span class="vector-dropdown-label-text">Toggle the table of contents</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-titlebar-toc-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <h1 id="firstHeading" class="firstHeading mw-first-heading"><span class="mw-page-title-main">Rebreather diving</span></h1> <div id="p-lang-btn" class="vector-dropdown mw-portlet mw-portlet-lang" > <input type="checkbox" id="p-lang-btn-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-p-lang-btn" class="vector-dropdown-checkbox mw-interlanguage-selector" aria-label="This article exist only in this language. Add the article for other languages" > <label id="p-lang-btn-label" for="p-lang-btn-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive mw-portlet-lang-heading-0" aria-hidden="true" ><span class="vector-icon mw-ui-icon-language-progressive mw-ui-icon-wikimedia-language-progressive"></span> <span class="vector-dropdown-label-text">Add languages</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> <div class="after-portlet after-portlet-lang"><span class="uls-after-portlet-link"></span><span class="wb-langlinks-add wb-langlinks-link"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q12066983#sitelinks-wikipedia" title="Add interlanguage links" class="wbc-editpage">Add links</a></span></div> </div> </div> </div> </header> <div class="vector-page-toolbar"> <div class="vector-page-toolbar-container"> <div id="left-navigation"> <nav aria-label="Namespaces"> <div id="p-associated-pages" class="vector-menu vector-menu-tabs mw-portlet mw-portlet-associated-pages" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-nstab-main" class="selected vector-tab-noicon mw-list-item"><a href="/wiki/Rebreather_diving" title="View the content page [c]" accesskey="c"><span>Article</span></a></li><li id="ca-talk" class="vector-tab-noicon mw-list-item"><a href="/wiki/Talk:Rebreather_diving" rel="discussion" title="Discuss improvements to the content page [t]" accesskey="t"><span>Talk</span></a></li> </ul> </div> </div> <div id="vector-variants-dropdown" class="vector-dropdown emptyPortlet" > <input type="checkbox" id="vector-variants-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-variants-dropdown" class="vector-dropdown-checkbox " aria-label="Change language variant" > <label id="vector-variants-dropdown-label" for="vector-variants-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet" aria-hidden="true" ><span class="vector-dropdown-label-text">English</span> </label> <div class="vector-dropdown-content"> <div id="p-variants" class="vector-menu mw-portlet mw-portlet-variants emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> </div> </div> </nav> </div> <div id="right-navigation" class="vector-collapsible"> <nav aria-label="Views"> <div id="p-views" class="vector-menu vector-menu-tabs mw-portlet mw-portlet-views" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-view" class="selected vector-tab-noicon mw-list-item"><a href="/wiki/Rebreather_diving"><span>Read</span></a></li><li id="ca-edit" class="vector-tab-noicon mw-list-item"><a href="/w/index.php?title=Rebreather_diving&action=edit" title="Edit this page [e]" accesskey="e"><span>Edit</span></a></li><li id="ca-history" class="vector-tab-noicon mw-list-item"><a href="/w/index.php?title=Rebreather_diving&action=history" title="Past revisions of this page [h]" accesskey="h"><span>View history</span></a></li> </ul> </div> </div> </nav> <nav class="vector-page-tools-landmark" aria-label="Page tools"> <div id="vector-page-tools-dropdown" class="vector-dropdown vector-page-tools-dropdown" > <input type="checkbox" id="vector-page-tools-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-tools-dropdown" class="vector-dropdown-checkbox " aria-label="Tools" > <label id="vector-page-tools-dropdown-label" for="vector-page-tools-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet" aria-hidden="true" ><span class="vector-dropdown-label-text">Tools</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-tools-unpinned-container" class="vector-unpinned-container"> <div id="vector-page-tools" class="vector-page-tools vector-pinnable-element"> <div class="vector-pinnable-header vector-page-tools-pinnable-header vector-pinnable-header-unpinned" data-feature-name="page-tools-pinned" data-pinnable-element-id="vector-page-tools" data-pinned-container-id="vector-page-tools-pinned-container" data-unpinned-container-id="vector-page-tools-unpinned-container" > <div class="vector-pinnable-header-label">Tools</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-page-tools.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-page-tools.unpin">hide</button> </div> <div id="p-cactions" class="vector-menu mw-portlet mw-portlet-cactions emptyPortlet vector-has-collapsible-items" title="More options" > <div class="vector-menu-heading"> Actions </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-more-view" class="selected vector-more-collapsible-item mw-list-item"><a href="/wiki/Rebreather_diving"><span>Read</span></a></li><li id="ca-more-edit" class="vector-more-collapsible-item mw-list-item"><a href="/w/index.php?title=Rebreather_diving&action=edit" title="Edit this page [e]" accesskey="e"><span>Edit</span></a></li><li id="ca-more-history" class="vector-more-collapsible-item mw-list-item"><a href="/w/index.php?title=Rebreather_diving&action=history"><span>View history</span></a></li> </ul> </div> </div> <div id="p-tb" class="vector-menu mw-portlet mw-portlet-tb" > <div class="vector-menu-heading"> General </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="t-whatlinkshere" class="mw-list-item"><a href="/wiki/Special:WhatLinksHere/Rebreather_diving" title="List of all English Wikipedia pages containing links to this page [j]" accesskey="j"><span>What links here</span></a></li><li id="t-recentchangeslinked" class="mw-list-item"><a href="/wiki/Special:RecentChangesLinked/Rebreather_diving" rel="nofollow" title="Recent changes in pages linked from this page [k]" accesskey="k"><span>Related changes</span></a></li><li id="t-upload" class="mw-list-item"><a href="/wiki/Wikipedia:File_Upload_Wizard" title="Upload files [u]" accesskey="u"><span>Upload file</span></a></li><li id="t-specialpages" class="mw-list-item"><a href="/wiki/Special:SpecialPages" title="A list of all special pages [q]" accesskey="q"><span>Special pages</span></a></li><li id="t-permalink" class="mw-list-item"><a href="/w/index.php?title=Rebreather_diving&oldid=1255436050" title="Permanent link to this revision of this page"><span>Permanent link</span></a></li><li id="t-info" class="mw-list-item"><a href="/w/index.php?title=Rebreather_diving&action=info" title="More information about this page"><span>Page information</span></a></li><li id="t-cite" class="mw-list-item"><a href="/w/index.php?title=Special:CiteThisPage&page=Rebreather_diving&id=1255436050&wpFormIdentifier=titleform" title="Information on how to cite this page"><span>Cite this page</span></a></li><li id="t-urlshortener" class="mw-list-item"><a href="/w/index.php?title=Special:UrlShortener&url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2FRebreather_diving%23Venting_the_loop"><span>Get shortened URL</span></a></li><li id="t-urlshortener-qrcode" class="mw-list-item"><a href="/w/index.php?title=Special:QrCode&url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2FRebreather_diving%23Venting_the_loop"><span>Download QR code</span></a></li> </ul> </div> </div> <div id="p-coll-print_export" class="vector-menu mw-portlet mw-portlet-coll-print_export" > <div class="vector-menu-heading"> Print/export </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="coll-download-as-rl" class="mw-list-item"><a href="/w/index.php?title=Special:DownloadAsPdf&page=Rebreather_diving&action=show-download-screen" title="Download this page as a PDF file"><span>Download as PDF</span></a></li><li id="t-print" class="mw-list-item"><a href="/w/index.php?title=Rebreather_diving&printable=yes" title="Printable version of this page [p]" accesskey="p"><span>Printable version</span></a></li> </ul> </div> </div> <div id="p-wikibase-otherprojects" class="vector-menu mw-portlet mw-portlet-wikibase-otherprojects" > <div class="vector-menu-heading"> In other projects </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="t-wikibase" class="wb-otherproject-link wb-otherproject-wikibase-dataitem mw-list-item"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q12066983" title="Structured data on this page hosted by Wikidata [g]" accesskey="g"><span>Wikidata item</span></a></li> </ul> </div> </div> </div> </div> </div> </div> </nav> </div> </div> </div> <div class="vector-column-end"> <div class="vector-sticky-pinned-container"> <nav class="vector-page-tools-landmark" aria-label="Page tools"> <div id="vector-page-tools-pinned-container" class="vector-pinned-container"> </div> </nav> <nav class="vector-appearance-landmark" aria-label="Appearance"> <div id="vector-appearance-pinned-container" class="vector-pinned-container"> <div id="vector-appearance" class="vector-appearance vector-pinnable-element"> <div class="vector-pinnable-header vector-appearance-pinnable-header vector-pinnable-header-pinned" data-feature-name="appearance-pinned" data-pinnable-element-id="vector-appearance" data-pinned-container-id="vector-appearance-pinned-container" data-unpinned-container-id="vector-appearance-unpinned-container" > <div class="vector-pinnable-header-label">Appearance</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-appearance.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-appearance.unpin">hide</button> </div> </div> </div> </nav> </div> </div> <div id="bodyContent" class="vector-body" aria-labelledby="firstHeading" data-mw-ve-target-container> <div class="vector-body-before-content"> <div class="mw-indicators"> </div> <div id="siteSub" class="noprint">From Wikipedia, the free encyclopedia</div> </div> <div id="contentSub"><div id="mw-content-subtitle"><span class="mw-redirectedfrom">(Redirected from <a href="/w/index.php?title=Venting_the_rebreather_loop&redirect=no" class="mw-redirect" title="Venting the rebreather loop">Venting the rebreather loop</a>)</span></div></div> <div id="mw-content-text" class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none"> Underwater diving using self contained breathing gas recycling apparatus </div> <style data-mw-deduplicate="TemplateStyles:r1236090951">.mw-parser-output .hatnote{font-style:italic}.mw-parser-output div.hatnote{padding-left:1.6em;margin-bottom:0.5em}.mw-parser-output .hatnote i{font-style:normal}.mw-parser-output .hatnote+link+.hatnote{margin-top:-0.5em}@media print{body.ns-0 .mw-parser-output .hatnote{display:none!important}}</style><div role="note" class="hatnote navigation-not-searchable">This article is about the activity and procedures. For the equipment, see <a href="/wiki/Diving_rebreather" title="Diving rebreather">Diving rebreather</a>.</div> <p class="mw-empty-elt"> </p> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:USMC_combatant_diving_(2nd_Recon_Bn).jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/5/5d/USMC_combatant_diving_%282nd_Recon_Bn%29.jpg/220px-USMC_combatant_diving_%282nd_Recon_Bn%29.jpg" decoding="async" width="220" height="154" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/5/5d/USMC_combatant_diving_%282nd_Recon_Bn%29.jpg/330px-USMC_combatant_diving_%282nd_Recon_Bn%29.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/5/5d/USMC_combatant_diving_%282nd_Recon_Bn%29.jpg/440px-USMC_combatant_diving_%282nd_Recon_Bn%29.jpg 2x" data-file-width="768" data-file-height="539" /></a><figcaption>2nd Reconnaissance Battalion combat diver training with the Dräger LAR V rebreather</figcaption></figure> <p><b>Rebreather diving</b> is <a href="/wiki/Underwater_diving" title="Underwater diving">underwater diving</a> using <a href="/wiki/Diving_rebreather" title="Diving rebreather">diving rebreathers</a>, a class of underwater breathing apparatus which recirculate the <a href="/wiki/Breathing_gas" title="Breathing gas">breathing gas</a> exhaled by the diver after replacing the <a href="/wiki/Oxygen" title="Oxygen">oxygen</a> used and removing the <a href="/wiki/Carbon_dioxide" title="Carbon dioxide">carbon dioxide</a> metabolic product. Rebreather diving is practiced by recreational, military and scientific divers in applications where it has advantages over open circuit <a href="/wiki/Scuba_set" title="Scuba set">scuba</a>, and surface supply of breathing gas is impracticable. The main advantages of rebreather diving are extended gas endurance, low noise levels, and lack of bubbles.<sup id="cite_ref-apdiving_1-0" class="reference"><a href="#cite_note-apdiving-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p><p>Rebreathers are generally used for <a href="/wiki/Scuba_diving" title="Scuba diving">scuba applications</a>, but are also occasionally used for <a href="/wiki/Bailout_(diving)" class="mw-redirect" title="Bailout (diving)">bailout</a> systems for <a href="/wiki/Surface-supplied_diving" title="Surface-supplied diving">surface-supplied diving</a>. <a href="/wiki/Gas_reclaim_system" class="mw-redirect" title="Gas reclaim system">Gas reclaim systems</a> used for deep heliox diving use similar technology to rebreathers, as do <a href="/wiki/Saturation_diving" title="Saturation diving">saturation diving</a> <a href="/wiki/Life-support_system" title="Life-support system">life-support systems</a>, but in these applications the gas recycling equipment is not carried by the diver. <a href="/wiki/Atmospheric_diving_suit" title="Atmospheric diving suit">Atmospheric diving suits</a> also carry rebreather technology to recycle breathing gas as part of the life-support system, but this article covers the procedures of ambient pressure diving using rebreathers carried by the diver. </p><p>Rebreathers are generally more complex to use than open circuit scuba, and have more potential <a href="/wiki/Point_of_failure" class="mw-redirect" title="Point of failure">points of failure</a>, so acceptably safe use requires a greater level of skill, attention and situational awareness, which is usually derived from understanding the systems, diligent maintenance and overlearning the practical skills of operation and <a href="/wiki/Fault_recovery" class="mw-redirect" title="Fault recovery">fault recovery</a>. Fault tolerant design can make a rebreather less likely to fail in a way that immediately endangers the user, and reduces the task loading on the diver which in turn may lower the risk of operator error. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Comparison_with_open_circuit">Comparison with open circuit</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=1" title="Edit section: Comparison with open circuit"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading3"><h3 id="Basic_principle">Basic principle</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=2" title="Edit section: Basic principle"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>At shallow depths, a diver using <a href="/wiki/Open-circuit_scuba" class="mw-redirect" title="Open-circuit scuba">open-circuit</a> breathing apparatus typically only uses about a quarter of the oxygen in the air that is breathed in, which is about 4 to 5% of the inspired volume. The remaining oxygen is exhaled along with <a href="/wiki/Nitrogen" title="Nitrogen">nitrogen</a> and carbon dioxide – about 95% of the volume. As the diver goes deeper, much the same mass of oxygen is used, which represents an increasingly smaller fraction of the inhaled gas. Since only a small part of the oxygen, and virtually none of the inert gas is consumed, every exhaled breath from an open-circuit scuba set represents at least 95% wasted potentially useful gas volume, which has to be replaced from the breathing gas supply.<sup id="cite_ref-Rhea_2021_2-0" class="reference"><a href="#cite_note-Rhea_2021-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-apdiving_1-1" class="reference"><a href="#cite_note-apdiving-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p><p>A rebreather retains most of the exhaled gas for re-use and does not discharge it immediately to the surroundings.<sup id="cite_ref-rebreather2.0_3-0" class="reference"><a href="#cite_note-rebreather2.0-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Goble_4-0" class="reference"><a href="#cite_note-Goble-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> The inert gas and unused oxygen is kept for reuse, and the rebreather adds gas to replace the oxygen that was consumed, and removes the carbon dioxide.<sup id="cite_ref-rebreather2.0_3-1" class="reference"><a href="#cite_note-rebreather2.0-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> Thus, the gas recirculated in the rebreather remains breathable and supports life and the diver needs only to carry a fraction of the gas that would be needed for an open-circuit system. The saving is proportional to the ambient pressure, so is greater for deeper dives, and is particularly significant when expensive mixtures containing helium are used as the inert gas diluent. The rebreather also adds gas to compensate for compression when dive depth increases, and vents gas to prevent overexpansion when depth decreases.<sup id="cite_ref-Rhea_2021_2-1" class="reference"><a href="#cite_note-Rhea_2021-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-ap_vision_5-0" class="reference"><a href="#cite_note-ap_vision-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-apdiving_1-2" class="reference"><a href="#cite_note-apdiving-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Advantages">Advantages</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=3" title="Edit section: Advantages"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Aa_US_Navy_explosive_ordnance_disposal_(EOD)_divers.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/9/9e/Aa_US_Navy_explosive_ordnance_disposal_%28EOD%29_divers.jpg/220px-Aa_US_Navy_explosive_ordnance_disposal_%28EOD%29_divers.jpg" decoding="async" width="220" height="287" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/9/9e/Aa_US_Navy_explosive_ordnance_disposal_%28EOD%29_divers.jpg/330px-Aa_US_Navy_explosive_ordnance_disposal_%28EOD%29_divers.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/9/9e/Aa_US_Navy_explosive_ordnance_disposal_%28EOD%29_divers.jpg/440px-Aa_US_Navy_explosive_ordnance_disposal_%28EOD%29_divers.jpg 2x" data-file-width="459" data-file-height="599" /></a><figcaption><a href="/wiki/US_Navy" class="mw-redirect" title="US Navy">US Navy</a> <a href="/wiki/Explosive_ordnance_disposal" class="mw-redirect" title="Explosive ordnance disposal">explosive ordnance disposal</a> (EOD) divers</figcaption></figure> <div class="mw-heading mw-heading4"><h4 id="Efficiency_advantages">Efficiency advantages</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=4" title="Edit section: Efficiency advantages"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The main advantage of the rebreather over open circuit breathing equipment is economical use of gas. With open circuit scuba, the entire breath is expelled into the surrounding water when the diver exhales. A breath inhaled from an open circuit scuba system with cylinders filled with compressed air is about 21%<sup id="cite_ref-popmech-dec06-58_6-0" class="reference"><a href="#cite_note-popmech-dec06-58-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> oxygen. When that breath is exhaled back into the surrounding environment, it has an oxygen level in the range of 15 to 16% when the diver is at atmospheric pressure.<sup id="cite_ref-popmech-dec06-58_6-1" class="reference"><a href="#cite_note-popmech-dec06-58-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> This leaves the available oxygen use at about 25%; the remaining 75% is lost. As the remaining 79% of the breathing gas (mostly <a href="/wiki/Nitrogen" title="Nitrogen">nitrogen</a>) is inert, the diver on open-circuit scuba only uses about 5% of the cylinders' contents.<sup id="cite_ref-apdiving_1-3" class="reference"><a href="#cite_note-apdiving-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p><p>At depth, this advantage of a rebreather is even more marked. The diver's metabolic rate is independent of ambient pressure (i.e. depth), so the oxygen consumption rate does not change with depth. The production of carbon dioxide does not change either since it also depends on the metabolic rate. This is a marked difference from open circuit where the amount of gas consumed increases as depth increases since the density of the inhaled gas increases with pressure, and the volume of a breath remains almost unchanged.<sup id="cite_ref-apdiving_1-4" class="reference"><a href="#cite_note-apdiving-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading4"><h4 id="Feasibility_advantages">Feasibility advantages</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=5" title="Edit section: Feasibility advantages"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Very long or deep dives using open circuit scuba equipment may not be feasible as there are limits to the number and weight of <a href="/wiki/Diving_cylinder" title="Diving cylinder">diving cylinders</a> the diver can carry. The economy of gas consumption of a rebreather is also useful when the gas mix being breathed contains expensive gases, such as <a href="/wiki/Helium" title="Helium">helium</a>. In normal use at constant depth, only oxygen is consumed: small volumes of inert gases are lost during any one dive, due mainly to venting of the gas as it expands on ascent. For example, a closed circuit rebreather diver theoretically need not use up any more diluent gas after reaching the full depth of the dive. On ascent, no diluent is added, but most of the gas in the loop is lost as it expands and is vented. A very small amount of <a href="/wiki/Trimix_(breathing_gas)" title="Trimix (breathing gas)">trimix</a> could therefore last for many dives. It is possible for a 3-litre (19 cubic foot <a href="/wiki/Diving_cylinder#Cylinder_capacity" title="Diving cylinder">nominal capacity</a>) diluent cylinder to last for eight 40 m (130 ft) dives.<sup id="cite_ref-apdiving_1-5" class="reference"><a href="#cite_note-apdiving-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading4"><h4 id="Other_advantages">Other advantages</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=6" title="Edit section: Other advantages"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li>Except on ascent, closed circuit rebreathers produce no bubbles during normal operation, and make no bubble noise and much less gas hissing, compared to <a href="/wiki/Open-circuit_scuba" class="mw-redirect" title="Open-circuit scuba">open-circuit scuba</a>;<sup id="cite_ref-popmech-dec06-58_6-2" class="reference"><a href="#cite_note-popmech-dec06-58-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> this can conceal <a href="/wiki/Military_diving" title="Military diving">military divers</a> and allow divers engaged in <a href="/wiki/Marine_biology" title="Marine biology">marine biology</a> and <a href="/wiki/Underwater_photography" title="Underwater photography">underwater photography</a> to avoid alarming marine animals and thereby get closer to them.<sup id="cite_ref-Lobel2005_7-0" class="reference"><a href="#cite_note-Lobel2005-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup></li> <li>This lack of bubbles allows wreck divers to enter enclosed areas on sunken ships without slowly filling them with air, which can accelerate rusting, and is also an advantage in cave diving if there is loose material on the ceiling which can be dislodged by bubbles, reducing visibility.</li> <li>The fully closed circuit rebreather can be used to optimise the proportion of inert gases in the breathing mix, and therefore minimise the <a href="/wiki/Decompression_stop" class="mw-redirect" title="Decompression stop">decompression</a> requirements of the diver, by maintaining a specific and nearly constant relatively high oxygen <a href="/wiki/Partial_pressure" title="Partial pressure">partial pressure</a> (<span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle P_{O_{2}}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>P</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle P_{O_{2}}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/a72ca8571542023f2367e1febc37581c12e0b1d8" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:3.81ex; height:2.843ex;" alt="{\displaystyle P_{O_{2}}}"></span>) at all depths.</li> <li>The breathing gas in a rebreather loop is warmer and more humid than the dry and cold gas from open circuit equipment, making it more comfortable to breathe on long dives and causing less dehydration and chilling of the diver.<sup id="cite_ref-Josan-Drinceanu_et_al_8-0" class="reference"><a href="#cite_note-Josan-Drinceanu_et_al-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup></li> <li>Many rebreathers have a system of oxygen sensors, which allow the diver or a control circuit to adjust the partial pressure of oxygen. This can offer a dramatic advantage at the end of deeper dives, where a diver can raise the partial pressure of oxygen during decompression, permitting shorter decompression times. Care must be taken that the partial pressure of oxygen is not set to a level where it can become toxic. Research has shown that a partial pressure of oxygen of 1.6 bar can produce acute toxicity symptoms with extended exposure.<sup id="cite_ref-Manning_2002_9-0" class="reference"><a href="#cite_note-Manning_2002-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup></li> <li>Mass loss over the dive is reduced as a much smaller amount of gas is used, so buoyancy at constant depth does not vary much as the dive progresses, and less ballast weight is needed to compensate for gas consumption.</li></ul> <div class="mw-heading mw-heading3"><h3 id="Disadvantages">Disadvantages</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=7" title="Edit section: Disadvantages"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>When compared with open circuit scuba, rebreathers have some disadvantages, including expense, complexity of operation and maintenance, and more critical paths to failure. A malfunctioning rebreather can supply a gas mixture which contains too little oxygen to sustain life, too much oxygen which may cause convulsions, or it may allow <a href="/wiki/Carbon_dioxide" title="Carbon dioxide">carbon dioxide</a> to build up to dangerous levels. Some rebreather designers try to solve these problems by monitoring the system with electronics, sensors and alarm systems. These are expensive and susceptible to failure, improper configuration and misuse.<sup id="cite_ref-Partridge2010_10-0" class="reference"><a href="#cite_note-Partridge2010-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> </p> <ul><li>Oxygen rebreathers (simple closed circuit) are limited to a shallow depth range of approximately 6 m, beyond which the risk of acute <a href="/wiki/Oxygen_toxicity" title="Oxygen toxicity">oxygen toxicity</a> rises to unacceptable levels very rapidly.</li> <li>Semi-closed circuit rebreathers are less efficient than closed circuit, and are more mechanically complex than open circuit scuba or oxygen rebreathers.</li> <li>Closed circuit rebreathers are yet more mechanically complex, and generally rely on electronic instruments and control systems to monitor and maintain a safe breathing gas mixture. This makes them more expensive to produce, more complex to maintain and test, and sensitive to getting their circuitry wet.</li> <li>Depending on the complexity of the rebreather, there are more failure modes than for open circuit scuba, and several of these failure modes are safety-critical and not easily recognized by the diver without technological intervention. A major disadvantage of a rebreather is that, due to a failure, gas may continue to be available for breathing, but the mixture provided may not support consciousness, and this may not be apparent to the user. With open circuit, this type of failure can only occur if the diver selects an unsuitable gas, and the most common type of open circuit failure, the lack of gas supply, is immediately obvious, and corrective steps like changing to an alternative supply would be taken immediately.</li></ul> <p>The <a class="mw-selflink-fragment" href="#Bailout">bailout</a> requirement of rebreather diving can sometimes require a rebreather diver to carry almost as much bulk of <a href="/wiki/Diving_cylinder" title="Diving cylinder">cylinders</a> as an open-circuit diver so the diver can complete the necessary <a href="/wiki/Decompression_stop" class="mw-redirect" title="Decompression stop">decompression stops</a> if the rebreather fails completely.<sup id="cite_ref-DIRrbBailout_11-0" class="reference"><a href="#cite_note-DIRrbBailout-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> Some rebreather divers choose not to carry enough bailout for a safe ascent breathing open circuit, but instead rely on the rebreather, believing that an irrecoverable rebreather failure is very unlikely. This practice is known as <i>alpinism</i> or <i>alpinist diving</i> and is generally deprecated due to the perceived extremely high risk of death if the rebreather fails.<sup id="cite_ref-alpinist_12-0" class="reference"><a href="#cite_note-alpinist-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Other_differences">Other differences</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=8" title="Edit section: Other differences"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>A major difference between rebreather diving and <a href="/wiki/Open-circuit_scuba" class="mw-redirect" title="Open-circuit scuba">open-circuit scuba</a> diving is in fine control of neutral buoyancy. When an open-circuit scuba diver inhales, a quantity of highly compressed gas from their cylinder is reduced in pressure by a regulator, and enters the lungs at a much higher volume than it occupied in the cylinder. This means that the diver has a tendency to rise slightly with each inhalation, and sink slightly with each exhalation. This does not happen to a rebreather diver, because the diver is circulating a roughly constant volume of gas between their lungs and the counterlung. This is not specifically an advantage or disadvantage, but it requires some practice to adjust to the difference.<sup id="cite_ref-ap_vision_5-1" class="reference"><a href="#cite_note-ap_vision-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-apdiving_1-6" class="reference"><a href="#cite_note-apdiving-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Function">Function</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=9" title="Edit section: Function"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>A rebreather functions by removing carbon dioxide from the exhaled gas, replenishing oxygen used, and providing the recycled gas at ambient pressure for the diver to inhale.<sup id="cite_ref-apdiving_1-7" class="reference"><a href="#cite_note-apdiving-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Scrubber_endurance">Scrubber endurance</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=10" title="Edit section: Scrubber endurance"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>In rebreather diving, the typical effective endurance of the scrubber will be half an hour to several hours of breathing, depending on the type and size of the scrubber, the absorbent characteristics, the ambient temperature and pressure, the operational mechanics of the rebreather, and the amount of carbon dioxide produced by the diver, which mainly depends on their <a href="/wiki/Metabolic_equivalent_of_task" title="Metabolic equivalent of task">metabolic work rate</a>.<sup id="cite_ref-Josan-Drinceanu_et_al_8-1" class="reference"><a href="#cite_note-Josan-Drinceanu_et_al-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Controlling_the_mix">Controlling the mix</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=11" title="Edit section: Controlling the mix"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>A basic need with a rebreather is to keep the <a href="/wiki/Partial_pressure" title="Partial pressure">partial pressure</a> of oxygen (<span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle P_{O_{2}}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>P</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle P_{O_{2}}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/a72ca8571542023f2367e1febc37581c12e0b1d8" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:3.81ex; height:2.843ex;" alt="{\displaystyle P_{O_{2}}}"></span>) in the mix from getting too low (causing <a href="/wiki/Hypoxia_(medical)" class="mw-redirect" title="Hypoxia (medical)">hypoxia</a>) or too high (causing <a href="/wiki/Oxygen_toxicity" title="Oxygen toxicity">oxygen toxicity</a>). In humans, the urge to breathe is normally caused by a high level of carbon dioxide in the blood, rather than lack of oxygen. If not enough new oxygen is being added, the proportion of oxygen in the loop may become too low to support consciousness, and eventually too low to support life. The resulting serious hypoxia causes sudden blackout with little or no warning. This makes <a href="/wiki/Hypoxia_(medical)" class="mw-redirect" title="Hypoxia (medical)">hypoxia</a> a deadly hazard for rebreather divers.<sup id="cite_ref-apdiving_1-8" class="reference"><a href="#cite_note-apdiving-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p><p>The method used for controlling the range of oxygen partial pressure in the breathing loop depends on the type of rebreather. </p><p>In an oxygen rebreather, once the loop has been thoroughly flushed, the mixture is effectively static at 100% oxygen, and the partial pressure is a function only of depth. In some early oxygen rebreathers the diver had to manually open and close the valve to the oxygen cylinder to refill the counter-lung each time the volume got low. In others a small continuous oxygen flow is provided by a flow restricting valve, but the set also has a manual bypass valve for descent and when consumption exceeds supply. In more advanced oxygen rebreathers, the pressure in the counter-lung controls the oxygen flow with a demand valve which will add gas when the bag is empty and internal pressure drops below ambient. </p><p>In a semi-closed rebreather the loop mix depends on a combination of factors: </p> <ul><li>the type of gas addition system and its setting, combined with the gas mixture in use, which control the rate of oxygen added. Oxygen fraction is limited by the gas mix. It can be lower but not higher.</li> <li>work rate, and therefore the oxygen consumption rate, which controls the rate of oxygen depletion, and therefore the resulting oxygen fraction.</li> <li>depth, which has the usual effect of increasing partial pressure in proportion to ambient pressure and oxygen fraction.</li></ul> <p>In manually controlled closed circuit rebreathers the diver controls the gas mix and volume in the loop by manually injecting oxygen and diluent gases to the loop and by venting the loop. The loop has a pressure relief valve to prevent damage caused by over-pressure of the loop when the mouthpiece valve is closed. </p> <figure typeof="mw:File/Frame"><a href="/wiki/File:Deepursuit.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/en/a/ac/Deepursuit.jpg" decoding="async" width="221" height="233" class="mw-file-element" data-file-width="221" data-file-height="233" /></a><figcaption>Narked at 90 Ltd – Deep Pursuit Advanced electronic rebreather controller.</figcaption></figure> <p>Electronically controlled closed-circuit rebreathers have <a href="/wiki/Electro-galvanic_oxygen_sensor" title="Electro-galvanic oxygen sensor">electro-galvanic oxygen sensors</a> which monitor the partial pressure of oxygen, and electronic control systems, which inject more oxygen to maintain the set point, and issuing an audible, visual, or vibratory warning to the diver if the partial pressure of oxygen reaches dangerously high or low levels.<sup id="cite_ref-apdiving_1-9" class="reference"><a href="#cite_note-apdiving-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p><p>The volume in the loop of both SCRs and CCRs is usually maintained by a pressure controlled <a href="/wiki/Automatic_diluent_valve" class="mw-redirect" title="Automatic diluent valve">automatic diluent valve</a>, which works on the same principle as a demand valve, to add diluent when inhalation lowers the pressure in the loop during descent or if the diver removes gas from the loop by exhaling through the nose.<sup id="cite_ref-apdiving_1-10" class="reference"><a href="#cite_note-apdiving-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading4"><h4 id="Set-points">Set-points</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=12" title="Edit section: Set-points"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>A set-point (or set point) is a factory set or user programmable limit value for the desired partial pressure of oxygen in a rebreather loop. The feedback of actual oxygen partial pressure measured by the oxygen sensors is compared with the set-points, and if it deviates outside of the limits of upper and lower set-points, the control system will activate a solenoid valve to add oxygen or diluent gas to the loop to correct the oxygen content until it is back within the set-point limits. Usually the user can override the gas addition by manual activation of injection valves.<sup id="cite_ref-ap_vision_5-2" class="reference"><a href="#cite_note-ap_vision-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-apdiving_1-11" class="reference"><a href="#cite_note-apdiving-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p><p>Some control systems allow depth activated switching of set-points, so that one pair of set-points can be selected for the main part of the dive, and another pair, usually richer, for accelerated decompression above the limiting depth. The changeover is automatic during ascent, but the high set-points are not activated before ascent as they are generally undesirable during descent and the main part of the dive.<sup id="cite_ref-ap_vision_5-3" class="reference"><a href="#cite_note-ap_vision-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-apdiving_1-12" class="reference"><a href="#cite_note-apdiving-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p><p>The deep sector set-point is chosen to minimise decompression obligation while also maintaining a low risk of oxygen toxicity over the expected dive duration. Values ranging from around 1.4 bar for a short dive to 1.0 bar for a very long dive can be used, with 1.2 to 1.3 bar being a frequent general purpose compromise. (see US Navy rebreather tables). The decompression set-point tends to be a bit higher to accelerate elimination of inert gases, while retaining a low risk of oxygen toxicity. Values between 1.4 and 1.6 bar are generally chosen, depending on the expected duration of decompression.<sup id="cite_ref-ap_vision_5-4" class="reference"><a href="#cite_note-ap_vision-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-apdiving_1-13" class="reference"><a href="#cite_note-apdiving-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Gas_endurance">Gas endurance</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=13" title="Edit section: Gas endurance"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Gas endurance depends on the amount of gas available and the control system for injection to maintain the oxygen partial pressure set points. These include constant mass flow, manual control, and automated control by injecting gas via a solenoid valve. The injection may follow the "bang-bang", "on-off", or "hysteresis" model, where the valve is activated and gas is injected until it reaches the upper set point limit, deactivated until the partial pressure reduces to the lower set point limit, and injection is started again, or more complex models such as <a href="/wiki/PID_controller" class="mw-redirect" title="PID controller">proportional-integral-derivative</a> (PID) control, in which the injection rate is controlled taking into account current rate of use, and changes to the rate of use. The gas endurance can be affected by the control model used.<sup id="cite_ref-Josan-Drinceanu_et_al_8-2" class="reference"><a href="#cite_note-Josan-Drinceanu_et_al-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Calculating_the_loop_mix">Calculating the loop mix</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=14" title="Edit section: Calculating the loop mix"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>In closed circuit rebreathers the breathing loop gas mixture is either known (100% oxygen) or monitored and controlled within set limits, by either the diver or the control circuitry, but in the case of semi-closed rebreathers, where the gas mixture depends on the predive settings and diver exertion, it is necessary to calculate the possible range of gas composition during a dive. The calculation depends on the mode of gas addition. </p> <div class="mw-heading mw-heading3"><h3 id="Oxygen_partial_pressure_in_a_semi-closed_rebreather">Oxygen partial pressure in a semi-closed rebreather</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=15" title="Edit section: Oxygen partial pressure in a semi-closed rebreather"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>A diver with a constant workload during aerobic working conditions will use an approximately constant amount of oxygen <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle V_{O_{2}}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle V_{O_{2}}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/4b8e0aca6d2e99871fd3643d73ba4cef3b42906f" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:3.673ex; height:2.843ex;" alt="{\displaystyle V_{O_{2}}}"></span> as a fraction of the respiratory minute volume (RMV, or <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle V_{E}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>E</mi> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle V_{E}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/b327692ccc05af0bf8f8fdf45b159d0e6ed849ef" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.671ex; width:2.843ex; height:2.509ex;" alt="{\displaystyle V_{E}}"></span>). This ratio of minute ventilation and oxygen uptake is the extraction ratio <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle K_{E}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>K</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>E</mi> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle K_{E}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/ead2266be5c5327587252b9f0bdcf48cdf146266" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.671ex; width:3.461ex; height:2.509ex;" alt="{\displaystyle K_{E}}"></span>, and usually falls in the range of 17 to 25 with a normal value of about 20 for healthy humans. Values as low as 10 and as high as 30 have been measured.<sup id="cite_ref-Morrison_13-0" class="reference"><a href="#cite_note-Morrison-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup> Variations may be caused by the diet of the diver and the dead space of the diver and equipment, raised levels of carbon dioxide, or raised work of breathing and tolerance to carbon dioxide. </p> <dl><dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle K_{E}={\frac {V_{E}}{V_{O_{2}}}}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>K</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>E</mi> </mrow> </msub> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>E</mi> </mrow> </msub> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> </mfrac> </mrow> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle K_{E}={\frac {V_{E}}{V_{O_{2}}}}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/254761cf57cb22de5696e65aa6aa7bcc7964407a" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.505ex; width:11.068ex; height:5.843ex;" alt="{\displaystyle K_{E}={\frac {V_{E}}{V_{O_{2}}}}}"></span> (≅20)</dd></dl> <p>Therefore, the volume of gas in the breathing circuit can be described as approximately constant, and the fresh gas addition must balance the sum of the dumped volume, the metabolically removed oxygen, and the volume change due to depth change. (metabolic carbon dioxide added to the mixture is removed by the scrubber and therefore does not affect the equation) </p> <div class="mw-heading mw-heading4"><h4 id="Constant_mass_flow">Constant mass flow</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=16" title="Edit section: Constant mass flow"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:CMF_SCR_loop_schematic.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/c/c0/CMF_SCR_loop_schematic.png/220px-CMF_SCR_loop_schematic.png" decoding="async" width="220" height="211" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/c/c0/CMF_SCR_loop_schematic.png/330px-CMF_SCR_loop_schematic.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/c/c0/CMF_SCR_loop_schematic.png/440px-CMF_SCR_loop_schematic.png 2x" data-file-width="3000" data-file-height="2881" /></a><figcaption>Loop and pneumatics schematic diagram of a typical constant mass flow semi-closed rebreather<br /> 1 Dive/surface valve with loop non-return valves<br /> 2 Exhaust hose<br /> 3 Scrubber canister (axial flow)<br /> 4 Counterlung<br /> 5 Loop overpressure valve<br /> 6 Inhalation valve<br /> 7 Breathing gas supply cylinder<br /> 8 Cylinder valve<br /> 9 Absolute pressure regulator<br /> 10 Submersible pressure gauge<br /> 11 Automatic Diluent Valve<br /> 12 Constant Mass Flow metering orifice<br /> 13 Manual bypass valve<br /> 14 Bailout demand valve</figcaption></figure> <p>Oxygen partial pressure in a constant mass flow system is controlled by the flow rate of feed gas through the orifice and the oxygen consumption of the diver. Dump rate is equal to feed rate minus oxygen consumption for this case. </p><p>The change in the fraction of oxygen <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle dF_{O_{2}loop}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>d</mi> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>l</mi> <mi>o</mi> <mi>o</mi> <mi>p</mi> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle dF_{O_{2}loop}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/5a78f0fab62bdc7cf07633056f1184cd0e63cf84" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:7.94ex; height:2.843ex;" alt="{\displaystyle dF_{O_{2}loop}}"></span> in the breathing circuit may be described by the following equation:<sup id="cite_ref-CMF_14-0" class="reference"><a href="#cite_note-CMF-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup> </p><p><span class="mwe-math-element"><span class="mwe-math-mathml-display mwe-math-mathml-a11y" style="display: none;"><math display="block" xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle V_{loop}\times dF_{O_{2}loop}=(Q_{feed}\times F_{O_{2}feed}-V_{O_{2}}-(Q_{feed}-V_{O_{2}})\times F_{O_{2}loop})dt}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>l</mi> <mi>o</mi> <mi>o</mi> <mi>p</mi> </mrow> </msub> <mo>×</mo> <mi>d</mi> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>l</mi> <mi>o</mi> <mi>o</mi> <mi>p</mi> </mrow> </msub> <mo>=</mo> <mo stretchy="false">(</mo> <msub> <mi>Q</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>f</mi> <mi>e</mi> <mi>e</mi> <mi>d</mi> </mrow> </msub> <mo>×</mo> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>f</mi> <mi>e</mi> <mi>e</mi> <mi>d</mi> </mrow> </msub> <mo>−</mo> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> <mo>−</mo> <mo stretchy="false">(</mo> <msub> <mi>Q</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>f</mi> <mi>e</mi> <mi>e</mi> <mi>d</mi> </mrow> </msub> <mo>−</mo> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> <mo stretchy="false">)</mo> <mo>×</mo> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>l</mi> <mi>o</mi> <mi>o</mi> <mi>p</mi> </mrow> </msub> <mo stretchy="false">)</mo> <mi>d</mi> <mi>t</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle V_{loop}\times dF_{O_{2}loop}=(Q_{feed}\times F_{O_{2}feed}-V_{O_{2}}-(Q_{feed}-V_{O_{2}})\times F_{O_{2}loop})dt}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/3538862774822ba09f65ae53b44f0fbac78206cb" class="mwe-math-fallback-image-display mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:70.166ex; height:3.009ex;" alt="{\displaystyle V_{loop}\times dF_{O_{2}loop}=(Q_{feed}\times F_{O_{2}feed}-V_{O_{2}}-(Q_{feed}-V_{O_{2}})\times F_{O_{2}loop})dt}"></span> </p><p>Where: </p> <dl><dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle V_{loop}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>l</mi> <mi>o</mi> <mi>o</mi> <mi>p</mi> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle V_{loop}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/6cc45baa0ed64f0205c623a7560ba2d054f9a6e2" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:4.499ex; height:2.843ex;" alt="{\displaystyle V_{loop}}"></span> = volume of the breathing circuit</dd> <dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle Q_{feed}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>Q</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>f</mi> <mi>e</mi> <mi>e</mi> <mi>d</mi> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle Q_{feed}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/3dbbd05e6e0bef7e1297714b46ad743ce1d72af2" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:5.367ex; height:2.843ex;" alt="{\displaystyle Q_{feed}}"></span> = flow rate of the fresh gas supplied by the orifice</dd> <dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle F_{O_{2}feed}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>f</mi> <mi>e</mi> <mi>e</mi> <mi>d</mi> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle F_{O_{2}feed}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/dfdfee7dfc2de47db471e54835277fea88c12db3" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:7.108ex; height:2.843ex;" alt="{\displaystyle F_{O_{2}feed}}"></span> = oxygen fraction of the supply gas</dd> <dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle V_{O_{2}}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle V_{O_{2}}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/4b8e0aca6d2e99871fd3643d73ba4cef3b42906f" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:3.673ex; height:2.843ex;" alt="{\displaystyle V_{O_{2}}}"></span> = oxygen uptake flow rate of the diver</dd></dl> <p>This leads to the differential equation: </p><p><span class="mwe-math-element"><span class="mwe-math-mathml-display mwe-math-mathml-a11y" style="display: none;"><math display="block" xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle {\frac {dF_{O_{2}loop}}{dt}}={\frac {(Q_{feed}\times F_{O_{2}feed}-V_{O_{2}}(t)-(Q_{feed}-V_{O_{2}})\times F_{O_{2}loop}(t))}{V_{loop}}}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mrow> <mi>d</mi> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>l</mi> <mi>o</mi> <mi>o</mi> <mi>p</mi> </mrow> </msub> </mrow> <mrow> <mi>d</mi> <mi>t</mi> </mrow> </mfrac> </mrow> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mrow> <mo stretchy="false">(</mo> <msub> <mi>Q</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>f</mi> <mi>e</mi> <mi>e</mi> <mi>d</mi> </mrow> </msub> <mo>×</mo> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>f</mi> <mi>e</mi> <mi>e</mi> <mi>d</mi> </mrow> </msub> <mo>−</mo> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> <mo stretchy="false">(</mo> <mi>t</mi> <mo stretchy="false">)</mo> <mo>−</mo> <mo stretchy="false">(</mo> <msub> <mi>Q</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>f</mi> <mi>e</mi> <mi>e</mi> <mi>d</mi> </mrow> </msub> <mo>−</mo> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> <mo stretchy="false">)</mo> <mo>×</mo> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>l</mi> <mi>o</mi> <mi>o</mi> <mi>p</mi> </mrow> </msub> <mo stretchy="false">(</mo> <mi>t</mi> <mo stretchy="false">)</mo> <mo stretchy="false">)</mo> </mrow> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>l</mi> <mi>o</mi> <mi>o</mi> <mi>p</mi> </mrow> </msub> </mfrac> </mrow> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle {\frac {dF_{O_{2}loop}}{dt}}={\frac {(Q_{feed}\times F_{O_{2}feed}-V_{O_{2}}(t)-(Q_{feed}-V_{O_{2}})\times F_{O_{2}loop}(t))}{V_{loop}}}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/b62a00b927791196f13ce4ceee13f7932e42c6d9" class="mwe-math-fallback-image-display mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.505ex; width:67.741ex; height:6.343ex;" alt="{\displaystyle {\frac {dF_{O_{2}loop}}{dt}}={\frac {(Q_{feed}\times F_{O_{2}feed}-V_{O_{2}}(t)-(Q_{feed}-V_{O_{2}})\times F_{O_{2}loop}(t))}{V_{loop}}}}"></span> </p><p>With solution: </p><p><span class="mwe-math-element"><span class="mwe-math-mathml-display mwe-math-mathml-a11y" style="display: none;"><math display="block" xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle F_{O_{2}loop}(t)={\frac {Q_{feed}\times F_{O_{2}feed}-V_{O_{2}}}{Q_{feed}-V_{O_{2}}}}+(F_{O_{2}loop}^{start}-{\frac {Q_{feed}\times F_{O_{2}feed}-V_{O_{2}}}{Q_{feed}-V_{O_{2}}}})\times e^{-{\frac {Q_{feed}-V_{O_{2}}}{V_{loop}}}t}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>l</mi> <mi>o</mi> <mi>o</mi> <mi>p</mi> </mrow> </msub> <mo stretchy="false">(</mo> <mi>t</mi> <mo stretchy="false">)</mo> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mrow> <msub> <mi>Q</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>f</mi> <mi>e</mi> <mi>e</mi> <mi>d</mi> </mrow> </msub> <mo>×</mo> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>f</mi> <mi>e</mi> <mi>e</mi> <mi>d</mi> </mrow> </msub> <mo>−</mo> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> </mrow> <mrow> <msub> <mi>Q</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>f</mi> <mi>e</mi> <mi>e</mi> <mi>d</mi> </mrow> </msub> <mo>−</mo> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> </mrow> </mfrac> </mrow> <mo>+</mo> <mo stretchy="false">(</mo> <msubsup> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>l</mi> <mi>o</mi> <mi>o</mi> <mi>p</mi> </mrow> <mrow class="MJX-TeXAtom-ORD"> <mi>s</mi> <mi>t</mi> <mi>a</mi> <mi>r</mi> <mi>t</mi> </mrow> </msubsup> <mo>−</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mrow> <msub> <mi>Q</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>f</mi> <mi>e</mi> <mi>e</mi> <mi>d</mi> </mrow> </msub> <mo>×</mo> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>f</mi> <mi>e</mi> <mi>e</mi> <mi>d</mi> </mrow> </msub> <mo>−</mo> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> </mrow> <mrow> <msub> <mi>Q</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>f</mi> <mi>e</mi> <mi>e</mi> <mi>d</mi> </mrow> </msub> <mo>−</mo> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> </mrow> </mfrac> </mrow> <mo stretchy="false">)</mo> <mo>×</mo> <msup> <mi>e</mi> <mrow class="MJX-TeXAtom-ORD"> <mo>−</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mrow> <msub> <mi>Q</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>f</mi> <mi>e</mi> <mi>e</mi> <mi>d</mi> </mrow> </msub> <mo>−</mo> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> </mrow> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>l</mi> <mi>o</mi> <mi>o</mi> <mi>p</mi> </mrow> </msub> </mfrac> </mrow> <mi>t</mi> </mrow> </msup> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle F_{O_{2}loop}(t)={\frac {Q_{feed}\times F_{O_{2}feed}-V_{O_{2}}}{Q_{feed}-V_{O_{2}}}}+(F_{O_{2}loop}^{start}-{\frac {Q_{feed}\times F_{O_{2}feed}-V_{O_{2}}}{Q_{feed}-V_{O_{2}}}})\times e^{-{\frac {Q_{feed}-V_{O_{2}}}{V_{loop}}}t}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/260a0c59dbc6fac64de11cb6af5442e2cfcd1129" class="mwe-math-fallback-image-display mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.671ex; width:86.513ex; height:7.509ex;" alt="{\displaystyle F_{O_{2}loop}(t)={\frac {Q_{feed}\times F_{O_{2}feed}-V_{O_{2}}}{Q_{feed}-V_{O_{2}}}}+(F_{O_{2}loop}^{start}-{\frac {Q_{feed}\times F_{O_{2}feed}-V_{O_{2}}}{Q_{feed}-V_{O_{2}}}})\times e^{-{\frac {Q_{feed}-V_{O_{2}}}{V_{loop}}}t}}"></span> </p><p>Which comprises a steady state and a transient term. </p><p>The steady state term is sufficient for most calculations: </p><p>The steady state oxygen fraction in the breathing circuit, <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle F_{O_{2}loop}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>l</mi> <mi>o</mi> <mi>o</mi> <mi>p</mi> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle F_{O_{2}loop}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/c48016ff85d812c416afae2e720bbf2367f8bf23" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:6.724ex; height:2.843ex;" alt="{\displaystyle F_{O_{2}loop}}"></span>, can be calculated from the formula:<sup id="cite_ref-CMF_14-1" class="reference"><a href="#cite_note-CMF-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup> </p><p><span class="mwe-math-element"><span class="mwe-math-mathml-display mwe-math-mathml-a11y" style="display: none;"><math display="block" xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle F_{O_{2}loop}={\frac {(Q_{feed}\times F_{O_{2}feed}-V_{O_{2}})}{(Q_{feed}-V_{O_{2}})}}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>l</mi> <mi>o</mi> <mi>o</mi> <mi>p</mi> </mrow> </msub> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mrow> <mo stretchy="false">(</mo> <msub> <mi>Q</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>f</mi> <mi>e</mi> <mi>e</mi> <mi>d</mi> </mrow> </msub> <mo>×</mo> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>f</mi> <mi>e</mi> <mi>e</mi> <mi>d</mi> </mrow> </msub> <mo>−</mo> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> <mo stretchy="false">)</mo> </mrow> <mrow> <mo stretchy="false">(</mo> <msub> <mi>Q</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>f</mi> <mi>e</mi> <mi>e</mi> <mi>d</mi> </mrow> </msub> <mo>−</mo> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> <mo stretchy="false">)</mo> </mrow> </mfrac> </mrow> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle F_{O_{2}loop}={\frac {(Q_{feed}\times F_{O_{2}feed}-V_{O_{2}})}{(Q_{feed}-V_{O_{2}})}}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/f5ae01ccd9c5956d05e29190c225c0110c8da0cd" class="mwe-math-fallback-image-display mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.671ex; width:34.297ex; height:6.509ex;" alt="{\displaystyle F_{O_{2}loop}={\frac {(Q_{feed}\times F_{O_{2}feed}-V_{O_{2}})}{(Q_{feed}-V_{O_{2}})}}}"></span> </p><p>Where: </p> <dl><dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle Q_{feed}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>Q</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>f</mi> <mi>e</mi> <mi>e</mi> <mi>d</mi> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle Q_{feed}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/3dbbd05e6e0bef7e1297714b46ad743ce1d72af2" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:5.367ex; height:2.843ex;" alt="{\displaystyle Q_{feed}}"></span> = Flow rate of fresh gas supplied by the orifice</dd> <dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle V_{O_{2}}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle V_{O_{2}}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/4b8e0aca6d2e99871fd3643d73ba4cef3b42906f" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:3.673ex; height:2.843ex;" alt="{\displaystyle V_{O_{2}}}"></span> = Oxygen uptake flow rate of the diver</dd> <dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle F_{O_{2}feed}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>f</mi> <mi>e</mi> <mi>e</mi> <mi>d</mi> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle F_{O_{2}feed}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/dfdfee7dfc2de47db471e54835277fea88c12db3" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:7.108ex; height:2.843ex;" alt="{\displaystyle F_{O_{2}feed}}"></span> = Oxygen fraction of the supply gas</dd></dl> <p>in a consistent system of units. </p><p>As oxygen consumption is an independent variable, a fixed feed rate will give a range of possible oxygen fractions for any given depth. In the interests of safety, the range can be determined by calculating oxygen fraction for maximum and minimum oxygen consumption as well as the expected rate. </p> <div class="mw-heading mw-heading4"><h4 id="Passive_addition">Passive addition</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=17" title="Edit section: Passive addition"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Passive_addition_SCR_loop_schematic.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/a/ae/Passive_addition_SCR_loop_schematic.png/220px-Passive_addition_SCR_loop_schematic.png" decoding="async" width="220" height="270" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/a/ae/Passive_addition_SCR_loop_schematic.png/330px-Passive_addition_SCR_loop_schematic.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/a/ae/Passive_addition_SCR_loop_schematic.png/440px-Passive_addition_SCR_loop_schematic.png 2x" data-file-width="2441" data-file-height="3000" /></a><figcaption>Schematic diagram of the breathing gas circuit of a passive addition semi-closed circuit rebreather<br /> 1 Dive/surface valve with loop non-return valves<br /> 2 Exhalation hose<br /> 3 Counterlung fore-chamber<br /> 4 Non-return valve to discharge bellows<br /> 5 Discharge bellows<br /> 6 Overpressure valve<br /> 7 Main counterlung bellows<br /> 8 Addition valve<br /> 9 Scrubber (axial flow)<br /> 10 Inhalation hose<br /> 11 Breathing gas storage cylinder<br /> 12 Cylinder valve<br /> 13 Regulator first stage<br /> 14 Submersible pressure gauge<br /> 15 Bailout demand valve</figcaption></figure> <p>(non-depth-compensated, also known as Variable Volume Exhaust (VVE)<sup id="cite_ref-Nuckols_15-0" class="reference"><a href="#cite_note-Nuckols-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup>) </p><p>Oxygen partial pressure in a passive addition system is controlled by the breathing rate of the diver. Feed gas is added by a valve which is equivalent to an open circuit demand valve in function, which opens to supply gas when the counterlung is empty – the moving top plate of the counterlung works like the diaphragm of a demand valve to operate the lever opening the valve when the counterlung volume is low. The volume may be low because the internal bellows has discharged a part of the previous breath to the environment, or because an increase in depth has caused the contents to be compressed, or a combination of these causes. The oxygen used by the diver also slowly decreases the volume of gas in the loop. </p><p>The change in the fraction of oxygen <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle dF_{O_{2}loop}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>d</mi> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>l</mi> <mi>o</mi> <mi>o</mi> <mi>p</mi> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle dF_{O_{2}loop}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/5a78f0fab62bdc7cf07633056f1184cd0e63cf84" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:7.94ex; height:2.843ex;" alt="{\displaystyle dF_{O_{2}loop}}"></span> in the system may be described by the following equation:<sup id="cite_ref-DC55_16-0" class="reference"><a href="#cite_note-DC55-16"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup> </p><p><span class="mwe-math-element"><span class="mwe-math-mathml-display mwe-math-mathml-a11y" style="display: none;"><math display="block" xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle V_{loop}\times dF_{O_{2}loop}=((Q_{dump}+V_{O_{2}})\times F_{O_{2}feed}-V_{O_{2}}-Q_{dump}\times F_{O_{2}loop})dt}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>l</mi> <mi>o</mi> <mi>o</mi> <mi>p</mi> </mrow> </msub> <mo>×</mo> <mi>d</mi> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>l</mi> <mi>o</mi> <mi>o</mi> <mi>p</mi> </mrow> </msub> <mo>=</mo> <mo stretchy="false">(</mo> <mo stretchy="false">(</mo> <msub> <mi>Q</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>d</mi> <mi>u</mi> <mi>m</mi> <mi>p</mi> </mrow> </msub> <mo>+</mo> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> <mo stretchy="false">)</mo> <mo>×</mo> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>f</mi> <mi>e</mi> <mi>e</mi> <mi>d</mi> </mrow> </msub> <mo>−</mo> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> <mo>−</mo> <msub> <mi>Q</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>d</mi> <mi>u</mi> <mi>m</mi> <mi>p</mi> </mrow> </msub> <mo>×</mo> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>l</mi> <mi>o</mi> <mi>o</mi> <mi>p</mi> </mrow> </msub> <mo stretchy="false">)</mo> <mi>d</mi> <mi>t</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle V_{loop}\times dF_{O_{2}loop}=((Q_{dump}+V_{O_{2}})\times F_{O_{2}feed}-V_{O_{2}}-Q_{dump}\times F_{O_{2}loop})dt}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/2db1f46453975eb2b3a5b94a7501d2872fbbf327" class="mwe-math-fallback-image-display mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:71.713ex; height:3.009ex;" alt="{\displaystyle V_{loop}\times dF_{O_{2}loop}=((Q_{dump}+V_{O_{2}})\times F_{O_{2}feed}-V_{O_{2}}-Q_{dump}\times F_{O_{2}loop})dt}"></span> </p><p>Where: </p> <dl><dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle V_{loop}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>l</mi> <mi>o</mi> <mi>o</mi> <mi>p</mi> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle V_{loop}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/6cc45baa0ed64f0205c623a7560ba2d054f9a6e2" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:4.499ex; height:2.843ex;" alt="{\displaystyle V_{loop}}"></span> = volume of the breathing circuit</dd> <dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle F_{O_{2}loop}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>l</mi> <mi>o</mi> <mi>o</mi> <mi>p</mi> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle F_{O_{2}loop}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/c48016ff85d812c416afae2e720bbf2367f8bf23" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:6.724ex; height:2.843ex;" alt="{\displaystyle F_{O_{2}loop}}"></span> = oxygen fraction of the gas mixture in the breathing circuit</dd> <dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle Q_{dump}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>Q</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>d</mi> <mi>u</mi> <mi>m</mi> <mi>p</mi> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle Q_{dump}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/865c37d170b697e4f5b2135310c89cdf92f07a03" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:6.14ex; height:2.843ex;" alt="{\displaystyle Q_{dump}}"></span> = flow of dumped gas</dd> <dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle V_{O_{2}}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle V_{O_{2}}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/4b8e0aca6d2e99871fd3643d73ba4cef3b42906f" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:3.673ex; height:2.843ex;" alt="{\displaystyle V_{O_{2}}}"></span> = oxygen uptake rate of the diver</dd> <dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle F_{O_{2}feed}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>f</mi> <mi>e</mi> <mi>e</mi> <mi>d</mi> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle F_{O_{2}feed}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/dfdfee7dfc2de47db471e54835277fea88c12db3" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:7.108ex; height:2.843ex;" alt="{\displaystyle F_{O_{2}feed}}"></span> = oxygen fraction of the feed gas</dd></dl> <p>This leads to the differential equation: </p><p><span class="mwe-math-element"><span class="mwe-math-mathml-display mwe-math-mathml-a11y" style="display: none;"><math display="block" xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle {\frac {dF_{O_{2}loop}}{dt}}={\frac {((Q_{dump}+V_{O_{2}})\times F_{O_{2}feed}(t)-V_{O_{2}}-Q_{dump}\times F_{O_{2}loop}(t))}{V_{loop}}}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mrow> <mi>d</mi> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>l</mi> <mi>o</mi> <mi>o</mi> <mi>p</mi> </mrow> </msub> </mrow> <mrow> <mi>d</mi> <mi>t</mi> </mrow> </mfrac> </mrow> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mrow> <mo stretchy="false">(</mo> <mo stretchy="false">(</mo> <msub> <mi>Q</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>d</mi> <mi>u</mi> <mi>m</mi> <mi>p</mi> </mrow> </msub> <mo>+</mo> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> <mo stretchy="false">)</mo> <mo>×</mo> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>f</mi> <mi>e</mi> <mi>e</mi> <mi>d</mi> </mrow> </msub> <mo stretchy="false">(</mo> <mi>t</mi> <mo stretchy="false">)</mo> <mo>−</mo> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> <mo>−</mo> <msub> <mi>Q</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>d</mi> <mi>u</mi> <mi>m</mi> <mi>p</mi> </mrow> </msub> <mo>×</mo> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>l</mi> <mi>o</mi> <mi>o</mi> <mi>p</mi> </mrow> </msub> <mo stretchy="false">(</mo> <mi>t</mi> <mo stretchy="false">)</mo> <mo stretchy="false">)</mo> </mrow> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>l</mi> <mi>o</mi> <mi>o</mi> <mi>p</mi> </mrow> </msub> </mfrac> </mrow> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle {\frac {dF_{O_{2}loop}}{dt}}={\frac {((Q_{dump}+V_{O_{2}})\times F_{O_{2}feed}(t)-V_{O_{2}}-Q_{dump}\times F_{O_{2}loop}(t))}{V_{loop}}}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/f2888cb4f696faa79ffe60e1287fc97026df4fa0" class="mwe-math-fallback-image-display mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.505ex; width:69.288ex; height:6.343ex;" alt="{\displaystyle {\frac {dF_{O_{2}loop}}{dt}}={\frac {((Q_{dump}+V_{O_{2}})\times F_{O_{2}feed}(t)-V_{O_{2}}-Q_{dump}\times F_{O_{2}loop}(t))}{V_{loop}}}}"></span> </p><p>With solution: </p><p><span class="mwe-math-element"><span class="mwe-math-mathml-display mwe-math-mathml-a11y" style="display: none;"><math display="block" xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle F_{O_{2}loop}(t)={\frac {(Q_{dump}+V_{O_{2}})\times F_{O_{2}feed}-V_{O_{2}}}{Q_{dump}}}+(F_{O_{2}loop}^{start}-{\frac {(Q_{dump}+V_{O_{2}})\times F_{O_{2}feed}-V_{O_{2}}}{Q_{dump}}})\times e^{-{\frac {Q_{dump}}{V_{loop}}}t}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>l</mi> <mi>o</mi> <mi>o</mi> <mi>p</mi> </mrow> </msub> <mo stretchy="false">(</mo> <mi>t</mi> <mo stretchy="false">)</mo> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mrow> <mo stretchy="false">(</mo> <msub> <mi>Q</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>d</mi> <mi>u</mi> <mi>m</mi> <mi>p</mi> </mrow> </msub> <mo>+</mo> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> <mo stretchy="false">)</mo> <mo>×</mo> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>f</mi> <mi>e</mi> <mi>e</mi> <mi>d</mi> </mrow> </msub> <mo>−</mo> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> </mrow> <msub> <mi>Q</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>d</mi> <mi>u</mi> <mi>m</mi> <mi>p</mi> </mrow> </msub> </mfrac> </mrow> <mo>+</mo> <mo stretchy="false">(</mo> <msubsup> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>l</mi> <mi>o</mi> <mi>o</mi> <mi>p</mi> </mrow> <mrow class="MJX-TeXAtom-ORD"> <mi>s</mi> <mi>t</mi> <mi>a</mi> <mi>r</mi> <mi>t</mi> </mrow> </msubsup> <mo>−</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mrow> <mo stretchy="false">(</mo> <msub> <mi>Q</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>d</mi> <mi>u</mi> <mi>m</mi> <mi>p</mi> </mrow> </msub> <mo>+</mo> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> <mo stretchy="false">)</mo> <mo>×</mo> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>f</mi> <mi>e</mi> <mi>e</mi> <mi>d</mi> </mrow> </msub> <mo>−</mo> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> </mrow> <msub> <mi>Q</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>d</mi> <mi>u</mi> <mi>m</mi> <mi>p</mi> </mrow> </msub> </mfrac> </mrow> <mo stretchy="false">)</mo> <mo>×</mo> <msup> <mi>e</mi> <mrow class="MJX-TeXAtom-ORD"> <mo>−</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <msub> <mi>Q</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>d</mi> <mi>u</mi> <mi>m</mi> <mi>p</mi> </mrow> </msub> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>l</mi> <mi>o</mi> <mi>o</mi> <mi>p</mi> </mrow> </msub> </mfrac> </mrow> <mi>t</mi> </mrow> </msup> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle F_{O_{2}loop}(t)={\frac {(Q_{dump}+V_{O_{2}})\times F_{O_{2}feed}-V_{O_{2}}}{Q_{dump}}}+(F_{O_{2}loop}^{start}-{\frac {(Q_{dump}+V_{O_{2}})\times F_{O_{2}feed}-V_{O_{2}}}{Q_{dump}}})\times e^{-{\frac {Q_{dump}}{V_{loop}}}t}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/8a57811048432bc1c1eb4217a704ab98d4864f22" class="mwe-math-fallback-image-display mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.671ex; width:101.565ex; height:7.343ex;" alt="{\displaystyle F_{O_{2}loop}(t)={\frac {(Q_{dump}+V_{O_{2}})\times F_{O_{2}feed}-V_{O_{2}}}{Q_{dump}}}+(F_{O_{2}loop}^{start}-{\frac {(Q_{dump}+V_{O_{2}})\times F_{O_{2}feed}-V_{O_{2}}}{Q_{dump}}})\times e^{-{\frac {Q_{dump}}{V_{loop}}}t}}"></span> </p><p>Which comprises a steady state and a transient term. </p><p>The steady state term is sufficient for most calculations: </p><p><span class="mwe-math-element"><span class="mwe-math-mathml-display mwe-math-mathml-a11y" style="display: none;"><math display="block" xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle F_{O_{2}bag}(t)={\frac {(Q_{dump}+V_{O_{2}})\times F_{O_{2}feed}-V_{O_{2}}}{Q_{dump}}}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>b</mi> <mi>a</mi> <mi>g</mi> </mrow> </msub> <mo stretchy="false">(</mo> <mi>t</mi> <mo stretchy="false">)</mo> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mrow> <mo stretchy="false">(</mo> <msub> <mi>Q</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>d</mi> <mi>u</mi> <mi>m</mi> <mi>p</mi> </mrow> </msub> <mo>+</mo> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> <mo stretchy="false">)</mo> <mo>×</mo> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>f</mi> <mi>e</mi> <mi>e</mi> <mi>d</mi> </mrow> </msub> <mo>−</mo> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> </mrow> <msub> <mi>Q</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>d</mi> <mi>u</mi> <mi>m</mi> <mi>p</mi> </mrow> </msub> </mfrac> </mrow> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle F_{O_{2}bag}(t)={\frac {(Q_{dump}+V_{O_{2}})\times F_{O_{2}feed}-V_{O_{2}}}{Q_{dump}}}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/289ddf758edee7da72bd03a9b91a1a45590490fb" class="mwe-math-fallback-image-display mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.671ex; width:43.685ex; height:6.509ex;" alt="{\displaystyle F_{O_{2}bag}(t)={\frac {(Q_{dump}+V_{O_{2}})\times F_{O_{2}feed}-V_{O_{2}}}{Q_{dump}}}}"></span> </p><p>The steady state oxygen fraction in the breathing circuit, <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle F_{O_{2}loop}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>l</mi> <mi>o</mi> <mi>o</mi> <mi>p</mi> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle F_{O_{2}loop}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/c48016ff85d812c416afae2e720bbf2367f8bf23" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:6.724ex; height:2.843ex;" alt="{\displaystyle F_{O_{2}loop}}"></span>, can be calculated from the formula:<sup id="cite_ref-DC55_16-1" class="reference"><a href="#cite_note-DC55-16"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup> <span class="mwe-math-element"><span class="mwe-math-mathml-display mwe-math-mathml-a11y" style="display: none;"><math display="block" xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle F_{O_{2}loop}={\frac {(Q_{dump}+V_{O_{2}})F_{O_{2}feed}-V_{O_{2}}}{Q_{dump}}}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>l</mi> <mi>o</mi> <mi>o</mi> <mi>p</mi> </mrow> </msub> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mrow> <mo stretchy="false">(</mo> <msub> <mi>Q</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>d</mi> <mi>u</mi> <mi>m</mi> <mi>p</mi> </mrow> </msub> <mo>+</mo> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> <mo stretchy="false">)</mo> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>f</mi> <mi>e</mi> <mi>e</mi> <mi>d</mi> </mrow> </msub> <mo>−</mo> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> </mrow> <msub> <mi>Q</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>d</mi> <mi>u</mi> <mi>m</mi> <mi>p</mi> </mrow> </msub> </mfrac> </mrow> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle F_{O_{2}loop}={\frac {(Q_{dump}+V_{O_{2}})F_{O_{2}feed}-V_{O_{2}}}{Q_{dump}}}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/5a0ff3c66cac9f7756afafd92d382301a726778d" class="mwe-math-fallback-image-display mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.671ex; width:38.743ex; height:6.509ex;" alt="{\displaystyle F_{O_{2}loop}={\frac {(Q_{dump}+V_{O_{2}})F_{O_{2}feed}-V_{O_{2}}}{Q_{dump}}}}"></span> </p><p>Where: </p> <dl><dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle Q_{dump}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>Q</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>d</mi> <mi>u</mi> <mi>m</mi> <mi>p</mi> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle Q_{dump}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/865c37d170b697e4f5b2135310c89cdf92f07a03" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:6.14ex; height:2.843ex;" alt="{\displaystyle Q_{dump}}"></span> = Flow rate of gas dumped by the concentric bellows</dd> <dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle V_{O_{2}}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle V_{O_{2}}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/4b8e0aca6d2e99871fd3643d73ba4cef3b42906f" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:3.673ex; height:2.843ex;" alt="{\displaystyle V_{O_{2}}}"></span> = Oxygen uptake flow rate of the diver</dd> <dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle F_{O_{2}feed}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>f</mi> <mi>e</mi> <mi>e</mi> <mi>d</mi> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle F_{O_{2}feed}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/dfdfee7dfc2de47db471e54835277fea88c12db3" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:7.108ex; height:2.843ex;" alt="{\displaystyle F_{O_{2}feed}}"></span> = Oxygen fraction of the supply gas</dd></dl> <p>in a consistent system of units. </p><p>The gas volume dumped is related to the expired minute volume and ambient pressure, <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle P_{amb}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>P</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>a</mi> <mi>m</mi> <mi>b</mi> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle P_{amb}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/912399cfb495d84699afd5e32a4ff56026d0ab0f" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.671ex; width:4.742ex; height:2.509ex;" alt="{\displaystyle P_{amb}}"></span>: </p><p><span class="mwe-math-element"><span class="mwe-math-mathml-display mwe-math-mathml-a11y" style="display: none;"><math display="block" xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle Q_{dump}=P_{amb}\times K_{bellows}\times V_{E}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>Q</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>d</mi> <mi>u</mi> <mi>m</mi> <mi>p</mi> </mrow> </msub> <mo>=</mo> <msub> <mi>P</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>a</mi> <mi>m</mi> <mi>b</mi> </mrow> </msub> <mo>×</mo> <msub> <mi>K</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>b</mi> <mi>e</mi> <mi>l</mi> <mi>l</mi> <mi>o</mi> <mi>w</mi> <mi>s</mi> </mrow> </msub> <mo>×</mo> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>E</mi> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle Q_{dump}=P_{amb}\times K_{bellows}\times V_{E}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/41f7de2f73a7db9366dd7e5199752c1a4017c653" class="mwe-math-fallback-image-display mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:29.907ex; height:2.843ex;" alt="{\displaystyle Q_{dump}=P_{amb}\times K_{bellows}\times V_{E}}"></span> </p><p>Where: </p> <dl><dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle K_{bellows}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>K</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>b</mi> <mi>e</mi> <mi>l</mi> <mi>l</mi> <mi>o</mi> <mi>w</mi> <mi>s</mi> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle K_{bellows}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/28517e851bbba21d8d3b1e71346c60808e65705f" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.671ex; width:7.402ex; height:2.509ex;" alt="{\displaystyle K_{bellows}}"></span> = bellows ratio – the ratio between the volume of expired air in the counterlungs and the amount dumped.</dd> <dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle V_{E}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>E</mi> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle V_{E}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/b327692ccc05af0bf8f8fdf45b159d0e6ed849ef" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.671ex; width:2.843ex; height:2.509ex;" alt="{\displaystyle V_{E}}"></span> = respiratory minute volume.</dd></dl> <p>By substitution: </p><p><span class="mwe-math-element"><span class="mwe-math-mathml-display mwe-math-mathml-a11y" style="display: none;"><math display="block" xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle Q_{dump}=P_{amb}\times K_{bellows}\times K_{E}\times V_{O_{2}}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>Q</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>d</mi> <mi>u</mi> <mi>m</mi> <mi>p</mi> </mrow> </msub> <mo>=</mo> <msub> <mi>P</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>a</mi> <mi>m</mi> <mi>b</mi> </mrow> </msub> <mo>×</mo> <msub> <mi>K</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>b</mi> <mi>e</mi> <mi>l</mi> <mi>l</mi> <mi>o</mi> <mi>w</mi> <mi>s</mi> </mrow> </msub> <mo>×</mo> <msub> <mi>K</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>E</mi> </mrow> </msub> <mo>×</mo> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle Q_{dump}=P_{amb}\times K_{bellows}\times K_{E}\times V_{O_{2}}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/156e724d58e538e7b56f5b231e1a9111e6c0cd02" class="mwe-math-fallback-image-display mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:37.038ex; height:2.843ex;" alt="{\displaystyle Q_{dump}=P_{amb}\times K_{bellows}\times K_{E}\times V_{O_{2}}}"></span> </p><p>Which can be inserted into the steady state equation to give: </p><p><span class="mwe-math-element"><span class="mwe-math-mathml-display mwe-math-mathml-a11y" style="display: none;"><math display="block" xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle F_{O_{2}loop}={\frac {(P_{amb}\times K_{bellows}\times K_{E}\times V_{O_{2}}+V_{O_{2}})F_{O_{2}feed}-V_{O_{2}}}{P_{amb}\times K_{bellows}\times K_{E}\times V_{O_{2}}}}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>l</mi> <mi>o</mi> <mi>o</mi> <mi>p</mi> </mrow> </msub> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mrow> <mo stretchy="false">(</mo> <msub> <mi>P</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>a</mi> <mi>m</mi> <mi>b</mi> </mrow> </msub> <mo>×</mo> <msub> <mi>K</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>b</mi> <mi>e</mi> <mi>l</mi> <mi>l</mi> <mi>o</mi> <mi>w</mi> <mi>s</mi> </mrow> </msub> <mo>×</mo> <msub> <mi>K</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>E</mi> </mrow> </msub> <mo>×</mo> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> <mo>+</mo> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> <mo stretchy="false">)</mo> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>f</mi> <mi>e</mi> <mi>e</mi> <mi>d</mi> </mrow> </msub> <mo>−</mo> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> </mrow> <mrow> <msub> <mi>P</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>a</mi> <mi>m</mi> <mi>b</mi> </mrow> </msub> <mo>×</mo> <msub> <mi>K</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>b</mi> <mi>e</mi> <mi>l</mi> <mi>l</mi> <mi>o</mi> <mi>w</mi> <mi>s</mi> </mrow> </msub> <mo>×</mo> <msub> <mi>K</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>E</mi> </mrow> </msub> <mo>×</mo> <msub> <mi>V</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> </mrow> </mfrac> </mrow> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle F_{O_{2}loop}={\frac {(P_{amb}\times K_{bellows}\times K_{E}\times V_{O_{2}}+V_{O_{2}})F_{O_{2}feed}-V_{O_{2}}}{P_{amb}\times K_{bellows}\times K_{E}\times V_{O_{2}}}}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/14d0a9cbdd93139119bfbd799a2ff09a263ea10c" class="mwe-math-fallback-image-display mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.505ex; width:60.403ex; height:6.343ex;" alt="{\displaystyle F_{O_{2}loop}={\frac {(P_{amb}\times K_{bellows}\times K_{E}\times V_{O_{2}}+V_{O_{2}})F_{O_{2}feed}-V_{O_{2}}}{P_{amb}\times K_{bellows}\times K_{E}\times V_{O_{2}}}}}"></span> </p><p>Which simplifies to: </p><p><span class="mwe-math-element"><span class="mwe-math-mathml-display mwe-math-mathml-a11y" style="display: none;"><math display="block" xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle F_{O_{2}loop}={\frac {(P_{amb}\times K_{bellows}\times K_{E}+1)F_{O_{2}feed}-1}{P_{amb}\times K_{bellows}\times K_{E}}}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>l</mi> <mi>o</mi> <mi>o</mi> <mi>p</mi> </mrow> </msub> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mrow> <mo stretchy="false">(</mo> <msub> <mi>P</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>a</mi> <mi>m</mi> <mi>b</mi> </mrow> </msub> <mo>×</mo> <msub> <mi>K</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>b</mi> <mi>e</mi> <mi>l</mi> <mi>l</mi> <mi>o</mi> <mi>w</mi> <mi>s</mi> </mrow> </msub> <mo>×</mo> <msub> <mi>K</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>E</mi> </mrow> </msub> <mo>+</mo> <mn>1</mn> <mo stretchy="false">)</mo> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>f</mi> <mi>e</mi> <mi>e</mi> <mi>d</mi> </mrow> </msub> <mo>−</mo> <mn>1</mn> </mrow> <mrow> <msub> <mi>P</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>a</mi> <mi>m</mi> <mi>b</mi> </mrow> </msub> <mo>×</mo> <msub> <mi>K</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>b</mi> <mi>e</mi> <mi>l</mi> <mi>l</mi> <mi>o</mi> <mi>w</mi> <mi>s</mi> </mrow> </msub> <mo>×</mo> <msub> <mi>K</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>E</mi> </mrow> </msub> </mrow> </mfrac> </mrow> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle F_{O_{2}loop}={\frac {(P_{amb}\times K_{bellows}\times K_{E}+1)F_{O_{2}feed}-1}{P_{amb}\times K_{bellows}\times K_{E}}}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/8baa390c9193ea9fab81bb9d6487509dc119c5bc" class="mwe-math-fallback-image-display mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.338ex; width:48.869ex; height:6.176ex;" alt="{\displaystyle F_{O_{2}loop}={\frac {(P_{amb}\times K_{bellows}\times K_{E}+1)F_{O_{2}feed}-1}{P_{amb}\times K_{bellows}\times K_{E}}}}"></span> </p><p>In this case oxygen consumption and feed rate are strongly related, and the oxygen concentration in the loop is independent of oxygen uptake and is likely to remain within fairly close tolerances of the calculated value for a given depth. </p><p>The oxygen fraction of the gas in the circuit will approximate the feed gas more closely for greater depth. </p><p>The derivation above does not take into account the temperature difference between the lung contents at 37 °C and the breathing loop, which will normally be at a lower temperature. RMV is given in litres per minute at body temperature and ambient pressure, oxygen consumption in standard litres per minute (STP) and the total volume of the lungs and breathing loop in actual litres.<sup id="cite_ref-Nuckols_15-1" class="reference"><a href="#cite_note-Nuckols-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup> This can be corrected by using the general gas equation of state to provide values for these variables at the temperature of the gas in the circuit. The effect of the temperature corrections is generally a slightly lower value for loop gas oxygen fraction.<sup id="cite_ref-pmid21384764_17-0" class="reference"><a href="#cite_note-pmid21384764-17"><span class="cite-bracket">[</span>17<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Maximum_operating_depth">Maximum operating depth</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=18" title="Edit section: Maximum operating depth"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>MOD for a closed circuit mixed gas rebreather is usually based on the MOD of the diluent, as that is the leanest mix that can be guaranteed. After a diluent flush the gas must be breathable, and this limits MOD, but it is possible to use more than one option for diluent, and switch the gas to a hypoxic mix for the deeper sector of a dive, and a normoxic mix for the shallower sectors. </p><p>MOD calculations for SCRs are usually based on the MOD for the full strength supply gas, as this can then be used for bailout at the full planned dive depth, and is the worst case estimate for the toxicity of the loop gas. MOD calculations can also be done for loop gas as calculated, but this is subject to variations which are not always accurately predictable. Loop gas calculated values for passive addition systems could possibly be used for working MOD calculation, and supply gas for emergency MOD given the relatively stable loop fraction in the passive addition systems, however the loop gas concentration may be closer to full strength if the diver works hard and ventilation increases beyond the linear extraction ratio. </p> <div class="mw-heading mw-heading2"><h2 id="Safety">Safety</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=19" title="Edit section: Safety"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">See also: <a href="/wiki/Diving_safety" title="Diving safety">Diving safety</a></div> <p>The general principle of diving safety, that the diver must be able to deal with any single immediately life-threatening equipment failure without outside assistance, holds for rebreather diving. If recovery from a failure leaves the diver in a compromised position where there is a high risk of a single point failure mode which can no longer be managed by the diver, the dive should be terminated.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (April 2013)">citation needed</span></a></i>]</sup> </p><p>Rebreathers have an intrinsically higher risk of mechanical or electrical failure because of their structural and functional complexity, but this can be mitigated by good design which provides redundancy of critical items and by carrying sufficient alternative breathing gas supplies for bailout including any required decompression in case of failure. <a href="/wiki/Diving_rebreather#Fault_tolerant_design" title="Diving rebreather">Fault tolerant design</a>, designs that minimize risk of human-machine interface errors, and adequate training in procedures that deal with this area may help reduce the fatality rate.<sup id="cite_ref-Fock_2012_18-0" class="reference"><a href="#cite_note-Fock_2012-18"><span class="cite-bracket">[</span>18<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Simanek_2021_19-0" class="reference"><a href="#cite_note-Simanek_2021-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup> </p><p>Some rebreather diving safety issues can be addressed by training, others may require a change in technical diver <a href="/wiki/Safety_culture" title="Safety culture">safety culture</a>. A major safety issue is that many divers become complacent as they become more familiar with the equipment, and begin to neglect predive checklists while assembling and preparing the equipment for use – procedures which are officially part of all rebreather training programmes. There can also be a tendency to neglect post-dive maintenance, and some divers will dive knowing that there are functional problems with the unit, because they know that there is generally redundancy designed into the system. This redundancy is intended to allow a safe termination of the dive if it occurs underwater, by eliminating a critical failure point. Diving with a unit that already has a malfunction, means that there is a single critical point of failure in that unit, which could cause a life-threatening emergency if another item in the critical path were to fail. The risk may increase by orders of magnitude.<sup id="cite_ref-Menduno_2012_20-0" class="reference"><a href="#cite_note-Menduno_2012-20"><span class="cite-bracket">[</span>20<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Hazards">Hazards</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=20" title="Edit section: Hazards"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">See also: <a href="/wiki/Diving_hazards" title="Diving hazards">Diving hazards</a>, <a href="/wiki/List_of_diving_hazards_and_precautions" title="List of diving hazards and precautions">List of diving hazards and precautions</a>, and <a href="/wiki/Latent_hypoxia" title="Latent hypoxia">Latent hypoxia</a></div> <p>In addition to the risk of other <a href="/wiki/Diving_disorders" title="Diving disorders">diving disorders</a> that open circuit divers are exposed to, rebreather divers are also more exposed to hazards which are directly connected with the effectiveness and reliability of generic and specific rebreather design and construction, not necessarily with the principles of rebreathing: </p> <ul><li>Sudden blackout due to hypoxia caused by too low a <a href="/wiki/Partial_pressure" title="Partial pressure">partial pressure</a> of oxygen in the loop. A particular problem is the drop in ambient pressure caused by the ascent phase of the dive, which can reduce the partial pressure of oxygen to hypoxic levels leading to what is sometimes called <a href="/wiki/Shallow-water_blackout" title="Shallow-water blackout">shallow-water blackout</a>.<sup id="cite_ref-XRay-mag_Pridmore_21-0" class="reference"><a href="#cite_note-XRay-mag_Pridmore-21"><span class="cite-bracket">[</span>21<span class="cite-bracket">]</span></a></sup></li> <li><a href="/wiki/Seizure" title="Seizure">Seizures</a> due to <a href="/wiki/Oxygen_toxicity" title="Oxygen toxicity">oxygen toxicity</a> caused by too high a partial pressure of oxygen in the loop. This can be caused by the rise in ambient pressure caused by the descent phase of the dive, which raises the partial pressure of oxygen to hyperoxic levels. In fully closed circuit equipment, ageing <a href="/wiki/Electro-galvanic_oxygen_sensor" title="Electro-galvanic oxygen sensor">oxygen sensors</a> may become "current limited" and fail to measure high partial pressures of oxygen resulting in dangerously high oxygen levels.</li> <li>Disorientation, <a href="/wiki/Panic" title="Panic">panic</a>, headache, and <a href="/wiki/Hyperventilation" title="Hyperventilation">hyperventilation</a> due to <a href="/wiki/Hypercapnia" title="Hypercapnia">excess of carbon dioxide</a> caused by incorrect configuration, failure or inefficiency of the <a href="/wiki/Soda_lime" title="Soda lime">scrubber</a>. The scrubber must be configured so that no exhaled gas can bypass it; it must be packed and sealed correctly, and it has a limited capacity for absorption of carbon dioxide. Another problem is the diver producing carbon dioxide faster than the absorbent can handle; for example, during hard work, fast swimming, or high work of breathing caused by excessive depth for the loop configuration and gas mixture combination. The solution to this is to reduce effort and let the absorbent catch up. The scrubber efficiency may be reduced at depth where the increased concentration of other gas molecules, due to pressure, prevents some of the carbon dioxide molecules reaching the active ingredient of the scrubber before the gas gets out the far side of the absorbent stack.<sup id="cite_ref-ClarkeScrubber2013_22-0" class="reference"><a href="#cite_note-ClarkeScrubber2013-22"><span class="cite-bracket">[</span>22<span class="cite-bracket">]</span></a></sup> Low temperatures in the scrubber will also slow down the <a href="/wiki/Reaction_rate#Factors_influencing_rate_of_reaction" title="Reaction rate">reaction rate</a>. Hypercapnia in particular is known for causing cognitive impairment even well before the level at which more obvious symptoms are displayed, and this may delay bailout to a stage where it may no longer be possible for the diver to remove the mouthpiece to switch gases.<sup id="cite_ref-Mesley_2023_23-0" class="reference"><a href="#cite_note-Mesley_2023-23"><span class="cite-bracket">[</span>23<span class="cite-bracket">]</span></a></sup></li> <li>The diver should keep breathing constantly to maintain consistent gas flow at moderate flow velocities over the carbon dioxide absorbent, so the absorbent can work most effectively. Divers need to lose any skip-breathing habits that may have been developed while diving with <a href="/wiki/Open-circuit_scuba" class="mw-redirect" title="Open-circuit scuba">open-circuit</a> scuba. In closed circuit rebreathers, constant moderate breathing also has the effect of mixing the gas, preventing oxygen-rich and oxygen-lean volumes developing within the loop, which may cause unrepresentative measurement of oxygen partial pressure and consequently misleading information to the oxygen control system. The reduced maximum flow rates of deep, steady breathing both increase average dwell time in the scrubber, and resistive work of breathing.</li> <li>"Caustic cocktail" in the loop if water comes into contact with the <a href="/wiki/Soda_lime" title="Soda lime">soda lime</a> used in the <a href="/wiki/Carbon_dioxide" title="Carbon dioxide">carbon dioxide</a> scrubber. The diver is normally alerted to this by a chalky taste in the mouth. A safe response is to bail out to "open circuit" and rinse the mouth out.</li> <li>Slow low-temperature start-up of the carbon dioxide-absorbing chemical. This is a particular problem with the Chemox chemical rebreather which requires breath moisture to activate the potassium superoxide and the carbon dioxide absorption.<sup id="cite_ref-MSAchemox_24-0" class="reference"><a href="#cite_note-MSAchemox-24"><span class="cite-bracket">[</span>24<span class="cite-bracket">]</span></a></sup> A <a href="/wiki/Chemical_oxygen_generator" title="Chemical oxygen generator">chlorate candle</a> can be provided that produces enough oxygen to allow the user's breath to activate the system.<sup id="cite_ref-MSAchemox_24-1" class="reference"><a href="#cite_note-MSAchemox-24"><span class="cite-bracket">[</span>24<span class="cite-bracket">]</span></a></sup></li> <li>A breathing loop may become contaminated by pathogens if not sufficiently cleaned and disinfected between uses or between users. These pathogens may infect subsequent users. Operating manuals include instructions for cleaning and disinfection which have been tested and do not unduly harm the equipment, but are not necessarily effective on all possible pathogens.</li></ul> <div class="mw-heading mw-heading3"><h3 id="Inherent_limitations_of_the_types_of_rebreather">Inherent limitations of the types of rebreather</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=21" title="Edit section: Inherent limitations of the types of rebreather"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Each type of rebreather has limitations on safe operating range, and specific hazards inherent to the method of operation, which affect the operating range and operating procedures. </p> <div class="mw-heading mw-heading4"><h4 id="Oxygen_rebreather">Oxygen rebreather</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=22" title="Edit section: Oxygen rebreather"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Oxygen rebreathers are simple and reliable due to their simplicity. The gas mixture is known and reliable providing the loop is adequately flushed at the start of a dive and the correct gas is used. There is little that can go wrong with the function other than flooding, leaking, running out of gas, and scrubber breakthrough, all of which are obvious to the user, and there is no risk of decompression sickness, so emergency free ascent to the surface is always an option in open water. The critical limitation of the oxygen rebreather is the very shallow <a href="/wiki/Maximum_operating_depth" title="Maximum operating depth">maximum operating depth</a> limit, due to <a href="/wiki/Oxygen_toxicity" title="Oxygen toxicity">oxygen toxicity</a> considerations.<sup id="cite_ref-Lang_2001_25-0" class="reference"><a href="#cite_note-Lang_2001-25"><span class="cite-bracket">[</span>25<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading4"><h4 id="Active_addition_SCR">Active addition SCR</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=23" title="Edit section: Active addition SCR"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Active addition SCRs vary in complexity, but all operate with a breathing loop which is normally near the upper limit of its capacity. Therefore, if the gas addition system fails, the volume of gas in the loop will generally remain sufficient to provide no warning to the diver that the oxygen is depleting, and the risk of hypoxia is relatively high. </p> <div class="mw-heading mw-heading5"><h5 id="Constant_mass_flow_SCR">Constant mass flow SCR</h5><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=24" title="Edit section: Constant mass flow SCR"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Draeger_Dolphin_SCR_DSC05264.JPG" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/c/ce/Draeger_Dolphin_SCR_DSC05264.JPG/220px-Draeger_Dolphin_SCR_DSC05264.JPG" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/c/ce/Draeger_Dolphin_SCR_DSC05264.JPG/330px-Draeger_Dolphin_SCR_DSC05264.JPG 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/c/ce/Draeger_Dolphin_SCR_DSC05264.JPG/440px-Draeger_Dolphin_SCR_DSC05264.JPG 2x" data-file-width="2048" data-file-height="1536" /></a><figcaption>Scuba diver with Dräger Dolphin constant mass flow semi-closed circuit rebreather</figcaption></figure> <p>Constant mass flow addition provides the loop with added gas which is independent of depth and metabolic oxygen consumption. If the addition to make up for depth increases is disregarded, the endurance of the unit is basically fixed for a given orifice and supply gas combination. However, the oxygen partial pressure will vary depending on metabolic requirements, and this is generally predictable only within limits. The uncertain composition of the gas means that worst case estimates are usually made for both maximum operating depth and decompression considerations. Unless the gas is monitored in real time by a decompression computer with an oxygen sensor, these rebreathers have a smaller safe depth range than open circuit on the same gas, and are a disadvantage for decompression. </p><p>A specific hazard of the gas metering system is that if the orifice is partly or completely blocked, the gas in the loop will be depleted of oxygen without the diver being aware of the problem. This can result in hypoxia and unconsciousness without warning. This can be mitigated by monitoring the partial pressure in real time using an oxygen sensor, but this adds to the complexity and cost of the equipment. </p> <div class="mw-heading mw-heading5"><h5 id="Demand_controlled_SCR">Demand controlled SCR</h5><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=25" title="Edit section: Demand controlled SCR"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The principle of operation is to add a mass of oxygen that is proportional to ventilation volume. The fresh gas addition is made by controlling the pressure in a dosage chamber proportional to the counterlung bellows volume. The dosage chamber is filled with fresh gas to a pressure proportional to bellows volume, with the highest pressure when the bellows is in the empty position. When the bellows fills during exhalation, the gas is released from the dosage chamber into the breathing circuit, proportional to the volume in the bellows during exhalation, and is fully released when the bellows is full. Excess gas is dumped to the environment through the overpressure valve after the bellows is full. </p><p>There is no dosage dependency on depth or oxygen uptake. Dosage ratio is constant once the gas has been selected, and the variations remaining on oxygen fraction are due to variations in the extraction ratio. This system provides a fairly stable oxygen fraction which is a reasonable approximation of open circuit for decompression and maximum operating depth purposes. </p><p>If the gas supply to the dosage mechanism were to fail without warning, the gas addition would stop and the diver would use up the oxygen in the loop gas until it became hypoxic and the diver lost consciousness. To prevent this, a system is needed that warns the diver that there is a feed gas supply failure so the diver must take appropriate action. This can be done by purely mechanical methods. </p> <div class="mw-heading mw-heading4"><h4 id="Passive_addition_SCR">Passive addition SCR</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=26" title="Edit section: Passive addition SCR"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Passive addition relies on inhalation by the diver to trigger gas addition when the volume of gas in the breathing loop is low. This will provide warning to the diver if the addition system stops working for any reason, as the discharge system will continue to empty the loop and the diver will have a decreasing volume of gas to breathe from. This will generally provide adequate warning before hypoxia is likely. </p><p>A concentric bellows counterlung controlled gas addition mechanism relies on the full contraction of the counterlung to inject fresh gas. This works well to maintain the loop volume during descent, but may not be effective during ascent if the gas expansion in the loop due to ambient pressure reduction is fast enough to prevent the bellows from sufficiently activating the addition valve. This effect can be counteracted by a sufficiently slow ascent or frequent pauses during ascent to allow inhalation at constant depth. The severity of risk also depends on the oxygen fraction of the supply gas and the bellows ratio. </p> <div class="mw-heading mw-heading5"><h5 id="Non-depth_compensated_PASCR">Non-depth compensated PASCR</h5><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=27" title="Edit section: Non-depth compensated PASCR"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Gas extension for the non-depth compensated passive addition SCR is directly proportional to the bellows ratio – the proportion of gas that is discharged during each breath cycle. A small ratio means that the amount of gas added each cycle is small, and the gas is rebreathed more times, but it also means that more oxygen is removed from the loop gas mix, and at shallow depths the oxygen deficit compared to the supply gas concentration is large. A large bellows ratio adds a larger proportion of the breath volume as fresh gas, and this keeps the gas mix closer to supply composition at shallow depth, but uses the gas up faster. </p><p>The mechanism is mechanically simple and reliable, and not sensitive to blockage by small particles. It is more likely to leak than block, which would use gas faster, but not compromise the safety of the gas mixture. Oxygen fraction of the loop gas is considerably less than of the supply gas in shallow water, and only slightly less at deeper depths, so the safe depth range for a given supply gas is smaller than for open circuit, and the variation in oxygen concentration is also disadvantageous for decompression. Gas switching may compensate for this limitation at the expense of complexity of construction and operation. The ability to switch to open circuit in shallow depths is an option which can compensate for the reduction in oxygen content at those depth, at the expense of operational complexity and greatly increased gas use while on open circuit. This may be considered a relatively minor problem if the requirement for bailout gas is considered. The diver will be carrying the gas anyway, and using it for decompression at the end of a dive does not increase the volume requirement for dive planning. </p><p>The loop oxygen fraction is critically dependent on an accurate assumption of the extraction ratio. If this is chosen incorrectly the oxygen fraction may differ significantly from the calculated value. Very little information on variation of extraction ratio is available in easily accessible references. </p> <div class="mw-heading mw-heading5"><h5 id="Depth_compensated_PASCR">Depth compensated PASCR</h5><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=28" title="Edit section: Depth compensated PASCR"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Halcyon_PVR-BASC_P5167709.JPG" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/b/b7/Halcyon_PVR-BASC_P5167709.JPG/220px-Halcyon_PVR-BASC_P5167709.JPG" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/b7/Halcyon_PVR-BASC_P5167709.JPG/330px-Halcyon_PVR-BASC_P5167709.JPG 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/b7/Halcyon_PVR-BASC_P5167709.JPG/440px-Halcyon_PVR-BASC_P5167709.JPG 2x" data-file-width="3648" data-file-height="2736" /></a><figcaption>Halcyon PVR-BASC, a depth compensated passive addition semi-closed rebreather.</figcaption></figure> <p>Gas extension for the depth compensated passive addition rebreather is approximately proportional to metabolic usage. The volume of gas dumped by the system is, for a given depth, a fixed fraction of the volume breathed by the diver, as in the case of the non-depth-compensated system. However, this ratio is changed in inverse proportion to ambient pressure – the bellows ratio is greatest at the surface, and decreases with depth. The effect is for an amount of gas of reasonably constant mass proportion to oxygen usage to be discharged, and the same amount, on average, is supplied by the addition valve, to make up the loop volume at steady state. This is very similar to the demand controlled SCR in effect on the oxygen fraction of the loop gas, which remains nearly constant at all depths where the compensation is linear, and for aerobic levels of exercise. The limitations on this system appear to be mainly in the mechanical complexity, bulk and mass of the equipment. The linearity of depth compensation is limited by structural considerations, and below a certain depth the compensation will be less effective, and finally dissipate. However, this does not have a great effect on oxygen fraction, as the changes at those depths are already small. The slightly higher concentrations in this case are a bit nearer to the supply gas value than if the compensation was still effective. The depth compensated PASCR can provide almost identical breathing gas to open circuit over a large depth range, with a small and nearly constant oxygen fraction in the breathing gas, eliminating a major limitation of the non-compensated system at the expense of mechanical ¢complexity. </p> <div class="mw-heading mw-heading4"><h4 id="Mixed_gas_CCR">Mixed gas CCR</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=29" title="Edit section: Mixed gas CCR"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Diver_using_Inspiration_rebreather_at_the_wreck_of_the_MV_Orotava_P6308046.JPG" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/6/65/Diver_using_Inspiration_rebreather_at_the_wreck_of_the_MV_Orotava_P6308046.JPG/220px-Diver_using_Inspiration_rebreather_at_the_wreck_of_the_MV_Orotava_P6308046.JPG" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/6/65/Diver_using_Inspiration_rebreather_at_the_wreck_of_the_MV_Orotava_P6308046.JPG/330px-Diver_using_Inspiration_rebreather_at_the_wreck_of_the_MV_Orotava_P6308046.JPG 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/6/65/Diver_using_Inspiration_rebreather_at_the_wreck_of_the_MV_Orotava_P6308046.JPG/440px-Diver_using_Inspiration_rebreather_at_the_wreck_of_the_MV_Orotava_P6308046.JPG 2x" data-file-width="3648" data-file-height="2736" /></a><figcaption>Close up side view of diver using Inspiration electronically controlled closed circuit rebreather</figcaption></figure> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Diver_using_Inspiration_rebreather_at_the_wreck_of_the_MV_Orotava_P6308040.JPG" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/c/c9/Diver_using_Inspiration_rebreather_at_the_wreck_of_the_MV_Orotava_P6308040.JPG/220px-Diver_using_Inspiration_rebreather_at_the_wreck_of_the_MV_Orotava_P6308040.JPG" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/c/c9/Diver_using_Inspiration_rebreather_at_the_wreck_of_the_MV_Orotava_P6308040.JPG/330px-Diver_using_Inspiration_rebreather_at_the_wreck_of_the_MV_Orotava_P6308040.JPG 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/c/c9/Diver_using_Inspiration_rebreather_at_the_wreck_of_the_MV_Orotava_P6308040.JPG/440px-Diver_using_Inspiration_rebreather_at_the_wreck_of_the_MV_Orotava_P6308040.JPG 2x" data-file-width="3648" data-file-height="2736" /></a><figcaption>Diver using Inspiration rebreather at the wreck of the MV Orotava</figcaption></figure> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Diver_using_Inspiration_rebreather_at_the_wreck_of_the_MV_Orotava_P6308043.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/0/03/Diver_using_Inspiration_rebreather_at_the_wreck_of_the_MV_Orotava_P6308043.jpg/220px-Diver_using_Inspiration_rebreather_at_the_wreck_of_the_MV_Orotava_P6308043.jpg" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/0/03/Diver_using_Inspiration_rebreather_at_the_wreck_of_the_MV_Orotava_P6308043.jpg/330px-Diver_using_Inspiration_rebreather_at_the_wreck_of_the_MV_Orotava_P6308043.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/0/03/Diver_using_Inspiration_rebreather_at_the_wreck_of_the_MV_Orotava_P6308043.jpg/440px-Diver_using_Inspiration_rebreather_at_the_wreck_of_the_MV_Orotava_P6308043.jpg 2x" data-file-width="3648" data-file-height="2736" /></a><figcaption>Diver using Inspiration rebreather</figcaption></figure> <p>The mixed gas closed circuit rebreather can provide an optimised gas mixture for any given depth and duration, and does this with great precision and efficiency of gas usage until it fails, and there are several ways it can fail. Many of the failure modes are not easily identified by the diver without the use of sensors and alarms, and several failure modes can reduce the gas mixture to one unsuitable for supporting life. This problem can be managed by monitoring the state of the system and taking appropriate action when it diverges from the intended state. The composition of the loop gas is inherently unstable, so a control system with feedback is required. Oxygen partial pressure, which is the characteristic to be controlled, must be measured and the value provided to the control system for corrective action. The control system may be the diver or an electronic circuit. The measuring sensors are susceptible to failure for various reasons, so more than one is required, so that if one fails without warning, the diver can use the other(s) to make a controlled termination of the dive.<sup id="cite_ref-ap_vision_5-5" class="reference"><a href="#cite_note-ap_vision-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-apdiving_1-14" class="reference"><a href="#cite_note-apdiving-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading5"><h5 id="Manually_controlled_CCR">Manually controlled CCR</h5><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=30" title="Edit section: Manually controlled CCR"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The manually controlled closed circuit rebreather (MCCCR or MCCR) relies on the attention, knowledge and skill of the diver to maintain the gas mixture at the desired composition. It relies on electrochemical sensors and electronic monitoring instruments to provide the diver with the information required to make the necessary decisions and take the correct actions to control the gas mixture. The diver is required to be aware of the status of the system at all times, which increases task loading, but along with the experience, the diver develops and retains the skills of keeping the mixture within planned limits, and is well equipped to manage minor failures. The diver remains aware of the need to constantly check the status of the equipment, as this is necessary to stay alive. </p> <div class="mw-heading mw-heading5"><h5 id="Electronically_controlled_CCR">Electronically controlled CCR</h5><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=31" title="Edit section: Electronically controlled CCR"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The electronically controlled closed circuit rebreather (ECCCR or ECCR) uses electronic circuitry to monitor the status of the loop gas in real time, and to make adjustments to keep it within narrow tolerances. It is generally very effective at this function until something goes wrong. When something does go wrong the system should notify the diver of the fault so that appropriate action can be taken. Two critical malfunctions may occur which may not be noticed by the diver. </p> <ul><li>A dangerously low oxygen partial pressure (Hypoxia) will not be noticed by the diver, but if there are functioning oxygen sensors, they will usually pick this up.<sup id="cite_ref-ap_vision_5-6" class="reference"><a href="#cite_note-ap_vision-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup></li> <li>A dangerously high oxygen partial pressure is more likely to be missed, as defective sensors may still work for low concentrations, but provide inaccurate results for high partial pressures.<sup id="cite_ref-ap_vision_5-7" class="reference"><a href="#cite_note-ap_vision-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup></li></ul> <p>An insidious problem with oxygen sensor failure is when a sensor indicates a low oxygen partial pressure which is actually not low, but a sensor failure. If the diver or the control system respond to this by adding oxygen, a hyperoxic gas can be caused which may result in convulsions. To avoid this, multiple sensors are fitted to ECCCRs, so that a single cell failure does not have fatal consequences. Three or four cells are used for systems which use voting logic.<sup id="cite_ref-Simanek_2021_19-1" class="reference"><a href="#cite_note-Simanek_2021-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-ap_vision_5-8" class="reference"><a href="#cite_note-ap_vision-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> </p><p>A control circuit may fail in complex ways. If extensive testing of failure modes is not done, the user can not know what might happen if the circuit fails, and some failures may produce unexpected consequences. A failure which does not alert the user to the correct problem may have fatal consequences.<sup id="cite_ref-Simanek_2021_19-2" class="reference"><a href="#cite_note-Simanek_2021-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup> </p><p>ECCCR alarm systems may include flashing displays on handsets, flashing LEDs on <a href="/wiki/Head-up_display" title="Head-up display">head-up displays</a>, audible alarms and vibratory alarms.<sup id="cite_ref-Simanek_2021_19-3" class="reference"><a href="#cite_note-Simanek_2021-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-ap_vision_5-9" class="reference"><a href="#cite_note-ap_vision-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-apdiving_1-15" class="reference"><a href="#cite_note-apdiving-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Failure_modes">Failure modes</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=32" title="Edit section: Failure modes"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Several failure modes are common to most types of diving rebreather, and others can occur only when the specific technology is used in the rebreather. </p> <div class="mw-heading mw-heading4"><h4 id="Scrubber_failure">Scrubber failure</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=33" title="Edit section: Scrubber failure"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>There are several ways that the scrubber may fail or become less efficient: </p> <ul><li>The scrubber canister has been incorrectly packed or configured allowing the exhaled gas to bypass the absorbent. <ul><li>The absorbent must be packed tightly so that all exhaled gas comes into close contact with the granules, and the loop is designed to avoid any spaces or gaps between the absorbent and the canister walls that would let gas bypass contact with the absorbent. If the absorbent is packed loosely it can settle, and in some cases this may allow an air path to form through or around the absorbent, known as "tunnelling" or "channelling" .<sup id="cite_ref-ap_vision_5-10" class="reference"><a href="#cite_note-ap_vision-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup></li> <li>If any of the seals, such as <a href="/wiki/O-ring" title="O-ring">O-rings</a>, or spacers that prevent bypassing of the scrubber, are not cleaned or lubricated or fitted properly, gas may bypass the scrubber, or water may get into the circuit. Some rebreathers may be assembled without all the components essential for ensuring that the breathing gas passes through the scrubber, or without the absorbent, and with no way of visually checking after assembly.</li></ul></li> <li>Exhaustion of the active ingredient ("breakthrough"). When there is insufficient active ingredient left to remove the carbon dioxide at the same rate that it is produced while the gas passes through the scrubber, the concentration will begin to build up in the loop. This occurs when the reaction front reaches the far end of the absorbent. This will occur in any scrubber if used for too long.<sup id="cite_ref-ap_vision_5-11" class="reference"><a href="#cite_note-ap_vision-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup></li> <li>Partial, temporary, or conditional breakthrough: <ul><li>If dwell time is insufficient, not all of the carbon dioxide will be removed during the pass through the scrubber. This may result in a moderate increase in carbon dioxide partial pressure in the inhaled gas, which may be tolerable, but will probably increase with time as the absorbent capacity is consumed.</li> <li>When the gas mix is under pressure caused by depth, the closer proximity of the constituent molecules reduces the freedom of the carbon dioxide molecules to move around to reach the absorbent. In deeper diving, the scrubber needs to be bigger than is needed for a shallow-water or industrial oxygen rebreather, to provide longer dwell time, because of this effect.</li> <li>At low temperatures the scrubber reaction will be slower, and may not remove enough carbon dioxide if the dwell time is too short. Dwell time is a function of flow velocity, therefore breathing rate, which is largely dependent on the level of exertion by the diver, and the consequent metabolic production of carbon dioxide. A combination of heavy work and low temperature may cause partial breakthrough in a scrubber that would function adequately at higher temperature and lower exertion, and this effect will increase as the absorbent is used up.<sup id="cite_ref-Josan-Drinceanu_et_al_8-3" class="reference"><a href="#cite_note-Josan-Drinceanu_et_al-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup></li></ul></li> <li>In below-freezing environments, wet scrubber chemicals can freeze when the rebreather is not being used, thus preventing carbon dioxide from reaching the scrubber material until warmed up.</li> <li>Scrubber flooding can cause a "caustic cocktail" – Carbon dioxide absorbent materials are <a href="/wiki/Corrosive_substance" class="mw-redirect" title="Corrosive substance">caustic</a> and can cause burns to the eyes and skin. A caustic cocktail is a mixture of water and absorbent that occurs when the scrubber floods. It produces a watery liquid with a chalky taste, which should prompt the diver to switch to an alternative source of <a href="/wiki/Breathing_gas" title="Breathing gas">breathing gas</a> and rinse his or her mouth out with water. Many modern diving rebreather absorbents are designed not to produce "cocktail" if they get wet. Excess water in the absorbent can also increase the resistance to gas flow through the breathing loop, raising the work of breathing.</li> <li>Excessive flow resistance through the breathing loop can depress the rate of breathing sufficiently to cause carbon dioxide buildup due to inadequate respiration when the required work of breathing exceeds the capacity of the diver. This is affected by gas density, loop geometry, and flow resistance in the scrubber cartridge. The scrubber may adequately remove carbon dioxide, but flow rate may be restricted so much that the diver cannot effectively circulate the breathing gas through the loop for the available effort. Whether this is technically a failure of the scrubber design, the selection of absorbent material, the selection of breathing gas, or of the rebreather as a system is open to interpretation.<sup id="cite_ref-Mitchell_2008_26-0" class="reference"><a href="#cite_note-Mitchell_2008-26"><span class="cite-bracket">[</span>26<span class="cite-bracket">]</span></a></sup></li></ul> <p>Consequences: The failure to remove carbon dioxide from the breathing gas results in a buildup of carbon dioxide leading to <a href="/wiki/Hypercapnia" title="Hypercapnia">hypercapnia</a>. This may occur gradually, over several minutes, with enough warning to the diver to bail out, or may happen in seconds, often associated with a sudden increase in depth which proportionately increases the partial pressure of the carbon dioxide, and when this happens the onset of symptoms may be so sudden and extreme that the diver is unable to control their breathing sufficiently to close and remove the DSV and swap it for a bailout regulator. This problem can be mitigated by using a bailout valve built into the rebreather mouthpiece which allows switch-over between the loop and open circuit without taking the mouthpiece out.<sup id="cite_ref-Mitchell_2008_26-1" class="reference"><a href="#cite_note-Mitchell_2008-26"><span class="cite-bracket">[</span>26<span class="cite-bracket">]</span></a></sup> </p><p>Prevention: </p> <ul><li>An indicating <a href="/wiki/Dye" title="Dye">dye</a> in the soda lime which changes the colour of the soda lime after the active ingredient is consumed may be used. For example, a rebreather absorbent called "Protosorb" supplied by <a href="/wiki/Siebe_Gorman" title="Siebe Gorman">Siebe Gorman</a> had a red dye, which was said to go white when the absorbent was exhausted. Colour indicating dye was removed from <a href="/wiki/US_Navy" class="mw-redirect" title="US Navy">US Navy</a> fleet use in 1996 when it was suspected of releasing chemicals into the circuit.<sup id="cite_ref-Lillo_et_al_1996_27-0" class="reference"><a href="#cite_note-Lillo_et_al_1996-27"><span class="cite-bracket">[</span>27<span class="cite-bracket">]</span></a></sup> With a transparent canister, this may be able to show the position of the reaction front. This is useful in dry open environments, but is not useful on diving equipment, where: <ul><li>Opening the canister to look inside would flood it with water.</li> <li>The canister is usually out of sight of the user, e.g. inside the breathing bag or inside a backpack box, or just behind the diver.</li></ul></li> <li><style data-mw-deduplicate="TemplateStyles:r1238216509">.mw-parser-output .vanchor>:target~.vanchor-text{background-color:#b1d2ff}@media screen{html.skin-theme-clientpref-night .mw-parser-output .vanchor>:target~.vanchor-text{background-color:#0f4dc9}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .vanchor>:target~.vanchor-text{background-color:#0f4dc9}}</style><span class="vanchor"><span id="Temperature_monitoring"></span><span class="vanchor-text">Temperature monitoring</span></span>. As the reaction between carbon dioxide and soda lime is exothermic, temperature sensors along the length of the scrubber can be used to measure the position of the reaction front and therefore the projected life of the scrubber. This is limited by measuring only along the line of sensors, it cannot detect bypasses or channelling.<sup id="cite_ref-Warkander_2007_28-0" class="reference"><a href="#cite_note-Warkander_2007-28"><span class="cite-bracket">[</span>28<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-AP_Diving_scrubber_monitor_29-0" class="reference"><a href="#cite_note-AP_Diving_scrubber_monitor-29"><span class="cite-bracket">[</span>29<span class="cite-bracket">]</span></a></sup></li> <li>Testing of scrubber duration limits by the manufacturer or certification authority, and specified duration limits for the unit for recommended absorbents. These limits will be conservative for most divers based on reasonably predictable levels of exertion.</li> <li>Diver training. Divers are trained to plan and monitor the exposure time of the absorbent in the scrubber and replace it within the recommended time limit. The diver must monitor the exposure of the scrubber and replace it when necessary.</li> <li>Pre-dive checks. "Prebreathing" the unit before a dive should be done for long enough to ensure that the scrubber is removing carbon dioxide, and that the concentration is not continuously rising. This test relies on the sensitivity of the diver to detect a raised concentration of carbon dioxide, which is known to be unreliable.</li> <li>Carbon dioxide gas sensors exist, such systems are not useful as a tool for monitoring scrubber life when underwater as the onset of scrubber breakthrough generally occurs quite rapidly. Such systems should be used as an essential safety device to warn divers to bail off the loop immediately.</li> <li>Scrubbers can be designed and built so that the whole reaction front does not reach the end of the canister at one time, but gradually, so that the increase of carbon dioxide concentration is gradual, and the diver gets some warning and is able to bail out before the effects are too severe.</li></ul> <p>Mitigation: The appropriate procedure for breakthrough or other scrubber failure is bailout, as there is nothing that can be done to correct the problem underwater. Scrubber breakthrough results in carbon dioxide toxicity (hypercarbia), which generally produces symptoms of a powerful, even desperate, urge to breathe. If the diver does not bail out to a breathing gas with low carbon dioxide fairly quickly, the urge to breathe may prevent removal of the mouthpiece even for the short time required to make the switch. A bailout valve integrated into the dive/surface valve or connected to the full-face mask reduces this difficulty.<sup id="cite_ref-ap_vision_5-12" class="reference"><a href="#cite_note-ap_vision-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading4"><h4 id="Oxygen_monitoring_failure">Oxygen monitoring failure</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=34" title="Edit section: Oxygen monitoring failure"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Hyperbaric_oxygen_cell_testing_pot_with_cable_connected_IMG_20201209_153728.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/b/b2/Hyperbaric_oxygen_cell_testing_pot_with_cable_connected_IMG_20201209_153728.jpg/220px-Hyperbaric_oxygen_cell_testing_pot_with_cable_connected_IMG_20201209_153728.jpg" decoding="async" width="220" height="293" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/b2/Hyperbaric_oxygen_cell_testing_pot_with_cable_connected_IMG_20201209_153728.jpg/330px-Hyperbaric_oxygen_cell_testing_pot_with_cable_connected_IMG_20201209_153728.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/b2/Hyperbaric_oxygen_cell_testing_pot_with_cable_connected_IMG_20201209_153728.jpg/440px-Hyperbaric_oxygen_cell_testing_pot_with_cable_connected_IMG_20201209_153728.jpg 2x" data-file-width="3840" data-file-height="5120" /></a><figcaption>Hyperbaric oxygen cell testing pot for testing cells at high oxygen partial pressure. This can identify cells which are starting to fail.</figcaption></figure> <p>Partial pressure monitoring of oxygen in the breathing circuit is generally done by electrochemical cells, which are sensitive to water on the cell and in the circuitry. They are also subject to gradual failure due to using up the reactive materials, and may lose sensitivity in cold conditions. Any of the failure modes may lead to inaccurate readings, without any obvious warning. Cells should be tested at the highest available oxygen partial pressure, and should be replaced after a use period and shelf life recommended by the manufacturer. </p><p>Prevention: Multiple oxygen sensors with independent circuitry reduce the risk of losing information on oxygen partial pressure. An electronically controlled CCR generally uses a minimum of three oxygen monitors to ensure that if one fails, it will be able to identify the failed cell with reasonable reliability. Use of oxygen sensor cells with different ages or histories reduces the risk of all failing at the same time, and testing the cells before a dive at oxygen partial pressure above the alarm value is likely to identify cells that are close to failing.<sup id="cite_ref-ap_vision_5-13" class="reference"><a href="#cite_note-ap_vision-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> </p><p>Mitigation: If oxygen monitoring fails, the diver can not be sure that the contents of a mixed gas CCR rebreather will sustain consciousness. Bailout is the only safe option.<sup id="cite_ref-ap_vision_5-14" class="reference"><a href="#cite_note-ap_vision-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> Oxygen monitoring is generally an optional facility on a SCR, but may be part of real time decompression calculations. Appropriate action will depend on circumstances, but this is not an immediately life-threatening event. </p> <div class="mw-heading mw-heading5"><h5 id="Managing_cell_failure_in_an_electronic_rebreather_control_system">Managing cell failure in an electronic rebreather control system</h5><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=35" title="Edit section: Managing cell failure in an electronic rebreather control system"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>If more than one statistically independent oxygen sensor cell is used, it is unlikely that more than one will fail at a time. If one assumes that only one cell will fail, then comparing three or more outputs which have been calibrated at two points is likely to pick up the cell which has failed by assuming that any two cells that produce the same output are correct and the one which produces a different output is defective. This assumption is usually correct in practice, particularly if there is some difference in the history of the cells involved.<sup id="cite_ref-30" class="reference"><a href="#cite_note-30"><span class="cite-bracket">[</span>30<span class="cite-bracket">]</span></a></sup> The concept of comparing the output from three cells at the same place in the loop and controlling the gas mixture based on the average output of the two with the most similar output at any given time is known as voting logic, and is more reliable than control based on a single cell. If the third cell output deviates sufficiently from the other two, an alarm indicates probable cell failure. If this occurs before the dive, the rebreather is deemed unsafe and should not be used. If it occurs during a dive, it indicates an unreliable control system, and the dive should be aborted. Continuing a dive using a rebreather with a failed cell alarm significantly increases the risk of a fatal loop control failure. This system is not totally reliable. There has been at least one case reported where two cells failed similarly and the control system voted out the remaining good cell.<sup id="cite_ref-Jones_2012_31-0" class="reference"><a href="#cite_note-Jones_2012-31"><span class="cite-bracket">[</span>31<span class="cite-bracket">]</span></a></sup> </p><p>If the probability of failure of each cell was statistically independent of the others, and each cell alone was sufficient to allow safe function of the rebreather, the use of three fully redundant cells in parallel would reduce risk of failure by five or six orders of magnitude.<sup id="cite_ref-Jones_2012_31-1" class="reference"><a href="#cite_note-Jones_2012-31"><span class="cite-bracket">[</span>31<span class="cite-bracket">]</span></a></sup> </p><p>The voting logic changes this considerably. A majority of cells must not fail for safe function of the unit. In order to decide whether a cell is functioning correctly, it must be compared with an expected output. This is done by comparing it against the outputs of other cells. In the case of two cells, if the outputs differ, then one at least must be wrong, but it is not known which one. In such a case the diver should assume the unit is unsafe and bail out to open circuit. With three cells, if they all differ within an accepted tolerance, they may all be deemed functional. If two differ within tolerance, and the third does not, the two within tolerance may be deemed functional, and the third faulty. If none are within tolerance of each other, they may all be faulty, and if one is not, there is no way of identifying it.<sup id="cite_ref-Jones_2012_31-2" class="reference"><a href="#cite_note-Jones_2012-31"><span class="cite-bracket">[</span>31<span class="cite-bracket">]</span></a></sup> </p><p>Using this logic, the improvement in reliability gained by use of voting logic where at least two sensors must function for the system to function is greatly reduced compared to the fully redundant version. Improvements are only in the order of one to two orders of magnitude. This would be great improvement over the single sensor, but the analysis above has assumed statistical independence of the failure of the sensors, which is generally not realistic.<sup id="cite_ref-Jones_2012_31-3" class="reference"><a href="#cite_note-Jones_2012-31"><span class="cite-bracket">[</span>31<span class="cite-bracket">]</span></a></sup> </p><p>Factors which make the cell outputs in a rebreather statistically dependent include:<sup id="cite_ref-Jones_2012_31-4" class="reference"><a href="#cite_note-Jones_2012-31"><span class="cite-bracket">[</span>31<span class="cite-bracket">]</span></a></sup> </p> <ul><li>Common calibration gas – They are all calibrated together in the pre-dive check using the same diluent and oxygen supply.</li> <li>Sensors are often from the same manufacturing batch – Components, materials and processes are likely to be very similar.</li> <li>Sensors are often installed together and have since been exposed to the same <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle P_{O_{2}}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>P</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle P_{O_{2}}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/a72ca8571542023f2367e1febc37581c12e0b1d8" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:3.81ex; height:2.843ex;" alt="{\displaystyle P_{O_{2}}}"></span> and temperature profile over the subsequent time.</li> <li>Common working environment, particularly with regards to temperature and relative humidity, as they are usually mounted in very close proximity in the loop, to ensure that they measure similar gas.</li> <li>Common measurement systems</li> <li>Common firmware for processing the signals</li></ul> <p>This statistical dependency can be minimised and mitigated by:<sup id="cite_ref-Jones_2012_31-5" class="reference"><a href="#cite_note-Jones_2012-31"><span class="cite-bracket">[</span>31<span class="cite-bracket">]</span></a></sup> </p> <ul><li>Using sensors from different manufacturers or batches, so that no two are from the same batch</li> <li>Changing sensors at different times, so they each have a different history</li> <li>Ensuring that the calibration gases are correct</li> <li>Adding a statistically independent <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle P_{O_{2}}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>P</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle P_{O_{2}}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/a72ca8571542023f2367e1febc37581c12e0b1d8" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:3.81ex; height:2.843ex;" alt="{\displaystyle P_{O_{2}}}"></span> measuring system to the loop at a different place, using a different model sensor, and using different electronics and software to process the signal.</li> <li>Calibrating this sensor using a different gas source to the others</li></ul> <p>An alternative method of providing redundancy in the control system is to recalibrate the sensors periodically during the dive by exposing them to a flow of either diluent or oxygen or both at different times, and using the output to check whether the cell is reacting appropriately to the known gas at the known depth. This method has the added advantage of allowing calibration at a higher oxygen partial pressure than 1 bar.<sup id="cite_ref-Jones_2012_31-6" class="reference"><a href="#cite_note-Jones_2012-31"><span class="cite-bracket">[</span>31<span class="cite-bracket">]</span></a></sup> This procedure may be done automatically, where the system has been designed to do it, or the diver can manually perform a <i>diluent flush</i> at any depth at which the diluent is breathable to compare the cell <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle P_{O_{2}}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>P</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle P_{O_{2}}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/a72ca8571542023f2367e1febc37581c12e0b1d8" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:3.81ex; height:2.843ex;" alt="{\displaystyle P_{O_{2}}}"></span> readings against a known <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle F_{O_{2}}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle F_{O_{2}}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/f91803021a5702db15ee2a3c584ac7c328c9392e" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:3.812ex; height:2.843ex;" alt="{\displaystyle F_{O_{2}}}"></span> and absolute pressure to verify the displayed values. This test does not only validate the cell. If the sensor does not display the expected value, it is possible that the oxygen sensor, the pressure sensor (depth), or the gas mixture <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle F_{O_{2}}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>F</mi> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>O</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle F_{O_{2}}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/f91803021a5702db15ee2a3c584ac7c328c9392e" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:3.812ex; height:2.843ex;" alt="{\displaystyle F_{O_{2}}}"></span>, or any combination of these may be faulty. As all three of these possible faults could be life-threatening, the test is quite powerful.<sup id="cite_ref-Jones_2012_31-7" class="reference"><a href="#cite_note-Jones_2012-31"><span class="cite-bracket">[</span>31<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading4"><h4 id="Gas_injection_control_circuit_failure">Gas injection control circuit failure</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=36" title="Edit section: Gas injection control circuit failure"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>If the control circuit for oxygen injection fails, the usual mode of failure results in the oxygen injection valves being closed. Unless action is taken, the breathing gas will become hypoxic with potentially fatal consequences. An alternative mode of failure is one in which the injection valves are kept open, resulting in an increasingly hyperoxic gas mix in the loop, which may pose the danger of <a href="/wiki/Oxygen_toxicity" title="Oxygen toxicity">oxygen toxicity</a>. </p><p>Prevention: Two basic approaches are possible. Either a redundant independent control system may be used, or the risk of the single system failing may be accepted, and the diver takes the responsibility for manual gas mixture control in the event of failure. </p><p>Mitigation: Most (possibly all) electronically controlled CCRs have manual injection override. If the electronic injection fails, the user can take manual control of the gas mixture provided that the oxygen monitoring is still reliably functioning. Alarms are usually provided to warn the diver of failure. </p> <div class="mw-heading mw-heading4"><h4 id="Loop_flood">Loop flood</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=37" title="Edit section: Loop flood"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The breathing resistance of a loop may more than triple if the scrubber material is flooded.<sup id="cite_ref-Deas_and_Davidov_2006_32-0" class="reference"><a href="#cite_note-Deas_and_Davidov_2006-32"><span class="cite-bracket">[</span>32<span class="cite-bracket">]</span></a></sup> The absorption of carbon dioxide by the scrubber requires a certain amount of humidity for the reaction, but an excess will degrade absorption and may lead to accelerated breakthrough. </p><p>Prevention: Predive leak checks and careful assembly are the key to avoiding leaks through connections and detecting damage. The negative pressure test is most important for this purpose. This test requires that the breathing loop maintains a pressure slightly below ambient for a few minutes to indicate that the seals will prevent leakage into the loop. Care in using the dive/surface valve will prevent flooding through the mouthpiece. This valve should always be closed when the mouthpiece is out of the mouth underwater. </p><p>Mitigation: The diver will usually be made aware of flooding by increased breathing resistance, water noise, or carbon dioxide buildup, and sometimes by buoyancy loss. A <a href="/wiki/Glossary_of_underwater_diving_terminology#caustic_cocktail" title="Glossary of underwater diving terminology">caustic cocktail</a> is usually a sign of a fairly extensive flood and is only likely if there are a lot of small particles in the scrubber material, or a relatively soluble absorbent material is used. Some rebreathers have water traps to prevent water entering through the mouthpiece from getting as far as the scrubber, and in some cases there are mechanisms to remove water from the loop while diving. Some scrubbers are virtually unaffected by water, either due to the type of absorbent medium, or due to a protective membrane.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (April 2013)">citation needed</span></a></i>]</sup> If all else fails, and the loop is flooded beyond safe functionality, the diver can bail out to open circuit. </p> <div class="mw-heading mw-heading4"><h4 id="Gas_leakage">Gas leakage</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=38" title="Edit section: Gas leakage"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>A well assembled rebreather in good condition should not leak gas from the breathing circuit into the environment except that which is required by functional considerations, such as venting during ascent, or to compensate for, or control, the addition of gas in a semi-closed rebreather.<sup id="cite_ref-ap_vision_5-15" class="reference"><a href="#cite_note-ap_vision-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> </p><p>Prevention: Pre-use preparation of the rebreather includes checking of seals and post-assembly leak checks. The positive pressure test checks that the assembled unit can maintain a slight internal positive pressure for a short period, which is an indication that gas does not leak out of the loop. Inspection and replacement of soft components should detect damage before component failure.<sup id="cite_ref-ap_vision_5-16" class="reference"><a href="#cite_note-ap_vision-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> </p><p>Mitigation: Minor gas leakage is not in itself a serious problem, but it is often a sign of damage or incorrect assembly that may later develop into a more serious problem. Manufacturer's operating manuals generally require the user to identify the cause of any leak and rectify it before using the equipment. Leaks which develop during a dive will be assessed by the dive team for cause and risk, but there is not often much that can be done about them in the water. Minor leaks may be tolerated, or the dive may be turned, depending on severity and the circumstances of the dive. A major leak may require bailout.<sup id="cite_ref-ap_vision_5-17" class="reference"><a href="#cite_note-ap_vision-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading4"><h4 id="CMF_Orifice_blockage">CMF Orifice blockage</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=39" title="Edit section: CMF Orifice blockage"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>A blockage to the constant mass flow orifice is one of the more hazardous failures of this type of semi-closed rebreather, as it will restrict the feed gas supply and may lead to a hypoxic loop gas with a high risk of the diver losing consciousness and either drowning or dry asphyxiation.. </p><p>Prevention: Inspection and flow testing of the CMF orifice before each dive or on each diving day will ensure that the orifice does not clog from corrosion, and an upstream microfilter to trap particles large enough to block the orifice will greatly reduce the risk of blockage during a dive by foreign matter in the gas supply.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (April 2013)">citation needed</span></a></i>]</sup> Some rebreathers use two orifices as this will usually ensure that at least one remains functional, and the gas is less likely to become fatally hypoxic.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (April 2013)">citation needed</span></a></i>]</sup> </p><p>Mitigation: If the oxygen content is monitored and the diver identifies a problem with feed gas delivery, it may be possible to manually add gas, or induce triggering of the automatic diluent valve by exhaling to the environment through the nose and thereby artificially reducing the volume of gas in the loop. The forced addition of gas will bring up the oxygen content, but the dive should be terminated as this problem can not be rectified during the dive. This hazard is the strongest argument for oxygen partial pressure monitoring in a CMF SCR.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (April 2013)">citation needed</span></a></i>]</sup>. </p> <div class="mw-heading mw-heading3"><h3 id="Risk">Risk</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=40" title="Edit section: Risk"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">See also: <a href="/wiki/Diving_rebreather#Fault_tolerant_design" title="Diving rebreather">Diving rebreather § Fault tolerant design</a></div> <p>The percentage of deaths that involve the use of a rebreather among US and Canadian residents increased from approximately 1 to 5% of the total diving fatalities collected by the <a href="/wiki/Divers_Alert_Network" title="Divers Alert Network">Divers Alert Network</a> from 1998 through 2004.<sup id="cite_ref-AAUS-2007_33-0" class="reference"><a href="#cite_note-AAUS-2007-33"><span class="cite-bracket">[</span>33<span class="cite-bracket">]</span></a></sup> Investigations into rebreather deaths focus on three main areas: medical, equipment, and procedural.<sup id="cite_ref-AAUS-2007_33-1" class="reference"><a href="#cite_note-AAUS-2007-33"><span class="cite-bracket">[</span>33<span class="cite-bracket">]</span></a></sup> </p><p><a href="/wiki/Divers_Alert_Network" title="Divers Alert Network">Divers Alert Network</a> (DAN) report 80 to 100 fatal accidents per 500,000 to 1 million active scuba divers in the US, per year. <a href="/wiki/British_Sub-Aqua_Club" title="British Sub-Aqua Club">British Sub-Aqua Club</a> (BSAC) and DAN open-circuit accident rates are very similar, although BSAC dives have a higher proportion of deep and decompression dives. </p><p>An analysis of 164 fatal rebreather accidents documented from 1994 to Feb 2010 by Deeplife, reports a fatal accident rate of one in 243 per year, using a conservative assumption of linear growth of rebreather use and an average of around 2500 active participants over that time. This is a fatal accident rate of over 100 times that of open circuit scuba. The statistics indicate that equipment choice has a dramatic effect on dive safety.<sup id="cite_ref-HRKP_34-0" class="reference"><a href="#cite_note-HRKP-34"><span class="cite-bracket">[</span>34<span class="cite-bracket">]</span></a></sup> </p><p>A further analysis of these rebreather deaths<sup id="cite_ref-Fock_2013_35-0" class="reference"><a href="#cite_note-Fock_2013-35"><span class="cite-bracket">[</span>35<span class="cite-bracket">]</span></a></sup> found significant inaccuracies in the original data. Review shows that the risk of death while diving on a rebreather is in the region of 5.33 deaths per 100,000 dives, roughly 10 times the risk of open circuit scuba or horseriding, five times the risk of skydiving or hang gliding, but one eighth the risk of base jumping. No significant difference was found when comparing MCCRs with ECCRs or between brands of rebreather since 2005, but accurate information on numbers of active rebreather divers and number of units sold by each manufacturer are not available. The survey also concluded that much of the increased mortality associated with CCR use may be related to use at greater than average depth for recreational diving, and to <i>high-risk behaviour</i> by the users, and that the greater complexity of CCRs makes them more prone to equipment failure than OC equipment.<sup id="cite_ref-Fock_2013_35-1" class="reference"><a href="#cite_note-Fock_2013-35"><span class="cite-bracket">[</span>35<span class="cite-bracket">]</span></a></sup> </p><p>EN 14143 (2009) (Respiratory equipment – Self-contained re-breathing diving apparatus [Authority: The European Union Per Directive 89/686/EEC]) requires that manufacturers perform a <a href="/wiki/Failure_mode,_effects,_and_criticality_analysis" title="Failure mode, effects, and criticality analysis">Failure mode, effects, and criticality analysis</a> (FMECA), but there is no requirement to publish the results, consequently most manufacturers keep their FMECA report confidential. EN 14143 also requires compliance with <a href="/wiki/IEC_61508" title="IEC 61508">EN 61508</a>. According to the Deep Life report this is not implemented by most rebreather manufacturers, with the following implications:<sup id="cite_ref-HRKP_34-1" class="reference"><a href="#cite_note-HRKP-34"><span class="cite-bracket">[</span>34<span class="cite-bracket">]</span></a></sup> </p> <ul><li>no existing rebreather has been shown to be able to tolerate any one worst case failure.</li> <li>users have no information on the safety of the equipment they use.</li> <li>the public can not examine the conclusions of FMECA and challenge dubious conclusions.</li> <li>there is no public FMECA data which can be used to develop better systems.</li></ul> <p>Analysis of probability failure trees for open circuit scuba shows that use of a parallel or <i>redundant</i> system reduces risk considerably more than improving the reliability of components in a single critical system.<sup id="cite_ref-Stone1986_36-0" class="reference"><a href="#cite_note-Stone1986-36"><span class="cite-bracket">[</span>36<span class="cite-bracket">]</span></a></sup> These risk modelling techniques were applied to CCRs, and indicated a risk of equipment failure some 23 times that for a manifolded twin cylinder open circuit set.<sup id="cite_ref-Fock_2013_35-2" class="reference"><a href="#cite_note-Fock_2013-35"><span class="cite-bracket">[</span>35<span class="cite-bracket">]</span></a></sup> When sufficient redundant breathing gas supply in the form of open circuit scuba is available, the mechanical failure risk of the combination becomes comparable to that for open circuit. This does not compensate for poor maintenance and inadequate pre-dive checks, high risk behavior, or for incorrect response to failures. Human error appears to be a major contributor to accidents.<sup id="cite_ref-Fock_2013_35-3" class="reference"><a href="#cite_note-Fock_2013-35"><span class="cite-bracket">[</span>35<span class="cite-bracket">]</span></a></sup> </p><p>There are no formal statistics on underwater electronics failure rates, but it is likely that human error is more frequent than the error rate of electronic dive computers, which are the basic component of rebreather control electronics, which process information from multiple sources and have an algorithm for controlling the oxygen injection solenoid. The sealed dive computer package has been around for long enough for the better quality models to have become reliable and robust in design and construction.<sup id="cite_ref-Simanek_2021_19-4" class="reference"><a href="#cite_note-Simanek_2021-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup> </p><p>An electronically controlled rebreather is a complex system. The control unit receives input from several sensors, evaluates the data, calculates the appropriate next action or actions, updates the system status and displays, and performs the actions, in some cases using real-time feedback to adapt the control signal.<sup id="cite_ref-Simanek_2021_19-5" class="reference"><a href="#cite_note-Simanek_2021-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup> The inputs include one or more of pressure, oxygen and temperature sensors, a clock, and possibly helium and carbon dioxide sensors. There is also a battery power source, and a user interface in the form of a visual display, and possibly audio and vibratory alarms.<sup id="cite_ref-Simanek_2021_19-6" class="reference"><a href="#cite_note-Simanek_2021-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup> </p><p>In a minimal eCCR the system is very vulnerable. A single critical fault can necessitate manual procedures for fault recovery or the need to bail out to an alternative breathing gas supply. Some faults may have fatal consequences if not noticed and managed very quickly. Critical failures include power supply, non-redundant oxygen sensor, solenoid or control unit.<sup id="cite_ref-Simanek_2021_19-7" class="reference"><a href="#cite_note-Simanek_2021-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup> </p><p>The mechanical components are relatively robust and reliable and tend to degrade non-catastrophically, and are bulky and heavy, so the electronic sensors and control systems have been the components where improved <a href="/wiki/Fault_tolerance" title="Fault tolerance">fault tolerance</a> has generally been sought. Oxygen cell failures have been a particular problem, with predictably serious consequences, so the use of multiple redundancy in oxygen partial pressure monitoring has been an important area of development for improving reliability. A problem in this regard is the cost and relatively short lifespan of oxygen sensors, along with their relatively unpredictable failure, and sensitivity to the environment.<sup id="cite_ref-Simanek_2021_19-8" class="reference"><a href="#cite_note-Simanek_2021-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup> </p><p>To combine cell redundancy with monitoring circuit, control circuit and display redundancy, the cell signals should all be available to all monitoring and control circuits in normal conditions. This can be done by sharing signals at the analog or digital stage – the cell output voltage can be supplied to the input of all monitoring units, or the voltages of some cells can be supplied to each monitor, and the processed digital signals shared. The sharing of digital signals may allow easier isolation of defective components if short circuits occur. The minimum number of cells in this architecture is two per monitoring unit, with two monitoring units for redundancy, which is more than the minimum three for basic voting logic capability.<sup id="cite_ref-Simanek_2021_19-9" class="reference"><a href="#cite_note-Simanek_2021-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup> </p><p>The three aspects of a fault tolerant rebreather are hardware redundancy, robust software and a fault detection system. The software is complex and comprises several modules with their own tasks, such as oxygen partial pressure measurement, ambient pressure measurement, Oxygen injection control, decompression status calculation and the user interface of status and information display and user inputs. It is possible to separate the user interface hardware from the control and monitoring unit, in a way that allows the control system to continue to operate if the relatively vulnerable user interface is compromised.<sup id="cite_ref-Simanek_2021_19-10" class="reference"><a href="#cite_note-Simanek_2021-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup> </p><p>Diver's Alert Network found that the actual cause of death determined by a medical examiner war drowning in 94% of recreational/technical rebreather fatalities. A military rebreather accident study found that drowning following loss of consciousness only occurred in 5.5% of cases. This much lower incidence of drowning has largely been attributed to safety protocols which include the use of a mouthpiece retaining strap (MRS) to secure the airway. There may have been other significant contributory differences in the circumstances of the incidents, such as the proximity of a buddy, the decompression status of the divers and the distance to the surface.<sup id="cite_ref-RTC_MRS_37-0" class="reference"><a href="#cite_note-RTC_MRS-37"><span class="cite-bracket">[</span>37<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Mitigation">Mitigation</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=41" title="Edit section: Mitigation"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>A variety of options have been developed to reduce the risk of, and mitigate rebreather emergencies, which can be classified as equipment and procedural options.<sup id="cite_ref-Mesley_2023_23-1" class="reference"><a href="#cite_note-Mesley_2023-23"><span class="cite-bracket">[</span>23<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading4"><h4 id="Equipment_options">Equipment options</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=42" title="Edit section: Equipment options"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p><b>Mouthpiece retaining straps</b>: These are intended to prevent the mouthpiece falling out of the diver's mouth if they lose consciousness, thereby reducing the risk of drowning. The <a href="/wiki/Rebreather_Training_Council" class="mw-redirect" title="Rebreather Training Council">Rebreather Training Council</a> issued a safety guidance note recommending the use of mouthpiece retaining straps. A mouthpiece retaining strap is also a mandatory design feature for rebreathers sold in the EU and UK, following European rebreather standard EN14143:2013. The arrangement is required to be adjustable or self adjusting, and to hold the mouthpiece firmly and comfortably in the user's mouth, and to minimise ingress of water if a diver has a convulsion or loses consciousness underwater.<sup id="cite_ref-RTC_MRS_37-1" class="reference"><a href="#cite_note-RTC_MRS-37"><span class="cite-bracket">[</span>37<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Mesley_2023_23-2" class="reference"><a href="#cite_note-Mesley_2023-23"><span class="cite-bracket">[</span>23<span class="cite-bracket">]</span></a></sup> </p><p><b>Full-face masks</b>: These provide a more secure airway than mouthpiece retaining straps, but may require special arrangements for bailout. </p><p><b>Bailout valves</b>: A bailout valve that allows the diver to bai out to open circuit without removing the mouthpiece reduces the risks in a hypercapnic event, as the mouthpiece does not have to be removed to switch to open circuit, which is quick and eliminates the chance of inhaling while the airway is unprotected. This can be supplied from onboard diluent of offboard bailout cylinder, but the gas supply must be suitable for the depth. Like the mouthpiece, the BOV should be held securely by a mouthpiece retaining strap, unless mounted to a full-face mask. If provided with a quick connector, a rescuer cn connect a suitable gas for an unconscious diver while the mouthpiece remains in place, however, quick connections are a flow restriction that will decrease the performance of the open circuit demand valve, and should be tested to make sure they perform adequately at the maximum depth intended by the user. A bailout valve is also of great value in a hypercapnic incident where the diver may be unable or unwilling to shut off the DSV and insert a separate bailout demand valve, while the carbon dioxide levels are high. This is a real problem, and once in the hypercapnic feedback loop the desperate need to breathe continuously and rapidly may make it impossible to recover. A diluent flush might be enough in some cases to get carbon dioxide low enough to be able to switch.<sup id="cite_ref-Mesley_2023_23-3" class="reference"><a href="#cite_note-Mesley_2023-23"><span class="cite-bracket">[</span>23<span class="cite-bracket">]</span></a></sup> </p><p><b>Carbon dioxide monitoring</b>: Two basic methods of detecting or monitoring carbon dioxide in the breathing loop are available as of 2024. Neither is entirely satisfactory. The temperature stich monitors the advance of the reaction front in the scrubber, but only on the line of the sensors, which is not necessarily the line at which breakthrough will occur.<sup id="cite_ref-ClarkeScrubber2013_22-1" class="reference"><a href="#cite_note-ClarkeScrubber2013-22"><span class="cite-bracket">[</span>22<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Mesley_2023_23-4" class="reference"><a href="#cite_note-Mesley_2023-23"><span class="cite-bracket">[</span>23<span class="cite-bracket">]</span></a></sup> The other method is to use electronic sensors to measure carbon dioxide partial pressure at a point in the loop. One problem with this technology is that the sensors are also sensitive to water, and can give false positives. another problem is that the carbon dioxide in the loop is not always an accurate indication of hypercapnia, as the scrubbed gas can be within specification, but the diver may be building up high levels of carbon dioxide due to high work of breathing. Measuring end of exhalation peak carbon dioxide, which would catch this problem, is not yet (2023) available.<sup id="cite_ref-Mitchell_2023_38-0" class="reference"><a href="#cite_note-Mitchell_2023-38"><span class="cite-bracket">[</span>38<span class="cite-bracket">]</span></a></sup> </p><p><b>Alarms</b>: Audible, visual, and tactile alarms may be available. Usually the default is visual alrm with the options of audible buzzers and sometimes tactile vibrators. Sometimes a head-up display is available, and sometimes a head up display positioned for visibility for the buddy is available.<sup id="cite_ref-Mesley_2023_23-5" class="reference"><a href="#cite_note-Mesley_2023-23"><span class="cite-bracket">[</span>23<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading4"><h4 id="Procedural_options">Procedural options</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=43" title="Edit section: Procedural options"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Checklists: To some extent electronic checklists are becoming an integral part of eCCR startup procedure, but they are still external to a significant part of pre-dive preparation. When using a checklist, it is important that each of the checks is verified. For example, to check that a gas supply valve has been opened, it is not sufficient to merely check gauge pressure, as this will register even if the valve was subsequently closed. Operating a valve that releases pressure will indicate whether the pressure drops of remains constant with some gas loss.<sup id="cite_ref-Mesley_2023_23-6" class="reference"><a href="#cite_note-Mesley_2023-23"><span class="cite-bracket">[</span>23<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Kohler_2023_39-0" class="reference"><a href="#cite_note-Kohler_2023-39"><span class="cite-bracket">[</span>39<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Gambin_2023_40-0" class="reference"><a href="#cite_note-Gambin_2023-40"><span class="cite-bracket">[</span>40<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Statistics">Statistics</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=44" title="Edit section: Statistics"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Statistics collected and analysed by DAN suggest that rebreather diving fatalities have averaged around 20-25 per year over the period from 2013 to 2023, which is slightly higher than the previous period, but there are also more rebreather divers doing more rebreather dives. 1400 to 2300 certifications per year are estimated, and the rebreather manufacturing industry has grown considerably, though accurate production and sales figures are not available.<sup id="cite_ref-Tillmans_2023_41-0" class="reference"><a href="#cite_note-Tillmans_2023-41"><span class="cite-bracket">[</span>41<span class="cite-bracket">]</span></a></sup> </p><p>Cardiac events, hypoxia, and hyperoxia are the main causes of death where it is known with any confidence, and fatality rates have been estimated at 1.8 to 3.8 deaths per 100,000 dives or 1.2 to 2.5 deaths per 100,000 diving hours on rebreathers.<sup id="cite_ref-Tillmans_2023_41-1" class="reference"><a href="#cite_note-Tillmans_2023-41"><span class="cite-bracket">[</span>41<span class="cite-bracket">]</span></a></sup> </p><p>The data are limited, and assumed to be underreported, particularly from Asia.<sup id="cite_ref-Tillmans_2023_41-2" class="reference"><a href="#cite_note-Tillmans_2023-41"><span class="cite-bracket">[</span>41<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading4"><h4 id="Demographics">Demographics</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=45" title="Edit section: Demographics"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading2"><h2 id="Standard_operating_procedures">Standard operating procedures</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=46" title="Edit section: Standard operating procedures"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">See also: <a href="/wiki/Scuba_skills#Basic_rebreather_diving_skills" title="Scuba skills">Scuba skills § Basic rebreather diving skills</a></div> <p>The procedures needed to use a given model of rebreather are usually detailed in the operating manual and training program for that rebreather, but there are several generic procedures which are common to all or most types. </p> <div class="mw-heading mw-heading3"><h3 id="Assembly_and_predive_function_tests">Assembly and predive function tests</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=47" title="Edit section: Assembly and predive function tests"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Before use, the scrubber canister must be filled with the correct amount of absorbent material, and the unit tested for leaks.<sup id="cite_ref-ap_vision_5-18" class="reference"><a href="#cite_note-ap_vision-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> Two leak tests are usually conducted. These are generally known as the positive and negative pressure tests, and test that the breathing loop is airtight for internal pressure slightly lower and higher than the outside. The positive pressure test checks that the unit will not lose gas while in use, and the negative pressure test ensures that water will not leak into the breathing loop where it can degrade the scrubber medium or the oxygen sensors.<sup id="cite_ref-ap_vision_5-19" class="reference"><a href="#cite_note-ap_vision-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> </p><p>A test and calibration of the oxygen sensors is part of the pre-dive or daily checks for rebreathers which use them. Electronically controlled rebreathers may have an automatic sensor check routine which compares the readings from all the cells using the diluent and pure oxygen as calibration gases. Calibration is therefore usually limited to an oxygen partial pressure of 1 bar, which is not optimal since the set points are usually more than 1 bar.<sup id="cite_ref-ap_vision_5-20" class="reference"><a href="#cite_note-ap_vision-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> To calibrate at more than one bar a special cell calibration chamber is needed, which can preferably test and calibrate the cells at 1.6 to 2 bar in pure oxygen. </p><p>Prebreathing the unit (usually for about 3 minutes) shortly before entering the water is a standard procedure. This ensures that the scrubber material gets a chance to warm up to <a href="/wiki/Operating_temperature" title="Operating temperature">operating temperature</a>, and works correctly, and that the partial pressure of oxygen in a closed-circuit rebreather is controlled correctly.<sup id="cite_ref-Deep_Life_Accident_Review_42-0" class="reference"><a href="#cite_note-Deep_Life_Accident_Review-42"><span class="cite-bracket">[</span>42<span class="cite-bracket">]</span></a></sup> Prebreathing has been found to be unreliable for checking scrubber function.<sup id="cite_ref-Graham_and_Bozanic_2012_43-0" class="reference"><a href="#cite_note-Graham_and_Bozanic_2012-43"><span class="cite-bracket">[</span>43<span class="cite-bracket">]</span></a></sup> </p> <ul class="gallery mw-gallery-packed"> <li class="gallerybox" style="width: 92px"> <div class="thumb" style="width: 90px;"><span typeof="mw:File"><a href="/wiki/File:Hyperbaric_oxygen_cell_testing_pot_with_cable_connected_IMG_20201209_153728.jpg" class="mw-file-description" title="Hyperbaric oxygen cell testing pot"><img alt="Hyperbaric oxygen cell testing pot" src="//upload.wikimedia.org/wikipedia/commons/thumb/b/b2/Hyperbaric_oxygen_cell_testing_pot_with_cable_connected_IMG_20201209_153728.jpg/135px-Hyperbaric_oxygen_cell_testing_pot_with_cable_connected_IMG_20201209_153728.jpg" decoding="async" width="90" height="120" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/b2/Hyperbaric_oxygen_cell_testing_pot_with_cable_connected_IMG_20201209_153728.jpg/202px-Hyperbaric_oxygen_cell_testing_pot_with_cable_connected_IMG_20201209_153728.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/b2/Hyperbaric_oxygen_cell_testing_pot_with_cable_connected_IMG_20201209_153728.jpg/270px-Hyperbaric_oxygen_cell_testing_pot_with_cable_connected_IMG_20201209_153728.jpg 2x" data-file-width="3840" data-file-height="5120" /></a></span></div> <div class="gallerytext">Hyperbaric oxygen cell testing pot</div> </li> <li class="gallerybox" style="width: 170px"> <div class="thumb" style="width: 168px;"><span typeof="mw:File"><a href="/wiki/File:US_Navy_040630-N-2788L-046_Hull_Maintenance_Technician_3rd_Class_Randy_McCleod,_of_Warrenton,_Miss.,_prepares_a_Mark-16_Underwater_Breathing_Apparatus.jpg" class="mw-file-description" title="Preparing for use – filling the scrubber canister with sodalime"><img alt="Preparing for use – filling the scrubber canister with sodalime" src="//upload.wikimedia.org/wikipedia/commons/thumb/c/cb/US_Navy_040630-N-2788L-046_Hull_Maintenance_Technician_3rd_Class_Randy_McCleod%2C_of_Warrenton%2C_Miss.%2C_prepares_a_Mark-16_Underwater_Breathing_Apparatus.jpg/252px-US_Navy_040630-N-2788L-046_Hull_Maintenance_Technician_3rd_Class_Randy_McCleod%2C_of_Warrenton%2C_Miss.%2C_prepares_a_Mark-16_Underwater_Breathing_Apparatus.jpg" decoding="async" width="168" height="120" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/c/cb/US_Navy_040630-N-2788L-046_Hull_Maintenance_Technician_3rd_Class_Randy_McCleod%2C_of_Warrenton%2C_Miss.%2C_prepares_a_Mark-16_Underwater_Breathing_Apparatus.jpg/378px-US_Navy_040630-N-2788L-046_Hull_Maintenance_Technician_3rd_Class_Randy_McCleod%2C_of_Warrenton%2C_Miss.%2C_prepares_a_Mark-16_Underwater_Breathing_Apparatus.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/c/cb/US_Navy_040630-N-2788L-046_Hull_Maintenance_Technician_3rd_Class_Randy_McCleod%2C_of_Warrenton%2C_Miss.%2C_prepares_a_Mark-16_Underwater_Breathing_Apparatus.jpg/504px-US_Navy_040630-N-2788L-046_Hull_Maintenance_Technician_3rd_Class_Randy_McCleod%2C_of_Warrenton%2C_Miss.%2C_prepares_a_Mark-16_Underwater_Breathing_Apparatus.jpg 2x" data-file-width="2100" data-file-height="1500" /></a></span></div> <div class="gallerytext">Preparing for use – filling the scrubber canister with sodalime</div> </li> <li class="gallerybox" style="width: 87.333333333333px"> <div class="thumb" style="width: 85.333333333333px;"><span typeof="mw:File"><a href="/wiki/File:US_Navy_100206-N-8288P-078_Sailors_assigned_to_Mobile_Diving_and_Salvage_Unit_(MDSU)_2)_and_Explosive_Ordnance_Disposal_Mobile_Unit_(EODMU)_8_submerge_a_MK-16_Mod_1_underwater_breathing_apparatus_to_check_for_leaks.jpg" class="mw-file-description" title="Immersion leak test on a Mk16"><img alt="Immersion leak test on a Mk16" src="//upload.wikimedia.org/wikipedia/commons/thumb/3/3c/US_Navy_100206-N-8288P-078_Sailors_assigned_to_Mobile_Diving_and_Salvage_Unit_%28MDSU%29_2%29_and_Explosive_Ordnance_Disposal_Mobile_Unit_%28EODMU%29_8_submerge_a_MK-16_Mod_1_underwater_breathing_apparatus_to_check_for_leaks.jpg/128px-thumbnail.jpg" decoding="async" width="86" height="120" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/3/3c/US_Navy_100206-N-8288P-078_Sailors_assigned_to_Mobile_Diving_and_Salvage_Unit_%28MDSU%29_2%29_and_Explosive_Ordnance_Disposal_Mobile_Unit_%28EODMU%29_8_submerge_a_MK-16_Mod_1_underwater_breathing_apparatus_to_check_for_leaks.jpg/193px-thumbnail.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/3/3c/US_Navy_100206-N-8288P-078_Sailors_assigned_to_Mobile_Diving_and_Salvage_Unit_%28MDSU%29_2%29_and_Explosive_Ordnance_Disposal_Mobile_Unit_%28EODMU%29_8_submerge_a_MK-16_Mod_1_underwater_breathing_apparatus_to_check_for_leaks.jpg/257px-thumbnail.jpg 2x" data-file-width="1500" data-file-height="2100" /></a></span></div> <div class="gallerytext">Immersion leak test on a Mk16</div> </li> <li class="gallerybox" style="width: 182.66666666667px"> <div class="thumb" style="width: 180.66666666667px;"><span typeof="mw:File"><a href="/wiki/File:US_Navy_090423-N-4301H-055_A_second-phase_Basic_Underwater_Demolition_SEAL(BUD-S)_candidate_checks_his_underwater_breathing_apparatus_for_ventilation_and_safety.jpg" class="mw-file-description" title="Predive positive pressure test"><img alt="Predive positive pressure test" src="//upload.wikimedia.org/wikipedia/commons/thumb/e/e3/US_Navy_090423-N-4301H-055_A_second-phase_Basic_Underwater_Demolition_SEAL%28BUD-S%29_candidate_checks_his_underwater_breathing_apparatus_for_ventilation_and_safety.jpg/271px-thumbnail.jpg" decoding="async" width="181" height="120" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/e/e3/US_Navy_090423-N-4301H-055_A_second-phase_Basic_Underwater_Demolition_SEAL%28BUD-S%29_candidate_checks_his_underwater_breathing_apparatus_for_ventilation_and_safety.jpg/407px-thumbnail.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/e/e3/US_Navy_090423-N-4301H-055_A_second-phase_Basic_Underwater_Demolition_SEAL%28BUD-S%29_candidate_checks_his_underwater_breathing_apparatus_for_ventilation_and_safety.jpg/542px-thumbnail.jpg 2x" data-file-width="4288" data-file-height="2848" /></a></span></div> <div class="gallerytext">Predive positive pressure test</div> </li> </ul> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:JJ_Rebreather_at_Blue_Rock_Quarry_PC290157.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/9/91/JJ_Rebreather_at_Blue_Rock_Quarry_PC290157.jpg/220px-JJ_Rebreather_at_Blue_Rock_Quarry_PC290157.jpg" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/9/91/JJ_Rebreather_at_Blue_Rock_Quarry_PC290157.jpg/330px-JJ_Rebreather_at_Blue_Rock_Quarry_PC290157.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/9/91/JJ_Rebreather_at_Blue_Rock_Quarry_PC290157.jpg/440px-JJ_Rebreather_at_Blue_Rock_Quarry_PC290157.jpg 2x" data-file-width="4000" data-file-height="3000" /></a><figcaption>The diver is provided with information on the status of the breathing gas in the loop on the wrist mounted display and sometimes also on a head-up display as can be seen on the mouthpiece of this JJ electronically controlled closed circuit rebreather.</figcaption></figure> <div class="mw-heading mw-heading3"><h3 id="Preventing_flooding_of_the_loop">Preventing flooding of the loop</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=48" title="Edit section: Preventing flooding of the loop"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Before the mouthpiece is removed from the mouth the dive/surface valve must be closed (or the bailout valve activated) to prevent water from flooding into the loop. This must be reversed when the mouthpiece is replaced. Operating the DSV or BOV is usually a one-hand operation when the mouthpiece is held by the teeth, but usually requires both hands if it is not in the mouth. There are no automated DSVs, only the diver can prevent flooding. </p> <div class="mw-heading mw-heading3"><h3 id="Oxygen_monitoring">Oxygen monitoring</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=49" title="Edit section: Oxygen monitoring"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Partial pressure of oxygen is of critical importance on CCRs and is monitored at frequent intervals, particularly at the start of the dive, during descent, where transient increases due to compression may occur, and during ascent, where the risk of hypoxia is highest. On electronically controlled CCRs this is done by the control system, and the diver is warned of divergence from the set point by an alarm. The diver may need to manually adjust the mixture or decrease the rate of depth change to help the injection system to correct the mix. </p> <div class="mw-heading mw-heading3"><h3 id="Monitoring_carbon_dioxide">Monitoring carbon dioxide</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=50" title="Edit section: Monitoring carbon dioxide"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Carbon dioxide buildup is also a severe hazard, and most rebreathers do not have electronic carbon dioxide monitoring, and where available, it is not entirely reliable. The diver must look out for indications of this problem at all times.<sup id="cite_ref-Deep_Life_Accident_Review_42-1" class="reference"><a href="#cite_note-Deep_Life_Accident_Review-42"><span class="cite-bracket">[</span>42<span class="cite-bracket">]</span></a></sup> A <a href="/wiki/Buddy_diver" class="mw-redirect" title="Buddy diver">buddy diver</a> should stay with a rebreather diver who is required to take emergency action until the diver has safely surfaced, as this is the time when the buddy is most likely to be needed.<sup id="cite_ref-Mesley_2023_23-7" class="reference"><a href="#cite_note-Mesley_2023-23"><span class="cite-bracket">[</span>23<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Diluent_flush">Diluent flush <span class="anchor" id="Diluent_flush"></span><span class="anchor" id="Flushing_the_loop"></span></h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=51" title="Edit section: Diluent flush"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>A "diluent flush", or "flushing the loop" procedure is a way to temporarily restore the gas mix in the loop to a known fraction of oxygen, which is known to be safe provided that the diluent is safe to breathe at the current depth. It allows the diver to compare oxygen cell readings with a known calculated partial pressure. The procedure involves simultaneously <a href="/wiki/Venting_the_rebreather_loop" class="mw-redirect" title="Venting the rebreather loop">venting the loop</a> and injecting diluent. This flushes out the old mixture and replaces it with fresh gas with a known fraction of oxygen. A diluent flush will also temporarily reduce carbon dioxide in the loop, but not for long if the scrubber is not working correctly.<sup id="cite_ref-ap_vision_5-21" class="reference"><a href="#cite_note-ap_vision-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Venting_the_loop">Venting the loop</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=52" title="Edit section: Venting the loop"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>This procedure releases gas from inside the loop to the surroundings. This is necessary to reduce pressure in the loop when ascending, and excess gas will usually be automatically released by a spring-loaded overpressure valve. Sometimes it is useful to reduce volume in the loop while it is not full, as when doing a diluent flush. There are two standard methods for dumping gas from the loop when it is not full – manually opening the dump valve, and exhaling through the nose when using a half mask. Gas will also escape from the loop if the mouthpiece is removed without closing the DSV, but this can cause the loop to flood, which is a serious malfunction.<sup id="cite_ref-ap_vision_5-22" class="reference"><a href="#cite_note-ap_vision-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Draining_the_loop">Draining the loop</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=53" title="Edit section: Draining the loop"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Regardless of whether the rebreather in question has the facility to trap any ingress of water, training on a rebreather will feature procedures for removing excess water. The method will depend on specific design of the unit, as there are a variety of places in the loop where water will accumulate which depend on the details of the loop architecture and on where the water makes ingress. Mostly these procedures will deal with water that gets in through the mouthpiece, as that is a common problem.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (May 2021)">citation needed</span></a></i>]</sup> </p> <style data-mw-deduplicate="TemplateStyles:r1251242444">.mw-parser-output .ambox{border:1px solid #a2a9b1;border-left:10px solid #36c;background-color:#fbfbfb;box-sizing:border-box}.mw-parser-output .ambox+link+.ambox,.mw-parser-output .ambox+link+style+.ambox,.mw-parser-output .ambox+link+link+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+style+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+link+.ambox{margin-top:-1px}html body.mediawiki .mw-parser-output .ambox.mbox-small-left{margin:4px 1em 4px 0;overflow:hidden;width:238px;border-collapse:collapse;font-size:88%;line-height:1.25em}.mw-parser-output .ambox-speedy{border-left:10px solid #b32424;background-color:#fee7e6}.mw-parser-output .ambox-delete{border-left:10px solid #b32424}.mw-parser-output .ambox-content{border-left:10px solid #f28500}.mw-parser-output .ambox-style{border-left:10px solid #fc3}.mw-parser-output .ambox-move{border-left:10px solid #9932cc}.mw-parser-output .ambox-protection{border-left:10px solid #a2a9b1}.mw-parser-output .ambox .mbox-text{border:none;padding:0.25em 0.5em;width:100%}.mw-parser-output .ambox .mbox-image{border:none;padding:2px 0 2px 0.5em;text-align:center}.mw-parser-output .ambox .mbox-imageright{border:none;padding:2px 0.5em 2px 0;text-align:center}.mw-parser-output .ambox .mbox-empty-cell{border:none;padding:0;width:1px}.mw-parser-output .ambox .mbox-image-div{width:52px}@media(min-width:720px){.mw-parser-output .ambox{margin:0 10%}}@media print{body.ns-0 .mw-parser-output .ambox{display:none!important}}</style><table class="box-Expand_section plainlinks metadata ambox mbox-small-left ambox-content" role="presentation"><tbody><tr><td class="mbox-image"><span typeof="mw:File"><a href="/wiki/File:Wiki_letter_w_cropped.svg" class="mw-file-description"><img alt="[icon]" src="//upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Wiki_letter_w_cropped.svg/20px-Wiki_letter_w_cropped.svg.png" decoding="async" width="20" height="14" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Wiki_letter_w_cropped.svg/30px-Wiki_letter_w_cropped.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Wiki_letter_w_cropped.svg/40px-Wiki_letter_w_cropped.svg.png 2x" data-file-width="44" data-file-height="31" /></a></span></td><td class="mbox-text"><div class="mbox-text-span">This section <b>needs expansion</b> with: different methods frequently used. You can help by <a class="external text" href="https://en.wikipedia.org/w/index.php?title=Rebreather_diving&action=edit&section=">adding to it</a>. <span class="date-container"><i>(<span class="date">May 2021</span>)</i></span></div></td></tr></tbody></table> <div class="mw-heading mw-heading3"><h3 id="Ascents_and_descents">Ascents and descents</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=54" title="Edit section: Ascents and descents"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">See also: <a href="/wiki/Ascending_and_descending_(diving)" title="Ascending and descending (diving)">Ascending and descending (diving)</a> and <a href="/wiki/Scuba_skills#Ascents_and_descents" title="Scuba skills">Scuba skills § Ascents and descents</a></div> <p>During a descent the gas in the loop is compressed by the increasing ambient opressure, and the partial pressure of oxygen will increase unless diluent is added. The gas may also compress so far that the loop structure would be collapsed unless gas is added. The <a href="/wiki/Automatic_diluent_valve" class="mw-redirect" title="Automatic diluent valve">automatic diluent valve</a>, (ADV) is used to prevent damage, and in most cases will also prevent excess oxygen partial pressure. The risk is low as failure of the ADV is usually very obvious to the diver when loop volume gets low. Reduction in loop volume also reduces buoyancy, which must be corrected along with volume in the <a href="/wiki/Buoyancy_compensator_(diving)" title="Buoyancy compensator (diving)">buoyancy compensator</a> and, if used, the <a href="/wiki/Dry_suit" title="Dry suit">dry suit</a>.<sup id="cite_ref-ap_vision_5-23" class="reference"><a href="#cite_note-ap_vision-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> </p><p>During an ascent the reduction of ambient pressure will cause the gas in the loop to expand, and excess must be vented to allow normal breathing to continue and prevent rupture of the loop. This may be done by allowing excess gas to vent through the nose, around the mouthpiece, or through an overpressure non-return valve (OPV) fitted to the loop for this purpose. A more serious hazard is the reduction in partial pressure due to the reduction in pressure, and that unless oxygen rich gas is added manually or by the control system, the loop gas may become hypoxic, with a risk of the diver losing consciousness. When the control system of an eCCR is working correctly, it will inject the correct amount of oxygen to avoid the problem, but mCCR divers must do this manually.<sup id="cite_ref-ap_vision_5-24" class="reference"><a href="#cite_note-ap_vision-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> </p><p>In a bailout rebreather, or if the DSV is closed for bailout, the automatic diluent valve and overpressure valve are necessary to prevent damage to the loop during descent and ascent.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (June 2024)">citation needed</span></a></i>]</sup> </p> <div class="mw-heading mw-heading3"><h3 id="Buoyancy_control">Buoyancy control</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=55" title="Edit section: Buoyancy control"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">See also: <a href="/wiki/Scuba_skills#Buoyancy_control" title="Scuba skills">Scuba skills § Buoyancy control</a></div> <p>Buoyancy control with a rebreather differs from open circuit in two ways. The change in mass of the diver during the dive is smaller, as less gas is used, and the change in buoyancy during a breathing cycle is negligible, so fine buoyancy adjustment by controlling the volume in the lungs does not work. This requires slightly different management techniques, and either the dry suit or buoyancy compensator must be used for buoyancy control.<sup id="cite_ref-ap_vision_5-25" class="reference"><a href="#cite_note-ap_vision-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> </p> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1251242444"><table class="box-Expand_section plainlinks metadata ambox mbox-small-left ambox-content" role="presentation"><tbody><tr><td class="mbox-image"><span typeof="mw:File"><a href="/wiki/File:Wiki_letter_w_cropped.svg" class="mw-file-description"><img alt="[icon]" src="//upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Wiki_letter_w_cropped.svg/20px-Wiki_letter_w_cropped.svg.png" decoding="async" width="20" height="14" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Wiki_letter_w_cropped.svg/30px-Wiki_letter_w_cropped.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Wiki_letter_w_cropped.svg/40px-Wiki_letter_w_cropped.svg.png 2x" data-file-width="44" data-file-height="31" /></a></span></td><td class="mbox-text"><div class="mbox-text-span">This section <b>needs expansion</b> with: Buoyancy compensator configurations used with rebreathers:Backmount, side-mount and chest mount RBs. example: Kiss Sidewinder, Draeger Ray, Libery, Inspo, RB80, others? Human factors/ergonomics. Different problems with SCRs and CCRs.. You can help by <a class="external text" href="https://en.wikipedia.org/w/index.php?title=Rebreather_diving&action=edit&section=">adding to it</a>. <span class="date-container"><i>(<span class="date">September 2024</span>)</i></span></div></td></tr></tbody></table> <div class="mw-heading mw-heading3"><h3 id="Trim">Trim</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=56" title="Edit section: Trim"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The centre of buoyancy of the lungs and counterlungs must be as close as possible for low work of breathing and good trim, so trim weights are commonly used to set up the rebreather to suit the diver.<sup id="cite_ref-ap_vision_5-26" class="reference"><a href="#cite_note-ap_vision-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Post_dive_checks,_cleaning_and_maintenance"><span id="Post_dive_checks.2C_cleaning_and_maintenance"></span>Post dive checks, cleaning and maintenance</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=57" title="Edit section: Post dive checks, cleaning and maintenance"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li>Inspection for signs of wear and damage, replacement of damaged and deteriorated components</li> <li>Rinsing with fresh water, draining, drying, and storage in well ventilated, cool, dry environment out of direct sunlight.</li> <li>Following the planned maintenance schedule. This may entail servicing by approved agents, and may require shipping to the manufacturer.</li> <li>Disposal of spent absorbent material</li> <li>Disinfection of the loop.</li> <li>Replacement of oxygen sensors.</li></ul> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1251242444"><table class="box-Expand_section plainlinks metadata ambox mbox-small-left ambox-content" role="presentation"><tbody><tr><td class="mbox-image"><span typeof="mw:File"><a href="/wiki/File:Wiki_letter_w_cropped.svg" class="mw-file-description"><img alt="[icon]" src="//upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Wiki_letter_w_cropped.svg/20px-Wiki_letter_w_cropped.svg.png" decoding="async" width="20" height="14" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Wiki_letter_w_cropped.svg/30px-Wiki_letter_w_cropped.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Wiki_letter_w_cropped.svg/40px-Wiki_letter_w_cropped.svg.png 2x" data-file-width="44" data-file-height="31" /></a></span></td><td class="mbox-text"><div class="mbox-text-span">This section <b>needs expansion</b>. You can help by <a class="external text" href="https://en.wikipedia.org/w/index.php?title=Rebreather_diving&action=edit&section=">adding to it</a>. <span class="date-container"><i>(<span class="date">May 2021</span>)</i></span></div></td></tr></tbody></table> <div class="mw-heading mw-heading2"><h2 id="Emergency_procedures">Emergency procedures</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=58" title="Edit section: Emergency procedures"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">See also: <a href="/wiki/Scuba_skills#Emergency_procedures" title="Scuba skills">Scuba skills § Emergency procedures</a></div> <p>Each possible failure mode has an associated response. Those which are more likely to occur or have serious consequences will have associated emergency procedures that are known to be effective which the diver must learn to be considered properly trained, and must be able to perform reliably under stress to be considered competent. Many of the emergency procedures of rebreather diving are identical to, or similar to, those for open circuit scuba. </p> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1251242444"><table class="box-Expand_section plainlinks metadata ambox mbox-small-left ambox-content" role="presentation"><tbody><tr><td class="mbox-image"><span typeof="mw:File"><a href="/wiki/File:Wiki_letter_w_cropped.svg" class="mw-file-description"><img alt="[icon]" src="//upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Wiki_letter_w_cropped.svg/20px-Wiki_letter_w_cropped.svg.png" decoding="async" width="20" height="14" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Wiki_letter_w_cropped.svg/30px-Wiki_letter_w_cropped.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Wiki_letter_w_cropped.svg/40px-Wiki_letter_w_cropped.svg.png 2x" data-file-width="44" data-file-height="31" /></a></span></td><td class="mbox-text"><div class="mbox-text-span">This section <b>needs expansion</b> with: other emergency procedures. You can help by <a class="external text" href="https://en.wikipedia.org/w/index.php?title=Rebreather_diving&action=edit&section=">adding to it</a>. <span class="date-container"><i>(<span class="date">February 2024</span>)</i></span></div></td></tr></tbody></table> <div class="mw-heading mw-heading3"><h3 id="Bailout">Bailout</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=59" title="Edit section: Bailout"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Trevor_Jackson_returns_from_SS_Kyogle.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/f/f8/Trevor_Jackson_returns_from_SS_Kyogle.jpg/220px-Trevor_Jackson_returns_from_SS_Kyogle.jpg" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/f8/Trevor_Jackson_returns_from_SS_Kyogle.jpg/330px-Trevor_Jackson_returns_from_SS_Kyogle.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/f8/Trevor_Jackson_returns_from_SS_Kyogle.jpg/440px-Trevor_Jackson_returns_from_SS_Kyogle.jpg 2x" data-file-width="802" data-file-height="602" /></a><figcaption>Rebreather diver with bailout and decompression cylinders</figcaption></figure> <p>While the diver is underwater, the rebreather may fail and be unable to provide a safe breathing mix for the duration of the ascent back to the surface. In this case the diver needs an alternative breathing source: the bailout system.<sup id="cite_ref-Pitkin_2023_44-0" class="reference"><a href="#cite_note-Pitkin_2023-44"><span class="cite-bracket">[</span>44<span class="cite-bracket">]</span></a></sup> </p><p>Although some rebreather divers – referred to as "<a href="/wiki/Alpine_style" class="mw-redirect" title="Alpine style">alpinists</a>" – do not carry bailout equipment, bailout strategy becomes a crucial part of dive planning, particularly for long dives and deeper dives in <a href="/wiki/Technical_diving" title="Technical diving">technical diving</a>. Often the planned dive is limited by the capacity of the bailout set and not the capacity of the rebreather. Circumstances in which bailout is necessary include loop floods, which may involve a <a href="/wiki/Caustic_cocktail" class="mw-redirect" title="Caustic cocktail">caustic cocktail</a>, and scrubber failures for other reasons, resulting in high carbon dioxide levels in the inhalation part of the loop. More than half of the divers in a survey had experienced at least one caustic cocktail, an event that renders the rebreather unfit for further use until it has been cleaned and repacked, and therefore urgently requires bailout.<sup id="cite_ref-Pitkin_2023_44-1" class="reference"><a href="#cite_note-Pitkin_2023-44"><span class="cite-bracket">[</span>44<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Buzzacott_et_al_2022_45-0" class="reference"><a href="#cite_note-Buzzacott_et_al_2022-45"><span class="cite-bracket">[</span>45<span class="cite-bracket">]</span></a></sup> </p><p>Several types of bailout are possible: </p> <ul><li>An <a href="/wiki/Scuba_set#Open_circuit" title="Scuba set">open-circuit</a> demand valve connected to the rebreather's diluent cylinder, known as bailout to diluent or "dilout". While this option can have the advantages of being permanently mounted on the rebreather and not heavy, the quantity of gas held on-board the rebreather is usually small so the protection offered is low, though with some rebreathers such as the JJ which can carry larger on-board cylinders, or any rebreather with off-board diluent, the quantity can be viable.<sup id="cite_ref-Simanek_46-0" class="reference"><a href="#cite_note-Simanek-46"><span class="cite-bracket">[</span>46<span class="cite-bracket">]</span></a></sup></li> <li>An open-circuit demand valve connected to the rebreather's oxygen cylinder. This is similar to the open circuit diluent bailout except it can only safely be used in depths of 6 metres (20 ft) or less because of the risk of oxygen toxicity.<sup id="cite_ref-DANnitrox_47-0" class="reference"><a href="#cite_note-DANnitrox-47"><span class="cite-bracket">[</span>47<span class="cite-bracket">]</span></a></sup></li> <li>An independent open-circuit system. The extra cylinders are heavy and cumbersome but larger cylinders let the diver carry more gas providing protection for the ascent from deeper and long dives. The <a href="/wiki/Breathing_gas" title="Breathing gas">breathing gas</a> mix must be carefully chosen to be safe at all depths of the ascent, or more than one set will be necessary. For long penetrations or decompression obligations, it may be necessary to carry multiple open-circuit bailout cylinders to provide enough gas. In such cases the chosen mixtures may be optimised to suit the worst case situation on the planned profile.<sup id="cite_ref-Pitkin_2023_44-2" class="reference"><a href="#cite_note-Pitkin_2023-44"><span class="cite-bracket">[</span>44<span class="cite-bracket">]</span></a></sup></li> <li>An independent bailout rebreather system.<sup id="cite_ref-Simanek_2021_19-11" class="reference"><a href="#cite_note-Simanek_2021-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Pitkin_2023_44-3" class="reference"><a href="#cite_note-Pitkin_2023-44"><span class="cite-bracket">[</span>44<span class="cite-bracket">]</span></a></sup></li> <li>A bailout rebreather system connected to the primary rebreather mouthpiece, selected by a bailout valve.<sup id="cite_ref-Pitkin_2023_44-4" class="reference"><a href="#cite_note-Pitkin_2023-44"><span class="cite-bracket">[</span>44<span class="cite-bracket">]</span></a></sup></li></ul> <p>The bailout system used on a specific dive will depend on the dive profile, diver qualification and preferences, code of practice where applicable, and availability of options. </p><p>In all cases when bailing out, the rebreather loop should be isolated from the ambient water to avoid flooding and loss of loop gas, which could adversely affect buoyancy. It may also be necessary to close the gas supply valves at the cylinders to prevent a malfunctioning control system or free-flowing ADV from continuing to add gas to the loop, which would also adversely affect buoyancy, possibly making it impracticable for the diver to remain at the correct depth for decompression. </p> <div class="mw-heading mw-heading4"><h4 id="Bailout_valve">Bailout valve</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=60" title="Edit section: Bailout valve"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:JJ_Rebreather_at_Blue_Rock_Quarry_PC290152.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/a/a2/JJ_Rebreather_at_Blue_Rock_Quarry_PC290152.jpg/220px-JJ_Rebreather_at_Blue_Rock_Quarry_PC290152.jpg" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/a/a2/JJ_Rebreather_at_Blue_Rock_Quarry_PC290152.jpg/330px-JJ_Rebreather_at_Blue_Rock_Quarry_PC290152.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/a/a2/JJ_Rebreather_at_Blue_Rock_Quarry_PC290152.jpg/440px-JJ_Rebreather_at_Blue_Rock_Quarry_PC290152.jpg 2x" data-file-width="4000" data-file-height="3000" /></a><figcaption>Bailout valve on JJ rebreather</figcaption></figure> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">See also: <a href="/wiki/Diving_rebreather#Bailout_valve" title="Diving rebreather">Diving rebreather § Bailout valve</a></div> <p>A bailout valve (BOV) is a switch-over valve fitted to the mouthpiece of a rebreather with a manually operated mechanism to switch from primary closed circuit to bailout, which may be an open or closed circuit breathing gas supply carried by the diver.<sup id="cite_ref-Pitkin_2023_44-5" class="reference"><a href="#cite_note-Pitkin_2023-44"><span class="cite-bracket">[</span>44<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading5"><h5 id="Open_circuit_bailout_valve">Open circuit bailout valve</h5><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=61" title="Edit section: Open circuit bailout valve"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The bailout valve (BOV) can switch to an open circuit demand valve fitted to the mouthpiece of a rebreather with a manually operated mechanism to switch from closed circuit to open circuit. The position selecting the open circuit demand valve may substitute for the closed state of a dive-surface valve (DSV) as the breathing loop is effectively sealed when on bailout.<sup id="cite_ref-Divesoft_48-0" class="reference"><a href="#cite_note-Divesoft-48"><span class="cite-bracket">[</span>48<span class="cite-bracket">]</span></a></sup> This type of bailout valve allows the diver to switch from closed circuit to open circuit without the need to change mouthpieces. This can save time in an emergency, as the bailout demand valve is in place for immediate use. This can be important in a situation of severe acute <a href="/wiki/Hypercapnia" title="Hypercapnia">hypercapnia</a>, when the diver physically cannot hold their breath long enough to change mouthpieces. Gas supply to the BOV is often from the on-board diluent cylinder, but arrangements can be made for off-board gas to be plumbed in using quick connectors.<sup id="cite_ref-ap_vision_5-27" class="reference"><a href="#cite_note-ap_vision-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading5"><h5 id="Closed_circuit_bailout_valve">Closed circuit bailout valve</h5><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=62" title="Edit section: Closed circuit bailout valve"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>A bailout valve can alternatively be provided that will switch to a closed circuit bailout system carried by the diver.<sup id="cite_ref-Pitkin_2023_44-6" class="reference"><a href="#cite_note-Pitkin_2023-44"><span class="cite-bracket">[</span>44<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading4"><h4 id="Bailout_to_open_circuit">Bailout to open circuit</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=63" title="Edit section: Bailout to open circuit"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">See also: <a href="/wiki/Diving_rebreather#Bailout_gas" title="Diving rebreather">Diving rebreather § Bailout gas</a></div> <p>Bailout to open circuit is generally considered a good option when there is any uncertainty as to what the problem is or whether it can be solved. The procedure for bailout depends on details of the rebreather construction and the bailout equipment chosen by the diver. Several methods may be possible: </p> <ul><li>Bailout to open circuit by switching the mouthpiece bailout valve to open circuit. This is easy to do and works well even when the diver is hypercapnic, as there is no need to hold the breath at all. This is a simple procedure and all that needs to be done in most cases is to rotate a valve handle on the mouthpiece assembly by 90°.</li> <li>Bailout to open circuit by opening a bailout demand valve already connected to the full face mask, or by nose-breathing in some cases. This also requires no removal of the mouthpiece. It requires a suitable model <a href="/wiki/Full-face_mask" class="mw-redirect" title="Full-face mask">full-face mask</a> with a secondary port for the demand valve. The procedure requires the supply valve on the open circuit demand valve to be opened, and generally the dive/surface valve of the rebreather to be closed.</li> <li>Bailout to open circuit by closing the DSV and exchanging the rebreather mouthpiece for a separate demand valve. This is simple, but requires the diver to hold their breath while switching the mouthpiece, which may not be possible in cases of hypercapnia.</li></ul> <p>Open circuit bailout is in common use, is relatively simple and straightforward to operate, and is mechanically reliable, but relatively complex to accurately estimate the amount of gas needed for a long and complex dive plan. The logistics of carrying sufficient open-circuit bailout gas for very long or deep dives can be a challenge. Available statistics suggest that very few fatalities are caused by inadequate bailout gas quantities.<sup id="cite_ref-Pitkin_2023_44-7" class="reference"><a href="#cite_note-Pitkin_2023-44"><span class="cite-bracket">[</span>44<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading5"><h5 id="Team_bailout">Team bailout</h5><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=64" title="Edit section: Team bailout"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The use of bailout gas distributed amongst team members can be used as a bailout strategy, but it generally only provides for rescue of one diver. Since the probability of a second diver also experiencing a rebreather failure on the same dive is low, this may be considered an acceptable risk by the team. This is a similar situation to recreational divers relying on the buddy for emergency gas in a situation where an immediate safe ascent to the surface is not possible. With this system the diver is never self-sufficient, and if a diver is separated from the group the emergency gas supply for the group is unavailable to all.<sup id="cite_ref-Simanek_46-1" class="reference"><a href="#cite_note-Simanek-46"><span class="cite-bracket">[</span>46<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading4"><h4 id="Bailout_to_rebreather">Bailout to rebreather</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=65" title="Edit section: Bailout to rebreather"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>An alternative to bailout to open circuit is bailout to rebreather, by closing the DSV of the primary rebreather's mouthpiece and switching to the mouthpiece of an independent bailout rebreather set. This is not bailing out to open circuit, but has logistical advantages in dives where the bulk of sufficient open circuit gas to reach the surface may be excessive, and a second rebreather is less bulky. There may be an intermediate stage where the diver bails out to open circuit on diluent gas while preparing the bailout rebreather.<sup id="cite_ref-Simanek_2021_19-12" class="reference"><a href="#cite_note-Simanek_2021-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Simanek_46-2" class="reference"><a href="#cite_note-Simanek-46"><span class="cite-bracket">[</span>46<span class="cite-bracket">]</span></a></sup> </p><p>To realise the full potential of closed circuit scuba for extended duration diving, an equivalent bailout system is necessary. Configurations using two back-mount rebreathers, a back-mount and a sidemount, and two sidemount rebreathers have been developed, tested, and found practicable for different situations. Proper and complete preparation and predive testing is essential, as it is not possible to correct some types of error in the water.<sup id="cite_ref-Simanek_46-3" class="reference"><a href="#cite_note-Simanek-46"><span class="cite-bracket">[</span>46<span class="cite-bracket">]</span></a></sup> </p><p>It is generally not safe to rely on an immediate switch to a bailout rebreather. It is necessary to check the loop before breathing from it, and there are bailout loop statuses that are extremely dangerous due to inappropriate internal pressure, or oxygen partial pressure. A preliminary bailout to open circuit gives the diver time to make a controlled assessment of the bailout loop status and make any adjustments necessary to make it safe to breathe at the current depth.<sup id="cite_ref-Simanek_46-4" class="reference"><a href="#cite_note-Simanek-46"><span class="cite-bracket">[</span>46<span class="cite-bracket">]</span></a></sup> </p><p>While the diver is not using the bailout rebreather they do not have feedback on the internal pressure of the loop, which may be lower or higher than ambient pressure, although the ADV and overpressure dump should automatically correct this if all the valves are set and working correctly, and nothing has been inadvertently or accidentally changed during the dive.<sup id="cite_ref-Simanek_46-5" class="reference"><a href="#cite_note-Simanek-46"><span class="cite-bracket">[</span>46<span class="cite-bracket">]</span></a></sup> It is prudent to check the bailout loop status during descent, occasionally during the bottom sector, and it is necessary to dump excess gas from its loop during ascent. It is critically important to avoid flooding either loop during these checks, by closing the mouthpiece before removing it from the mouth.<sup id="cite_ref-Simanek_46-6" class="reference"><a href="#cite_note-Simanek-46"><span class="cite-bracket">[</span>46<span class="cite-bracket">]</span></a></sup> </p><p>The bailout rebreather should, be placed so that the work of breathing is acceptable with the diver in the range of positions likely to be needed for the return to the surface. This requires the counterlungs to be at the depth of diver’s chest.<sup id="cite_ref-Simanek_46-7" class="reference"><a href="#cite_note-Simanek-46"><span class="cite-bracket">[</span>46<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading5"><h5 id="Bailout_software">Bailout software</h5><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=66" title="Edit section: Bailout software"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Some CCR electronic controllers are not compatible with being left running while the loop is not in use, and will try to achieve the set point regardless of whether it is practicable. A rebreather intended for this function can have a bailout setting, which puts the solenoids on standby, but monitors and displays the loop mixture. The effective and safe use of a bailout rebreather requires considerable practice, and presents the diver with a high level of task loading.<sup id="cite_ref-Simanek_46-8" class="reference"><a href="#cite_note-Simanek-46"><span class="cite-bracket">[</span>46<span class="cite-bracket">]</span></a></sup> </p> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1251242444"><table class="box-Expand_section plainlinks metadata ambox mbox-small-left ambox-content" role="presentation"><tbody><tr><td class="mbox-image"><span typeof="mw:File"><a href="/wiki/File:Wiki_letter_w_cropped.svg" class="mw-file-description"><img alt="[icon]" src="//upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Wiki_letter_w_cropped.svg/20px-Wiki_letter_w_cropped.svg.png" decoding="async" width="20" height="14" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Wiki_letter_w_cropped.svg/30px-Wiki_letter_w_cropped.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Wiki_letter_w_cropped.svg/40px-Wiki_letter_w_cropped.svg.png 2x" data-file-width="44" data-file-height="31" /></a></span></td><td class="mbox-text"><div class="mbox-text-span">This section <b>needs expansion</b> with: the need for software for bailout rebreahters to put them into standby mode until needed.. You can help by <a class="external text" href="https://en.wikipedia.org/w/index.php?title=Rebreather_diving&action=edit&section=">adding to it</a>. <span class="date-container"><i>(<span class="date">May 2024</span>)</i></span></div></td></tr></tbody></table> <div class="mw-heading mw-heading5"><h5 id="Bailout_rebreather_configurations">Bailout rebreather configurations</h5><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=67" title="Edit section: Bailout rebreather configurations"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Symmetrical: </p> <ul><li>Back mounted primary and bailout: Commonly similar or identical units mounted side-by-side on a common frame. This arrangement allows for simple attachment to a common mouthpiece with integral bailout valve.<sup id="cite_ref-Pitkin_2023_44-8" class="reference"><a href="#cite_note-Pitkin_2023-44"><span class="cite-bracket">[</span>44<span class="cite-bracket">]</span></a></sup></li> <li>Side mounted primary and bailout. Usually identical units, one carried on each side. Relatively simple, but not easy to combine with a bailout valve on a single mouthpiece.<sup id="cite_ref-Pitkin_2023_44-9" class="reference"><a href="#cite_note-Pitkin_2023-44"><span class="cite-bracket">[</span>44<span class="cite-bracket">]</span></a></sup></li></ul> <p>Asymmetrical: </p> <ul><li>Back mounted primary, side mounted bailout<sup id="cite_ref-Pitkin_2023_44-10" class="reference"><a href="#cite_note-Pitkin_2023-44"><span class="cite-bracket">[</span>44<span class="cite-bracket">]</span></a></sup></li> <li>Back mounted primary, chest mounted bailout<sup id="cite_ref-Pitkin_2023_44-11" class="reference"><a href="#cite_note-Pitkin_2023-44"><span class="cite-bracket">[</span>44<span class="cite-bracket">]</span></a></sup></li></ul> <div class="mw-heading mw-heading2"><h2 id="Training">Training</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=68" title="Edit section: Training"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">See also: <a href="/wiki/Diver_training" title="Diver training">Diver training</a></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:NAUI_Semi-closed_Rebreather_certification_card_PC160017.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/c/c0/NAUI_Semi-closed_Rebreather_certification_card_PC160017.jpg/220px-NAUI_Semi-closed_Rebreather_certification_card_PC160017.jpg" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/c/c0/NAUI_Semi-closed_Rebreather_certification_card_PC160017.jpg/330px-NAUI_Semi-closed_Rebreather_certification_card_PC160017.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/c/c0/NAUI_Semi-closed_Rebreather_certification_card_PC160017.jpg/440px-NAUI_Semi-closed_Rebreather_certification_card_PC160017.jpg 2x" data-file-width="4608" data-file-height="3456" /></a><figcaption>NAUI Semi-closed Rebreather certification card</figcaption></figure> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:US_Navy_090423-N-4301H-044_Basic_Underwater_Demolition_SEAL_(BUD-S)_candidates_check_their_underwater_breathing_apparatuses_for_proper_ventilation_and_safety_before_participating_in_dive_training_in_Coronado_Bay.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/c/c4/US_Navy_090423-N-4301H-044_Basic_Underwater_Demolition_SEAL_%28BUD-S%29_candidates_check_their_underwater_breathing_apparatuses_for_proper_ventilation_and_safety_before_participating_in_dive_training_in_Coronado_Bay.jpg/220px-thumbnail.jpg" decoding="async" width="220" height="146" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/c/c4/US_Navy_090423-N-4301H-044_Basic_Underwater_Demolition_SEAL_%28BUD-S%29_candidates_check_their_underwater_breathing_apparatuses_for_proper_ventilation_and_safety_before_participating_in_dive_training_in_Coronado_Bay.jpg/330px-thumbnail.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/c/c4/US_Navy_090423-N-4301H-044_Basic_Underwater_Demolition_SEAL_%28BUD-S%29_candidates_check_their_underwater_breathing_apparatuses_for_proper_ventilation_and_safety_before_participating_in_dive_training_in_Coronado_Bay.jpg/440px-thumbnail.jpg 2x" data-file-width="4288" data-file-height="2848" /></a><figcaption>Training includes pre-dive equipment tests</figcaption></figure> <p>Training in the use of rebreathers has two components: Generic training for the class of rebreather, including the theory of operation and the general procedures, and specific training for the model of rebreather, which covers the details of preparation, testing, user maintenance and troubleshooting, and those details of normal operating and emergency procedures which are specific to the model of rebreather. Crossover training from one model to another generally only requires the second aspect if the equipment is similar in design and operation.<sup id="cite_ref-Caney_et_al_2023_49-0" class="reference"><a href="#cite_note-Caney_et_al_2023-49"><span class="cite-bracket">[</span>49<span class="cite-bracket">]</span></a></sup> </p><p>Military organisations usually only use a small number of models. Typically an oxygen rebreather for attack swimmers, and a mixed gas rebreather for clearance diving work, and this simplifies the training and logistical requirements.<sup id="cite_ref-Ferris_and_Franberg_2023_50-0" class="reference"><a href="#cite_note-Ferris_and_Franberg_2023-50"><span class="cite-bracket">[</span>50<span class="cite-bracket">]</span></a></sup> </p><p>Rebreather diving for recreational purposes is generally classed as technical diving, and the training is provided by the technical diver certification agencies. Training of scientific divers on rebreathers is usually done by these same technical diver training agencies as the use of rebreathers by the scientific diving community is usually insufficient to justify separate in-house training.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (April 2013)">citation needed</span></a></i>]</sup> </p><p>Recreational and scientific diving applications draw on a far wider range of models, and any given technical diving training agency may issue certification for an arbitrary number of rebreathers depending on the skills of their registered instructors. Most recreational rebreather manufacturers require that training on their equipment is based on training originating from the manufacturer, i.e., the instructor trainers are typically certified by the manufacturer.<sup id="cite_ref-Caney_et_al_2023_49-1" class="reference"><a href="#cite_note-Caney_et_al_2023-49"><span class="cite-bracket">[</span>49<span class="cite-bracket">]</span></a></sup> </p><p>A consensus recommendation of the Rebreathers and Scientific Diving Workshop of February 2015 was that scientific rebreather divers should maintain currency in rebreather diving by a minimum annual activity of 12 dives with a minimum dive time of 12 hours, and that this might be insufficient for some activities. They also recommended that diver training should include management of an unresponsive rebreather diver.<sup id="cite_ref-Pollock_et_al_2016_51-0" class="reference"><a href="#cite_note-Pollock_et_al_2016-51"><span class="cite-bracket">[</span>51<span class="cite-bracket">]</span></a></sup> </p><p>As of 2023 there are several major new developments in equipment for which stable training has not yet been developed. Sidemount rebreathers are in a relatively advanced state compared to chest mount CCR, and particularly bailout rebreather procedures, which are still developing relatively fast, making it difficult to develop training standards.<sup id="cite_ref-Caney_et_al_2023_49-2" class="reference"><a href="#cite_note-Caney_et_al_2023-49"><span class="cite-bracket">[</span>49<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Scientific_diver_training">Scientific diver training</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=69" title="Edit section: Scientific diver training"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">See also: <a href="/wiki/Scientific_diving#Training_and_registration_of_scientific_divers" title="Scientific diving">Scientific diving § Training and registration of scientific divers</a></div> <p>As of 2016 there were three sets of rebreather standards for scientific diving in the US, those of the American Academy of Underwater Sciences (AAUS), National Park Service (NPS) and National Oceanic and Atmospheric Administration (NOAA).<sup id="cite_ref-Kintzing_and_Slattery_2016_52-0" class="reference"><a href="#cite_note-Kintzing_and_Slattery_2016-52"><span class="cite-bracket">[</span>52<span class="cite-bracket">]</span></a></sup> </p><p>All three organisations require full scientific diver status with nitrox certification as prerequisite, NOAA requires certification to 130 feet (40 m) and 100 open water dive, while AAUS and NPS require 100 feet (30 m) and 50 open water dives. Each agency specifies stepwise certification to increasing depths, and certification is valid only for the rebreather type trained on, for environmental conditions similar to those during training. Classroom training includes theory review of topics included in open circuit training, and decompression and dive planning appropriate to the chosen unit. More technical topics include system design and operation, pre-dive setup and testing, post-dive break down and maintenance, oxygen exposure and decompression management, dive operations planning, problem recognition and management specific to the chosen unit. Practical skills training includes system calibration and operation checks, preparation and management of absorbent canisters, breathing loop assembly, non-return valve function and pressure checks, gas analysis, pre-breathing function assessment, buoyancy control, system monitoring during the dive, bailout procedures, and system user maintenance, and experience exposure by way of minimum hours of underwater time under supervised conditions.<sup id="cite_ref-Kintzing_and_Slattery_2016_52-1" class="reference"><a href="#cite_note-Kintzing_and_Slattery_2016-52"><span class="cite-bracket">[</span>52<span class="cite-bracket">]</span></a></sup> </p><p>The wreck of a <a href="/wiki/Phoenicia" title="Phoenicia">Phoenician</a> ship off the coast of <a href="/wiki/Malta" title="Malta">Malta</a> at a depth of about 110 metres (360 ft) has been partially excavated by divers using <a href="/wiki/Diving_rebreather" title="Diving rebreather">rebreather equipment</a>, using techniques developed for the purpose to make the most effective use of time on site, which was restricted to 3 shifts of 12 minute each per day on site.<sup id="cite_ref-Gambin_2023_40-1" class="reference"><a href="#cite_note-Gambin_2023-40"><span class="cite-bracket">[</span>40<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Rebreather_Training_Council">Rebreather Training Council</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=70" title="Edit section: Rebreather Training Council"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The <a href="/wiki/Rebreather_Training_Council" class="mw-redirect" title="Rebreather Training Council">Rebreather Training Council</a> is an organisation with members from recreational/technical diver training agencies which train rebreather divers. Their function is to write training standards that ensure that there is reasonable consistency across the agencies so that divers get enough training to ensure an acceptable level of risk when diving within the guidelines of the training standard, and that there is mutual recognition of these standards between training agencies. They coordinate with the Rebreather Education and Safety Association (RESA) via the Combined Rebreather Industry Standards Alignment Group (CRISAG) so that the rebreather manufacturers and training agencies can both provide the necessary input to produce effective training standards. They also liaise directly with Working Group 1 – Diving Services of ISO Technical Committee 228 (Tourism and related services) to produce the training standards.<sup id="cite_ref-RTC_53-0" class="reference"><a href="#cite_note-RTC-53"><span class="cite-bracket">[</span>53<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-ISO_TC228_54-0" class="reference"><a href="#cite_note-ISO_TC228-54"><span class="cite-bracket">[</span>54<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Rebreather_Education_and_Safety_Association">Rebreather Education and Safety Association</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=71" title="Edit section: Rebreather Education and Safety Association"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The Rebreather Education and Safety Association (RESA) is a non-profit organisation mainly comprising rebreather manufacturers, but other organisations such as training agencies can be supporting members.<sup id="cite_ref-Caney_et_al_2023_49-3" class="reference"><a href="#cite_note-Caney_et_al_2023-49"><span class="cite-bracket">[</span>49<span class="cite-bracket">]</span></a></sup> </p><p>RESA was created to help improve safety and education in the rebreather industry. Regular (voting) members are manufacturers of rebreathers or significant subsystems.<sup id="cite_ref-RESA_55-0" class="reference"><a href="#cite_note-RESA-55"><span class="cite-bracket">[</span>55<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="ISO_training_standards">ISO training standards</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=72" title="Edit section: ISO training standards"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The ISO training standards are published by the International Organisation for Standards, and are minimum standards. A diver training agency can follow the standard as long as all the requirements are met, and can add as much additional course material as they see fit. Gas density limits are specified for training, with a preferred value of 5.2g/L and a maximum of 6.3g/L. These limits also effectively address narcotic limits. </p> <ul><li>ISO 24804 "Recreational Diving Services – Requirements for recreational rebreather diver training – No-decompression diving"<sup id="cite_ref-Caney_et_al_2023_49-4" class="reference"><a href="#cite_note-Caney_et_al_2023-49"><span class="cite-bracket">[</span>49<span class="cite-bracket">]</span></a></sup></li> <li>ISO 24805 "Recreational Diving Services – Requirements for recreational rebreather diver training – Decompression diving to 45m"<sup id="cite_ref-Caney_et_al_2023_49-5" class="reference"><a href="#cite_note-Caney_et_al_2023-49"><span class="cite-bracket">[</span>49<span class="cite-bracket">]</span></a></sup></li> <li>ISO 24806 "Recreational Diving Services – Requirements for recreational rebreather diver training – Decompression diving to 60m"<sup id="cite_ref-Caney_et_al_2023_49-6" class="reference"><a href="#cite_note-Caney_et_al_2023-49"><span class="cite-bracket">[</span>49<span class="cite-bracket">]</span></a></sup></li> <li>ISO 24807 "Recreational Diving Services – Requirements for recreational rebreather diver training – Decompression diving to 100m"<br />This does not limit divers to a maximum depth of 100m, but the training is not required to go below 100m.<sup id="cite_ref-Caney_et_al_2023_49-7" class="reference"><a href="#cite_note-Caney_et_al_2023-49"><span class="cite-bracket">[</span>49<span class="cite-bracket">]</span></a></sup></li> <li>ISO 24808 "Recreational Diving Services – Requirements for recreational rebreather instructor training"<br />There are four parts within this standard addressing the levels of instructor certification for training each of the diver levels.<sup id="cite_ref-Caney_et_al_2023_49-8" class="reference"><a href="#cite_note-Caney_et_al_2023-49"><span class="cite-bracket">[</span>49<span class="cite-bracket">]</span></a></sup></li></ul> <p><a href="/wiki/EUF_Certification_International" class="mw-redirect" title="EUF Certification International">EUF Certification International</a> is an independent body for global verification of rebreather training agencies based in Europe and associated with the Austrian Standards organisation. Agencies are certified for five years between renewals.<sup id="cite_ref-Caney_et_al_2023_49-9" class="reference"><a href="#cite_note-Caney_et_al_2023-49"><span class="cite-bracket">[</span>49<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-EUF_56-0" class="reference"><a href="#cite_note-EUF-56"><span class="cite-bracket">[</span>56<span class="cite-bracket">]</span></a></sup> </p><p>The adoption of the ISO standards will not have a very large impact on training course content, as most agencies already included most of the required content, but some agencies will have to adjust the number of dives and depths required for the specific courses.<sup id="cite_ref-InDepth_2023_57-0" class="reference"><a href="#cite_note-InDepth_2023-57"><span class="cite-bracket">[</span>57<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="History">History</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=73" title="Edit section: History"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">See also: <a href="/wiki/History_of_scuba_diving" title="History of scuba diving">History of scuba diving</a></div> <div class="mw-heading mw-heading3"><h3 id="Early_developments">Early developments</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=74" title="Edit section: Early developments"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The first commercially practical scuba rebreather was designed and built by the diving engineer <a href="/wiki/Henry_Fleuss" title="Henry Fleuss">Henry Fleuss</a> in 1878, while working for <a href="/wiki/Siebe_Gorman" title="Siebe Gorman">Siebe Gorman</a> in London.<sup id="cite_ref-davis1955_58-0" class="reference"><a href="#cite_note-davis1955-58"><span class="cite-bracket">[</span>58<span class="cite-bracket">]</span></a></sup> His <a href="/wiki/Self_contained_breathing_apparatus" class="mw-redirect" title="Self contained breathing apparatus">self contained breathing apparatus</a> consisted of a rubber mask connected to a breathing bag, with an estimated 50–60% oxygen supplied from a copper tank and carbon dioxide scrubbed by passing it through a bundle of rope yarn soaked in a solution of <a href="/wiki/Caustic_potash" class="mw-redirect" title="Caustic potash">caustic potash</a>, the system giving a dive duration of up to about three hours. Fleuss tested his device in 1879 by spending an hour submerged in a water tank, then one week later by diving to a depth of 5.5 metres (18 ft) in open water, on which occasion he was slightly injured when his assistants abruptly pulled him to the surface.<sup id="cite_ref-davis1955_58-1" class="reference"><a href="#cite_note-davis1955-58"><span class="cite-bracket">[</span>58<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Quick_1970_59-0" class="reference"><a href="#cite_note-Quick_1970-59"><span class="cite-bracket">[</span>59<span class="cite-bracket">]</span></a></sup> This apparatus was first used under operational conditions in 1880 by Alexander Lambert, the lead diver on the <a href="/wiki/Severn_Tunnel" title="Severn Tunnel">Severn Tunnel</a> construction project, who was able to travel 1,000 feet (300 m) in the darkness to close several submerged <a href="/wiki/Sluice" title="Sluice">sluice</a> doors in the tunnel; this had defeated the best efforts of <a href="/wiki/Standard_diving_dress" title="Standard diving dress">standard divers</a> due to extremely long distance, along which their air supply hoses became fouled on submerged debris, and the strong water currents in the workings.<sup id="cite_ref-davis1955_58-2" class="reference"><a href="#cite_note-davis1955-58"><span class="cite-bracket">[</span>58<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Bjorkman_60-0" class="reference"><a href="#cite_note-Bjorkman-60"><span class="cite-bracket">[</span>60<span class="cite-bracket">]</span></a></sup> </p><p>Fleuss continually improved his apparatus, adding a demand regulator<sup class="noprint Inline-Template" style="margin-left:0.1em; white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Please_clarify" title="Wikipedia:Please clarify"><span title="The text near this tag may need clarification or removal of jargon. (October 2021)">clarification needed</span></a></i>]</sup> and tanks capable of holding greater amounts of oxygen at higher pressure. Sir <a href="/wiki/Robert_Davis_(inventor)" title="Robert Davis (inventor)">Robert Davis</a>, head of Siebe Gorman, improved the oxygen rebreather in 1910<sup id="cite_ref-davis1955_58-3" class="reference"><a href="#cite_note-davis1955-58"><span class="cite-bracket">[</span>58<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Quick_1970_59-1" class="reference"><a href="#cite_note-Quick_1970-59"><span class="cite-bracket">[</span>59<span class="cite-bracket">]</span></a></sup> with his invention of the <a href="/wiki/Davis_Submerged_Escape_Apparatus" title="Davis Submerged Escape Apparatus">Davis Submerged Escape Apparatus</a>, the first rebreather to be made in quantity. While intended primarily as an emergency escape apparatus for <a href="/wiki/Submarine" title="Submarine">submarine</a> crews, it was soon also used for <a href="/wiki/Underwater_diving" title="Underwater diving">diving</a>, being a handy shallow water diving apparatus with a thirty-minute endurance, and as an <a href="/wiki/Self-contained_breathing_apparatus" title="Self-contained breathing apparatus">industrial breathing set</a>.<sup id="cite_ref-Quick_1970_59-2" class="reference"><a href="#cite_note-Quick_1970-59"><span class="cite-bracket">[</span>59<span class="cite-bracket">]</span></a></sup> </p> <figure class="mw-default-size mw-halign-left" typeof="mw:File/Thumb"><a href="/wiki/File:New_Davis_Breathing_Apparatus_Tested_at_the_Submarine_Escape_Test_Tank_at_HMS_Dolphin_Gosport,_14_December_1942_A13873.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/5/5e/New_Davis_Breathing_Apparatus_Tested_at_the_Submarine_Escape_Test_Tank_at_HMS_Dolphin_Gosport%2C_14_December_1942_A13873.jpg/220px-New_Davis_Breathing_Apparatus_Tested_at_the_Submarine_Escape_Test_Tank_at_HMS_Dolphin_Gosport%2C_14_December_1942_A13873.jpg" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/5/5e/New_Davis_Breathing_Apparatus_Tested_at_the_Submarine_Escape_Test_Tank_at_HMS_Dolphin_Gosport%2C_14_December_1942_A13873.jpg/330px-New_Davis_Breathing_Apparatus_Tested_at_the_Submarine_Escape_Test_Tank_at_HMS_Dolphin_Gosport%2C_14_December_1942_A13873.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/5/5e/New_Davis_Breathing_Apparatus_Tested_at_the_Submarine_Escape_Test_Tank_at_HMS_Dolphin_Gosport%2C_14_December_1942_A13873.jpg/440px-New_Davis_Breathing_Apparatus_Tested_at_the_Submarine_Escape_Test_Tank_at_HMS_Dolphin_Gosport%2C_14_December_1942_A13873.jpg 2x" data-file-width="2333" data-file-height="1748" /></a><figcaption><a href="/wiki/Davis_Submerged_Escape_Apparatus" title="Davis Submerged Escape Apparatus">Davis Submerged Escape Apparatus</a> being tested at the submarine escape test tank at <a href="/wiki/HMS_Dolphin_(shore_establishment)" title="HMS Dolphin (shore establishment)">HMS Dolphin, Gosport</a>, 14 December 1942.</figcaption></figure> <p>The rig comprised a rubber breathing/buoyancy bag containing a canister of <a href="/wiki/Barium_hydroxide" title="Barium hydroxide">barium hydroxide</a> to absorb exhaled carbon dioxide and, in a pocket at the lower end of the bag, a steel pressure cylinder holding approximately 56 litres (2.0 cu ft) of oxygen at a pressure of 120 bars (1,700 psi) which was equipped with a control valve and connected to the <a href="/wiki/Breathing_bag" class="mw-redirect" title="Breathing bag">breathing bag</a>. Opening the cylinder's valve admitted oxygen to the bag at ambient pressure. The rig also included an emergency buoyancy bag on its front to help keep the wearer afloat. After further development by Davis in 1927 the DSEA was adopted by the <a href="/wiki/Royal_Navy" title="Royal Navy">Royal Navy</a>.<sup id="cite_ref-Kemp_1990_61-0" class="reference"><a href="#cite_note-Kemp_1990-61"><span class="cite-bracket">[</span>61<span class="cite-bracket">]</span></a></sup> </p><p>In 1911 <a href="/wiki/Dr%C3%A4ger_(company)" title="Dräger (company)">Dräger</a> of Lübeck tested a self-contained semi-closed rebreather system for <a href="/wiki/Standard_diving_equipment" class="mw-redirect" title="Standard diving equipment">standard diving equipment</a>, which used an injector system to circulate the breathing gas through the scrubber and breathing loop, which included the full interior of the helmet. This was put into service soon thereafter and was available in two versions, an oxygen rebreather DM20 for depths shallower than 20 m, and a nitrox rebreather DM40 for depths up to 40 m. It was possible to minimise the work of breathing and use a helmet without a mouthpiece because the gas was pneumatically circulated.<sup id="cite_ref-Draegerwerk1899_62-0" class="reference"><a href="#cite_note-Draegerwerk1899-62"><span class="cite-bracket">[</span>62<span class="cite-bracket">]</span></a></sup> The US Navy developed a variant of the Mark V system for heliox diving. These were successfully used during the <a href="/wiki/USS_Sailfish_(SS-192)#Sinking_of_Squalus_and_recommissioning_as_Sailfish" title="USS Sailfish (SS-192)">rescue of the crew and salvage of the USS Squalus</a> in 1939. The US Navy Mark V Mod 1 heliox mixed gas helmet is based on the standard <a href="/wiki/Standard_diving_dress#US_Navy_Mk_V_equipment" title="Standard diving dress">Mark V Helmet</a>, with a scrubber canister mounted on the back of the helmet and an inlet gas injection system which recirculates the breathing gas through the scrubber to remove carbon dioxide and thereby conserve helium.<sup id="cite_ref-DESCO_29019_63-0" class="reference"><a href="#cite_note-DESCO_29019-63"><span class="cite-bracket">[</span>63<span class="cite-bracket">]</span></a></sup> The gas supply at the diver was controlled by two valves. The "Hoke valve" controlled flow through the injector to the "aspirator" which circulated gas from the helmet through the scrubber, and the main control valve used for bailout to open circuit, flushing the helmet, and for extra gas when working hard or descending. Flow rate of the injector nozzle was nominally 0.5 cubic foot per minute at 100 psi above ambient pressure, which would blow 11 times the volume of the injected gas through the scrubber.<sup id="cite_ref-USNDM_R1_64-0" class="reference"><a href="#cite_note-USNDM_R1-64"><span class="cite-bracket">[</span>64<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="World_War_II_era">World War II era</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=75" title="Edit section: World War II era"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>During the 1930s and all through <a href="/wiki/World_War_II" title="World War II">World War II</a>, the British, Italians and Germans developed and extensively used oxygen rebreathers to equip the first <a href="/wiki/Frogman" title="Frogman">frogmen</a>. The British adapted the Davis Submerged Escape Apparatus and the Germans adapted the Dräger submarine escape rebreathers, for their frogmen during the war.<sup id="cite_ref-Diving_Heritage_65-0" class="reference"><a href="#cite_note-Diving_Heritage-65"><span class="cite-bracket">[</span>65<span class="cite-bracket">]</span></a></sup> The Italians developed similar rebreathers for the combat swimmers of the <a href="/wiki/Decima_Flottiglia_MAS" title="Decima Flottiglia MAS">Decima Flottiglia MAS</a>, especially the <a href="/w/index.php?title=Pirelli_ARO&action=edit&redlink=1" class="new" title="Pirelli ARO (page does not exist)">Pirelli ARO</a>.<sup id="cite_ref-Pirelli_66-0" class="reference"><a href="#cite_note-Pirelli-66"><span class="cite-bracket">[</span>66<span class="cite-bracket">]</span></a></sup> In the U.S. Major <a href="/wiki/Christian_J._Lambertsen" title="Christian J. Lambertsen">Christian J. Lambertsen</a> invented an underwater free-swimming <a href="/wiki/Oxygen_rebreather" class="mw-redirect" title="Oxygen rebreather">oxygen rebreather</a> in 1939, which was accepted by the <a href="/wiki/Office_of_Strategic_Services" title="Office of Strategic Services">Office of Strategic Services</a>.<sup id="cite_ref-Shapiro_67-0" class="reference"><a href="#cite_note-Shapiro-67"><span class="cite-bracket">[</span>67<span class="cite-bracket">]</span></a></sup> In 1952 he patented a modification of his apparatus, this time named SCUBA,(an acronym for "self-contained underwater breathing apparatus"),<sup id="cite_ref-patent_68-0" class="reference"><a href="#cite_note-patent-68"><span class="cite-bracket">[</span>68<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Brubakk_2003_69-0" class="reference"><a href="#cite_note-Brubakk_2003-69"><span class="cite-bracket">[</span>69<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Vann_2004_70-0" class="reference"><a href="#cite_note-Vann_2004-70"><span class="cite-bracket">[</span>70<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Butler_2004_71-0" class="reference"><a href="#cite_note-Butler_2004-71"><span class="cite-bracket">[</span>71<span class="cite-bracket">]</span></a></sup> which later became the generic English word for autonomous breathing equipment for diving, and later for the activity using the equipment.<sup id="cite_ref-oxford_72-0" class="reference"><a href="#cite_note-oxford-72"><span class="cite-bracket">[</span>72<span class="cite-bracket">]</span></a></sup> After World War II, military frogmen continued to use rebreathers since they do not make bubbles which would give away the presence of the divers. The high percentage of oxygen used by these early rebreather systems limited the depth at which they could be used due to the risk of convulsions caused by acute <a href="/wiki/Oxygen_toxicity" title="Oxygen toxicity">oxygen toxicity</a>. </p> <div class="mw-heading mw-heading3"><h3 id="Technical_diving_era">Technical diving era</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=76" title="Edit section: Technical diving era"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>In the early days of technical diving (roughly the late 1980s and early 1990s) there was considerable interest in mixed gas rebreather technology, as it appeared to offer significantly extended bottom times, which in closed circuit systems, could be largely independent of depth. It also seemed useful for minimising decompression obligation and optimising decompression, though at the time the full complexity of achieving acceptably safe systems and procedures was not yet apparent, and the required technology was not yet readily available. The technical diving magazine <i><a href="/w/index.php?title=AquaCorps&action=edit&redlink=1" class="new" title="AquaCorps (page does not exist)">aquaCorps</a></i> first reported on rebreathers in their second issue in June 1990, and the topic was covered in most subsequent issues, including an entire issue in January 1993.<sup id="cite_ref-Menduno_2019_part3_73-0" class="reference"><a href="#cite_note-Menduno_2019_part3-73"><span class="cite-bracket">[</span>73<span class="cite-bracket">]</span></a></sup> </p><p>In May 1994 the first Rebreather Forum was held in Key West, Florida, organised by <a href="/w/index.php?title=Michael_Menduno&action=edit&redlink=1" class="new" title="Michael Menduno (page does not exist)">Michael Menduno</a> and <a href="/w/index.php?title=Tracy_Robinette&action=edit&redlink=1" class="new" title="Tracy Robinette (page does not exist)">Tracy Robinette</a>, with guests including Dr <a href="/wiki/Edward_D._Thalmann" title="Edward D. Thalmann">Edward D. Thalmann</a>, the US Navy diving physiology researcher, and developer of the US Navy's mixed-gas decompression tables, and inventor <a href="/w/index.php?title=Alan_Krasberg&action=edit&redlink=1" class="new" title="Alan Krasberg (page does not exist)">Alan Krasberg</a>, who had done significant development work on closed-circuit mixed-gas rebreathers. The 90 attendees included five rebreather manufacturers, several training agencies, and representatives from recreational, military, and commercial-diving communities. The forum recognised that there was a market for recreational rebreathers but no supply. The only community successfully using rebreathers at the time was the military, and their success depended on disciplined use and very good technical support. Commercial diving had rejected them as too complex and unreliable. It was also clear that training requirements for rebreather diving would be more complex than for open circuit, that semi-closed rebreathers would probably be easier to bring into the recreational diving market because of relative simplicity and lower cost, and that unlike the initial reaction to nitrox, there did not appear to be great concern that the technology was inappropriate for recreational diving – PADI technical development director <a href="/w/index.php?title=Karl_Shreeves&action=edit&redlink=1" class="new" title="Karl Shreeves (page does not exist)">Karl Shreeves</a> indicated that when the technology was ready PADI would provide training. Despite continued rebreather workshops and <a href="/wiki/Try-dive" class="mw-redirect" title="Try-dive">try-dives</a> at further annual conferences, actual rebreather availability was slow to materialise.<sup id="cite_ref-Menduno_2019_part3_73-1" class="reference"><a href="#cite_note-Menduno_2019_part3-73"><span class="cite-bracket">[</span>73<span class="cite-bracket">]</span></a></sup> </p><p>Dräger introduced a semi-closed circuit rebreather designed for recreational divers called the <i>Atlantis</i> in 1995. The company had accumulated experience in rebreather design and manufacturing going back to 1912, and was a major manufacturer of military rebreathers, which helped with credibility. In Japan, Grand Bleu marketed another recreational semi-closed unit called the <i>Fieno</i>.<sup id="cite_ref-Menduno_2019_part3_73-2" class="reference"><a href="#cite_note-Menduno_2019_part3-73"><span class="cite-bracket">[</span>73<span class="cite-bracket">]</span></a></sup> </p><p>Rebreather Forum 2.0 was held in Redondo Beach, California, in September 1996, and the proceedings were published by the PADI subsidiary <a href="/wiki/Diving_Science_and_Technology" title="Diving Science and Technology">Diving Science and Technology</a> (DSAT). At this time Dräger reported that it had sold about 850 Atlantis semi-closed rebreathers, and it was estimated that up to 3000 Fienos may have been sold in Japan. The British and US navies were at the time the largest users of mixed gas rebreathers, with an estimated 240 units in service. Somewhere in the order of 25 to 50 mixed gas units were estimated to be in use by the technical diving community, mostly by exploration teams and film-makers. The forum identified widespread interest in recreational rebreathers, and recognised that there were complex risks. At this stage there was no standardised training, and agencies were advised to work with manufacturers to develop effective responses to failure modes, and instructors were advised to own, or have access to, the models on which they were planning to provide training.<sup id="cite_ref-Menduno_2019_part3_73-3" class="reference"><a href="#cite_note-Menduno_2019_part3-73"><span class="cite-bracket">[</span>73<span class="cite-bracket">]</span></a></sup> </p><p>At this time only the US Navy 0.7atm constant PO<sub>2</sub> decompression tables had been validated for nitrox and heliox, and it was not clear whether reprogramming the existing algorithms to use the PO<sub>2</sub> provided by the rebreathers would be effective. Some recommendations published by the forum included third party testing for quality assurance, the use of full-face masks or mouthpiece retaining straps, adherence to the buddy system, and a maximum PO<sub>2</sub> setpoint of 1.3 atm. It was also recognised that the development and use of on-board CO<sub>2</sub> monitors, which were not available at the time, would contribute to improved safety.<sup id="cite_ref-Menduno_2019_part3_73-4" class="reference"><a href="#cite_note-Menduno_2019_part3-73"><span class="cite-bracket">[</span>73<span class="cite-bracket">]</span></a></sup> </p><p>In 1996 <a href="/w/index.php?title=Cis-Lunar_Development_Labs&action=edit&redlink=1" class="new" title="Cis-Lunar Development Labs (page does not exist)">Cis-Lunar Development Labs</a> was selling its MK-IV rebreather. About a year later (1997), <a href="/wiki/Ambient_Pressure_Diving" class="mw-redirect" title="Ambient Pressure Diving">Ambient Pressure Diving</a> in the UK started selling the <i>Inspiration</i> electronically controlled closed circuit rebreather, followed by the KISS from <a href="/wiki/Jetsam_Technologies" class="mw-redirect" title="Jetsam Technologies">Jetsam Technologies</a>.<sup id="cite_ref-Menduno_2019_part3_73-5" class="reference"><a href="#cite_note-Menduno_2019_part3-73"><span class="cite-bracket">[</span>73<span class="cite-bracket">]</span></a></sup> </p><p>By 1998 French cave diver <a href="/w/index.php?title=Olivier_Isler&action=edit&redlink=1" class="new" title="Olivier Isler (page does not exist)">Olivier Isler</a> used a fully redundant RI 2000 semi-closed rebreather in the <a href="/w/index.php?title=Doux_de_Coly&action=edit&redlink=1" class="new" title="Doux de Coly (page does not exist)">Doux de Coly</a> resurgence, France.<sup id="cite_ref-Menduno_2019_part3_73-6" class="reference"><a href="#cite_note-Menduno_2019_part3-73"><span class="cite-bracket">[</span>73<span class="cite-bracket">]</span></a></sup> </p><p>The recommendation for maximum PO<sub>2</sub> supported by the technical diving community has since risen to 1.4 atm for the working dive and 1.6 atm for decompression, partly due to advice from diving physiologist Dr <a href="/wiki/Robert_William_Hamilton_Jr." title="Robert William Hamilton Jr.">Bill Hamilton</a>, and partly due to satisfactory experience. Safety was predicted to be the biggest challenge to acceptance of rebreathers, and this proved to be true. There were 200 rebreather fatalities reported worldwide between 1998 and 2012, when the third rebreather forum was held: about 10 per year between 1998 and 2005, and about 20 per year from 2006 to 2012, which is a risk five to ten times greater than on open circuit scuba. Evidence suggests that safety has continued to improve since 2012.<sup id="cite_ref-Menduno_2019_part3_73-7" class="reference"><a href="#cite_note-Menduno_2019_part3-73"><span class="cite-bracket">[</span>73<span class="cite-bracket">]</span></a></sup> </p><p>Some dates: </p> <ul><li>1967 – Electrolung<sup id="cite_ref-Menduno_2023_74-0" class="reference"><a href="#cite_note-Menduno_2023-74"><span class="cite-bracket">[</span>74<span class="cite-bracket">]</span></a></sup></li> <li>1987 – <a href="/wiki/William_Stone_(caver)" title="William Stone (caver)">Bill Stone</a>'s FRED system<sup id="cite_ref-Menduno_2023_74-1" class="reference"><a href="#cite_note-Menduno_2023-74"><span class="cite-bracket">[</span>74<span class="cite-bracket">]</span></a></sup></li> <li>1994 – Rebreather Forum (1)<sup id="cite_ref-Menduno_2023_74-2" class="reference"><a href="#cite_note-Menduno_2023-74"><span class="cite-bracket">[</span>74<span class="cite-bracket">]</span></a></sup></li> <li><a href="/w/index.php?title=AquaCorps&action=edit&redlink=1" class="new" title="AquaCorps (page does not exist)">AquaCorps</a> journal started<sup id="cite_ref-Menduno_2023_74-3" class="reference"><a href="#cite_note-Menduno_2023-74"><span class="cite-bracket">[</span>74<span class="cite-bracket">]</span></a></sup></li> <li>Nitrox workshop<sup id="cite_ref-Menduno_2023_74-4" class="reference"><a href="#cite_note-Menduno_2023-74"><span class="cite-bracket">[</span>74<span class="cite-bracket">]</span></a></sup></li> <li>1993 – Tek Conference<sup id="cite_ref-Menduno_2023_74-5" class="reference"><a href="#cite_note-Menduno_2023-74"><span class="cite-bracket">[</span>74<span class="cite-bracket">]</span></a></sup></li> <li>1995 – Draeger Atlantis<sup id="cite_ref-Menduno_2023_74-6" class="reference"><a href="#cite_note-Menduno_2023-74"><span class="cite-bracket">[</span>74<span class="cite-bracket">]</span></a></sup></li> <li>1996 – Rebreather forum 2.0, 2 manufacturers of rebreathers available to the public: Atlantis and Fieno<sup id="cite_ref-Menduno_2023_74-7" class="reference"><a href="#cite_note-Menduno_2023-74"><span class="cite-bracket">[</span>74<span class="cite-bracket">]</span></a></sup></li> <li>1997 – AP Buddy Inspiration.<sup id="cite_ref-Menduno_2023_74-8" class="reference"><a href="#cite_note-Menduno_2023-74"><span class="cite-bracket">[</span>74<span class="cite-bracket">]</span></a></sup></li> <li>Cis Lunar Mk5, KISS Classic, Innerspace MEG, Halcyon RB80<sup id="cite_ref-Menduno_2023_74-9" class="reference"><a href="#cite_note-Menduno_2023-74"><span class="cite-bracket">[</span>74<span class="cite-bracket">]</span></a></sup></li> <li>2012 – Rebreather Forum 3, 12 manufacturers<sup id="cite_ref-Menduno_2023_74-10" class="reference"><a href="#cite_note-Menduno_2023-74"><span class="cite-bracket">[</span>74<span class="cite-bracket">]</span></a></sup></li> <li>2022 – 23 manufacturers, more than 40 models<sup id="cite_ref-Menduno_2023_74-11" class="reference"><a href="#cite_note-Menduno_2023-74"><span class="cite-bracket">[</span>74<span class="cite-bracket">]</span></a></sup></li> <li>2023 – Rebreather Forum 4<sup id="cite_ref-Menduno_2023_74-12" class="reference"><a href="#cite_note-Menduno_2023-74"><span class="cite-bracket">[</span>74<span class="cite-bracket">]</span></a></sup></li></ul> <div class="mw-heading mw-heading2"><h2 id="Applications">Applications</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=77" title="Edit section: Applications"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Rebreathers have applications in technical, recreational, scientific and military diving. In commercial diving some of the technology is used in conjunction with surface-supplied diving equipment, particularly as <a href="/wiki/Helium_reclaim_system" class="mw-redirect" title="Helium reclaim system">helium reclaim systems</a> and <a href="/wiki/Gas_extender" class="mw-redirect" title="Gas extender">gas extenders</a>, and for bailout equipment for closed bell diving. </p> <div class="mw-heading mw-heading3"><h3 id="Military_diving">Military diving</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=78" title="Edit section: Military diving"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">See also: <a href="/wiki/Military_diving" title="Military diving">Military diving</a>, <a href="/wiki/Frogman" title="Frogman">Frogman</a>, and <a href="/wiki/Clearance_diving" class="mw-redirect" title="Clearance diving">Clearance diving</a></div> <p><a href="/wiki/Tactical_diver" class="mw-redirect" title="Tactical diver">Tactical divers</a> (frogmen) are the main users of oxygen rebreathers, and for deeper work such as <a href="/wiki/Clearance_diving" class="mw-redirect" title="Clearance diving">clearance diving</a>, when mobility and a low magnetic and acoustic signature are important, mixed gas SCRs and CCRs may be used. Each military service that deploys rebreather divers usually standardises on a small number of models suited to their use, to simplify logistics and training.<sup id="cite_ref-Ferris_and_Franberg_2023_50-1" class="reference"><a href="#cite_note-Ferris_and_Franberg_2023-50"><span class="cite-bracket">[</span>50<span class="cite-bracket">]</span></a></sup> </p><p>The US Navy also uses rebreathers for saturation bailout sets (JFD Divex COBRA and JFD Divx MK IV Secondary Life Support (SCR))<sup id="cite_ref-Ferris_and_Franberg_2023_50-2" class="reference"><a href="#cite_note-Ferris_and_Franberg_2023-50"><span class="cite-bracket">[</span>50<span class="cite-bracket">]</span></a></sup> </p> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1251242444"><table class="box-Expand_section plainlinks metadata ambox mbox-small-left ambox-content" role="presentation"><tbody><tr><td class="mbox-image"><span typeof="mw:File"><a href="/wiki/File:Wiki_letter_w_cropped.svg" class="mw-file-description"><img alt="[icon]" src="//upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Wiki_letter_w_cropped.svg/20px-Wiki_letter_w_cropped.svg.png" decoding="async" width="20" height="14" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Wiki_letter_w_cropped.svg/30px-Wiki_letter_w_cropped.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Wiki_letter_w_cropped.svg/40px-Wiki_letter_w_cropped.svg.png 2x" data-file-width="44" data-file-height="31" /></a></span></td><td class="mbox-text"><div class="mbox-text-span">This section <b>needs expansion</b>. You can help by <a class="external text" href="https://en.wikipedia.org/w/index.php?title=Rebreather_diving&action=edit&section=">adding to it</a>. <span class="date-container"><i>(<span class="date">May 2024</span>)</i></span></div></td></tr></tbody></table> <div class="mw-heading mw-heading3"><h3 id="Technical_diving">Technical diving</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=79" title="Edit section: Technical diving"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Technical_diving" title="Technical diving">Technical diving</a></div> <p>The largest variety and number of mixed gas units have been used in the technical diving applications,<sup id="cite_ref-Menduno_2023_74-13" class="reference"><a href="#cite_note-Menduno_2023-74"><span class="cite-bracket">[</span>74<span class="cite-bracket">]</span></a></sup> </p><p>At the time of Rebreather Forum 3 (2011) there were three rec/tec rebreather training agencies active. By Rebreather Forum 4 (2023) there were eight: (BSAC, FFESSM, GUE, IANTD, PADI, RAID, SSI, and TDI). During this time the total certifications per year rose from 3545 in 2012 to 5156 in 2022. These numbers include multiple certifications for many divers, at different skill levels and for different rebreather classes and units. Mean age at certification was about 42 years with a peak in the 50 to 59 year age group, presumed to be related to availability of disposable income.<sup id="cite_ref-Caney_et_al_2023_49-10" class="reference"><a href="#cite_note-Caney_et_al_2023-49"><span class="cite-bracket">[</span>49<span class="cite-bracket">]</span></a></sup> </p> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1251242444"><table class="box-Expand_section plainlinks metadata ambox mbox-small-left ambox-content" role="presentation"><tbody><tr><td class="mbox-image"><span typeof="mw:File"><a href="/wiki/File:Wiki_letter_w_cropped.svg" class="mw-file-description"><img alt="[icon]" src="//upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Wiki_letter_w_cropped.svg/20px-Wiki_letter_w_cropped.svg.png" decoding="async" width="20" height="14" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Wiki_letter_w_cropped.svg/30px-Wiki_letter_w_cropped.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Wiki_letter_w_cropped.svg/40px-Wiki_letter_w_cropped.svg.png 2x" data-file-width="44" data-file-height="31" /></a></span></td><td class="mbox-text"><div class="mbox-text-span">This section <b>needs expansion</b>. You can help by <a class="external text" href="https://en.wikipedia.org/w/index.php?title=Rebreather_diving&action=edit&section=">adding to it</a>. <span class="date-container"><i>(<span class="date">May 2024</span>)</i></span></div></td></tr></tbody></table> <div class="mw-heading mw-heading3"><h3 id="Recreational_diving">Recreational diving</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=80" title="Edit section: Recreational diving"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Recreational_diving" title="Recreational diving">Recreational diving</a></div> <p>Rebreathers have not gained much traction in recreational diving, though a few models have been designed and marketed specifically for that purpose.<sup id="cite_ref-Menduno_2023_74-14" class="reference"><a href="#cite_note-Menduno_2023-74"><span class="cite-bracket">[</span>74<span class="cite-bracket">]</span></a></sup> </p> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1251242444"><table class="box-Expand_section plainlinks metadata ambox mbox-small-left ambox-content" role="presentation"><tbody><tr><td class="mbox-image"><span typeof="mw:File"><a href="/wiki/File:Wiki_letter_w_cropped.svg" class="mw-file-description"><img alt="[icon]" src="//upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Wiki_letter_w_cropped.svg/20px-Wiki_letter_w_cropped.svg.png" decoding="async" width="20" height="14" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Wiki_letter_w_cropped.svg/30px-Wiki_letter_w_cropped.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/1c/Wiki_letter_w_cropped.svg/40px-Wiki_letter_w_cropped.svg.png 2x" data-file-width="44" data-file-height="31" /></a></span></td><td class="mbox-text"><div class="mbox-text-span">This section <b>needs expansion</b>. You can help by <a class="external text" href="https://en.wikipedia.org/w/index.php?title=Rebreather_diving&action=edit&section=">adding to it</a>. <span class="date-container"><i>(<span class="date">May 2024</span>)</i></span></div></td></tr></tbody></table> <div class="mw-heading mw-heading3"><h3 id="Scientific_and_archaeological_diving">Scientific and archaeological diving</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=81" title="Edit section: Scientific and archaeological diving"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main articles: <a href="/wiki/Scientific_diving" title="Scientific diving">Scientific diving</a> and <a href="/wiki/Archaeological_diving" title="Archaeological diving">Archaeological diving</a></div> <p>Biological researchers have used closed-circuit rebreathers since the late 1960s, and wider application in marine science has grown since the turn of the century.<sup id="cite_ref-Pyle_et_al_2016_75-0" class="reference"><a href="#cite_note-Pyle_et_al_2016-75"><span class="cite-bracket">[</span>75<span class="cite-bracket">]</span></a></sup> </p><p>Between 1998 and 2013 some 52 organizational members of the AAUS reported 10,988 rebreather dives for a total duration of about 9,915 hours. There was one incidence each of decompression illness, idiopathic immersion pulmonary edema, and hypoxia associated with these dives.<sup id="cite_ref-Sellers_2016_76-0" class="reference"><a href="#cite_note-Sellers_2016-76"><span class="cite-bracket">[</span>76<span class="cite-bracket">]</span></a></sup> </p><p>During this period 1,675,350 open-circuit dives with a dive time of 1,148,783 hours were logged by AAUS members. The number of rebreather dives is about 0.7% of the total number and about 0.9% of the underwater time logged for OC dives, but the number and duration of rebreather dives has been growing fairly consistently over this period. 17 rebreather models were reported, including oxygen rebreathers and mixed gas rebreathers. 52% of the dives were for operational scientific purposes and 48% for training. 23% of the dives required decompression stops. During this period there has been a general increase in the number of deep dives of more than 191 feet (58 m) on rebreathers and a decrease in the number of deep dives on open circuit.<sup id="cite_ref-Sellers_2016_76-1" class="reference"><a href="#cite_note-Sellers_2016-76"><span class="cite-bracket">[</span>76<span class="cite-bracket">]</span></a></sup> </p><p>Rebreathers provide specific advantages for underwater biological research, particularly for applications that depend on unobtrusive observers or for a stealthy approach to wildlife for capture or tagging, and research that requires extended durations underwater, or operations in relatively deep (more than 50 metres (160 ft)) environments, especially in remote locations with logistic difficulties. Many scientific institutions have been slow to adopt rebreather technology, but developments in rebreather technology are expanding acceptance.<sup id="cite_ref-Pyle_et_al_2016_75-1" class="reference"><a href="#cite_note-Pyle_et_al_2016-75"><span class="cite-bracket">[</span>75<span class="cite-bracket">]</span></a></sup> </p><p>One of the early users of rebreathers for science was Walter Starck, who invented the first electronically-controlled closed-circuit rebreather for use in undersea biological research, which was soon followed by use in the <a href="/wiki/Tektite_habitat#Tektite_II" title="Tektite habitat">Tektite II</a> project for biological research during excursions from the submersed habitat. By the mid-1980s, interest in the application of rebreathers for scientific cave exploration coincided with amateur exploration activity which came to be known as technical diving, and underwater film-makers <a href="/w/index.php?title=Howard_Hall_(filmmaker)&action=edit&redlink=1" class="new" title="Howard Hall (filmmaker) (page does not exist)">Howard Hall</a> and <a href="/w/index.php?title=Bob_Cranston&action=edit&redlink=1" class="new" title="Bob Cranston (page does not exist)">Bob Cranston</a> started to use rebreathers to approach marine life underwater with less risk of affecting behaviour.<sup id="cite_ref-Pyle_et_al_2016_75-2" class="reference"><a href="#cite_note-Pyle_et_al_2016-75"><span class="cite-bracket">[</span>75<span class="cite-bracket">]</span></a></sup> </p><p>In the middle- to late-1990s, rebreathers became more easily available from several manufacturers, and the scientific community started to use them more often, particularly where their logistical advantages were most apparent.<sup id="cite_ref-Pyle_et_al_2016_75-3" class="reference"><a href="#cite_note-Pyle_et_al_2016-75"><span class="cite-bracket">[</span>75<span class="cite-bracket">]</span></a></sup> </p><p>A major advantage of closed-circuit rebreathers for biological research diving is the absence of noise and visual disturbance due to the bubbles of exhaled gas, which is known to have disruptive effects on animal behaviour. This has proved particularly effective where the diver needs to closely approach or capture animals like sea otters, and has considerably facilitated recording of animal sounds. Use of rebreathers reduces problems of multiple dives and decompressions by allowing divers to conduct a single, long-duration dive without the need to return to the surface or shore between multiple dives, particularly where continuous observation is desirable. The ability to maintain a constant oxygen partial pressure can allow very much longer dive times in the middle depth ranges without incurring a decompression obligation, and can allow a single multilevel dive to suffice where several open circuit dives were previously required. The capital outlay for equipment and training can sometimes be rapidly offset by the improved efficiency of getting a job done in one dive on one day. Considerable savings on the cost of helium diluent are possible for deeper dives specially in remote locations where the cost of helium may be ten times that in industrialised areas.<sup id="cite_ref-Pyle_et_al_2016_75-4" class="reference"><a href="#cite_note-Pyle_et_al_2016-75"><span class="cite-bracket">[</span>75<span class="cite-bracket">]</span></a></sup> </p><p>Research submersibles allow direct access to deeper environments, but cost much more than rebreathers to operate and are limited to regions where such submersibles are in active use because of the logistical requirements and cost of running the support vessels. They are also limited in their ability to explore, sample, and document complex coral reef structures due to bulk and maneuverability and dexterity limitations.<sup id="cite_ref-Pyle_et_al_2016_75-5" class="reference"><a href="#cite_note-Pyle_et_al_2016-75"><span class="cite-bracket">[</span>75<span class="cite-bracket">]</span></a></sup> </p><p>Developments in electronically controlled closed circuit mixed gas rebreathers have extended the range of ambient pressure scientific diving since the mid 1990s. Various research stakeholders have started to seek and acquire data from locations which were previously inaccessible. Scientific diving programs have been establishing and developing technical diving facilities to allow marine scientists to safely access these regions. The nature of this extended range diving exposure makes it necessary to modify and adapt procedures to ensure acceptably safe operations. To a large degree this implies a high level of competence in operating the rebreather equipment, so the diver has sufficient excess capacity to allow the scientific task to be carried out successfully without compromising safety. This requires a high level of competence as a condition for completing initial training and maintenance of this competence by sufficient appropriate diving activity, or by refresher training and work-up dives following a period of inactivity. The use of institutionally approved checklists for equipment preparation and dive planning has been recommended as a way to reduce error and ensure that all essential steps are followed.<sup id="cite_ref-Kesling_2016_77-0" class="reference"><a href="#cite_note-Kesling_2016-77"><span class="cite-bracket">[</span>77<span class="cite-bracket">]</span></a></sup> </p><p>In scientific diving the primary objective is normally the planned task of the dive, and the dive is the most effective way to get to and from the place where the scientific work is to be done. In the underwater environment life-support must necessarily take priority over all other considerations, and when neglected may have fatal results. Open circuit equipment is simple robust and reliable and requires little management beyond gas and decompression status monitoring. With rebreathers the gas mixture is dynamic and monitoring and where necessary, control of the equipment is of critical importance. Procedural modifications may be needed to retain a similar level of safety.<sup id="cite_ref-Short_2016_78-0" class="reference"><a href="#cite_note-Short_2016-78"><span class="cite-bracket">[</span>78<span class="cite-bracket">]</span></a></sup> </p><p>The considerable variation in control systems between makes and in some cases models, of electronically controlled rebreathers makes it unrealistic to expect to be able to maintain reflexive familiarity with several units, and also have sufficient capacity to perform the scientific task effectively on top of managing the rebreather, and the more complex the dive and the more complex the scientific work the greater the risk. Besides ensuring adequate pre-dive testing to ensure that the equipment is functioning correctly, having a team member less invested in the science and highly skilled with the rebreather available to monitor the working diver or a pair of working divers and their equipment has been put forward as a way to reduce the risk of a failure going unnoticed or ignored. This safety support diver can also reduce task loading of the researcher by carrying some of the scientific equipment.<sup id="cite_ref-Short_2016_78-1" class="reference"><a href="#cite_note-Short_2016-78"><span class="cite-bracket">[</span>78<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Mixed_mode_and_mixed_platform_diving">Mixed mode and mixed platform diving</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=82" title="Edit section: Mixed mode and mixed platform diving"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>A mixed mode dive team is a buddy team where the divers use different modes of diving on the same dive, such as one diver on open circuit and the other on rebreather. Mixed platform rebreather diving refers to the use of different makes or models of rebreather on the same dive.<sup id="cite_ref-Seymour_2016_79-0" class="reference"><a href="#cite_note-Seymour_2016-79"><span class="cite-bracket">[</span>79<span class="cite-bracket">]</span></a></sup> </p><p>There are dive profiles and tasks in which mixed modes may not work well because of incompatible requirements for bottom times, decompression and gas planning, but there is a wide range of operations where this is much less of a problem, however it is necessary for both members of the team to be able to assist each other in an emergency, which requires the ability to recognise problems, and the knowledge, skills and equipment to respond appropriately. This includes knowledge of emergency procedures appropriate to the other diver's equipment. Some training and briefing is necessary, and appropriate procedures should be covered in the operations manual. Similar considerations apply to mixed platform diving, but to a lesser extent.<sup id="cite_ref-Seymour_2016_79-1" class="reference"><a href="#cite_note-Seymour_2016-79"><span class="cite-bracket">[</span>79<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=83" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Diving_safety" title="Diving safety">Diving safety</a> – Risk management of underwater diving activities</li> <li><a href="/wiki/Diving_rebreather" title="Diving rebreather">Diving rebreather</a> – Closed or semi-closed circuit scuba</li> <li><a href="/wiki/Rebreather" title="Rebreather">Rebreather</a> – Portable apparatus to recycle breathing gas</li> <li><a href="/wiki/Scuba_diving" title="Scuba diving">Scuba diving</a> – Swimming underwater, breathing gas carried by the diver</li></ul> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=84" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist"> <div class="mw-references-wrap mw-references-columns"><ol class="references"> <li id="cite_note-apdiving-1"><span class="mw-cite-backlink">^ <a href="#cite_ref-apdiving_1-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-apdiving_1-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-apdiving_1-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-apdiving_1-3"><sup><i><b>d</b></i></sup></a> <a href="#cite_ref-apdiving_1-4"><sup><i><b>e</b></i></sup></a> <a href="#cite_ref-apdiving_1-5"><sup><i><b>f</b></i></sup></a> <a href="#cite_ref-apdiving_1-6"><sup><i><b>g</b></i></sup></a> <a href="#cite_ref-apdiving_1-7"><sup><i><b>h</b></i></sup></a> <a href="#cite_ref-apdiving_1-8"><sup><i><b>i</b></i></sup></a> <a href="#cite_ref-apdiving_1-9"><sup><i><b>j</b></i></sup></a> <a href="#cite_ref-apdiving_1-10"><sup><i><b>k</b></i></sup></a> <a href="#cite_ref-apdiving_1-11"><sup><i><b>l</b></i></sup></a> <a href="#cite_ref-apdiving_1-12"><sup><i><b>m</b></i></sup></a> <a href="#cite_ref-apdiving_1-13"><sup><i><b>n</b></i></sup></a> <a href="#cite_ref-apdiving_1-14"><sup><i><b>o</b></i></sup></a> <a href="#cite_ref-apdiving_1-15"><sup><i><b>p</b></i></sup></a></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.apdiving.com/en/rebreathers/new-to-ccr/">"Rebreathers guide for beginners"</a>. <i>apdiving.com</i>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20240605073639/https://www.apdiving.com/en/rebreathers/new-to-ccr/">Archived</a> from the original on 5 June 2024<span class="reference-accessdate">. Retrieved <span class="nowrap">11 May</span> 2021</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=apdiving.com&rft.atitle=Rebreathers+guide+for+beginners&rft_id=https%3A%2F%2Fwww.apdiving.com%2Fen%2Frebreathers%2Fnew-to-ccr%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Rhea_2021-2"><span class="mw-cite-backlink">^ <a href="#cite_ref-Rhea_2021_2-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Rhea_2021_2-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFRhea2021" class="citation web cs1">Rhea, David (2 February 2021). <a rel="nofollow" class="external text" href="https://gue.com/blog/halcyons-rb80-semi-closed-rebreather-a-specialized-exploration-tool/">"The RB80 Semi-closed Rebreather: A Successful Exploration Tool"</a>. <i>gue.com</i>. In Depth. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20210225104416/https://gue.com/blog/halcyons-rb80-semi-closed-rebreather-a-specialized-exploration-tool/">Archived</a> from the original on 25 February 2021<span class="reference-accessdate">. Retrieved <span class="nowrap">16 February</span> 2021</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=gue.com&rft.atitle=The+RB80+Semi-closed+Rebreather%3A+A+Successful+Exploration+Tool&rft.date=2021-02-02&rft.aulast=Rhea&rft.aufirst=David&rft_id=https%3A%2F%2Fgue.com%2Fblog%2Fhalcyons-rb80-semi-closed-rebreather-a-specialized-exploration-tool%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-rebreather2.0-3"><span class="mw-cite-backlink">^ <a href="#cite_ref-rebreather2.0_3-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-rebreather2.0_3-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFRichardsonMendunoShreeves1996" class="citation journal cs1">Richardson D, Menduno M, Shreeves K (1996). "Proceedings of Rebreather Forum 2.0". <i>Diving Science and Technology Workshop.</i>: 286.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Diving+Science+and+Technology+Workshop.&rft.atitle=Proceedings+of+Rebreather+Forum+2.0.&rft.pages=286&rft.date=1996&rft.aulast=Richardson&rft.aufirst=D&rft.au=Menduno%2C+M&rft.au=Shreeves%2C+K&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Goble-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-Goble_4-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFGoble2003" class="citation journal cs1">Goble, Steve (2003). "Rebreathers". <i><a href="/wiki/South_Pacific_Underwater_Medicine_Society" title="South Pacific Underwater Medicine Society">South Pacific Underwater Medicine Society</a></i>. <b>33</b> (2): 98–102.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=South+Pacific+Underwater+Medicine+Society&rft.atitle=Rebreathers&rft.volume=33&rft.issue=2&rft.pages=98-102&rft.date=2003&rft.aulast=Goble&rft.aufirst=Steve&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-ap_vision-5"><span class="mw-cite-backlink">^ <a href="#cite_ref-ap_vision_5-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-ap_vision_5-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-ap_vision_5-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-ap_vision_5-3"><sup><i><b>d</b></i></sup></a> <a href="#cite_ref-ap_vision_5-4"><sup><i><b>e</b></i></sup></a> <a href="#cite_ref-ap_vision_5-5"><sup><i><b>f</b></i></sup></a> <a href="#cite_ref-ap_vision_5-6"><sup><i><b>g</b></i></sup></a> <a href="#cite_ref-ap_vision_5-7"><sup><i><b>h</b></i></sup></a> <a href="#cite_ref-ap_vision_5-8"><sup><i><b>i</b></i></sup></a> <a href="#cite_ref-ap_vision_5-9"><sup><i><b>j</b></i></sup></a> <a href="#cite_ref-ap_vision_5-10"><sup><i><b>k</b></i></sup></a> <a href="#cite_ref-ap_vision_5-11"><sup><i><b>l</b></i></sup></a> <a href="#cite_ref-ap_vision_5-12"><sup><i><b>m</b></i></sup></a> <a href="#cite_ref-ap_vision_5-13"><sup><i><b>n</b></i></sup></a> <a href="#cite_ref-ap_vision_5-14"><sup><i><b>o</b></i></sup></a> <a href="#cite_ref-ap_vision_5-15"><sup><i><b>p</b></i></sup></a> <a href="#cite_ref-ap_vision_5-16"><sup><i><b>q</b></i></sup></a> <a href="#cite_ref-ap_vision_5-17"><sup><i><b>r</b></i></sup></a> <a href="#cite_ref-ap_vision_5-18"><sup><i><b>s</b></i></sup></a> <a href="#cite_ref-ap_vision_5-19"><sup><i><b>t</b></i></sup></a> <a href="#cite_ref-ap_vision_5-20"><sup><i><b>u</b></i></sup></a> <a href="#cite_ref-ap_vision_5-21"><sup><i><b>v</b></i></sup></a> <a href="#cite_ref-ap_vision_5-22"><sup><i><b>w</b></i></sup></a> <a href="#cite_ref-ap_vision_5-23"><sup><i><b>x</b></i></sup></a> <a href="#cite_ref-ap_vision_5-24"><sup><i><b>y</b></i></sup></a> <a href="#cite_ref-ap_vision_5-25"><sup><i><b>z</b></i></sup></a> <a href="#cite_ref-ap_vision_5-26"><sup><i><b>aa</b></i></sup></a> <a href="#cite_ref-ap_vision_5-27"><sup><i><b>ab</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFParker2012" class="citation web cs1">Parker, Martin (November 2012). <a rel="nofollow" class="external text" href="https://www.apdiving.com/en/wp-content/uploads/Rebreather_Vision_-Instruction-Manual-Nov12.pdf">"Rebreather user manual"</a> <span class="cs1-format">(PDF)</span>. <i>apdiving.com</i>. Ambient Pressure Diving Ltd. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20210512150311/https://www.apdiving.com/en/wp-content/uploads/Rebreather_Vision_-Instruction-Manual-Nov12.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 12 May 2021<span class="reference-accessdate">. Retrieved <span class="nowrap">11 May</span> 2021</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=apdiving.com&rft.atitle=Rebreather+user+manual&rft.date=2012-11&rft.aulast=Parker&rft.aufirst=Martin&rft_id=https%3A%2F%2Fwww.apdiving.com%2Fen%2Fwp-content%2Fuploads%2FRebreather_Vision_-Instruction-Manual-Nov12.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-popmech-dec06-58-6"><span class="mw-cite-backlink">^ <a href="#cite_ref-popmech-dec06-58_6-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-popmech-dec06-58_6-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-popmech-dec06-58_6-2"><sup><i><b>c</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFReynolds2006" class="citation journal cs1">Reynolds, Glen Harlan (December 2006). "Seeking New Depths". <i>Popular Mechanics</i>. <b>183</b> (12): 58.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Popular+Mechanics&rft.atitle=Seeking+New+Depths&rft.volume=183&rft.issue=12&rft.pages=58&rft.date=2006-12&rft.aulast=Reynolds&rft.aufirst=Glen+Harlan&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Lobel2005-7"><span class="mw-cite-backlink"><b><a href="#cite_ref-Lobel2005_7-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFLobel2005" class="citation journal cs1">Lobel, Phillip S. (2005). "Scuba Bubble Noise and Fish Behavior: A Rationale for Silent Diving Technology". <i>In: Godfrey, JM; Shumway, SE. Diving for Science 2005. Proceedings of the American Academy of Underwater Sciences Symposium on March 10–12, 2005 at the University of Connecticut at Avery Point, Groton, Connecticut</i>. <a href="/wiki/American_Academy_of_Underwater_Sciences" title="American Academy of Underwater Sciences">American Academy of Underwater Sciences</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=In%3A+Godfrey%2C+JM%3B+Shumway%2C+SE.+Diving+for+Science+2005.+Proceedings+of+the+American+Academy+of+Underwater+Sciences+Symposium+on+March+10%E2%80%9312%2C+2005+at+the+University+of+Connecticut+at+Avery+Point%2C+Groton%2C+Connecticut.&rft.atitle=Scuba+Bubble+Noise+and+Fish+Behavior%3A+A+Rationale+for+Silent+Diving+Technology&rft.date=2005&rft.aulast=Lobel&rft.aufirst=Phillip+S.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Josan-Drinceanu_et_al-8"><span class="mw-cite-backlink">^ <a href="#cite_ref-Josan-Drinceanu_et_al_8-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Josan-Drinceanu_et_al_8-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-Josan-Drinceanu_et_al_8-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-Josan-Drinceanu_et_al_8-3"><sup><i><b>d</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFJosan-Drinceanude_WeckFilburn2015" class="citation conference cs1">Josan-Drinceanu, Ioana; de Weck, Olivier L.; Filburn, Thomas (12–16 July 2015). <a rel="nofollow" class="external text" href="https://ttu-ir.tdl.org/bitstream/handle/2346/64465/ICES_2015_submission_192.pdf?sequence=1"><i>Analytical model and simulations of closed-loop rebreather systems for Earth and Space applications</i></a> <span class="cs1-format">(PDF)</span>. 45th International Conference on Environmental Systems. Bellevue, Washington, US. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20210515021656/https://ttu-ir.tdl.org/bitstream/handle/2346/64465/ICES_2015_submission_192.pdf?sequence=1">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 15 May 2021<span class="reference-accessdate">. Retrieved <span class="nowrap">14 May</span> 2021</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=conference&rft.btitle=Analytical+model+and+simulations+of+closed-loop+rebreather+systems+for+Earth+and+Space+applications&rft.place=Bellevue%2C+Washington%2C+US&rft.date=2015-07-12%2F2015-07-16&rft.aulast=Josan-Drinceanu&rft.aufirst=Ioana&rft.au=de+Weck%2C+Olivier+L.&rft.au=Filburn%2C+Thomas&rft_id=https%3A%2F%2Fttu-ir.tdl.org%2Fbitstream%2Fhandle%2F2346%2F64465%2FICES_2015_submission_192.pdf%3Fsequence%3D1&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Manning_2002-9"><span class="mw-cite-backlink"><b><a href="#cite_ref-Manning_2002_9-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFManning2002" class="citation journal cs1">Manning, A.M. (2002). "Oxygen therapy and toxicity". <i>Veterinary Clinics of North America: Small Animal Practice</i>. <b>32</b> (5): 1005–1020. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1016%2FS0195-5616%2802%2900043-8">10.1016/S0195-5616(02)00043-8</a>. <a href="/wiki/PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/12380161">12380161</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Veterinary+Clinics+of+North+America%3A+Small+Animal+Practice&rft.atitle=Oxygen+therapy+and+toxicity.&rft.volume=32&rft.issue=5&rft.pages=1005-1020&rft.date=2002&rft_id=info%3Adoi%2F10.1016%2FS0195-5616%2802%2900043-8&rft_id=info%3Apmid%2F12380161&rft.aulast=Manning&rft.aufirst=A.M.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Partridge2010-10"><span class="mw-cite-backlink"><b><a href="#cite_ref-Partridge2010_10-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFPartridge2010" class="citation web cs1">Partridge, Mathew (2010). <a rel="nofollow" class="external text" href="https://web.archive.org/web/20180322024722if_/http://www.tech-ccr.com/pdf/study-lounge-ccr/Rebreather%20Failures.pdf">"CCR Common Failures Chart – Rebreather Basics"</a> <span class="cs1-format">(PDF)</span>. tech-ccr.com. Archived from <a rel="nofollow" class="external text" href="http://www.tech-ccr.com/pdf/study-lounge-ccr/Rebreather%20Failures.pdf">the original</a> <span class="cs1-format">(PDF)</span> on 22 March 2018<span class="reference-accessdate">. Retrieved <span class="nowrap">23 February</span> 2015</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=CCR+Common+Failures+Chart+%E2%80%93+Rebreather+Basics&rft.pub=tech-ccr.com&rft.date=2010&rft.aulast=Partridge&rft.aufirst=Mathew&rft_id=http%3A%2F%2Fwww.tech-ccr.com%2Fpdf%2Fstudy-lounge-ccr%2FRebreather%2520Failures.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-DIRrbBailout-11"><span class="mw-cite-backlink"><b><a href="#cite_ref-DIRrbBailout_11-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFVerdierLee2008" class="citation report cs1">Verdier, C.; Lee, D. A. (2008). Motor skills learning and current bailout procedures in recreational rebreather diving. <i>Nitrox Rebreather Diving</i> (Report). DIRrebreather publishing.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=report&rft.btitle=Motor+skills+learning+and+current+bailout+procedures+in+recreational+rebreather+diving&rft.pub=DIRrebreather+publishing&rft.date=2008&rft.aulast=Verdier&rft.aufirst=C.&rft.au=Lee%2C+D.+A.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-alpinist-12"><span class="mw-cite-backlink"><b><a href="#cite_ref-alpinist_12-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFLiddiard" class="citation web cs1">Liddiard, John. <a rel="nofollow" class="external text" href="http://www.jlunderwater.co.uk/old_site/photoix/bailout/bailout.htm">"Bailout"</a>. jlunderwater.co.uk. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20090808153621/http://www.jlunderwater.co.uk/old_site/photoix/bailout/bailout.htm">Archived</a> from the original on 8 August 2009<span class="reference-accessdate">. Retrieved <span class="nowrap">3 March</span> 2009</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Bailout&rft.pub=jlunderwater.co.uk&rft.aulast=Liddiard&rft.aufirst=John&rft_id=http%3A%2F%2Fwww.jlunderwater.co.uk%2Fold_site%2Fphotoix%2Fbailout%2Fbailout.htm&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Morrison-13"><span class="mw-cite-backlink"><b><a href="#cite_ref-Morrison_13-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMorrisonReimers1982" class="citation book cs1">Morrison, J.B; Reimers, S.D. (1982). <i>Bennett and Elliott's Physiology and Medicine of Diving</i> (3rd ed.). Best Publishing Company. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/0941332020" title="Special:BookSources/0941332020"><bdi>0941332020</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Bennett+and+Elliott%27s+Physiology+and+Medicine+of+Diving&rft.edition=3rd&rft.pub=Best+Publishing+Company&rft.date=1982&rft.isbn=0941332020&rft.aulast=Morrison&rft.aufirst=J.B&rft.au=Reimers%2C+S.D.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-CMF-14"><span class="mw-cite-backlink">^ <a href="#cite_ref-CMF_14-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-CMF_14-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFLarsson2004" class="citation web cs1">Larsson, Åke (30 September 2004). <a rel="nofollow" class="external text" href="http://www.teknosofen.com/cmf_scr_tech.htm">"Åkes' Constant Massflow Rebreather Technical Page"</a>. Teknosofen.com. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20131209192658/http://teknosofen.com/cmf_scr_tech.htm">Archived</a> from the original on 9 December 2013<span class="reference-accessdate">. Retrieved <span class="nowrap">31 July</span> 2013</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=%C3%85kes%27+Constant+Massflow+Rebreather+Technical+Page&rft.pub=Teknosofen.com&rft.date=2004-09-30&rft.aulast=Larsson&rft.aufirst=%C3%85ke&rft_id=http%3A%2F%2Fwww.teknosofen.com%2Fcmf_scr_tech.htm&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Nuckols-15"><span class="mw-cite-backlink">^ <a href="#cite_ref-Nuckols_15-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Nuckols_15-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFNuckolsClarkeMarr1999" class="citation journal cs1">Nuckols, M.L.; Clarke, J.R.; Marr, W.J. (1999). "Assessment of oxygen levels in alternative designs of semiclosed underwater breathing apparatus". <i>Life Support & Biosphere Science: International Journal of Earth Space</i>. <b>6</b> (3): 239–249. <a href="/wiki/PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/11542685">11542685</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Life+Support+%26+Biosphere+Science%3A+International+Journal+of+Earth+Space&rft.atitle=Assessment+of+oxygen+levels+in+alternative+designs+of+semiclosed+underwater+breathing+apparatus&rft.volume=6&rft.issue=3&rft.pages=239-249&rft.date=1999&rft_id=info%3Apmid%2F11542685&rft.aulast=Nuckols&rft.aufirst=M.L.&rft.au=Clarke%2C+J.R.&rft.au=Marr%2C+W.J.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-DC55-16"><span class="mw-cite-backlink">^ <a href="#cite_ref-DC55_16-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-DC55_16-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFLarsson2002" class="citation web cs1">Larsson, Åke (15 July 2002). <a rel="nofollow" class="external text" href="http://www.teknosofen.com/dc55_tech.htm">"Le Spirotechnique DC55"</a>. Teknosofen.com. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20131209192107/http://teknosofen.com/dc55_tech.htm">Archived</a> from the original on 9 December 2013<span class="reference-accessdate">. Retrieved <span class="nowrap">31 July</span> 2013</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Le+Spirotechnique+DC55&rft.pub=Teknosofen.com&rft.date=2002-07-15&rft.aulast=Larsson&rft.aufirst=%C3%85ke&rft_id=http%3A%2F%2Fwww.teknosofen.com%2Fdc55_tech.htm&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-pmid21384764-17"><span class="mw-cite-backlink"><b><a href="#cite_ref-pmid21384764_17-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFFrånbergEricssonLarssonLindholm2011" class="citation journal cs1">Frånberg, O; Ericsson, M; Larsson, A; Lindholm, P. (2011). "Investigation of a demand-controlled rebreather in connection with a diving accident". <i><a href="/wiki/Undersea_%26_Hyperbaric_Medicine" class="mw-redirect" title="Undersea & Hyperbaric Medicine">Undersea & Hyperbaric Medicine</a></i>. <b>38</b> (1): 61–72. <a href="/wiki/PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/21384764">21384764</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Undersea+%26+Hyperbaric+Medicine&rft.atitle=Investigation+of+a+demand-controlled+rebreather+in+connection+with+a+diving+accident&rft.volume=38&rft.issue=1&rft.pages=61-72&rft.date=2011&rft_id=info%3Apmid%2F21384764&rft.aulast=Fr%C3%A5nberg&rft.aufirst=O&rft.au=Ericsson%2C+M&rft.au=Larsson%2C+A&rft.au=Lindholm%2C+P.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Fock_2012-18"><span class="mw-cite-backlink"><b><a href="#cite_ref-Fock_2012_18-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFFock2012" class="citation conference cs1">Fock, Andrew W. (18–20 May 2012). Vann, Richard D.; Denoble, Petar J.; Pollock, Neal W. (eds.). <a rel="nofollow" class="external text" href="https://web.archive.org/web/20140717033807/http://media.dan.org/RF3_web.pdf"><i>Analysis of recreational closed-circuit rebreather deaths 1998–2010</i></a> <span class="cs1-format">(PDF)</span>. Rebreather Forum 3 Proceedings. Durham, North Carolina: AAUS/DAN/PADI. pp. 119–127. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-9800423-9-9" title="Special:BookSources/978-0-9800423-9-9"><bdi>978-0-9800423-9-9</bdi></a>. Archived from <a rel="nofollow" class="external text" href="http://media.dan.org/RF3_web.pdf">the original</a> <span class="cs1-format">(PDF)</span> on 17 July 2014<span class="reference-accessdate">. Retrieved <span class="nowrap">26 December</span> 2017</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=conference&rft.btitle=Analysis+of+recreational+closed-circuit+rebreather+deaths+1998%E2%80%932010&rft.place=Durham%2C+North+Carolina&rft.pages=119-127&rft.pub=AAUS%2FDAN%2FPADI&rft.date=2012-05-18%2F2012-05-20&rft.isbn=978-0-9800423-9-9&rft.aulast=Fock&rft.aufirst=Andrew+W.&rft_id=http%3A%2F%2Fmedia.dan.org%2FRF3_web.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Simanek_2021-19"><span class="mw-cite-backlink">^ <a href="#cite_ref-Simanek_2021_19-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Simanek_2021_19-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-Simanek_2021_19-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-Simanek_2021_19-3"><sup><i><b>d</b></i></sup></a> <a href="#cite_ref-Simanek_2021_19-4"><sup><i><b>e</b></i></sup></a> <a href="#cite_ref-Simanek_2021_19-5"><sup><i><b>f</b></i></sup></a> <a href="#cite_ref-Simanek_2021_19-6"><sup><i><b>g</b></i></sup></a> <a href="#cite_ref-Simanek_2021_19-7"><sup><i><b>h</b></i></sup></a> <a href="#cite_ref-Simanek_2021_19-8"><sup><i><b>i</b></i></sup></a> <a href="#cite_ref-Simanek_2021_19-9"><sup><i><b>j</b></i></sup></a> <a href="#cite_ref-Simanek_2021_19-10"><sup><i><b>k</b></i></sup></a> <a href="#cite_ref-Simanek_2021_19-11"><sup><i><b>l</b></i></sup></a> <a href="#cite_ref-Simanek_2021_19-12"><sup><i><b>m</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFŠimánek2021" class="citation web cs1">Šimánek, Jakub (2 February 2021). <a rel="nofollow" class="external text" href="https://gue.com/blog/building-a-fault-tolerant-rebreather-our-path-to-simplicity/">"Building A Fault Tolerant Rebreather: Our Path to Simplicity"</a>. <i>In Depth</i>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20210207130757/https://gue.com/blog/building-a-fault-tolerant-rebreather-our-path-to-simplicity/">Archived</a> from the original on 7 February 2021<span class="reference-accessdate">. Retrieved <span class="nowrap">12 February</span> 2021</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=In+Depth&rft.atitle=Building+A+Fault+Tolerant+Rebreather%3A+Our+Path+to+Simplicity&rft.date=2021-02-02&rft.aulast=%C5%A0im%C3%A1nek&rft.aufirst=Jakub&rft_id=https%3A%2F%2Fgue.com%2Fblog%2Fbuilding-a-fault-tolerant-rebreather-our-path-to-simplicity%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Menduno_2012-20"><span class="mw-cite-backlink"><b><a href="#cite_ref-Menduno_2012_20-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMenduno2012" class="citation conference cs1">Menduno, Michael (18–20 May 2012). Vann, Richard D.; Denoble, Petar J.; Pollock, Neal W. (eds.). <a rel="nofollow" class="external text" href="https://web.archive.org/web/20140717033807/http://media.dan.org/RF3_web.pdf"><i>Building a consumer rebreather market: Lessons from the technical diving revolution</i></a> <span class="cs1-format">(PDF)</span>. Rebreather Forum 3 Proceedings. Durham, North Carolina: AAUS/DAN/PADI. pp. 2–23. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-9800423-9-9" title="Special:BookSources/978-0-9800423-9-9"><bdi>978-0-9800423-9-9</bdi></a>. Archived from <a rel="nofollow" class="external text" href="http://media.dan.org/RF3_web.pdf">the original</a> <span class="cs1-format">(PDF)</span> on 17 July 2014<span class="reference-accessdate">. Retrieved <span class="nowrap">26 December</span> 2017</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=conference&rft.btitle=Building+a+consumer+rebreather+market%3A+Lessons+from+the+technical+diving+revolution&rft.place=Durham%2C+North+Carolina&rft.pages=2-23&rft.pub=AAUS%2FDAN%2FPADI&rft.date=2012-05-18%2F2012-05-20&rft.isbn=978-0-9800423-9-9&rft.aulast=Menduno&rft.aufirst=Michael&rft_id=http%3A%2F%2Fmedia.dan.org%2FRF3_web.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-XRay-mag_Pridmore-21"><span class="mw-cite-backlink"><b><a href="#cite_ref-XRay-mag_Pridmore_21-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFPridmore2012" class="citation web cs1">Pridmore, Simon (22 April 2012). <a rel="nofollow" class="external text" href="http://www.xray-mag.com/content/insidious-threat-hypoxic-blackout-rebreather-diving">"The Insidious Threat of Hypoxic Blackout in Rebreather Diving"</a>. <i>X-Ray Mag</i>. AquaScope Media ApS. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20180322020537/http://www.xray-mag.com/content/insidious-threat-hypoxic-blackout-rebreather-diving">Archived</a> from the original on 22 March 2018<span class="reference-accessdate">. Retrieved <span class="nowrap">21 March</span> 2018</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=X-Ray+Mag&rft.atitle=The+Insidious+Threat+of+Hypoxic+Blackout+in+Rebreather+Diving&rft.date=2012-04-22&rft.aulast=Pridmore&rft.aufirst=Simon&rft_id=http%3A%2F%2Fwww.xray-mag.com%2Fcontent%2Finsidious-threat-hypoxic-blackout-rebreather-diving&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-ClarkeScrubber2013-22"><span class="mw-cite-backlink">^ <a href="#cite_ref-ClarkeScrubber2013_22-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-ClarkeScrubber2013_22-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFClarke2013" class="citation web cs1"><a href="/wiki/John_R._Clarke_(scientist)" title="John R. Clarke (scientist)">Clarke, John R.</a> (11 November 2013). <a rel="nofollow" class="external text" href="http://johnclarkeonline.com/2013/11/11/how-does-your-rebreather-scrubber-handle-the-deep/">"How Does Your Rebreather Scrubber Handle the Deep?"</a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20150224045547/http://johnclarkeonline.com/2013/11/11/how-does-your-rebreather-scrubber-handle-the-deep/">Archived</a> from the original on 24 February 2015<span class="reference-accessdate">. Retrieved <span class="nowrap">23 February</span> 2015</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=How+Does+Your+Rebreather+Scrubber+Handle+the+Deep%3F&rft.date=2013-11-11&rft.aulast=Clarke&rft.aufirst=John+R.&rft_id=http%3A%2F%2Fjohnclarkeonline.com%2F2013%2F11%2F11%2Fhow-does-your-rebreather-scrubber-handle-the-deep%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Mesley_2023-23"><span class="mw-cite-backlink">^ <a href="#cite_ref-Mesley_2023_23-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Mesley_2023_23-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-Mesley_2023_23-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-Mesley_2023_23-3"><sup><i><b>d</b></i></sup></a> <a href="#cite_ref-Mesley_2023_23-4"><sup><i><b>e</b></i></sup></a> <a href="#cite_ref-Mesley_2023_23-5"><sup><i><b>f</b></i></sup></a> <a href="#cite_ref-Mesley_2023_23-6"><sup><i><b>g</b></i></sup></a> <a href="#cite_ref-Mesley_2023_23-7"><sup><i><b>h</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMesley2023" class="citation web cs1">Mesley, Pete (20–22 April 2023). <a rel="nofollow" class="external text" href="https://gue.tv/programs/rebreather-diving-education-ccr-training-standards">"Equipment options for diver safety"</a>. <i>Rebreather Forum 4</i>. Valetta, Malta. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20240501180643/https://gue.tv/programs/rebreather-diving-education-ccr-training-standards">Archived</a> from the original on 1 May 2024<span class="reference-accessdate">. Retrieved <span class="nowrap">5 June</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=Rebreather+Forum+4&rft.atitle=Equipment+options+for+diver+safety&rft.date=2023-04-20%2F2023-04-22&rft.aulast=Mesley&rft.aufirst=Pete&rft_id=https%3A%2F%2Fgue.tv%2Fprograms%2Frebreather-diving-education-ccr-training-standards&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-MSAchemox-24"><span class="mw-cite-backlink">^ <a href="#cite_ref-MSAchemox_24-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-MSAchemox_24-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFBech2003" class="citation web cs1">Bech, J-W. (20 June 2003). <a rel="nofollow" class="external text" href="http://www.therebreathersite.nl/Zuurstofrebreathers/USA/msa_chemox.htm">"MSA Chemox SCBA"</a>. therebreathersite.nl. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20150928130732/http://www.therebreathersite.nl/Zuurstofrebreathers/USA/msa_chemox.htm">Archived</a> from the original on 28 September 2015<span class="reference-accessdate">. Retrieved <span class="nowrap">23 February</span> 2015</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=MSA+Chemox+SCBA&rft.pub=therebreathersite.nl&rft.date=2003-06-20&rft.aulast=Bech&rft.aufirst=J-W.&rft_id=http%3A%2F%2Fwww.therebreathersite.nl%2FZuurstofrebreathers%2FUSA%2Fmsa_chemox.htm&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Lang_2001-25"><span class="mw-cite-backlink"><b><a href="#cite_ref-Lang_2001_25-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFLang2001" class="citation book cs1">Lang, Michael A., ed. (2001). <i>DAN nitrox workshop proceedings</i>. Durham, NC: Divers Alert Network, 197 pages.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=DAN+nitrox+workshop+proceedings&rft.place=Durham%2C+NC&rft.pub=Divers+Alert+Network%2C+197+pages&rft.date=2001&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Mitchell_2008-26"><span class="mw-cite-backlink">^ <a href="#cite_ref-Mitchell_2008_26-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Mitchell_2008_26-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMitchell2008" class="citation book cs1">Mitchell, Simon J. (August 2008). "4: Carbon dioxide retention". In Mount, Tom; Dituri, Joseph (eds.). <i>Exploration and Mixed Gas Diving Encyclopedia</i> (1st ed.). Miami Shores, Florida: International Association of Nitrox Divers. pp. 51–60. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-915539-10-9" title="Special:BookSources/978-0-915539-10-9"><bdi>978-0-915539-10-9</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=bookitem&rft.atitle=4%3A+Carbon+dioxide+retention&rft.btitle=Exploration+and+Mixed+Gas+Diving+Encyclopedia&rft.place=Miami+Shores%2C+Florida&rft.pages=51-60&rft.edition=1st&rft.pub=International+Association+of+Nitrox+Divers&rft.date=2008-08&rft.isbn=978-0-915539-10-9&rft.aulast=Mitchell&rft.aufirst=Simon+J.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Lillo_et_al_1996-27"><span class="mw-cite-backlink"><b><a href="#cite_ref-Lillo_et_al_1996_27-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFLilloRubyGumminPorter1996" class="citation journal cs1">Lillo, R.S.; Ruby, A.; Gummin, D.D.; Porter, W.R.; Caldwell, J.M. (March 1996). "Chemical safety of U.S. Navy Fleet soda lime". <i>Undersea and Hyperbaric Medicine Journal</i>. <b>23</b> (1): 43–53. <a href="/wiki/PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/8653065">8653065</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Undersea+and+Hyperbaric+Medicine+Journal&rft.atitle=Chemical+safety+of+U.S.+Navy+Fleet+soda+lime&rft.volume=23&rft.issue=1&rft.pages=43-53&rft.date=1996-03&rft_id=info%3Apmid%2F8653065&rft.aulast=Lillo&rft.aufirst=R.S.&rft.au=Ruby%2C+A.&rft.au=Gummin%2C+D.D.&rft.au=Porter%2C+W.R.&rft.au=Caldwell%2C+J.M.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Warkander_2007-28"><span class="mw-cite-backlink"><b><a href="#cite_ref-Warkander_2007_28-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFWarkander2007" class="citation journal cs1">Warkander, Dan E. (2007). "Development of a scrubber gauge for closed-circuit diving". <i>Undersea and Hyperbaric Medicine Abstract</i>. <b>34</b>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Undersea+and+Hyperbaric+Medicine+Abstract&rft.atitle=Development+of+a+scrubber+gauge+for+closed-circuit+diving&rft.volume=34&rft.date=2007&rft.aulast=Warkander&rft.aufirst=Dan+E.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-AP_Diving_scrubber_monitor-29"><span class="mw-cite-backlink"><b><a href="#cite_ref-AP_Diving_scrubber_monitor_29-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.apdiving.com/shop/evolution-tempstick.html">"Vision electronics: Scrubber life monitor"</a>. <i>apdiving</i>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20180322015524/https://www.apdiving.com/shop/evolution-tempstick.html">Archived</a> from the original on 22 March 2018<span class="reference-accessdate">. Retrieved <span class="nowrap">3 July</span> 2013</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=apdiving&rft.atitle=Vision+electronics%3A+Scrubber+life+monitor&rft_id=https%3A%2F%2Fwww.apdiving.com%2Fshop%2Fevolution-tempstick.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-30"><span class="mw-cite-backlink"><b><a href="#cite_ref-30">^</a></b></span> <span class="reference-text">Cells from the same batch with the same history are more likely to fail together in the same way than cells with a different history</span> </li> <li id="cite_note-Jones_2012-31"><span class="mw-cite-backlink">^ <a href="#cite_ref-Jones_2012_31-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Jones_2012_31-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-Jones_2012_31-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-Jones_2012_31-3"><sup><i><b>d</b></i></sup></a> <a href="#cite_ref-Jones_2012_31-4"><sup><i><b>e</b></i></sup></a> <a href="#cite_ref-Jones_2012_31-5"><sup><i><b>f</b></i></sup></a> <a href="#cite_ref-Jones_2012_31-6"><sup><i><b>g</b></i></sup></a> <a href="#cite_ref-Jones_2012_31-7"><sup><i><b>h</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFJones2012" class="citation conference cs1">Jones, Nigel A. (18–20 May 2012). Vann, Richard D.; Denoble, Petar J.; Pollock, Neal W. (eds.). <a rel="nofollow" class="external text" href="https://web.archive.org/web/20140717033807/http://media.dan.org/RF3_web.pdf"><i>PO2 sensor redundancy</i></a> <span class="cs1-format">(PDF)</span>. Rebreather Forum 3 Proceedings. Durham, North Carolina: AAUS/DAN/PADI. pp. 193–292. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-9800423-9-9" title="Special:BookSources/978-0-9800423-9-9"><bdi>978-0-9800423-9-9</bdi></a>. Archived from <a rel="nofollow" class="external text" href="http://media.dan.org/RF3_web.pdf">the original</a> <span class="cs1-format">(PDF)</span> on 17 July 2014<span class="reference-accessdate">. Retrieved <span class="nowrap">26 December</span> 2017</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=conference&rft.btitle=PO2+sensor+redundancy&rft.place=Durham%2C+North+Carolina&rft.pages=193-292&rft.pub=AAUS%2FDAN%2FPADI&rft.date=2012-05-18%2F2012-05-20&rft.isbn=978-0-9800423-9-9&rft.aulast=Jones&rft.aufirst=Nigel+A.&rft_id=http%3A%2F%2Fmedia.dan.org%2FRF3_web.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Deas_and_Davidov_2006-32"><span class="mw-cite-backlink"><b><a href="#cite_ref-Deas_and_Davidov_2006_32-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFDeasDavidov2006" class="citation report cs1">Deas, Alex; Davidov, Bob (2006). <a rel="nofollow" class="external text" href="http://www.deeplife.co.uk/or_files/Effect_of_flooding_with_granules_061027.pdf">Verification report: Effect of flooding on breathing resistance of granual [<i>sic</i>] scrubber. Revision A</a> <span class="cs1-format">(PDF)</span> (Report). Deep Life Ltd. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20120901015538/http://www.deeplife.co.uk/or_files/Effect_of_flooding_with_granules_061027.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 1 September 2012<span class="reference-accessdate">. Retrieved <span class="nowrap">25 April</span> 2013</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=report&rft.btitle=Verification+report%3A+Effect+of+flooding+on+breathing+resistance+of+granual%26%2332%3B%26%2391%3Bsic%26%2393%3B+scrubber.+Revision+A&rft.pub=Deep+Life+Ltd.&rft.date=2006&rft.aulast=Deas&rft.aufirst=Alex&rft.au=Davidov%2C+Bob&rft_id=http%3A%2F%2Fwww.deeplife.co.uk%2For_files%2FEffect_of_flooding_with_granules_061027.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-AAUS-2007-33"><span class="mw-cite-backlink">^ <a href="#cite_ref-AAUS-2007_33-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-AAUS-2007_33-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFVannPollockDenoble2007" class="citation journal cs1 cs1-prop-long-vol">Vann, R.D.; Pollock, N.W.; Denoble, P.J. (2007). "Rebreather Fatality Investigation". <i>In: NW Pollock and JM Godfrey (Eds.) the Diving for Science…2007</i>. Proceedings of the American Academy of Underwater Sciences (Twenty-sixth annual Scientific Diving Symposium). Dauphin Island, Ala.: American Academy of Underwater Sciences. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-9800423-1-3" title="Special:BookSources/978-0-9800423-1-3"><bdi>978-0-9800423-1-3</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=In%3A+NW+Pollock+and+JM+Godfrey+%28Eds.%29+the+Diving+for+Science%E2%80%A62007&rft.atitle=Rebreather+Fatality+Investigation&rft.volume=Proceedings+of+the+American+Academy+of+Underwater+Sciences&rft.issue=Twenty-sixth+annual+Scientific+Diving+Symposium&rft.date=2007&rft.isbn=978-0-9800423-1-3&rft.aulast=Vann&rft.aufirst=R.D.&rft.au=Pollock%2C+N.W.&rft.au=Denoble%2C+P.J.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-HRKP-34"><span class="mw-cite-backlink">^ <a href="#cite_ref-HRKP_34-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-HRKP_34-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.deeplife.co.uk/files/How_Rebreathers_Kill_People.pdf">"How rebreathers kill people"</a> <span class="cs1-format">(PDF)</span>. Deep Life Ltd. 2010. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20120901015527/http://www.deeplife.co.uk/files/How_Rebreathers_Kill_People.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 1 September 2012<span class="reference-accessdate">. Retrieved <span class="nowrap">25 April</span> 2013</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=How+rebreathers+kill+people&rft.pub=Deep+Life+Ltd.&rft.date=2010&rft_id=http%3A%2F%2Fwww.deeplife.co.uk%2Ffiles%2FHow_Rebreathers_Kill_People.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Fock_2013-35"><span class="mw-cite-backlink">^ <a href="#cite_ref-Fock_2013_35-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Fock_2013_35-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-Fock_2013_35-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-Fock_2013_35-3"><sup><i><b>d</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFFock2013" class="citation journal cs1">Fock, Andrew W. (June 2013). <a rel="nofollow" class="external text" href="http://www.dhmjournal.com/files/Fock-Rebreather_deaths.pdf">"Analysis of recreational closed-circuit rebreather deaths 1998–2010"</a> <span class="cs1-format">(PDF)</span>. <i>Diving and Hyperbaric Medicine</i>. <b>43</b> (2): 78–85. <a href="/wiki/PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/23813461">23813461</a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20130627030900/http://www.dhmjournal.com/files/Fock-Rebreather_deaths.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 27 June 2013<span class="reference-accessdate">. Retrieved <span class="nowrap">17 June</span> 2013</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Diving+and+Hyperbaric+Medicine&rft.atitle=Analysis+of+recreational+closed-circuit+rebreather+deaths+1998%E2%80%932010&rft.volume=43&rft.issue=2&rft.pages=78-85&rft.date=2013-06&rft_id=info%3Apmid%2F23813461&rft.aulast=Fock&rft.aufirst=Andrew+W.&rft_id=http%3A%2F%2Fwww.dhmjournal.com%2Ffiles%2FFock-Rebreather_deaths.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Stone1986-36"><span class="mw-cite-backlink"><b><a href="#cite_ref-Stone1986_36-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFStone,_William_C.1986" class="citation journal cs1"><a href="/wiki/William_Stone_(caver)" title="William Stone (caver)">Stone, William C.</a> (1986). "Design of fully redundant autonomous life support systems". <i>In: Mitchell, CT (Eds.) Diving for Science 86. Proceedings of the American Academy of Underwater Sciences Sixth Annual Scientific Diving Symposium. Held October 31 – November 3, 1986 in Tallahassee, Florida, USA</i>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=In%3A+Mitchell%2C+CT+%28Eds.%29+Diving+for+Science+86.+Proceedings+of+the+American+Academy+of+Underwater+Sciences+Sixth+Annual+Scientific+Diving+Symposium.+Held+October+31+%E2%80%93+November+3%2C+1986+in+Tallahassee%2C+Florida%2C+USA.&rft.atitle=Design+of+fully+redundant+autonomous+life+support+systems&rft.date=1986&rft.au=Stone%2C+William+C.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-RTC_MRS-37"><span class="mw-cite-backlink">^ <a href="#cite_ref-RTC_MRS_37-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-RTC_MRS_37-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFHaynesMendunoToomer2023" class="citation web cs1">Haynes, P; Menduno, M; Toomer, P (21 March 2023). <a rel="nofollow" class="external text" href="https://rebreathertrainingcouncil.org/wp-content/uploads/2021/03/RTC-MRS-Guidance-Issue-1-2021-03-23.pdf">"Rebreather Training Council. Mouthpiece Retraining Strap Safety Guidance Notice, Issue"</a> <span class="cs1-format">(PDF)</span>. <i>rebreathertrainingcouncil.org</i><span class="reference-accessdate">. Retrieved <span class="nowrap">3 April</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=rebreathertrainingcouncil.org&rft.atitle=Rebreather+Training+Council.+Mouthpiece+Retraining+Strap+Safety+Guidance+Notice%2C+Issue&rft.date=2023-03-21&rft.aulast=Haynes&rft.aufirst=P&rft.au=Menduno%2C+M&rft.au=Toomer%2C+P&rft_id=https%3A%2F%2Frebreathertrainingcouncil.org%2Fwp-content%2Fuploads%2F2021%2F03%2FRTC-MRS-Guidance-Issue-1-2021-03-23.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Mitchell_2023-38"><span class="mw-cite-backlink"><b><a href="#cite_ref-Mitchell_2023_38-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMitchell2023" class="citation web cs1">Mitchell, Simon (20–22 April 2023). <a rel="nofollow" class="external text" href="https://gue.tv/programs/co2-monitoring-ccr-rebreather-diving-safety">"Developments in CO2 monitoring"</a>. <i>Rebreather Forum 4</i>. Valetta, Malta. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20240416051757/https://gue.tv/programs/co2-monitoring-ccr-rebreather-diving-safety">Archived</a> from the original on 16 April 2024<span class="reference-accessdate">. Retrieved <span class="nowrap">5 June</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=Rebreather+Forum+4&rft.atitle=Developments+in+CO2+monitoring&rft.date=2023-04-20%2F2023-04-22&rft.aulast=Mitchell&rft.aufirst=Simon&rft_id=https%3A%2F%2Fgue.tv%2Fprograms%2Fco2-monitoring-ccr-rebreather-diving-safety&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Kohler_2023-39"><span class="mw-cite-backlink"><b><a href="#cite_ref-Kohler_2023_39-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFKohler2023" class="citation web cs1">Kohler, Richie (20–22 April 2023). <a rel="nofollow" class="external text" href="https://gue.tv/programs/ccr-emergency-procedures-rebreather-diving-safety">"Emergency procedures"</a>. <i>Rebreather Forum 4</i>. Valetta, Malta. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20240603112454/https://gue.tv/programs/ccr-emergency-procedures-rebreather-diving-safety">Archived</a> from the original on 3 June 2024<span class="reference-accessdate">. Retrieved <span class="nowrap">5 June</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=Rebreather+Forum+4&rft.atitle=Emergency+procedures&rft.date=2023-04-20%2F2023-04-22&rft.aulast=Kohler&rft.aufirst=Richie&rft_id=https%3A%2F%2Fgue.tv%2Fprograms%2Fccr-emergency-procedures-rebreather-diving-safety&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Gambin_2023-40"><span class="mw-cite-backlink">^ <a href="#cite_ref-Gambin_2023_40-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Gambin_2023_40-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFGambin2023" class="citation conference cs1">Gambin, Timmy (20–22 April 2023). <a rel="nofollow" class="external text" href="https://gue.tv/programs/ccr-rebreather-diving-malta-shipwrecks"><i>Use Of CCRs In Malta Shipwreck Diving</i></a>. Rebreather Forum 4. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20240601112211/https://gue.tv/programs/ccr-rebreather-diving-malta-shipwrecks">Archived</a> from the original on 1 June 2024<span class="reference-accessdate">. Retrieved <span class="nowrap">1 June</span> 2024</span> – via Global Underwater Explorers.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=conference&rft.btitle=Use+Of+CCRs+In+Malta+Shipwreck+Diving&rft.date=2023-04-20%2F2023-04-22&rft.aulast=Gambin&rft.aufirst=Timmy&rft_id=https%3A%2F%2Fgue.tv%2Fprograms%2Fccr-rebreather-diving-malta-shipwrecks&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Tillmans_2023-41"><span class="mw-cite-backlink">^ <a href="#cite_ref-Tillmans_2023_41-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Tillmans_2023_41-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-Tillmans_2023_41-2"><sup><i><b>c</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFTillmans2023" class="citation web cs1">Tillmans, Frauke (20–22 April 2023). <a rel="nofollow" class="external text" href="https://gue.tv/programs/rebreather-diving-safety-dan-report">"Accident Review: The Safety Situation"</a>. <i>Rebreather Forum 4</i>. Valetta, Malta. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20240501095628/https://gue.tv/programs/rebreather-diving-safety-dan-report">Archived</a> from the original on 1 May 2024<span class="reference-accessdate">. Retrieved <span class="nowrap">1 May</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=Rebreather+Forum+4&rft.atitle=Accident+Review%3A+The+Safety+Situation&rft.date=2023-04-20%2F2023-04-22&rft.aulast=Tillmans&rft.aufirst=Frauke&rft_id=https%3A%2F%2Fgue.tv%2Fprograms%2Frebreather-diving-safety-dan-report&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Deep_Life_Accident_Review-42"><span class="mw-cite-backlink">^ <a href="#cite_ref-Deep_Life_Accident_Review_42-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Deep_Life_Accident_Review_42-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.deeplife.co.uk/or_accident.php">"Deep Life Design Team: databases and analysis of rebreather accident data"</a>. Deeplife.co.uk. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20120827002639/http://www.deeplife.co.uk/or_accident.php">Archived</a> from the original on 27 August 2012<span class="reference-accessdate">. Retrieved <span class="nowrap">31 July</span> 2013</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Deep+Life+Design+Team%3A+databases+and+analysis+of+rebreather+accident+data&rft.pub=Deeplife.co.uk&rft_id=http%3A%2F%2Fwww.deeplife.co.uk%2For_accident.php&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Graham_and_Bozanic_2012-43"><span class="mw-cite-backlink"><b><a href="#cite_ref-Graham_and_Bozanic_2012_43-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFGrahamBozanic2012" class="citation conference cs1">Graham, Danny; Bozanic, Jeffrey E. (18–20 May 2012). Vann, Richard D.; Denoble, Petar J.; Pollock, Neal W. (eds.). <a rel="nofollow" class="external text" href="https://web.archive.org/web/20140717033807/http://media.dan.org/RF3_web.pdf"><i>Prebreathing during closed-circuit diving apparatus set-up ineffective in assessing scrubber efficiency</i></a> <span class="cs1-format">(PDF)</span>. Rebreather Forum 3 Proceedings. Durham, North Carolina: AAUS/DAN/PADI. pp. 268–271. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-9800423-9-9" title="Special:BookSources/978-0-9800423-9-9"><bdi>978-0-9800423-9-9</bdi></a>. Archived from <a rel="nofollow" class="external text" href="http://media.dan.org/RF3_web.pdf">the original</a> <span class="cs1-format">(PDF)</span> on 17 July 2014<span class="reference-accessdate">. Retrieved <span class="nowrap">26 December</span> 2017</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=conference&rft.btitle=Prebreathing+during+closed-circuit+diving+apparatus+set-up+ineffective+in+assessing+scrubber+efficiency&rft.place=Durham%2C+North+Carolina&rft.pages=268-271&rft.pub=AAUS%2FDAN%2FPADI&rft.date=2012-05-18%2F2012-05-20&rft.isbn=978-0-9800423-9-9&rft.aulast=Graham&rft.aufirst=Danny&rft.au=Bozanic%2C+Jeffrey+E.&rft_id=http%3A%2F%2Fmedia.dan.org%2FRF3_web.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Pitkin_2023-44"><span class="mw-cite-backlink">^ <a href="#cite_ref-Pitkin_2023_44-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Pitkin_2023_44-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-Pitkin_2023_44-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-Pitkin_2023_44-3"><sup><i><b>d</b></i></sup></a> <a href="#cite_ref-Pitkin_2023_44-4"><sup><i><b>e</b></i></sup></a> <a href="#cite_ref-Pitkin_2023_44-5"><sup><i><b>f</b></i></sup></a> <a href="#cite_ref-Pitkin_2023_44-6"><sup><i><b>g</b></i></sup></a> <a href="#cite_ref-Pitkin_2023_44-7"><sup><i><b>h</b></i></sup></a> <a href="#cite_ref-Pitkin_2023_44-8"><sup><i><b>i</b></i></sup></a> <a href="#cite_ref-Pitkin_2023_44-9"><sup><i><b>j</b></i></sup></a> <a href="#cite_ref-Pitkin_2023_44-10"><sup><i><b>k</b></i></sup></a> <a href="#cite_ref-Pitkin_2023_44-11"><sup><i><b>l</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFPitkin2023" class="citation web cs1">Pitkin, Andrew (20–22 April 2023). <a rel="nofollow" class="external text" href="https://gue.tv/programs/rebreather-bailout-strategies-technical-diving-ccr-safety">"Bailout strategies"</a>. <i>Rebreather Forum 4</i>. Valetta, Malta. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20240501052433/https://gue.tv/programs/rebreather-bailout-strategies-technical-diving-ccr-safety">Archived</a> from the original on 1 May 2024<span class="reference-accessdate">. Retrieved <span class="nowrap">1 May</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=Rebreather+Forum+4&rft.atitle=Bailout+strategies&rft.date=2023-04-20%2F2023-04-22&rft.aulast=Pitkin&rft.aufirst=Andrew&rft_id=https%3A%2F%2Fgue.tv%2Fprograms%2Frebreather-bailout-strategies-technical-diving-ccr-safety&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Buzzacott_et_al_2022-45"><span class="mw-cite-backlink"><b><a href="#cite_ref-Buzzacott_et_al_2022_45-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFBuzzacottDongBrennerTillmans2022" class="citation journal cs1">Buzzacott, P.; Dong, G.Z.; Brenner, R.J.; Tillmans, F. (30 June 2022). <a rel="nofollow" class="external text" href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9522607">"A survey of caustic cocktail events in rebreather divers"</a>. <i>Diving Hyperb Med</i>. <b>52</b> (2): 92–96. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.28920%2Fdhm52.2.92-96">10.28920/dhm52.2.92-96</a>. <a href="/wiki/PMC_(identifier)" class="mw-redirect" title="PMC (identifier)">PMC</a> <span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9522607">9522607</a></span>. <a href="/wiki/PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/35732280">35732280</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Diving+Hyperb+Med.&rft.atitle=A+survey+of+caustic+cocktail+events+in+rebreather+divers&rft.volume=52&rft.issue=2&rft.pages=92-96&rft.date=2022-06-30&rft_id=https%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fpmc%2Farticles%2FPMC9522607%23id-name%3DPMC&rft_id=info%3Apmid%2F35732280&rft_id=info%3Adoi%2F10.28920%2Fdhm52.2.92-96&rft.aulast=Buzzacott&rft.aufirst=P.&rft.au=Dong%2C+G.Z.&rft.au=Brenner%2C+R.J.&rft.au=Tillmans%2C+F.&rft_id=https%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fpmc%2Farticles%2FPMC9522607&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Simanek-46"><span class="mw-cite-backlink">^ <a href="#cite_ref-Simanek_46-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Simanek_46-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-Simanek_46-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-Simanek_46-3"><sup><i><b>d</b></i></sup></a> <a href="#cite_ref-Simanek_46-4"><sup><i><b>e</b></i></sup></a> <a href="#cite_ref-Simanek_46-5"><sup><i><b>f</b></i></sup></a> <a href="#cite_ref-Simanek_46-6"><sup><i><b>g</b></i></sup></a> <a href="#cite_ref-Simanek_46-7"><sup><i><b>h</b></i></sup></a> <a href="#cite_ref-Simanek_46-8"><sup><i><b>i</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFŠimánek2020" class="citation web cs1">Šimánek, Jakub (10 June 2020). <a rel="nofollow" class="external text" href="https://www.tdisdi.com/tdi-diver-news/using-a-bailout-rebreather/">"Using a Bailout Rebreather"</a>. <i>www.tdisdi.com</i>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20220920171548/https://www.tdisdi.com/tdi-diver-news/using-a-bailout-rebreather/">Archived</a> from the original on 20 September 2022<span class="reference-accessdate">. Retrieved <span class="nowrap">17 September</span> 2022</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=www.tdisdi.com&rft.atitle=Using+a+Bailout+Rebreather&rft.date=2020-06-10&rft.aulast=%C5%A0im%C3%A1nek&rft.aufirst=Jakub&rft_id=https%3A%2F%2Fwww.tdisdi.com%2Ftdi-diver-news%2Fusing-a-bailout-rebreather%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-DANnitrox-47"><span class="mw-cite-backlink"><b><a href="#cite_ref-DANnitrox_47-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFLang2001" class="citation book cs1">Lang, M.A. (2001). <i>DAN nitrox workshop proceedings</i>. Durham, NC: Divers Alert Network. p. 197.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=DAN+nitrox+workshop+proceedings&rft.place=Durham%2C+NC&rft.pages=197&rft.pub=Divers+Alert+Network&rft.date=2001&rft.aulast=Lang&rft.aufirst=M.A.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Divesoft-48"><span class="mw-cite-backlink"><b><a href="#cite_ref-Divesoft_48-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.divesoft.com/en/products/bovdsvadv">"Divesoft BOVs, DSVs and ADVs"</a>. <i>www.divesoft.com</i>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20240206125439/https://www.divesoft.com/en/products/bovdsvadv">Archived</a> from the original on 6 February 2024<span class="reference-accessdate">. Retrieved <span class="nowrap">6 February</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=www.divesoft.com&rft.atitle=Divesoft+BOVs%2C+DSVs+and+ADVs&rft_id=https%3A%2F%2Fwww.divesoft.com%2Fen%2Fproducts%2Fbovdsvadv&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Caney_et_al_2023-49"><span class="mw-cite-backlink">^ <a href="#cite_ref-Caney_et_al_2023_49-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Caney_et_al_2023_49-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-Caney_et_al_2023_49-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-Caney_et_al_2023_49-3"><sup><i><b>d</b></i></sup></a> <a href="#cite_ref-Caney_et_al_2023_49-4"><sup><i><b>e</b></i></sup></a> <a href="#cite_ref-Caney_et_al_2023_49-5"><sup><i><b>f</b></i></sup></a> <a href="#cite_ref-Caney_et_al_2023_49-6"><sup><i><b>g</b></i></sup></a> <a href="#cite_ref-Caney_et_al_2023_49-7"><sup><i><b>h</b></i></sup></a> <a href="#cite_ref-Caney_et_al_2023_49-8"><sup><i><b>i</b></i></sup></a> <a href="#cite_ref-Caney_et_al_2023_49-9"><sup><i><b>j</b></i></sup></a> <a href="#cite_ref-Caney_et_al_2023_49-10"><sup><i><b>k</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFCaneyHarrisonToomer2023" class="citation web cs1">Caney, Mark; Harrison, Sean; Toomer, Paul (20–22 April 2023). <a rel="nofollow" class="external text" href="https://gue.tv/programs/rebreather-diving-education-ccr-training-standards">"CCR Training"</a>. <i>Rebreather Forum 4</i>. Valetta, Malta. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20240501180641/https://gue.tv/programs/rebreather-diving-education-ccr-training-standards">Archived</a> from the original on 1 May 2024<span class="reference-accessdate">. Retrieved <span class="nowrap">1 May</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=Rebreather+Forum+4&rft.atitle=CCR+Training&rft.date=2023-04-20%2F2023-04-22&rft.aulast=Caney&rft.aufirst=Mark&rft.au=Harrison%2C+Sean&rft.au=Toomer%2C+Paul&rft_id=https%3A%2F%2Fgue.tv%2Fprograms%2Frebreather-diving-education-ccr-training-standards&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Ferris_and_Franberg_2023-50"><span class="mw-cite-backlink">^ <a href="#cite_ref-Ferris_and_Franberg_2023_50-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Ferris_and_Franberg_2023_50-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-Ferris_and_Franberg_2023_50-2"><sup><i><b>c</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFFerrisFranberg2023" class="citation web cs1">Ferris, Vince; Franberg, Oscar (20–22 April 2023). <a rel="nofollow" class="external text" href="https://gue.tv/programs/military-diving-with-rebreathers">"Military Diving With Rebreathers"</a>. <i>Rebreather Forum 4</i>. Valetta, Malta. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20240501163809/https://gue.tv/programs/military-diving-with-rebreathers">Archived</a> from the original on 1 May 2024<span class="reference-accessdate">. Retrieved <span class="nowrap">1 May</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=Rebreather+Forum+4&rft.atitle=Military+Diving+With+Rebreathers&rft.date=2023-04-20%2F2023-04-22&rft.aulast=Ferris&rft.aufirst=Vince&rft.au=Franberg%2C+Oscar&rft_id=https%3A%2F%2Fgue.tv%2Fprograms%2Fmilitary-diving-with-rebreathers&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Pollock_et_al_2016-51"><span class="mw-cite-backlink"><b><a href="#cite_ref-Pollock_et_al_2016_51-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFPollockSellersGodfrey2016" class="citation conference cs1">Pollock, Neal W.; Sellers, Steven H.; Godfrey, Jeffrey M. (2016). "Rebreathers and Scientific Diving - Best Practice Recommendations". In Pollock, N.W.; Sellers, S.H.; Godfrey, J.M. (eds.). <a rel="nofollow" class="external text" href="https://s3.amazonaws.com/kajabi-storefronts-production/sites/3839/themes/2022276/downloads/M73b2JtDTTugam7OMZyj_Pollock_-_2016_-_NPSNOAADANAAUS.pdf"><i>Rebreathers and Scientific Diving</i></a> <span class="cs1-format">(PDF)</span>. Proceedings of NPS/NOAA/DAN/AAUS Workshop, 16–19 June 2015. Durham, NC. pp. 1–4. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-9800423-9-9" title="Special:BookSources/978-0-9800423-9-9"><bdi>978-0-9800423-9-9</bdi></a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20220115095434/https://s3.amazonaws.com/kajabi-storefronts-production/sites/3839/themes/2022276/downloads/M73b2JtDTTugam7OMZyj_Pollock_-_2016_-_NPSNOAADANAAUS.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 15 January 2022<span class="reference-accessdate">. Retrieved <span class="nowrap">28 November</span> 2021</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=conference&rft.atitle=Rebreathers+and+Scientific+Diving+-+Best+Practice+Recommendations&rft.btitle=Rebreathers+and+Scientific+Diving.&rft.place=Durham%2C+NC&rft.pages=1-4&rft.date=2016&rft.isbn=978-0-9800423-9-9&rft.aulast=Pollock&rft.aufirst=Neal+W.&rft.au=Sellers%2C+Steven+H.&rft.au=Godfrey%2C+Jeffrey+M.&rft_id=https%3A%2F%2Fs3.amazonaws.com%2Fkajabi-storefronts-production%2Fsites%2F3839%2Fthemes%2F2022276%2Fdownloads%2FM73b2JtDTTugam7OMZyj_Pollock_-_2016_-_NPSNOAADANAAUS.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Kintzing_and_Slattery_2016-52"><span class="mw-cite-backlink">^ <a href="#cite_ref-Kintzing_and_Slattery_2016_52-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Kintzing_and_Slattery_2016_52-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFKintzingSlattery2016" class="citation conference cs1">Kintzing, Elizabeth; Slattery, Marc (2016). "Scientific Rebreather Standards". In Pollock, N.W.; Sellers, S.H.; Godfrey, J.M. (eds.). <a rel="nofollow" class="external text" href="https://s3.amazonaws.com/kajabi-storefronts-production/sites/3839/themes/2022276/downloads/M73b2JtDTTugam7OMZyj_Pollock_-_2016_-_NPSNOAADANAAUS.pdf"><i>Rebreathers and Scientific Diving</i></a> <span class="cs1-format">(PDF)</span>. Proceedings of NPS/NOAA/DAN/AAUS Workshop, 16–19 June 2015. Durham, NC. pp. 80–88. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-9800423-9-9" title="Special:BookSources/978-0-9800423-9-9"><bdi>978-0-9800423-9-9</bdi></a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20220115095434/https://s3.amazonaws.com/kajabi-storefronts-production/sites/3839/themes/2022276/downloads/M73b2JtDTTugam7OMZyj_Pollock_-_2016_-_NPSNOAADANAAUS.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 15 January 2022<span class="reference-accessdate">. Retrieved <span class="nowrap">28 November</span> 2021</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=conference&rft.atitle=Scientific+Rebreather+Standards&rft.btitle=Rebreathers+and+Scientific+Diving.&rft.place=Durham%2C+NC&rft.pages=80-88&rft.date=2016&rft.isbn=978-0-9800423-9-9&rft.aulast=Kintzing&rft.aufirst=Elizabeth&rft.au=Slattery%2C+Marc&rft_id=https%3A%2F%2Fs3.amazonaws.com%2Fkajabi-storefronts-production%2Fsites%2F3839%2Fthemes%2F2022276%2Fdownloads%2FM73b2JtDTTugam7OMZyj_Pollock_-_2016_-_NPSNOAADANAAUS.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-RTC-53"><span class="mw-cite-backlink"><b><a href="#cite_ref-RTC_53-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://rebreathertrainingcouncil.org/">"About the RTC"</a>. <i>rebreathertrainingcouncil.org</i>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20240513214110/https://rebreathertrainingcouncil.org/">Archived</a> from the original on 13 May 2024<span class="reference-accessdate">. Retrieved <span class="nowrap">6 May</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=rebreathertrainingcouncil.org&rft.atitle=About+the+RTC&rft_id=https%3A%2F%2Frebreathertrainingcouncil.org%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-ISO_TC228-54"><span class="mw-cite-backlink"><b><a href="#cite_ref-ISO_TC228_54-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.iso.org/committee/375396.html">"ISO/TC 228 Tourism and related services"</a>. <i>www.iso.org</i>. 27 September 2022. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20240518070644/https://www.iso.org/committee/375396.html">Archived</a> from the original on 18 May 2024<span class="reference-accessdate">. Retrieved <span class="nowrap">6 May</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=www.iso.org&rft.atitle=ISO%2FTC+228+Tourism+and+related+services&rft.date=2022-09-27&rft_id=https%3A%2F%2Fwww.iso.org%2Fcommittee%2F375396.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-RESA-55"><span class="mw-cite-backlink"><b><a href="#cite_ref-RESA_55-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.rebreather.org/">"Home"</a>. <i>www.rebreather.org</i>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20240506085443/https://www.rebreather.org/">Archived</a> from the original on 6 May 2024<span class="reference-accessdate">. Retrieved <span class="nowrap">6 May</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=www.rebreather.org&rft.atitle=Home&rft_id=https%3A%2F%2Fwww.rebreather.org%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-EUF-56"><span class="mw-cite-backlink"><b><a href="#cite_ref-EUF_56-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://euf.eu/en/certification/international-euf-certification">"International EUF Certification"</a>. <i>euf.eu</i>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20240506022218/https://euf.eu/en/certification/international-euf-certification">Archived</a> from the original on 6 May 2024<span class="reference-accessdate">. Retrieved <span class="nowrap">6 May</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=euf.eu&rft.atitle=International+EUF+Certification&rft_id=https%3A%2F%2Feuf.eu%2Fen%2Fcertification%2Finternational-euf-certification&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-InDepth_2023-57"><span class="mw-cite-backlink"><b><a href="#cite_ref-InDepth_2023_57-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFCaney2023" class="citation web cs1">Caney, Mark (October 2023). <a rel="nofollow" class="external text" href="https://indepthmag.com/iso-training-standards-for-rebreather-divers/">"ISO Training Standards for Rebreather Divers"</a>. <i>indepthmag.com/</i>. InDepth. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20240506093005/https://indepthmag.com/iso-training-standards-for-rebreather-divers/">Archived</a> from the original on 6 May 2024<span class="reference-accessdate">. Retrieved <span class="nowrap">6 May</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=indepthmag.com%2F&rft.atitle=ISO+Training+Standards+for+Rebreather+Divers&rft.date=2023-10&rft.aulast=Caney&rft.aufirst=Mark&rft_id=https%3A%2F%2Findepthmag.com%2Fiso-training-standards-for-rebreather-divers%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-davis1955-58"><span class="mw-cite-backlink">^ <a href="#cite_ref-davis1955_58-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-davis1955_58-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-davis1955_58-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-davis1955_58-3"><sup><i><b>d</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFDavis1955" class="citation book cs1"><a href="/wiki/Robert_Davis_(inventor)" title="Robert Davis (inventor)">Davis, R.H.</a> (1955). <i>Deep Diving and Submarine Operations</i> (6th ed.). Tolworth, Surbiton, Surrey: <a href="/wiki/Siebe_Gorman" title="Siebe Gorman">Siebe Gorman & Company Ltd</a>. p. 693.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Deep+Diving+and+Submarine+Operations&rft.place=Tolworth%2C+Surbiton%2C+Surrey&rft.pages=693&rft.edition=6th&rft.pub=Siebe+Gorman+%26+Company+Ltd&rft.date=1955&rft.aulast=Davis&rft.aufirst=R.H.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Quick_1970-59"><span class="mw-cite-backlink">^ <a href="#cite_ref-Quick_1970_59-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Quick_1970_59-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-Quick_1970_59-2"><sup><i><b>c</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFQuick1970" class="citation report cs1">Quick, D. (1970). <a rel="nofollow" class="external text" href="https://web.archive.org/web/20191219194835/http://archive.rubicon-foundation.org/xmlui/bitstream/handle/123456789/4960/RANSUM_Project_1-70.PDF?sequence=1">A History Of Closed Circuit Oxygen Underwater Breathing Apparatus</a> <span class="cs1-format">(PDF)</span>. <i><a href="/wiki/RANSUM" class="mw-redirect" title="RANSUM">RANSUM</a>-1-70</i> (Report). Sydney, Australia: Royal Australian Navy, School of Underwater Medicine. Archived from <a rel="nofollow" class="external text" href="http://archive.rubicon-foundation.org/xmlui/bitstream/handle/123456789/4960/RANSUM_Project_1-70.PDF?sequence=1">the original</a> <span class="cs1-format">(PDF)</span> on 19 December 2019<span class="reference-accessdate">. Retrieved <span class="nowrap">6 February</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=report&rft.btitle=A+History+Of+Closed+Circuit+Oxygen+Underwater+Breathing+Apparatus&rft.place=Sydney%2C+Australia&rft.pub=Royal+Australian+Navy%2C+School+of+Underwater+Medicine.&rft.date=1970&rft.aulast=Quick&rft.aufirst=D.&rft_id=http%3A%2F%2Farchive.rubicon-foundation.org%2Fxmlui%2Fbitstream%2Fhandle%2F123456789%2F4960%2FRANSUM_Project_1-70.PDF%3Fsequence%3D1&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Bjorkman-60"><span class="mw-cite-backlink"><b><a href="#cite_ref-Bjorkman_60-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFBjorkman" class="citation journal cs1">Bjorkman, Bart. <a rel="nofollow" class="external text" href="http://www.advanceddivermagazine.com/articles/guts/guts.html">"Technology and Guts"</a>. <i>Advanced Diver Magazine</i>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20190110125957/http://www.advanceddivermagazine.com/articles/guts/guts.html">Archived</a> from the original on 10 January 2019<span class="reference-accessdate">. Retrieved <span class="nowrap">26 January</span> 2018</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Advanced+Diver+Magazine&rft.atitle=Technology+and+Guts&rft.aulast=Bjorkman&rft.aufirst=Bart&rft_id=http%3A%2F%2Fwww.advanceddivermagazine.com%2Farticles%2Fguts%2Fguts.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Kemp_1990-61"><span class="mw-cite-backlink"><b><a href="#cite_ref-Kemp_1990_61-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFKemp1990" class="citation book cs1">Kemp, Paul (1990). <i>The T-Class submarine – The Classic British Design</i>. Arms and Armour. p. 105. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0853689584" title="Special:BookSources/978-0853689584"><bdi>978-0853689584</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=The+T-Class+submarine+%E2%80%93+The+Classic+British+Design&rft.pages=105&rft.pub=Arms+and+Armour&rft.date=1990&rft.isbn=978-0853689584&rft.aulast=Kemp&rft.aufirst=Paul&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Draegerwerk1899-62"><span class="mw-cite-backlink"><b><a href="#cite_ref-Draegerwerk1899_62-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFDekker" class="citation web cs1">Dekker, David L. <a rel="nofollow" class="external text" href="http://www.divinghelmet.nl/divinghelmet/1899_Draegerwerk.html">"1889. Draegerwerk Lübeck"</a>. <i>Chronology of Diving in Holland</i>. divinghelmet.nl. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20160920034736/http://www.divinghelmet.nl/divinghelmet/1899_Draegerwerk.html">Archived</a> from the original on 20 September 2016<span class="reference-accessdate">. Retrieved <span class="nowrap">14 January</span> 2017</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=Chronology+of+Diving+in+Holland&rft.atitle=1889.+Draegerwerk+L%C3%BCbeck&rft.aulast=Dekker&rft.aufirst=David+L.&rft_id=http%3A%2F%2Fwww.divinghelmet.nl%2Fdivinghelmet%2F1899_Draegerwerk.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-DESCO_29019-63"><span class="mw-cite-backlink"><b><a href="#cite_ref-DESCO_29019_63-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.divedesco.com/P/142/USNavyHeliumMarkVDivingHelmetwDoubleExhaustValveLateVersion">"Commercial Dive Gear » Diving Helmets: DESCO 29019D Mark V Diving Helmet"</a>. Milwaukee, Wisconsin: DESCO Corporation. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20190702054326/https://www.divedesco.com/P/142/USNavyHeliumMarkVDivingHelmetwDoubleExhaustValveLateVersion">Archived</a> from the original on 2 July 2019<span class="reference-accessdate">. Retrieved <span class="nowrap">17 January</span> 2019</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Commercial+Dive+Gear+%C2%BB+Diving+Helmets%3A+DESCO+29019D+Mark+V+Diving+Helmet&rft.place=Milwaukee%2C+Wisconsin&rft.pub=DESCO+Corporation&rft_id=https%3A%2F%2Fwww.divedesco.com%2FP%2F142%2FUSNavyHeliumMarkVDivingHelmetwDoubleExhaustValveLateVersion&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-USNDM_R1-64"><span class="mw-cite-backlink"><b><a href="#cite_ref-USNDM_R1_64-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation book cs1">"12". <a rel="nofollow" class="external text" href="https://apps.dtic.mil/dtic/tr/fulltext/u2/a112710.pdf"><i>US Navy Diving Manual Revision 1 Navsea-0994-LP001-9020</i></a> <span class="cs1-format">(PDF)</span>. Vol. 2. Washington DC: Navy Department. July 1981. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20190702185411/https://apps.dtic.mil/dtic/tr/fulltext/u2/a112710.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 2 July 2019.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=bookitem&rft.atitle=12&rft.btitle=US+Navy+Diving+Manual+Revision+1+Navsea-0994-LP001-9020&rft.place=Washington+DC&rft.pub=Navy+Department&rft.date=1981-07&rft_id=https%3A%2F%2Fapps.dtic.mil%2Fdtic%2Ftr%2Ffulltext%2Fu2%2Fa112710.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Diving_Heritage-65"><span class="mw-cite-backlink"><b><a href="#cite_ref-Diving_Heritage_65-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.divingheritage.com/drager.htm">"Drägerwerk"</a>. <i>Divingheritage.com</i>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20170517132232/http://www.divingheritage.com/drager.htm">Archived</a> from the original on 17 May 2017<span class="reference-accessdate">. Retrieved <span class="nowrap">17 October</span> 2021</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=Divingheritage.com&rft.atitle=Dr%C3%A4gerwerk&rft_id=http%3A%2F%2Fwww.divingheritage.com%2Fdrager.htm&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Pirelli-66"><span class="mw-cite-backlink"><b><a href="#cite_ref-Pirelli_66-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMarí" class="citation web cs1">Marí, Alejandro Sergio. Bech, Janwillem (ed.). <a rel="nofollow" class="external text" href="http://www.therebreathersite.nl/Zuurstofrebreathers/Italian/pirelli_aro_ww_ii.htm">"The Pirelli Aro WWII"</a>. <i>therebreathersite.nl</i>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20160923065105/http://www.therebreathersite.nl/Zuurstofrebreathers/Italian/pirelli_aro_ww_ii.htm">Archived</a> from the original on 23 September 2016<span class="reference-accessdate">. Retrieved <span class="nowrap">17 October</span> 2021</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=therebreathersite.nl&rft.atitle=The+Pirelli+Aro+WWII&rft.aulast=Mar%C3%AD&rft.aufirst=Alejandro+Sergio&rft_id=http%3A%2F%2Fwww.therebreathersite.nl%2FZuurstofrebreathers%2FItalian%2Fpirelli_aro_ww_ii.htm&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Shapiro-67"><span class="mw-cite-backlink"><b><a href="#cite_ref-Shapiro_67-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFShapiro2011" class="citation news cs1">Shapiro, T. Rees (19 February 2011). <a rel="nofollow" class="external text" href="https://www.washingtonpost.com/wp-dyn/content/article/2011/02/18/AR2011021802873.html">"Christian J. Lambertsen, OSS officer who created early scuba device, dies at 93"</a>. <i>The Washington Post</i>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20180720194920/http://www.washingtonpost.com/wp-dyn/content/article/2011/02/18/AR2011021802873.html">Archived</a> from the original on 20 July 2018<span class="reference-accessdate">. Retrieved <span class="nowrap">17 October</span> 2021</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=The+Washington+Post&rft.atitle=Christian+J.+Lambertsen%2C+OSS+officer+who+created+early+scuba+device%2C+dies+at+93&rft.date=2011-02-19&rft.aulast=Shapiro&rft.aufirst=T.+Rees&rft_id=https%3A%2F%2Fwww.washingtonpost.com%2Fwp-dyn%2Fcontent%2Farticle%2F2011%2F02%2F18%2FAR2011021802873.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-patent-68"><span class="mw-cite-backlink"><b><a href="#cite_ref-patent_68-0">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="https://www.google.com/patents/about?id=5PRKAAAAEBAJ">1944 Lambertsen's <i>breathing apparatus</i> patent in <i>Google Patents</i></a><sup class="noprint Inline-Template"><span style="white-space: nowrap;">[<i><a href="/wiki/Wikipedia:Link_rot" title="Wikipedia:Link rot"><span title=" Dead link tagged June 2024">dead link</span></a></i><span style="visibility:hidden; color:transparent; padding-left:2px">‍</span>]</span></sup></span> </li> <li id="cite_note-Brubakk_2003-69"><span class="mw-cite-backlink"><b><a href="#cite_ref-Brubakk_2003_69-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFBrubakkNeuman2003" class="citation book cs1">Brubakk, Alf O.; Neuman, Tom S., eds. (2003). <i>Bennett and Elliott's physiology and medicine of diving</i> (5th Rev ed.). Philadelphia, Pennsylvania: Saunders Ltd. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0702025716" title="Special:BookSources/978-0702025716"><bdi>978-0702025716</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Bennett+and+Elliott%27s+physiology+and+medicine+of+diving&rft.place=Philadelphia%2C+Pennsylvania&rft.edition=5th+Rev&rft.pub=Saunders+Ltd.&rft.date=2003&rft.isbn=978-0702025716&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Vann_2004-70"><span class="mw-cite-backlink"><b><a href="#cite_ref-Vann_2004_70-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFVann2004" class="citation journal cs1">Vann, R.D. (2004). "Lambertsen and O2: beginnings of operational physiology". <i>Undersea Hyperb Med</i>. <b>31</b> (1): 21–31. <a href="/wiki/PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/15233157">15233157</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Undersea+Hyperb+Med&rft.atitle=Lambertsen+and+O2%3A+beginnings+of+operational+physiology&rft.volume=31&rft.issue=1&rft.pages=21-31&rft.date=2004&rft_id=info%3Apmid%2F15233157&rft.aulast=Vann&rft.aufirst=R.D.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Butler_2004-71"><span class="mw-cite-backlink"><b><a href="#cite_ref-Butler_2004_71-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFButler2004" class="citation journal cs1">Butler, F.K. (2004). "Closed-circuit oxygen diving in the U.S. Navy". <i>Journal of Undersea and Hyperbaric Medicine</i>. <b>31</b> (1). Bethesda, Maryland: Undersea and Hyperbaric Medicine Society: 3–20. <a href="/wiki/PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/15233156">15233156</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Journal+of+Undersea+and+Hyperbaric+Medicine&rft.atitle=Closed-circuit+oxygen+diving+in+the+U.S.+Navy&rft.volume=31&rft.issue=1&rft.pages=3-20&rft.date=2004&rft_id=info%3Apmid%2F15233156&rft.aulast=Butler&rft.aufirst=F.K.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-oxford-72"><span class="mw-cite-backlink"><b><a href="#cite_ref-oxford_72-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20160925160356/https://en.oxforddictionaries.com/definition/scuba">"Definition of <i>scuba</i> in English"</a>. Oxford University Press. Archived from <a rel="nofollow" class="external text" href="https://en.oxforddictionaries.com/definition/scuba">the original</a> on 25 September 2016.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Definition+of+scuba+in+English&rft.pub=Oxford+University+Press&rft_id=https%3A%2F%2Fen.oxforddictionaries.com%2Fdefinition%2Fscuba&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Menduno_2019_part3-73"><span class="mw-cite-backlink">^ <a href="#cite_ref-Menduno_2019_part3_73-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Menduno_2019_part3_73-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-Menduno_2019_part3_73-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-Menduno_2019_part3_73-3"><sup><i><b>d</b></i></sup></a> <a href="#cite_ref-Menduno_2019_part3_73-4"><sup><i><b>e</b></i></sup></a> <a href="#cite_ref-Menduno_2019_part3_73-5"><sup><i><b>f</b></i></sup></a> <a href="#cite_ref-Menduno_2019_part3_73-6"><sup><i><b>g</b></i></sup></a> <a href="#cite_ref-Menduno_2019_part3_73-7"><sup><i><b>h</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMenduno2019" class="citation web cs1">Menduno, Michael (August 2019). <a rel="nofollow" class="external text" href="https://divernet.com/2019/09/12/the-technical-diving-revolution-part-3/">"The Technical Diving Revolution – part 3"</a>. DIVER Magazine. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20210930104417/https://divernet.com/2019/09/12/the-technical-diving-revolution-part-3/">Archived</a> from the original on 30 September 2021<span class="reference-accessdate">. Retrieved <span class="nowrap">1 October</span> 2021</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=The+Technical+Diving+Revolution+%E2%80%93+part+3&rft.pub=DIVER+Magazine&rft.date=2019-08&rft.aulast=Menduno&rft.aufirst=Michael&rft_id=https%3A%2F%2Fdivernet.com%2F2019%2F09%2F12%2Fthe-technical-diving-revolution-part-3%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Menduno_2023-74"><span class="mw-cite-backlink">^ <a href="#cite_ref-Menduno_2023_74-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Menduno_2023_74-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-Menduno_2023_74-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-Menduno_2023_74-3"><sup><i><b>d</b></i></sup></a> <a href="#cite_ref-Menduno_2023_74-4"><sup><i><b>e</b></i></sup></a> <a href="#cite_ref-Menduno_2023_74-5"><sup><i><b>f</b></i></sup></a> <a href="#cite_ref-Menduno_2023_74-6"><sup><i><b>g</b></i></sup></a> <a href="#cite_ref-Menduno_2023_74-7"><sup><i><b>h</b></i></sup></a> <a href="#cite_ref-Menduno_2023_74-8"><sup><i><b>i</b></i></sup></a> <a href="#cite_ref-Menduno_2023_74-9"><sup><i><b>j</b></i></sup></a> <a href="#cite_ref-Menduno_2023_74-10"><sup><i><b>k</b></i></sup></a> <a href="#cite_ref-Menduno_2023_74-11"><sup><i><b>l</b></i></sup></a> <a href="#cite_ref-Menduno_2023_74-12"><sup><i><b>m</b></i></sup></a> <a href="#cite_ref-Menduno_2023_74-13"><sup><i><b>n</b></i></sup></a> <a href="#cite_ref-Menduno_2023_74-14"><sup><i><b>o</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMenduno2023" class="citation web cs1">Menduno, Michael (20–22 April 2023). <a rel="nofollow" class="external text" href="https://gue.tv/programs/rebreather-diver-safety-ccr-checklists-equipment">"Overview of Rebreather Diving"</a>. <i>Rebreather Forum 4</i>. Valetta, Malta. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20240605073737/https://gue.tv/programs/rebreather-diver-safety-ccr-checklists-equipment">Archived</a> from the original on 5 June 2024<span class="reference-accessdate">. Retrieved <span class="nowrap">5 June</span> 2024</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=Rebreather+Forum+4&rft.atitle=Overview+of+Rebreather+Diving&rft.date=2023-04-20%2F2023-04-22&rft.aulast=Menduno&rft.aufirst=Michael&rft_id=https%3A%2F%2Fgue.tv%2Fprograms%2Frebreather-diver-safety-ccr-checklists-equipment&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Pyle_et_al_2016-75"><span class="mw-cite-backlink">^ <a href="#cite_ref-Pyle_et_al_2016_75-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Pyle_et_al_2016_75-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-Pyle_et_al_2016_75-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-Pyle_et_al_2016_75-3"><sup><i><b>d</b></i></sup></a> <a href="#cite_ref-Pyle_et_al_2016_75-4"><sup><i><b>e</b></i></sup></a> <a href="#cite_ref-Pyle_et_al_2016_75-5"><sup><i><b>f</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFPyleLobelTomoleoni2016" class="citation conference cs1">Pyle, Richard L.; Lobel, Phillip S.; Tomoleoni, Joseph A. (2016). "The Value of Closed-Circuit Rebreathers for Biological Research". In Pollock, N.W.; Sellers, S.H.; Godfrey, J.M. (eds.). <a rel="nofollow" class="external text" href="https://s3.amazonaws.com/kajabi-storefronts-production/sites/3839/themes/2022276/downloads/M73b2JtDTTugam7OMZyj_Pollock_-_2016_-_NPSNOAADANAAUS.pdf"><i>Rebreathers and Scientific Diving</i></a> <span class="cs1-format">(PDF)</span>. Proceedings of NPS/NOAA/DAN/AAUS Workshop, 16–19 June 2015. Durham, NC. pp. 120–134. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-9800423-9-9" title="Special:BookSources/978-0-9800423-9-9"><bdi>978-0-9800423-9-9</bdi></a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20220115095434/https://s3.amazonaws.com/kajabi-storefronts-production/sites/3839/themes/2022276/downloads/M73b2JtDTTugam7OMZyj_Pollock_-_2016_-_NPSNOAADANAAUS.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 15 January 2022<span class="reference-accessdate">. Retrieved <span class="nowrap">28 November</span> 2021</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=conference&rft.atitle=The+Value+of+Closed-Circuit+Rebreathers+for+Biological+Research&rft.btitle=Rebreathers+and+Scientific+Diving.&rft.place=Durham%2C+NC&rft.pages=120-134&rft.date=2016&rft.isbn=978-0-9800423-9-9&rft.aulast=Pyle&rft.aufirst=Richard+L.&rft.au=Lobel%2C+Phillip+S.&rft.au=Tomoleoni%2C+Joseph+A.&rft_id=https%3A%2F%2Fs3.amazonaws.com%2Fkajabi-storefronts-production%2Fsites%2F3839%2Fthemes%2F2022276%2Fdownloads%2FM73b2JtDTTugam7OMZyj_Pollock_-_2016_-_NPSNOAADANAAUS.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Sellers_2016-76"><span class="mw-cite-backlink">^ <a href="#cite_ref-Sellers_2016_76-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Sellers_2016_76-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFSellers2016" class="citation conference cs1">Sellers, Steven H. (2016). "An Overview of Rebreathers in Scientific Diving 1998–2013". In Pollock, N.W.; Sellers, S.H.; Godfrey, J.M. (eds.). <a rel="nofollow" class="external text" href="https://s3.amazonaws.com/kajabi-storefronts-production/sites/3839/themes/2022276/downloads/M73b2JtDTTugam7OMZyj_Pollock_-_2016_-_NPSNOAADANAAUS.pdf"><i>Rebreathers and Scientific Diving</i></a> <span class="cs1-format">(PDF)</span>. Proceedings of NPS/NOAA/DAN/AAUS Workshop, 16–19 June 2015. Durham, NC. pp. 5–39. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-9800423-9-9" title="Special:BookSources/978-0-9800423-9-9"><bdi>978-0-9800423-9-9</bdi></a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20220115095434/https://s3.amazonaws.com/kajabi-storefronts-production/sites/3839/themes/2022276/downloads/M73b2JtDTTugam7OMZyj_Pollock_-_2016_-_NPSNOAADANAAUS.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 15 January 2022<span class="reference-accessdate">. Retrieved <span class="nowrap">28 November</span> 2021</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=conference&rft.atitle=An+Overview+of+Rebreathers+in+Scientific+Diving+1998%E2%80%932013&rft.btitle=Rebreathers+and+Scientific+Diving.&rft.place=Durham%2C+NC&rft.pages=5-39&rft.date=2016&rft.isbn=978-0-9800423-9-9&rft.aulast=Sellers&rft.aufirst=Steven+H.&rft_id=https%3A%2F%2Fs3.amazonaws.com%2Fkajabi-storefronts-production%2Fsites%2F3839%2Fthemes%2F2022276%2Fdownloads%2FM73b2JtDTTugam7OMZyj_Pollock_-_2016_-_NPSNOAADANAAUS.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Kesling_2016-77"><span class="mw-cite-backlink"><b><a href="#cite_ref-Kesling_2016_77-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFKesling2016" class="citation conference cs1">Kesling, Douglas E. (2016). "Operational Considerations for the Use of Closed-Circuit Rebreathers in Scientific Diving Research". In Pollock, N.W.; Sellers, S.H.; Godfrey, J.M. (eds.). <a rel="nofollow" class="external text" href="https://s3.amazonaws.com/kajabi-storefronts-production/sites/3839/themes/2022276/downloads/M73b2JtDTTugam7OMZyj_Pollock_-_2016_-_NPSNOAADANAAUS.pdf"><i>Rebreathers and Scientific Diving</i></a> <span class="cs1-format">(PDF)</span>. Proceedings of NPS/NOAA/DAN/AAUS Workshop, 16–19 June 2015. Durham, NC. pp. 89–110. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-9800423-9-9" title="Special:BookSources/978-0-9800423-9-9"><bdi>978-0-9800423-9-9</bdi></a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20220115095434/https://s3.amazonaws.com/kajabi-storefronts-production/sites/3839/themes/2022276/downloads/M73b2JtDTTugam7OMZyj_Pollock_-_2016_-_NPSNOAADANAAUS.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 15 January 2022<span class="reference-accessdate">. Retrieved <span class="nowrap">28 November</span> 2021</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=conference&rft.atitle=Operational+Considerations+for+the+Use+of+Closed-Circuit+Rebreathers+in+Scientific+Diving+Research&rft.btitle=Rebreathers+and+Scientific+Diving.&rft.place=Durham%2C+NC&rft.pages=89-110&rft.date=2016&rft.isbn=978-0-9800423-9-9&rft.aulast=Kesling&rft.aufirst=Douglas+E.&rft_id=https%3A%2F%2Fs3.amazonaws.com%2Fkajabi-storefronts-production%2Fsites%2F3839%2Fthemes%2F2022276%2Fdownloads%2FM73b2JtDTTugam7OMZyj_Pollock_-_2016_-_NPSNOAADANAAUS.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Short_2016-78"><span class="mw-cite-backlink">^ <a href="#cite_ref-Short_2016_78-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Short_2016_78-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFShort2016" class="citation conference cs1">Short, Phillip A. (2016). "Emergency Procedures and Managing a Rebreather Whilst Task Loaded: The Implementation of Rebreather Technology into Scientific Diving Projects". In Pollock, N.W.; Sellers, S.H.; Godfrey, J.M. (eds.). <a rel="nofollow" class="external text" href="https://s3.amazonaws.com/kajabi-storefronts-production/sites/3839/themes/2022276/downloads/M73b2JtDTTugam7OMZyj_Pollock_-_2016_-_NPSNOAADANAAUS.pdf"><i>Rebreathers and Scientific Diving</i></a> <span class="cs1-format">(PDF)</span>. Proceedings of NPS/NOAA/DAN/AAUS Workshop, 16–19 June 2015. Durham, NC. pp. 111–119. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-9800423-9-9" title="Special:BookSources/978-0-9800423-9-9"><bdi>978-0-9800423-9-9</bdi></a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20220115095434/https://s3.amazonaws.com/kajabi-storefronts-production/sites/3839/themes/2022276/downloads/M73b2JtDTTugam7OMZyj_Pollock_-_2016_-_NPSNOAADANAAUS.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 15 January 2022<span class="reference-accessdate">. Retrieved <span class="nowrap">28 November</span> 2021</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=conference&rft.atitle=Emergency+Procedures+and+Managing+a+Rebreather+Whilst+Task+Loaded%3A+The+Implementation+of+Rebreather+Technology+into+Scientific+Diving+Projects&rft.btitle=Rebreathers+and+Scientific+Diving.&rft.place=Durham%2C+NC&rft.pages=111-119&rft.date=2016&rft.isbn=978-0-9800423-9-9&rft.aulast=Short&rft.aufirst=Phillip+A.&rft_id=https%3A%2F%2Fs3.amazonaws.com%2Fkajabi-storefronts-production%2Fsites%2F3839%2Fthemes%2F2022276%2Fdownloads%2FM73b2JtDTTugam7OMZyj_Pollock_-_2016_-_NPSNOAADANAAUS.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> <li id="cite_note-Seymour_2016-79"><span class="mw-cite-backlink">^ <a href="#cite_ref-Seymour_2016_79-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Seymour_2016_79-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFSeymour2016" class="citation conference cs1">Seymour, Brett T. (2016). "Mixed Mode and Mixed Platform Diving". In Pollock, N.W.; Sellers, S.H.; Godfrey, J.M. (eds.). <a rel="nofollow" class="external text" href="https://s3.amazonaws.com/kajabi-storefronts-production/sites/3839/themes/2022276/downloads/M73b2JtDTTugam7OMZyj_Pollock_-_2016_-_NPSNOAADANAAUS.pdf"><i>Rebreathers and Scientific Diving</i></a> <span class="cs1-format">(PDF)</span>. Proceedings of NPS/NOAA/DAN/AAUS Workshop, 16–19 June 2015. Durham, NC. pp. 135–144. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-9800423-9-9" title="Special:BookSources/978-0-9800423-9-9"><bdi>978-0-9800423-9-9</bdi></a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20220115095434/https://s3.amazonaws.com/kajabi-storefronts-production/sites/3839/themes/2022276/downloads/M73b2JtDTTugam7OMZyj_Pollock_-_2016_-_NPSNOAADANAAUS.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 15 January 2022<span class="reference-accessdate">. Retrieved <span class="nowrap">28 November</span> 2021</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=conference&rft.atitle=Mixed+Mode+and+Mixed+Platform+Diving&rft.btitle=Rebreathers+and+Scientific+Diving.&rft.place=Durham%2C+NC&rft.pages=135-144&rft.date=2016&rft.isbn=978-0-9800423-9-9&rft.aulast=Seymour&rft.aufirst=Brett+T.&rft_id=https%3A%2F%2Fs3.amazonaws.com%2Fkajabi-storefronts-production%2Fsites%2F3839%2Fthemes%2F2022276%2Fdownloads%2FM73b2JtDTTugam7OMZyj_Pollock_-_2016_-_NPSNOAADANAAUS.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ARebreather+diving" class="Z3988"></span></span> </li> </ol></div></div> <div class="mw-heading mw-heading3"><h3 id="Sources">Sources</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=85" title="Edit section: Sources"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a rel="nofollow" class="external text" href="http://www.teknosofen.com/index.htm">Teknosofen homepage</a> Åke's Rebreather Related Page</li></ul> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Rebreather_diving&action=edit&section=86" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a rel="nofollow" class="external text" href="http://www.RebreatherWorld.com">Rebreather Scuba Diving</a> Rebreather world contains further information on rebreathers.</li></ul> <div class="navbox-styles"><style data-mw-deduplicate="TemplateStyles:r1129693374">.mw-parser-output .hlist dl,.mw-parser-output .hlist ol,.mw-parser-output .hlist ul{margin:0;padding:0}.mw-parser-output .hlist dd,.mw-parser-output .hlist dt,.mw-parser-output .hlist li{margin:0;display:inline}.mw-parser-output .hlist.inline,.mw-parser-output .hlist.inline dl,.mw-parser-output .hlist.inline ol,.mw-parser-output .hlist.inline ul,.mw-parser-output .hlist dl dl,.mw-parser-output .hlist dl ol,.mw-parser-output .hlist dl ul,.mw-parser-output .hlist ol dl,.mw-parser-output .hlist ol ol,.mw-parser-output .hlist ol ul,.mw-parser-output .hlist ul dl,.mw-parser-output .hlist ul ol,.mw-parser-output .hlist ul ul{display:inline}.mw-parser-output .hlist .mw-empty-li{display:none}.mw-parser-output .hlist dt::after{content:": "}.mw-parser-output .hlist dd::after,.mw-parser-output .hlist li::after{content:" · ";font-weight:bold}.mw-parser-output .hlist dd:last-child::after,.mw-parser-output .hlist dt:last-child::after,.mw-parser-output .hlist li:last-child::after{content:none}.mw-parser-output .hlist dd dd:first-child::before,.mw-parser-output .hlist dd dt:first-child::before,.mw-parser-output .hlist dd li:first-child::before,.mw-parser-output .hlist dt dd:first-child::before,.mw-parser-output .hlist dt dt:first-child::before,.mw-parser-output .hlist dt li:first-child::before,.mw-parser-output .hlist li dd:first-child::before,.mw-parser-output .hlist li dt:first-child::before,.mw-parser-output .hlist li li:first-child::before{content:" (";font-weight:normal}.mw-parser-output .hlist dd dd:last-child::after,.mw-parser-output .hlist dd dt:last-child::after,.mw-parser-output .hlist dd li:last-child::after,.mw-parser-output .hlist dt dd:last-child::after,.mw-parser-output .hlist dt dt:last-child::after,.mw-parser-output .hlist dt li:last-child::after,.mw-parser-output .hlist li dd:last-child::after,.mw-parser-output .hlist li dt:last-child::after,.mw-parser-output .hlist li li:last-child::after{content:")";font-weight:normal}.mw-parser-output .hlist ol{counter-reset:listitem}.mw-parser-output .hlist ol>li{counter-increment:listitem}.mw-parser-output .hlist ol>li::before{content:" "counter(listitem)"\a0 "}.mw-parser-output .hlist dd ol>li:first-child::before,.mw-parser-output .hlist dt ol>li:first-child::before,.mw-parser-output .hlist li ol>li:first-child::before{content:" ("counter(listitem)"\a0 "}</style><style data-mw-deduplicate="TemplateStyles:r1236075235">.mw-parser-output .navbox{box-sizing:border-box;border:1px solid #a2a9b1;width:100%;clear:both;font-size:88%;text-align:center;padding:1px;margin:1em auto 0}.mw-parser-output .navbox .navbox{margin-top:0}.mw-parser-output .navbox+.navbox,.mw-parser-output .navbox+.navbox-styles+.navbox{margin-top:-1px}.mw-parser-output .navbox-inner,.mw-parser-output .navbox-subgroup{width:100%}.mw-parser-output .navbox-group,.mw-parser-output .navbox-title,.mw-parser-output .navbox-abovebelow{padding:0.25em 1em;line-height:1.5em;text-align:center}.mw-parser-output .navbox-group{white-space:nowrap;text-align:right}.mw-parser-output .navbox,.mw-parser-output .navbox-subgroup{background-color:#fdfdfd}.mw-parser-output .navbox-list{line-height:1.5em;border-color:#fdfdfd}.mw-parser-output .navbox-list-with-group{text-align:left;border-left-width:2px;border-left-style:solid}.mw-parser-output tr+tr>.navbox-abovebelow,.mw-parser-output tr+tr>.navbox-group,.mw-parser-output tr+tr>.navbox-image,.mw-parser-output tr+tr>.navbox-list{border-top:2px solid #fdfdfd}.mw-parser-output .navbox-title{background-color:#ccf}.mw-parser-output .navbox-abovebelow,.mw-parser-output .navbox-group,.mw-parser-output .navbox-subgroup .navbox-title{background-color:#ddf}.mw-parser-output .navbox-subgroup .navbox-group,.mw-parser-output .navbox-subgroup .navbox-abovebelow{background-color:#e6e6ff}.mw-parser-output .navbox-even{background-color:#f7f7f7}.mw-parser-output .navbox-odd{background-color:transparent}.mw-parser-output .navbox .hlist td dl,.mw-parser-output .navbox .hlist td ol,.mw-parser-output .navbox .hlist td ul,.mw-parser-output .navbox td.hlist dl,.mw-parser-output .navbox td.hlist ol,.mw-parser-output .navbox td.hlist ul{padding:0.125em 0}.mw-parser-output .navbox .navbar{display:block;font-size:100%}.mw-parser-output .navbox-title .navbar{float:left;text-align:left;margin-right:0.5em}body.skin--responsive .mw-parser-output .navbox-image img{max-width:none!important}@media print{body.ns-0 .mw-parser-output .navbox{display:none!important}}</style></div><div role="navigation" class="navbox" aria-labelledby="Underwater_diving" style="padding:3px"><table class="nowraplinks hlist mw-collapsible mw-collapsed navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><style data-mw-deduplicate="TemplateStyles:r1239400231">.mw-parser-output .navbar{display:inline;font-size:88%;font-weight:normal}.mw-parser-output .navbar-collapse{float:left;text-align:left}.mw-parser-output .navbar-boxtext{word-spacing:0}.mw-parser-output .navbar ul{display:inline-block;white-space:nowrap;line-height:inherit}.mw-parser-output .navbar-brackets::before{margin-right:-0.125em;content:"[ "}.mw-parser-output .navbar-brackets::after{margin-left:-0.125em;content:" ]"}.mw-parser-output .navbar li{word-spacing:-0.125em}.mw-parser-output .navbar a>span,.mw-parser-output .navbar a>abbr{text-decoration:inherit}.mw-parser-output .navbar-mini abbr{font-variant:small-caps;border-bottom:none;text-decoration:none;cursor:inherit}.mw-parser-output .navbar-ct-full{font-size:114%;margin:0 7em}.mw-parser-output .navbar-ct-mini{font-size:114%;margin:0 4em}html.skin-theme-clientpref-night .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}@media(prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}}@media print{.mw-parser-output .navbar{display:none!important}}</style><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Underwater_diving" title="Template:Underwater diving"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Underwater_diving" title="Template talk:Underwater diving"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Underwater_diving" title="Special:EditPage/Template:Underwater diving"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Underwater_diving" style="font-size:114%;margin:0 4em"><a href="/wiki/Underwater_diving" title="Underwater diving">Underwater diving</a></div></th></tr><tr><td class="navbox-abovebelow" colspan="2"><div> <ul><li><a href="/wiki/Diving_activities" title="Diving activities">Diving activities</a></li> <li><a href="/wiki/Diving_mode" class="mw-redirect" title="Diving mode">Diving modes</a> <ul><li><a href="/wiki/Atmospheric_pressure_diving" class="mw-redirect" title="Atmospheric pressure diving">Atmospheric pressure diving</a></li> <li><a href="/wiki/Freediving" title="Freediving">Freediving</a></li> <li><a href="/wiki/Saturation_diving" title="Saturation diving">Saturation diving</a></li> <li><a href="/wiki/Scuba_diving" title="Scuba diving">Scuba diving</a></li> <li><a href="/wiki/Snorkeling" title="Snorkeling">Snorkeling</a></li> <li><a href="/wiki/Surface_oriented_diving" class="mw-redirect" title="Surface oriented diving">Surface oriented diving</a></li> <li><a href="/wiki/Surface-supplied_diving" title="Surface-supplied diving">Surface-supplied diving</a></li> <li><a href="/wiki/Unmanned_diving" class="mw-redirect" title="Unmanned diving">Unmanned diving</a></li></ul></li></ul> </div></td></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks mw-collapsible mw-collapsed navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><div id="Diving_equipment" style="font-size:114%;margin:0 4em"><a href="/wiki/Diving_equipment" title="Diving equipment">Diving equipment</a></div></th></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Cleaning_and_disinfection_of_personal_diving_equipment" title="Cleaning and disinfection of personal diving equipment">Cleaning and disinfection of personal diving equipment</a></li> <li><a href="/wiki/Human_factors_in_diving_equipment_design" title="Human factors in diving equipment design">Human factors in diving equipment design</a></li> <li><a href="/wiki/List_of_diving_equipment_manufacturers" title="List of diving equipment manufacturers">List of diving equipment manufacturers</a></li></ul> </div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">Basic equipment</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Diving_mask" title="Diving mask">Diving mask</a></li> <li><a href="/wiki/Snorkel_(swimming)" title="Snorkel (swimming)">Snorkel</a></li> <li><a href="/wiki/Swimfin" title="Swimfin">Swimfin</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Breathing_gas" title="Breathing gas">Breathing gas</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Bailout_gas" class="mw-redirect" title="Bailout gas">Bailout gas</a></li> <li><a href="/wiki/Bottom_gas" class="mw-redirect" title="Bottom gas">Bottom gas</a></li> <li><a href="/wiki/Breathing_air" class="mw-redirect" title="Breathing air">Breathing air</a></li> <li><a href="/wiki/Decompression_gas" class="mw-redirect" title="Decompression gas">Decompression gas</a></li> <li><a href="/wiki/Emergency_gas_supply" class="mw-redirect" title="Emergency gas supply">Emergency gas supply</a></li> <li><a href="/wiki/Heliox" title="Heliox">Heliox</a></li> <li><a href="/wiki/Hydreliox" title="Hydreliox">Hydreliox</a></li> <li><a href="/wiki/Hydrox_(breathing_gas)" title="Hydrox (breathing gas)">Hydrox</a></li> <li><a href="/wiki/Nitrox" title="Nitrox">Nitrox</a></li> <li><a href="/wiki/Oxygen" title="Oxygen">Oxygen</a></li> <li><a href="/wiki/Travel_gas" class="mw-redirect" title="Travel gas">Travel gas</a></li> <li><a href="/wiki/Trimix_(breathing_gas)" title="Trimix (breathing gas)">Trimix</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Buoyancy and<br />trim equipment</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Avelo_diving_system" title="Avelo diving system">Avelo diving system</a></li> <li><a href="/wiki/Buoyancy_compensator_(diving)" title="Buoyancy compensator (diving)">Buoyancy compensator</a> <ul><li><a href="/wiki/Power_inflator" class="mw-redirect" title="Power inflator">Power inflator</a></li> <li><a href="/wiki/Dump_valve_(diving)" class="mw-redirect" title="Dump valve (diving)">Dump valve</a></li> <li><a href="/wiki/Variable_buoyancy_pressure_vessel" class="mw-redirect" title="Variable buoyancy pressure vessel">Variable buoyancy pressure vessel</a></li></ul></li> <li><a href="/wiki/Diving_weighting_system" title="Diving weighting system">Diving weighting system</a> <ul><li><a href="/wiki/Ankle_weights_(diving)" class="mw-redirect" title="Ankle weights (diving)">Ankle weights</a></li> <li><a href="/wiki/Integrated_weights" class="mw-redirect" title="Integrated weights">Integrated weights</a></li> <li><a href="/wiki/Trim_weights_(diving)" class="mw-redirect" title="Trim weights (diving)">Trim weights</a></li> <li><a href="/wiki/Weight_belt" class="mw-redirect" title="Weight belt">Weight belt</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Decompression_equipment" title="Decompression equipment">Decompression<br />equipment</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Decompression_buoy" class="mw-redirect" title="Decompression buoy">Decompression buoy</a></li> <li><a href="/wiki/Decompression_chamber" class="mw-redirect" title="Decompression chamber">Decompression chamber</a></li> <li><a href="/wiki/Decompression_cylinder" class="mw-redirect" title="Decompression cylinder">Decompression cylinder</a></li> <li><a href="/wiki/Decompression_trapeze" class="mw-redirect" title="Decompression trapeze">Decompression trapeze</a></li> <li><a href="/wiki/Dive_computer" title="Dive computer">Dive computer</a></li> <li><a href="/wiki/Diving_bell" title="Diving bell">Diving bell</a></li> <li><a href="/wiki/Diving_shot" title="Diving shot">Diving shot</a></li> <li><a href="/wiki/Diving_stage" class="mw-redirect" title="Diving stage">Diving stage</a></li> <li><a href="/wiki/Jersey_upline" class="mw-redirect" title="Jersey upline">Jersey upline</a></li> <li><a href="/wiki/Jonline" class="mw-redirect" title="Jonline">Jonline</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Diving_suit" title="Diving suit">Diving suit</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Atmospheric_diving_suit" title="Atmospheric diving suit">Atmospheric diving suit</a> <ul><li><a href="/wiki/JIM_suit" title="JIM suit">JIM suit</a></li> <li><a href="/wiki/Newtsuit" title="Newtsuit">Newtsuit</a></li></ul></li> <li><a href="/wiki/Dry_suit" title="Dry suit">Dry suit</a> <ul><li><a href="/wiki/Sladen_suit" class="mw-redirect" title="Sladen suit">Sladen suit</a></li> <li><a href="/wiki/Standard_diving_suit" class="mw-redirect" title="Standard diving suit">Standard diving suit</a></li></ul></li> <li><a href="/wiki/Rash_vest" class="mw-redirect" title="Rash vest">Rash vest</a></li> <li><a href="/wiki/Wetsuit" title="Wetsuit">Wetsuit</a> <ul><li><a href="/wiki/Dive_skins" class="mw-redirect" title="Dive skins">Dive skins</a></li> <li><a href="/wiki/Hot-water_suit" class="mw-redirect" title="Hot-water suit">Hot-water suit</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Helmets<br />and masks</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Anti-fog" title="Anti-fog">Anti-fog</a></li> <li><a href="/wiki/Diving_helmet" title="Diving helmet">Diving helmet</a> <ul><li><a href="/wiki/Free-flow_helmet" class="mw-redirect" title="Free-flow helmet">Free-flow helmet</a></li> <li><a href="/wiki/Lightweight_demand_helmet" class="mw-redirect" title="Lightweight demand helmet">Lightweight demand helmet</a></li> <li><a href="/wiki/Orinasal_mask" title="Orinasal mask">Orinasal mask</a></li> <li><a href="/wiki/Reclaim_helmet" class="mw-redirect" title="Reclaim helmet">Reclaim helmet</a></li> <li><a href="/wiki/Shallow_water_helmet" class="mw-redirect" title="Shallow water helmet">Shallow water helmet</a></li> <li><a href="/wiki/Standard_diving_helmet" class="mw-redirect" title="Standard diving helmet">Standard diving helmet</a></li></ul></li> <li><a href="/wiki/Diving_mask" title="Diving mask">Diving mask</a> <ul><li><a href="/wiki/Band_mask" class="mw-redirect" title="Band mask">Band mask</a></li> <li><a href="/wiki/Full-face_mask" class="mw-redirect" title="Full-face mask">Full-face mask</a></li> <li><a href="/wiki/Half_mask" class="mw-redirect" title="Half mask">Half mask</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Instrumentation</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Bottom_timer" class="mw-redirect" title="Bottom timer">Bottom timer</a></li> <li><a href="/wiki/Depth_gauge" title="Depth gauge">Depth gauge</a></li> <li><a href="/wiki/Dive_computer" title="Dive computer">Dive computer</a></li> <li><a href="/wiki/Dive_timer" class="mw-redirect" title="Dive timer">Dive timer</a></li> <li><a href="/wiki/Diving_watch" title="Diving watch">Diving watch</a> <ul><li><a href="/wiki/Helium_release_valve" title="Helium release valve">Helium release valve</a></li></ul></li> <li><a href="/wiki/Electro-galvanic_oxygen_sensor" title="Electro-galvanic oxygen sensor">Electro-galvanic oxygen sensor</a></li> <li><a href="/wiki/Pneumofathometer" class="mw-redirect" title="Pneumofathometer">Pneumofathometer</a></li> <li><a href="/wiki/Submersible_pressure_gauge" class="mw-redirect" title="Submersible pressure gauge">Submersible pressure gauge</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Mobility<br />equipment</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Diver_propulsion_vehicle" title="Diver propulsion vehicle">Diver propulsion vehicle</a></li> <li><a href="/wiki/Diving_bell" title="Diving bell">Diving bell</a> <ul><li><a href="/wiki/Closed_bell" class="mw-redirect" title="Closed bell">Closed bell</a></li> <li><a href="/wiki/Wet_bell" class="mw-redirect" title="Wet bell">Wet bell</a></li></ul></li> <li><a href="/wiki/Diving_stage" class="mw-redirect" title="Diving stage">Diving stage</a></li> <li><a href="/wiki/Swimfin" title="Swimfin">Swimfin</a> <ul><li><a href="/wiki/Monofin" title="Monofin">Monofin</a></li> <li><a href="/wiki/PowerSwim" title="PowerSwim">PowerSwim</a></li></ul></li> <li><a href="/wiki/Towboard" title="Towboard">Towboard</a></li> <li><a href="/wiki/Wet_sub" title="Wet sub">Wet sub</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Safety<br />equipment</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Alternative_air_source" title="Alternative air source">Alternative air source</a> <ul><li><a href="/wiki/Octopus_regulator" class="mw-redirect" title="Octopus regulator">Octopus regulator</a></li> <li><a href="/wiki/Pony_bottle" title="Pony bottle">Pony bottle</a></li></ul></li> <li><a href="/wiki/Bolt_snap" title="Bolt snap">Bolt snap</a></li> <li><a href="/wiki/Buddy_line" class="mw-redirect" title="Buddy line">Buddy line</a></li> <li><a href="/wiki/Dive_light" title="Dive light">Dive light</a></li> <li><a href="/wiki/Diver%27s_cutting_tool" class="mw-redirect" title="Diver's cutting tool">Diver's cutting tool</a> <ul><li><a href="/wiki/Diver%27s_knife" class="mw-redirect" title="Diver's knife">Diver's knife</a></li></ul></li> <li><a href="/wiki/Diver%27s_telephone" class="mw-redirect" title="Diver's telephone">Diver's telephone</a></li> <li><a href="/wiki/Through-water_communications" class="mw-redirect" title="Through-water communications">Through-water communications</a> <ul><li><a href="/wiki/Underwater_acoustic_communication" title="Underwater acoustic communication">Underwater acoustic communication</a></li></ul></li> <li><a href="/wiki/Diving_bell" title="Diving bell">Diving bell</a></li> <li><a href="/wiki/Diving_safety_harness" class="mw-redirect" title="Diving safety harness">Diving safety harness</a></li> <li><a href="/wiki/Emergency_gas_supply" class="mw-redirect" title="Emergency gas supply">Emergency gas supply</a> <ul><li><a href="/wiki/Bailout_block" class="mw-redirect" title="Bailout block">Bailout block</a></li> <li><a href="/wiki/Bailout_bottle" title="Bailout bottle">Bailout bottle</a></li></ul></li> <li><a href="/wiki/Lifeline_(diving)" class="mw-redirect" title="Lifeline (diving)">Lifeline</a> <ul><li><a href="/wiki/Screw_gate_carabiner" class="mw-redirect" title="Screw gate carabiner">Screw gate carabiner</a></li></ul></li> <li><a href="/wiki/Emergency_locator_beacon" title="Emergency locator beacon">Emergency locator beacon</a></li> <li><a href="/wiki/Rescue_tether" class="mw-redirect" title="Rescue tether">Rescue tether</a></li> <li><a href="/wiki/Safety_helmet" class="mw-redirect" title="Safety helmet">Safety helmet</a></li> <li><a href="/wiki/Shark-proof_cage" class="mw-redirect" title="Shark-proof cage">Shark-proof cage</a></li> <li><a href="/wiki/Snoopy_loop" class="mw-redirect" title="Snoopy loop">Snoopy loop</a></li> <li>Navigation equipment <ul><li><a href="/wiki/Distance_line" title="Distance line">Distance line</a></li> <li><a href="/wiki/Diving_compass" class="mw-redirect" title="Diving compass">Diving compass</a></li> <li><a href="/wiki/Dive_reel" class="mw-redirect" title="Dive reel">Dive reel</a></li> <li><a href="/wiki/Line_marker" title="Line marker">Line marker</a></li> <li><a href="/wiki/Surface_marker_buoy" title="Surface marker buoy">Surface marker buoy</a></li> <li><a href="/wiki/Silt_screw" class="mw-redirect" title="Silt screw">Silt screw</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Underwater_breathing_apparatus" title="Underwater breathing apparatus">Underwater<br />breathing<br />apparatus</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Atmospheric_diving_suit" title="Atmospheric diving suit">Atmospheric diving suit</a></li> <li><a href="/wiki/Diving_cylinder" title="Diving cylinder">Diving cylinder</a> <ul><li><a href="/wiki/Burst_disc" class="mw-redirect" title="Burst disc">Burst disc</a></li> <li><a href="/wiki/Scuba_cylinder_valve" title="Scuba cylinder valve">Scuba cylinder valve</a></li></ul></li> <li><a href="/wiki/Diving_helmet" title="Diving helmet">Diving helmet</a> <ul><li><a href="/wiki/Reclaim_helmet" class="mw-redirect" title="Reclaim helmet">Reclaim helmet</a></li></ul></li> <li><a href="/wiki/Diving_regulator" title="Diving regulator">Diving regulator</a> <ul><li><a href="/wiki/Mechanism_of_diving_regulators" title="Mechanism of diving regulators">Mechanism of diving regulators</a></li> <li><a href="/wiki/Regulator_malfunction" class="mw-redirect" title="Regulator malfunction">Regulator malfunction</a> <ul><li><a href="/wiki/Regulator_freeze" class="mw-redirect" title="Regulator freeze">Regulator freeze</a></li></ul></li> <li><a href="/wiki/Single-hose_regulator" class="mw-redirect" title="Single-hose regulator">Single-hose regulator</a></li> <li><a href="/wiki/Twin-hose_regulator" class="mw-redirect" title="Twin-hose regulator">Twin-hose regulator</a></li></ul></li> <li><a href="/wiki/Full-face_diving_mask" title="Full-face diving mask">Full-face diving mask</a></li></ul> </div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Open-circuit_scuba" class="mw-redirect" title="Open-circuit scuba">Open-circuit<br />scuba</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Scuba_set" title="Scuba set">Scuba set</a> <ul><li><a href="/wiki/Bailout_bottle" title="Bailout bottle">Bailout bottle</a></li> <li><a href="/wiki/Decompression_cylinder" class="mw-redirect" title="Decompression cylinder">Decompression cylinder</a></li> <li><a href="/wiki/Independent_doubles" class="mw-redirect" title="Independent doubles">Independent doubles</a></li> <li><a href="/wiki/Manifolded_twin_set" class="mw-redirect" title="Manifolded twin set">Manifolded twin set</a> <ul><li><a href="/wiki/Scuba_manifold" title="Scuba manifold">Scuba manifold</a></li></ul></li> <li><a href="/wiki/Pony_bottle" title="Pony bottle">Pony bottle</a></li> <li><a href="/wiki/Scuba_configuration" class="mw-redirect" title="Scuba configuration">Scuba configuration</a></li> <li><a href="/wiki/Sidemount" class="mw-redirect" title="Sidemount">Sidemount</a></li> <li><a href="/wiki/Sling_cylinder" class="mw-redirect" title="Sling cylinder">Sling cylinder</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Diving_rebreather" title="Diving rebreather">Diving rebreathers</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Carbon_dioxide_scrubber" title="Carbon dioxide scrubber">Carbon dioxide scrubber</a></li> <li><a href="/wiki/Carleton_CDBA" class="mw-redirect" title="Carleton CDBA">Carleton CDBA</a></li> <li><a href="/wiki/Clearance_Divers_Life_Support_Equipment" title="Clearance Divers Life Support Equipment">Clearance Divers Life Support Equipment</a></li> <li><a href="/wiki/Cryogenic_rebreather" class="mw-redirect" title="Cryogenic rebreather">Cryogenic rebreather</a></li> <li><a href="/wiki/CUMA" title="CUMA">CUMA</a></li> <li><a href="/wiki/DSEA" class="mw-redirect" title="DSEA">DSEA</a></li> <li><a href="/wiki/Dr%C3%A4ger_Dolphin" class="mw-redirect" title="Dräger Dolphin">Dolphin</a></li> <li><a href="/wiki/Halcyon_PVR-BASC" title="Halcyon PVR-BASC">Halcyon PVR-BASC</a></li> <li><a href="/wiki/Halcyon_RB80" title="Halcyon RB80">Halcyon RB80</a></li> <li><a href="/wiki/IDA71" title="IDA71">IDA71</a></li> <li><a href="/wiki/Interspiro_DCSC" title="Interspiro DCSC">Interspiro DCSC</a></li> <li><a href="/wiki/LAR-5" class="mw-redirect" title="LAR-5">LAR-5</a></li> <li><a href="/wiki/LAR-6" class="mw-redirect" title="LAR-6">LAR-6</a></li> <li><a href="/wiki/LAR-V" class="mw-redirect" title="LAR-V">LAR-V</a></li> <li><a href="/wiki/Lambertsen_Amphibious_Respiratory_Unit" title="Lambertsen Amphibious Respiratory Unit">LARU</a></li> <li><a href="/wiki/Mark_IV_Amphibian" title="Mark IV Amphibian">Mark IV Amphibian</a></li> <li><a href="/wiki/Porpoise_(scuba_gear)" title="Porpoise (scuba gear)">Porpoise</a></li> <li><a href="/wiki/Dr%C3%A4ger_Ray" class="mw-redirect" title="Dräger Ray">Ray</a></li> <li><a href="/wiki/Siebe_Gorman_CDBA" title="Siebe Gorman CDBA">Siebe Gorman CDBA</a></li> <li><a href="/wiki/Siebe_Gorman_Salvus" title="Siebe Gorman Salvus">Salvus</a></li> <li><a href="/wiki/Siva_(rebreather)" class="mw-redirect" title="Siva (rebreather)">Siva</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Surface-supplied_diving_equipment" title="Surface-supplied diving equipment">Surface-supplied<br />diving equipment</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Air_line" title="Air line">Air line</a></li> <li><a href="/wiki/Diver%27s_umbilical" class="mw-redirect" title="Diver's umbilical">Diver's umbilical</a></li> <li><a href="/wiki/Diving_air_compressor" title="Diving air compressor">Diving air compressor</a></li> <li><a href="/wiki/Gas_panel" class="mw-redirect" title="Gas panel">Gas panel</a></li> <li><a href="/wiki/Hookah_(diving)" class="mw-redirect" title="Hookah (diving)">Hookah</a></li> <li><a href="/wiki/Scuba_replacement" class="mw-redirect" title="Scuba replacement">Scuba replacement</a></li> <li><a href="/wiki/Snuba" title="Snuba">Snuba</a></li> <li><a href="/wiki/Standard_diving_dress" title="Standard diving dress">Standard diving dress</a></li></ul> </div></td></tr></tbody></table><div> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/List_of_diving_equipment_manufacturers" title="List of diving equipment manufacturers"> Diving<br />equipment<br />manufacturers</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/AP_Diving" title="AP Diving">AP Diving</a></li> <li><a href="/wiki/Apeks" title="Apeks">Apeks</a></li> <li><a href="/wiki/Aqua_Lung_America" title="Aqua Lung America">Aqua Lung America</a></li> <li><a href="/wiki/Aqua_Lung/La_Spirotechnique" title="Aqua Lung/La Spirotechnique">Aqua Lung/La Spirotechnique</a></li> <li><a href="/wiki/Beuchat" title="Beuchat">Beuchat</a></li> <li><a href="/wiki/Ren%C3%A9_Cavalero" title="René Cavalero">René Cavalero</a></li> <li><a href="/wiki/Cis-Lunar" title="Cis-Lunar">Cis-Lunar</a></li> <li><a href="/wiki/Cressi-Sub" title="Cressi-Sub">Cressi-Sub</a></li> <li><a href="/wiki/Dacor_(scuba_diving)" title="Dacor (scuba diving)">Dacor</a></li> <li><a href="/wiki/DESCO" title="DESCO">DESCO</a></li> <li><a href="/wiki/Dive_Xtras" title="Dive Xtras">Dive Xtras</a></li> <li><a href="/wiki/Divex" title="Divex">Divex</a></li> <li><a href="/wiki/Diving_Unlimited_International" title="Diving Unlimited International">Diving Unlimited International</a></li> <li><a href="/wiki/Dr%C3%A4gerwerk" class="mw-redirect" title="Drägerwerk">Drägerwerk</a></li> <li><a href="/wiki/Faber_Industrie_S.p.A." title="Faber Industrie S.p.A.">Faber</a></li> <li><a href="/wiki/Fenzy" title="Fenzy">Fenzy</a></li> <li><a href="/wiki/Maurice_Fernez" title="Maurice Fernez">Maurice Fernez</a></li> <li><a href="/wiki/Luigi_Ferraro_(naval_officer)" class="mw-redirect" title="Luigi Ferraro (naval officer)">Technisub</a></li> <li><a href="/wiki/Oscar_Gugen" title="Oscar Gugen">Oscar Gugen</a></li> <li><a href="/wiki/Heinke_(diving_equipment_manufacturer)" title="Heinke (diving equipment manufacturer)">Heinke</a></li> <li><a href="/wiki/HeinrichsWeikamp" title="HeinrichsWeikamp">HeinrichsWeikamp</a></li> <li><a href="/wiki/Johnson_Outdoors" title="Johnson Outdoors">Johnson Outdoors</a></li> <li><a href="/wiki/Mares_(scuba_equipment)" title="Mares (scuba equipment)">Mares</a></li> <li><a href="/wiki/Morse_Diving" title="Morse Diving">Morse Diving</a></li> <li><a href="/wiki/Nemrod" title="Nemrod">Nemrod</a></li> <li><a href="/wiki/Oceanic_Worldwide" title="Oceanic Worldwide">Oceanic Worldwide</a></li> <li><a href="/wiki/Porpoise_(scuba_gear)" title="Porpoise (scuba gear)">Porpoise</a></li> <li><a href="/wiki/Shearwater_Research" title="Shearwater Research">Shearwater Research</a></li> <li><a href="/wiki/Siebe_Gorman" title="Siebe Gorman">Siebe Gorman</a></li> <li><a href="/wiki/Submarine_Products" title="Submarine Products">Submarine Products</a></li> <li><a href="/wiki/Suunto" title="Suunto">Suunto</a></li></ul> </div></td></tr></tbody></table><div> </div></td></tr></tbody></table><div></div></td></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks mw-collapsible mw-collapsed navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><div id="Diving_support_equipment" style="font-size:114%;margin:0 4em"><a href="/wiki/Diving_support_equipment" title="Diving support equipment">Diving support equipment</a></div></th></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">Access equipment</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Boarding_stirrup" class="mw-redirect" title="Boarding stirrup">Boarding stirrup</a></li> <li><a href="/wiki/Diver_lift" class="mw-redirect" title="Diver lift">Diver lift</a></li> <li><a href="/wiki/Diving_bell" title="Diving bell">Diving bell</a></li> <li><a href="/wiki/Diving_ladder" class="mw-redirect" title="Diving ladder">Diving ladder</a></li> <li><a href="/wiki/Diving_platform_(scuba)" class="mw-redirect" title="Diving platform (scuba)">Diving platform (scuba)</a></li> <li><a href="/wiki/Diving_stage" class="mw-redirect" title="Diving stage">Diving stage</a></li> <li><a href="/wiki/Downline_(diving)" title="Downline (diving)">Downline</a></li> <li><a href="/wiki/Jackstay" title="Jackstay">Jackstay</a></li> <li><a href="/wiki/Launch_and_recovery_system_(diving)" class="mw-redirect" title="Launch and recovery system (diving)">Launch and recovery system</a></li> <li><a href="/wiki/Messenger_line" title="Messenger line">Messenger line</a></li> <li><a href="/wiki/Moon_pool" title="Moon pool">Moon pool</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Breathing gas<br />handling</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Diving_air_compressor#Filtration" title="Diving air compressor">Air filtration</a> <ul><li><a href="/wiki/Activated_carbon" title="Activated carbon">Activated carbon</a></li> <li><a href="/wiki/Hopcalite" title="Hopcalite">Hopcalite</a></li> <li><a href="/wiki/Molecular_sieve" title="Molecular sieve">Molecular sieve</a></li> <li><a href="/wiki/Silica_gel" title="Silica gel">Silica gel</a></li></ul></li> <li><a href="/wiki/Booster_pump" title="Booster pump">Booster pump</a></li> <li><a href="/wiki/Carbon_dioxide_scrubber" title="Carbon dioxide scrubber">Carbon dioxide scrubber</a></li> <li><a href="/wiki/Cascade_filling_system" title="Cascade filling system">Cascade filling system</a></li> <li><a href="/wiki/Diver%27s_pump" title="Diver's pump">Diver's pump</a></li> <li><a href="/wiki/Diving_air_compressor" title="Diving air compressor">Diving air compressor</a> <ul><li><a href="/wiki/Diving_air_filter" class="mw-redirect" title="Diving air filter">Diving air filter</a></li> <li><a href="/wiki/Water_separator" class="mw-redirect" title="Water separator">Water separator</a></li> <li><a href="/wiki/High_pressure_breathing_air_compressor" class="mw-redirect" title="High pressure breathing air compressor">High pressure breathing air compressor</a></li> <li><a href="/wiki/Low_pressure_breathing_air_compressor" class="mw-redirect" title="Low pressure breathing air compressor">Low pressure breathing air compressor</a></li></ul></li> <li><a href="/wiki/Gas_blending" title="Gas blending">Gas blending</a> <ul><li><a href="/wiki/Gas_blending_for_scuba_diving" title="Gas blending for scuba diving">Gas blending for scuba diving</a></li></ul></li> <li><a href="/wiki/Gas_panel" class="mw-redirect" title="Gas panel">Gas panel</a></li> <li><a href="/wiki/Gas_reclaim_system" class="mw-redirect" title="Gas reclaim system">Gas reclaim system</a></li> <li><a href="/wiki/Gas_storage_bank" class="mw-redirect" title="Gas storage bank">Gas storage bank</a> <ul><li><a href="/wiki/Gas_storage_quad" class="mw-redirect" title="Gas storage quad">Gas storage quad</a></li> <li><a href="/wiki/Gas_storage_tube" class="mw-redirect" title="Gas storage tube">Gas storage tube</a></li></ul></li> <li><a href="/wiki/Helium_analyzer" title="Helium analyzer">Helium analyzer</a></li> <li><a href="/wiki/Nitrox_production" class="mw-redirect" title="Nitrox production">Nitrox production</a> <ul><li><a href="/wiki/Membrane_gas_separation" title="Membrane gas separation">Membrane gas separation</a></li> <li><a href="/wiki/Pressure_swing_adsorption" title="Pressure swing adsorption">Pressure swing adsorption</a></li></ul></li> <li><a href="/wiki/Oxygen_analyser" class="mw-redirect" title="Oxygen analyser">Oxygen analyser</a> <ul><li><a href="/wiki/Electro-galvanic_oxygen_sensor" title="Electro-galvanic oxygen sensor">Electro-galvanic oxygen sensor</a></li></ul></li> <li><a href="/wiki/Oxygen_compatibility" title="Oxygen compatibility">Oxygen compatibility</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Decompression_equipment" title="Decompression equipment">Decompression<br />equipment</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Air-lock" class="mw-redirect" title="Air-lock">Air-lock</a></li> <li><a href="/wiki/Built-in_breathing_system" title="Built-in breathing system">Built-in breathing system</a></li> <li><a href="/wiki/Decompression_tables" class="mw-redirect" title="Decompression tables">Decompression tables</a></li> <li><a href="/wiki/Diving_bell" title="Diving bell">Diving bell</a> <ul><li><a href="/wiki/Bell_cursor" class="mw-redirect" title="Bell cursor">Bell cursor</a></li> <li><a href="/wiki/Closed_bell" class="mw-redirect" title="Closed bell">Closed bell</a></li> <li><a href="/wiki/Clump_weight" class="mw-redirect" title="Clump weight">Clump weight</a></li> <li><a href="/wiki/Launch_and_recovery_system_(diving)" class="mw-redirect" title="Launch and recovery system (diving)">Launch and recovery system</a></li> <li><a href="/wiki/Wet_bell" class="mw-redirect" title="Wet bell">Wet bell</a></li></ul></li> <li><a href="/wiki/Diving_chamber" title="Diving chamber">Diving chamber</a></li> <li><a href="/wiki/Diving_stage" class="mw-redirect" title="Diving stage">Diving stage</a></li> <li><a href="/wiki/Recreational_Dive_Planner" title="Recreational Dive Planner">Recreational Dive Planner</a></li> <li><a href="/wiki/Saturation_system" class="mw-redirect" title="Saturation system">Saturation system</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Platforms</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Dive_boat" title="Dive boat">Dive boat</a> <ul><li><a href="/wiki/Canoe_and_kayak_diving" title="Canoe and kayak diving">Canoe and kayak diving</a></li> <li><a href="/wiki/Combat_rubber_raiding_craft" title="Combat rubber raiding craft">Combat rubber raiding craft</a></li> <li><a href="/wiki/Liveaboard" title="Liveaboard">Liveaboard</a></li> <li><a href="/wiki/Subskimmer" title="Subskimmer">Subskimmer</a></li></ul></li> <li><a href="/wiki/Diving_support_vessel" title="Diving support vessel">Diving support vessel</a> <ul><li><a href="/wiki/HMS_Challenger_(K07)" title="HMS Challenger (K07)">HMS Challenger (K07)</a></li></ul></li></ul> </div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="Underwaterhabitat" scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Underwater_habitat" title="Underwater habitat">Underwater<br />habitat</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Aquarius_Reef_Base" title="Aquarius Reef Base">Aquarius Reef Base</a></li> <li><a href="/wiki/Continental_Shelf_Station_Two" title="Continental Shelf Station Two">Continental Shelf Station Two</a></li> <li><a href="/wiki/Helgoland_Habitat" title="Helgoland Habitat">Helgoland Habitat</a></li> <li><a href="/wiki/Scott_Carpenter_Space_Analog_Station" title="Scott Carpenter Space Analog Station">Scott Carpenter Space Analog Station</a></li> <li><a href="/wiki/SEALAB" title="SEALAB">SEALAB</a></li> <li><a href="/wiki/Tektite_habitat" title="Tektite habitat">Tektite habitat</a></li></ul> </div></td></tr></tbody></table><div> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Remotely_operated_underwater_vehicle" title="Remotely operated underwater vehicle">Remotely operated<br />underwater vehicles</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/8A4-class_ROUV" title="8A4-class ROUV">8A4-class ROUV</a></li> <li><a href="/wiki/ABISMO" title="ABISMO">ABISMO</a></li> <li><a href="/wiki/Atlantis_ROV_Team" title="Atlantis ROV Team">Atlantis ROV Team</a></li> <li><a href="/wiki/COTSBot" title="COTSBot">COTSBot</a></li> <li><a href="/wiki/CURV" title="CURV">CURV</a></li> <li><a href="/wiki/Deep_Drone" title="Deep Drone">Deep Drone</a></li> <li><a href="/wiki/%C3%89paulard" title="Épaulard">Épaulard</a></li> <li><a href="/wiki/Global_Explorer_ROV" title="Global Explorer ROV">Global Explorer ROV</a></li> <li><a href="/wiki/Goldfish-class_ROUV" title="Goldfish-class ROUV">Goldfish-class ROUV</a></li> <li><a href="/wiki/Kaik%C5%8D_ROV" title="Kaikō ROV">Kaikō ROV</a></li> <li><a href="/wiki/Ka%C5%9Fif_ROUV" title="Kaşif ROUV">Kaşif ROUV</a></li> <li><a href="/wiki/Long-Term_Mine_Reconnaissance_System" title="Long-Term Mine Reconnaissance System">Long-Term Mine Reconnaissance System</a></li> <li><a href="/wiki/Mini_Rover_ROV" title="Mini Rover ROV">Mini Rover ROV</a></li> <li><a href="/wiki/OpenROV" title="OpenROV">OpenROV</a></li> <li><a href="/wiki/ROV_KIEL_6000" title="ROV KIEL 6000">ROV KIEL 6000</a></li> <li><a href="/wiki/ROV_PHOCA" title="ROV PHOCA">ROV PHOCA</a></li> <li><a href="/wiki/Scorpio_ROV" title="Scorpio ROV">Scorpio ROV</a></li> <li><a href="/wiki/Sea_Dragon-class_ROV" title="Sea Dragon-class ROV">Sea Dragon-class ROV</a></li> <li><a href="/wiki/Seabed_tractor" title="Seabed tractor">Seabed tractor</a></li> <li><a href="/wiki/Seafox_drone" title="Seafox drone">Seafox drone</a></li> <li><a href="/wiki/SeaPerch" title="SeaPerch">SeaPerch</a></li> <li><a href="/wiki/SJT-class_ROUV" title="SJT-class ROUV">SJT-class ROUV</a></li> <li><a href="/wiki/T1200_Trenching_Unit" title="T1200 Trenching Unit">T1200 Trenching Unit</a></li> <li><a href="/wiki/VideoRay_UROVs" title="VideoRay UROVs">VideoRay UROVs</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Safety equipment</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Diver_down_flag" title="Diver down flag">Diver down flag</a></li> <li><a href="/wiki/Diving_shot" title="Diving shot">Diving shot</a></li> <li><a href="/wiki/ENOS_Rescue-System" title="ENOS Rescue-System">ENOS Rescue-System</a></li> <li><a href="/wiki/Hyperbaric_lifeboat" class="mw-redirect" title="Hyperbaric lifeboat">Hyperbaric lifeboat</a></li> <li><a href="/wiki/Hyperbaric_stretcher" title="Hyperbaric stretcher">Hyperbaric stretcher</a></li> <li><a href="/wiki/Jackstay_(diving)" class="mw-redirect" title="Jackstay (diving)">Jackstay</a></li> <li><a href="/wiki/Jonline" class="mw-redirect" title="Jonline">Jonline</a></li> <li><a href="/wiki/Reserve_gas_supply_(diving)" class="mw-redirect" title="Reserve gas supply (diving)">Reserve gas supply</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">General</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Diving_spread" class="mw-redirect" title="Diving spread">Diving spread</a> <ul><li><a href="/wiki/Air_spread" class="mw-redirect" title="Air spread">Air spread</a></li> <li><a href="/wiki/Saturation_spread" class="mw-redirect" title="Saturation spread">Saturation spread</a></li></ul></li> <li><a href="/wiki/Hot_water_system_(diving)" class="mw-redirect" title="Hot water system (diving)">Hot water system</a></li> <li><a href="/wiki/Sonar" title="Sonar">Sonar</a> <ul><li><a href="/wiki/Underwater_acoustic_positioning_system" title="Underwater acoustic positioning system">Underwater acoustic positioning system</a></li> <li><a href="/wiki/Underwater_acoustic_communication" title="Underwater acoustic communication">Underwater acoustic communication</a></li></ul></li></ul> </div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks mw-collapsible mw-collapsed navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><div id="Freediving" style="font-size:114%;margin:0 4em"><a href="/wiki/Freediving" title="Freediving">Freediving</a></div></th></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">Activities</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Aquathlon_(underwater_wrestling)" title="Aquathlon (underwater wrestling)">Aquathlon</a></li> <li><a href="/wiki/Apnoea_finswimming" class="mw-redirect" title="Apnoea finswimming">Apnoea finswimming</a></li> <li><a href="/wiki/Freediving" title="Freediving">Freediving</a></li> <li><a href="/wiki/Haenyeo" title="Haenyeo">Haenyeo</a></li> <li><a href="/wiki/Pearl_hunting" title="Pearl hunting">Pearl hunting</a> <ul><li><a href="/wiki/Ama_(diving)" title="Ama (diving)">Ama</a></li></ul></li> <li><a href="/wiki/Snorkeling" title="Snorkeling">Snorkeling</a></li> <li><a href="/wiki/Spearfishing" title="Spearfishing">Spearfishing</a></li> <li><a href="/wiki/Underwater_football" title="Underwater football">Underwater football</a></li> <li><a href="/wiki/Underwater_hockey" title="Underwater hockey">Underwater hockey</a></li> <li><a href="/wiki/Underwater_rugby" title="Underwater rugby">Underwater rugby</a></li> <li><a href="/wiki/Underwater_target_shooting" title="Underwater target shooting">Underwater target shooting</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Competitions</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Nordic_Deep" title="Nordic Deep">Nordic Deep</a></li> <li><a href="/wiki/Vertical_Blue" title="Vertical Blue">Vertical Blue</a></li> <li>Disciplines <ul><li><a href="/wiki/Constant_weight" class="mw-redirect" title="Constant weight">Constant weight</a> (CWT)</li> <li><a href="/wiki/Constant_weight_bi-fins" title="Constant weight bi-fins">Constant weight bi-fins</a> (CWTB)</li> <li><a href="/wiki/Constant_weight_without_fins" title="Constant weight without fins">Constant weight without fins</a> (CNF)</li> <li><a href="/wiki/Dynamic_apnea" title="Dynamic apnea">Dynamic apnea</a> (DYN)</li> <li><a href="/wiki/Dynamic_apnea_without_fins" class="mw-redirect" title="Dynamic apnea without fins">Dynamic apnea without fins</a> (DNF)</li> <li><a href="/wiki/Free_immersion" class="mw-redirect" title="Free immersion">Free immersion</a> (FIM)</li> <li><a href="/wiki/No-limits_apnea" title="No-limits apnea">No-limits apnea</a> (NLT)</li> <li><a href="/wiki/Static_apnea" title="Static apnea">Static apnea</a> (STA)</li> <li><a href="/wiki/Skandalopetra_diving" title="Skandalopetra diving">Skandalopetra diving</a></li> <li><a href="/wiki/Variable_weight_apnea" class="mw-redirect" title="Variable weight apnea">Variable weight apnea</a> (VWT)</li> <li><a href="/wiki/Variable_weight_apnea_without_fins" class="mw-redirect" title="Variable weight apnea without fins">Variable weight apnea without fins</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Equipment</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Diving_mask" title="Diving mask">Diving mask</a></li> <li><a href="/wiki/Diving_suit" title="Diving suit">Diving suit</a></li> <li><a href="/wiki/Hawaiian_sling" title="Hawaiian sling">Hawaiian sling</a></li> <li><a href="/wiki/Polespear" title="Polespear">Polespear</a></li> <li><a href="/wiki/Snorkel_(swimming)" title="Snorkel (swimming)">Snorkel (swimming)</a></li> <li><a href="/wiki/Speargun" title="Speargun">Speargun</a></li> <li><a href="/wiki/Swimfin" title="Swimfin">Swimfins</a> <ul><li><a href="/wiki/Monofin" title="Monofin">Monofin</a></li></ul></li> <li><a href="/wiki/Water_polo_cap" title="Water polo cap">Water polo cap</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Freedivers</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Deborah_Andollo" title="Deborah Andollo">Deborah Andollo</a></li> <li><a href="/wiki/Simone_Arrigoni" title="Simone Arrigoni">Simone Arrigoni</a></li> <li><a href="/wiki/Peppo_Biscarini" title="Peppo Biscarini">Peppo Biscarini</a></li> <li><a href="/wiki/Michael_Board" title="Michael Board">Michael Board</a></li> <li><a href="/wiki/Sara_Campbell" title="Sara Campbell">Sara Campbell</a></li> <li><a href="/wiki/Derya_Can_G%C3%B6%C3%A7en" class="mw-redirect" title="Derya Can Göçen">Derya Can Göçen</a></li> <li><a href="/wiki/Goran_%C4%8Colak" title="Goran Čolak">Goran Čolak</a></li> <li><a href="/wiki/Carlos_Coste" title="Carlos Coste">Carlos Coste</a></li> <li><a href="/wiki/Robert_Croft_(diver)" title="Robert Croft (diver)">Robert Croft</a></li> <li><a href="/wiki/Mandy-Rae_Cruickshank" title="Mandy-Rae Cruickshank">Mandy-Rae Cruickshank</a></li> <li><a href="/wiki/Yasemin_Dalk%C4%B1l%C4%B1%C3%A7" title="Yasemin Dalkılıç">Yasemin Dalkılıç</a></li> <li><a href="/wiki/Leonardo_D%27Imporzano" title="Leonardo D'Imporzano">Leonardo D'Imporzano</a></li> <li><a href="/wiki/Flavia_Eberhard" title="Flavia Eberhard">Flavia Eberhard</a></li> <li><a href="/wiki/%C5%9Eahika_Erc%C3%BCmen" title="Şahika Ercümen">Şahika Ercümen</a></li> <li><a href="/wiki/Emma_Farrell_(freediver)" title="Emma Farrell (freediver)">Emma Farrell</a></li> <li><a href="/wiki/Francisco_Ferreras" title="Francisco Ferreras">Francisco Ferreras</a></li> <li><a href="/wiki/Pierre_Frolla" title="Pierre Frolla">Pierre Frolla</a></li> <li><a href="/wiki/Flavia_Eberhard" title="Flavia Eberhard">Flavia Eberhard</a></li> <li><a href="/wiki/Mehgan_Heaney-Grier" title="Mehgan Heaney-Grier">Mehgan Heaney-Grier</a></li> <li><a href="/wiki/Elisabeth_Kristoffersen" title="Elisabeth Kristoffersen">Elisabeth Kristoffersen</a></li> <li><a href="/wiki/Andriy_Yevhenovych_Khvetkevych" class="mw-redirect" title="Andriy Yevhenovych Khvetkevych">Andriy Yevhenovych Khvetkevych</a></li> <li><a href="/wiki/Lo%C3%AFc_Leferme" title="Loïc Leferme">Loïc Leferme</a></li> <li><a href="/wiki/Enzo_Maiorca" title="Enzo Maiorca">Enzo Maiorca</a></li> <li><a href="/wiki/Jacques_Mayol" title="Jacques Mayol">Jacques Mayol</a></li> <li><a href="/wiki/Audrey_Mestre" title="Audrey Mestre">Audrey Mestre</a></li> <li><a href="/wiki/Karol_Meyer" title="Karol Meyer">Karol Meyer</a></li> <li><a href="/wiki/Kate_Middleton_(free-diver)" title="Kate Middleton (free-diver)">Kate Middleton</a></li> <li><a href="/wiki/St%C3%A9phane_Mifsud" title="Stéphane Mifsud">Stéphane Mifsud</a></li> <li><a href="/wiki/Alexey_Molchanov" title="Alexey Molchanov">Alexey Molchanov</a></li> <li><a href="/wiki/Natalia_Molchanova" title="Natalia Molchanova">Natalia Molchanova</a></li> <li><a href="/wiki/Dave_Mullins_(freediver)" title="Dave Mullins (freediver)">Dave Mullins</a></li> <li><a href="/wiki/Patrick_Musimu" title="Patrick Musimu">Patrick Musimu</a></li> <li><a href="/wiki/Guillaume_N%C3%A9ry" title="Guillaume Néry">Guillaume Néry</a></li> <li><a href="/wiki/Herbert_Nitsch" title="Herbert Nitsch">Herbert Nitsch</a></li> <li><a href="/wiki/Umberto_Pelizzari" title="Umberto Pelizzari">Umberto Pelizzari</a></li> <li><a href="/wiki/Liv_Philip" title="Liv Philip">Liv Philip</a></li> <li><a href="/wiki/Annelie_Pompe" title="Annelie Pompe">Annelie Pompe</a></li> <li><a href="/wiki/Stig_Severinsen" title="Stig Severinsen">Stig Severinsen</a></li> <li><a href="/wiki/Tom_Sietas" title="Tom Sietas">Tom Sietas</a></li> <li><a href="/wiki/Aharon_Solomons" title="Aharon Solomons">Aharon Solomons</a></li> <li><a href="/wiki/Martin_%C5%A0t%C4%9Bp%C3%A1nek_(free-diver)" class="mw-redirect" title="Martin Štěpánek (free-diver)">Martin Štěpánek</a></li> <li><a href="/wiki/Walter_Steyn" title="Walter Steyn">Walter Steyn</a></li> <li><a href="/wiki/Tanya_Streeter" title="Tanya Streeter">Tanya Streeter</a></li> <li><a href="/wiki/William_Trubridge" title="William Trubridge">William Trubridge</a></li> <li><a href="/wiki/Devrim_Cenk_Ulusoy" title="Devrim Cenk Ulusoy">Devrim Cenk Ulusoy</a></li> <li><a href="/wiki/Fatma_Uruk" title="Fatma Uruk">Fatma Uruk</a></li> <li><a href="/wiki/Danai_Varveri" title="Danai Varveri">Danai Varveri</a></li> <li><a href="/wiki/Alessia_Zecchini" title="Alessia Zecchini">Alessia Zecchini</a></li> <li><a href="/wiki/Nataliia_Zharkova" title="Nataliia Zharkova">Nataliia Zharkova</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Hazards</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Barotrauma" title="Barotrauma">Barotrauma</a></li> <li><a href="/wiki/Drowning" title="Drowning">Drowning</a></li> <li><a href="/wiki/Freediving_blackout" title="Freediving blackout">Freediving blackout</a> <ul><li><a href="/wiki/Deep-water_blackout" class="mw-redirect" title="Deep-water blackout">Deep-water blackout</a></li> <li><a href="/wiki/Freediving_blackout#Terminology" title="Freediving blackout">Shallow-water blackout</a></li></ul></li> <li><a href="/wiki/Hypercapnia" title="Hypercapnia">Hypercapnia</a></li> <li><a href="/wiki/Hypothermia" title="Hypothermia">Hypothermia</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Historical</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Ama_(diving)" title="Ama (diving)">Ama</a></li> <li><a href="/wiki/Octopus_wrestling" title="Octopus wrestling">Octopus wrestling</a></li> <li><a href="/wiki/Swimming_at_the_1900_Summer_Olympics_%E2%80%93_Men%27s_underwater_swimming" title="Swimming at the 1900 Summer Olympics – Men's underwater swimming">Swimming at the 1900 Summer Olympics – Men's underwater swimming</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Organisations</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/AIDA_International" title="AIDA International">AIDA International</a></li> <li><a href="/wiki/Scuba_Schools_International" title="Scuba Schools International">Scuba Schools International</a></li> <li><a href="/wiki/Australian_Underwater_Federation" title="Australian Underwater Federation">Australian Underwater Federation</a></li> <li><a href="/wiki/British_Freediving_Association" title="British Freediving Association">British Freediving Association</a></li> <li><a href="/wiki/Conf%C3%A9d%C3%A9ration_Mondiale_des_Activit%C3%A9s_Subaquatiques" title="Confédération Mondiale des Activités Subaquatiques">Confédération Mondiale des Activités Subaquatiques</a></li> <li><a href="/wiki/F%C3%A9d%C3%A9ration_Fran%C3%A7aise_d%27%C3%89tudes_et_de_Sports_Sous-Marins" title="Fédération Française d'Études et de Sports Sous-Marins">Fédération Française d'Études et de Sports Sous-Marins</a></li> <li><a href="/wiki/Performance_Freediving_International" title="Performance Freediving International">Performance Freediving International</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks mw-collapsible mw-collapsed navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><div id="Professional_diving" style="font-size:114%;margin:0 4em"><a href="/wiki/Professional_diving" title="Professional diving">Professional diving</a></div></th></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">Occupations</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Ama_(diving)" title="Ama (diving)">Ama</a></li> <li><a href="/wiki/Commercial_diver" class="mw-redirect" title="Commercial diver">Commercial diver</a> <ul><li><a href="/wiki/Commercial_offshore_diver" class="mw-redirect" title="Commercial offshore diver">Commercial offshore diver</a></li> <li><a href="/wiki/Hazmat_diver" class="mw-redirect" title="Hazmat diver">Hazmat diver</a></li></ul></li> <li><a href="/wiki/Divemaster" title="Divemaster">Divemaster</a></li> <li><a href="/wiki/Diving_instructor" title="Diving instructor">Diving instructor</a></li> <li><a href="/wiki/Diving_safety_officer" title="Diving safety officer">Diving safety officer</a></li> <li><a href="/wiki/Diving_superintendent" class="mw-redirect" title="Diving superintendent">Diving superintendent</a></li> <li><a href="/wiki/Diving_supervisor" title="Diving supervisor">Diving supervisor</a></li> <li><a href="/wiki/Haenyeo" title="Haenyeo">Haenyeo</a></li> <li><a href="/wiki/Media_diver" class="mw-redirect" title="Media diver">Media diver</a></li> <li><a href="/wiki/Police_diver" class="mw-redirect" title="Police diver">Police diver</a></li> <li><a href="/wiki/Public_safety_diver" class="mw-redirect" title="Public safety diver">Public safety diver</a></li> <li><a href="/wiki/Scientific_diver" class="mw-redirect" title="Scientific diver">Scientific diver</a></li> <li><a href="/wiki/Underwater_archaeologist" class="mw-redirect" title="Underwater archaeologist">Underwater archaeologist</a></li></ul> </div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="Militarydiving" scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Military_diving" title="Military diving">Military<br />diving</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Army_engineer_diver" title="Army engineer diver">Army engineer diver</a></li> <li><a href="/wiki/Canadian_Armed_Forces_Divers" title="Canadian Armed Forces Divers">Canadian Armed Forces Divers</a></li> <li><a href="/wiki/Clearance_diver" title="Clearance diver">Clearance diver</a></li> <li><a href="/wiki/Frogman" title="Frogman">Frogman</a></li> <li><a href="/wiki/Minentaucher" title="Minentaucher">Minentaucher</a></li> <li><a href="/wiki/Royal_Navy_ships_diver" title="Royal Navy ships diver">Royal Navy ships diver</a></li> <li><a href="/wiki/United_States_military_divers" title="United States military divers">United States military divers</a> <ul><li><a href="/wiki/Navy_diver_(United_States_Navy)" title="Navy diver (United States Navy)">U.S. Navy diver</a></li> <li><a href="/wiki/Master_diver_(United_States_Navy)" title="Master diver (United States Navy)">U.S.Navy master diver</a></li></ul></li></ul> </div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="Militarydivingunits" scope="row" class="navbox-group" style="width:1%"><a href="/wiki/List_of_military_diving_units" title="List of military diving units">Military<br />diving<br />units</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Clearance_Diving_Branch_(RAN)" title="Clearance Diving Branch (RAN)">Clearance Diving Branch (RAN)</a></li> <li><a href="/wiki/Commando_Hubert" class="mw-redirect" title="Commando Hubert">Commando Hubert</a></li> <li><a href="/wiki/Lithuanian_Special_Operations_Force" title="Lithuanian Special Operations Force">Combat Divers Service (Lithuania)</a></li> <li><a href="/wiki/Comando_Raggruppamento_Subacquei_e_Incursori_Teseo_Tesei" title="Comando Raggruppamento Subacquei e Incursori Teseo Tesei">Comando Raggruppamento Subacquei e Incursori Teseo Tesei</a></li> <li><a href="/wiki/Decima_Flottiglia_MAS" title="Decima Flottiglia MAS">Decima Flottiglia MAS</a></li> <li><a href="/wiki/Frogman_Corps_(Denmark)" title="Frogman Corps (Denmark)">Frogman Corps (Denmark)</a></li> <li><a href="/wiki/Fuerzas_Especiales" title="Fuerzas Especiales">Fuerzas Especiales</a></li> <li><a href="/wiki/Fukuryu" title="Fukuryu">Fukuryu</a></li> <li><a href="/wiki/GRUMEC" title="GRUMEC">GRUMEC</a></li> <li><a href="/wiki/Grup_Gerak_Khas" class="mw-redirect" title="Grup Gerak Khas">Grup Gerak Khas</a></li> <li><a href="/wiki/Jagdkommando" title="Jagdkommando">Jagdkommando</a></li> <li><a href="/wiki/JW_Formoza" class="mw-redirect" title="JW Formoza">JW Formoza</a></li> <li><a href="/wiki/JW_GROM" class="mw-redirect" title="JW GROM">JW GROM</a></li> <li><a href="/wiki/JW_Komandos%C3%B3w" class="mw-redirect" title="JW Komandosów">JW Komandosów</a></li> <li><a href="/wiki/Kommando_Spezialkr%C3%A4fte_Marine" title="Kommando Spezialkräfte Marine">Kommando Spezialkräfte Marine</a></li> <li><a href="/wiki/KOPASKA" title="KOPASKA">KOPASKA</a></li> <li><a href="/wiki/MARCOS" title="MARCOS">MARCOS</a></li> <li><a href="/wiki/Marine_Commandos" title="Marine Commandos">Marine Commandos</a></li> <li><a href="/wiki/Marinejegerkommandoen" title="Marinejegerkommandoen">Marinejegerkommandoen</a></li> <li><a href="/wiki/Marine_Raider_Regiment" title="Marine Raider Regiment">Marine Raider Regiment</a></li> <li><a href="/wiki/Minedykkerkommandoen" title="Minedykkerkommandoen">Minedykkerkommandoen</a></li> <li><a href="/wiki/Namibian_Marine_Corps#Operational_Diving_Unit" title="Namibian Marine Corps">Namibian Marine Corps Operational Diving Unit</a></li> <li><a href="/wiki/Naval_Diving_Unit_(Singapore)" title="Naval Diving Unit (Singapore)">Naval Diving Unit (Singapore)</a></li> <li><a href="/wiki/Naval_Service_Diving_Section" title="Naval Service Diving Section">Naval Service Diving Section</a></li> <li><a href="/wiki/Naval_Special_Operations_Command" title="Naval Special Operations Command">Naval Special Operations Command</a></li> <li><a href="/wiki/Operational_Diving_Division_(SA_Navy)" title="Operational Diving Division (SA Navy)">Operational Diving Division (SA Navy)</a></li> <li><a href="/wiki/Royal_Engineers" title="Royal Engineers">Royal Engineers</a></li> <li><a href="/wiki/Russian_commando_frogmen" title="Russian commando frogmen">Russian commando frogmen</a></li> <li><a href="/wiki/Sappers_Divers_Group" title="Sappers Divers Group">Sappers Divers Group</a></li> <li><a href="/wiki/Shayetet_13" title="Shayetet 13">Shayetet 13</a></li> <li><a href="/wiki/Special_Air_Service" title="Special Air Service">Special Air Service</a></li> <li><a href="/wiki/Special_Air_Service_Regiment" title="Special Air Service Regiment">Special Air Service Regiment</a></li> <li><a href="/wiki/Special_Actions_Detachment" title="Special Actions Detachment">Special Actions Detachment</a></li> <li><a href="/wiki/Special_Boat_Service" title="Special Boat Service">Special Boat Service</a></li> <li><a href="/wiki/Special_Boat_Squadron_(Sri_Lanka)" title="Special Boat Squadron (Sri Lanka)">Special Boat Squadron (Sri Lanka)</a></li> <li><a href="/wiki/Special_Forces_Command_(Turkey)" title="Special Forces Command (Turkey)">Special Forces Command (Turkey)</a></li> <li><a href="/wiki/Special_Forces_Group_(Belgium)" title="Special Forces Group (Belgium)">Special Forces Group (Belgium)</a></li> <li><a href="/wiki/Special_Operations_Battalion_(Croatia)" title="Special Operations Battalion (Croatia)">Special Operations Battalion (Croatia)</a></li> <li><a href="/wiki/Special_Service_Group_(Navy)" title="Special Service Group (Navy)">Special Service Group (Navy)</a></li> <li><a href="/wiki/Special_Warfare_Diving_and_Salvage" title="Special Warfare Diving and Salvage">Special Warfare Diving and Salvage</a></li> <li><a href="/wiki/Tactical_Divers_Group" title="Tactical Divers Group">Tactical Divers Group</a></li> <li><a href="/wiki/United_States_Marine_Corps_Force_Reconnaissance" title="United States Marine Corps Force Reconnaissance">US Marine Corps Force Reconnaissance</a></li> <li><a href="/wiki/United_States_Marine_Corps_Reconnaissance_Battalions" title="United States Marine Corps Reconnaissance Battalions">US Marine Corps Reconnaissance Battalions</a></li> <li><a href="/wiki/United_States_Navy_SEALs" title="United States Navy SEALs">US Navy SEALs</a></li> <li><a href="/wiki/Underwater_Construction_Teams" title="Underwater Construction Teams">Underwater Construction Teams</a></li> <li><a href="/wiki/Underwater_Demolition_Command" title="Underwater Demolition Command">Underwater Demolition Command</a></li> <li><a href="/wiki/Underwater_Demolition_Team" title="Underwater Demolition Team">Underwater Demolition Team</a></li> <li><a href="/wiki/Underwater_Offence_(Turkish_Armed_Forces)" title="Underwater Offence (Turkish Armed Forces)">Underwater Offence (Turkish Armed Forces)</a></li> <li><a href="/wiki/UNGERIN" title="UNGERIN">UNGERIN</a></li></ul> </div></td></tr></tbody></table><div> </div></td></tr></tbody></table><div> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Underwater_work" title="Underwater work">Underwater<br />work</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Commercial_offshore_diving" title="Commercial offshore diving">Commercial offshore diving</a></li> <li><a href="/wiki/Dive_leader" title="Dive leader">Dive leader</a></li> <li><a href="/wiki/Diver_training" title="Diver training">Diver training</a> <ul><li><a href="/wiki/Recreational_diver_training" title="Recreational diver training">Recreational diver training</a></li></ul></li> <li><a href="/wiki/Hazmat_diving" title="Hazmat diving">Hazmat diving</a></li> <li><a href="/wiki/Hyperbaric_welding" title="Hyperbaric welding">Hyperbaric welding</a></li> <li><a href="/wiki/Marine_construction" title="Marine construction">Marine construction</a> <ul><li><a href="/wiki/Offshore_construction" title="Offshore construction">Offshore construction</a></li> <li><a href="/wiki/Underwater_construction" title="Underwater construction">Underwater construction</a></li></ul></li> <li><a href="/wiki/Media_diving" title="Media diving">Media diving</a></li> <li><a href="/wiki/Pearl_hunting" title="Pearl hunting">Pearl hunting</a></li> <li><a href="/wiki/Police_diving" title="Police diving">Police diving</a></li> <li><a href="/wiki/Potable_water_diving" title="Potable water diving">Potable water diving</a></li> <li><a href="/wiki/Public_safety_diving" title="Public safety diving">Public safety diving</a></li> <li><a href="/wiki/Scientific_diving" title="Scientific diving">Scientific diving</a></li> <li><a href="/wiki/Ships_husbandry" title="Ships husbandry">Ships husbandry</a></li> <li><a href="/wiki/Sponge_diving" title="Sponge diving">Sponge diving</a></li> <li><a href="/wiki/Submarine_pipeline" title="Submarine pipeline">Submarine pipeline</a></li> <li><a href="/wiki/Underwater_archaeology" title="Underwater archaeology">Underwater archaeology</a> <ul><li><a href="/wiki/Archaeology_of_shipwrecks" title="Archaeology of shipwrecks">Archaeology of shipwrecks</a></li></ul></li> <li><a href="/wiki/Underwater_cutting_and_welding" title="Underwater cutting and welding">Underwater cutting and welding</a></li> <li><a href="/wiki/Underwater_demolition" title="Underwater demolition">Underwater demolition</a></li> <li><a href="/wiki/Underwater_inspection" class="mw-redirect" title="Underwater inspection">Underwater inspection</a> <ul><li><a href="/wiki/Nondestructive_testing" title="Nondestructive testing">Nondestructive testing</a></li></ul></li> <li><a href="/wiki/Underwater_logging" title="Underwater logging">Underwater logging</a></li> <li><a href="/wiki/Underwater_photography" title="Underwater photography">Underwater photography</a></li> <li><a href="/wiki/Underwater_search_and_recovery" title="Underwater search and recovery">Underwater search and recovery</a> <ul><li><a href="/wiki/Underwater_searches" title="Underwater searches">Underwater searches</a></li></ul></li> <li><a href="/wiki/Underwater_videography" title="Underwater videography">Underwater videography</a></li> <li><a href="/wiki/Underwater_survey" title="Underwater survey">Underwater survey</a></li></ul> </div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="Salvage_diving" scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Salvage_diving" title="Salvage diving">Salvage diving</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/SS_Egypt" title="SS Egypt">SS <i>Egypt</i></a></li> <li><a href="/wiki/Kronan_(ship)" title="Kronan (ship)"><i>Kronan</i></a></li> <li><a href="/wiki/La_Belle_(ship)" title="La Belle (ship)"><i>La Belle</i></a></li> <li><a href="/wiki/SS_Laurentic_(1908)" title="SS Laurentic (1908)">SS <i>Laurentic</i></a></li> <li><a href="/wiki/RMS_Lusitania" title="RMS Lusitania">RMS <i>Lusitania</i></a></li> <li><a href="/wiki/Swedish_warship_Mars" title="Swedish warship Mars"><i>Mars</i></a></li> <li><a href="/wiki/Mary_Rose" title="Mary Rose"><i>Mary Rose</i></a></li> <li><a href="/wiki/USS_Monitor" title="USS Monitor">USS <i>Monitor</i></a></li> <li><a href="/wiki/HMS_Royal_George_(1756)" title="HMS Royal George (1756)">HMS <i>Royal George</i></a></li> <li><a href="/wiki/Vasa_(ship)" title="Vasa (ship)"><i>Vasa</i></a></li></ul> </div></td></tr></tbody></table><div> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Diving_contractor" class="mw-redirect" title="Diving contractor">Diving<br />contractors</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Compagnie_maritime_d%27expertises" title="Compagnie maritime d'expertises">COMEX</a></li> <li><a href="/wiki/Helix_Energy_Solutions_Group" title="Helix Energy Solutions Group">Helix Energy Solutions Group</a></li> <li><a href="/wiki/International_Marine_Contractors_Association" title="International Marine Contractors Association">International Marine Contractors Association</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Tools and<br />equipment</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Abrasive_waterjet" class="mw-redirect" title="Abrasive waterjet">Abrasive waterjet</a></li> <li><a href="/wiki/Airlift_(dredging_device)" title="Airlift (dredging device)">Airlift</a></li> <li><a href="/wiki/Baited_remote_underwater_video" title="Baited remote underwater video">Baited remote underwater video</a></li> <li><a href="/wiki/In-water_surface_cleaning" title="In-water surface cleaning">In-water surface cleaning</a> <ul><li>Brush cart</li> <li><a href="/w/index.php?title=Cavitation_cleaning&action=edit&redlink=1" class="new" title="Cavitation cleaning (page does not exist)">Cavitation cleaning</a></li> <li><a href="/wiki/Pressure_washing" title="Pressure washing">Pressure washing</a></li> <li><a href="/wiki/Pigging" title="Pigging">Pigging</a></li></ul></li> <li><a href="/wiki/Hot_stab" title="Hot stab">Hot stab</a></li> <li><a href="/wiki/Lifting_bag" title="Lifting bag">Lifting bag</a></li> <li><a href="/wiki/Remotely_operated_underwater_vehicle" title="Remotely operated underwater vehicle">Remotely operated underwater vehicle</a></li> <li><a href="/wiki/Thermal_lance" title="Thermal lance">Thermal lance</a></li> <li><a href="/wiki/Tremie" title="Tremie">Tremie</a></li> <li><a href="/w/index.php?title=Water_jetting&action=edit&redlink=1" class="new" title="Water jetting (page does not exist)">Water jetting</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Underwater<br />weapons</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Limpet_mine" title="Limpet mine">Limpet mine</a></li> <li><a href="/wiki/Speargun" title="Speargun">Speargun</a> <ul><li><a href="/wiki/Hawaiian_sling" title="Hawaiian sling">Hawaiian sling</a></li> <li><a href="/wiki/Polespear" title="Polespear">Polespear</a></li></ul></li></ul> </div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="Underwaterfirearm" scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Underwater_firearm" title="Underwater firearm">Underwater<br />firearm</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Gyrojet" title="Gyrojet">Gyrojet</a></li> <li><a href="/wiki/Mk_1_Underwater_Defense_Gun" title="Mk 1 Underwater Defense Gun">Mk 1 Underwater Defense Gun</a></li> <li><a href="/wiki/Powerhead_(firearm)" title="Powerhead (firearm)">Powerhead</a></li> <li>Underwater pistols <ul><li><a href="/wiki/Heckler_%26_Koch_P11" title="Heckler & Koch P11">Heckler & Koch P11</a></li> <li><a href="/wiki/SPP-1_underwater_pistol" title="SPP-1 underwater pistol">SPP-1 underwater pistol</a></li></ul></li> <li>Underwater revolvers <ul><li><a href="/wiki/AAI_underwater_revolver" title="AAI underwater revolver">AAI underwater revolver</a></li></ul></li> <li>Underwater rifles <ul><li><a href="/wiki/ADS_amphibious_rifle" title="ADS amphibious rifle">ADS amphibious rifle</a></li> <li><a href="/wiki/APS_underwater_rifle" title="APS underwater rifle">APS underwater rifle</a></li> <li><a href="/wiki/ASM-DT_amphibious_rifle" title="ASM-DT amphibious rifle">ASM-DT amphibious rifle</a></li> <li><a href="/wiki/QBS-06" title="QBS-06">QBS-06</a></li></ul></li></ul> </div></td></tr></tbody></table><div> </div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks mw-collapsible mw-collapsed navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><div id="Recreational_diving" style="font-size:114%;margin:0 4em"><a href="/wiki/Recreational_diving" title="Recreational diving">Recreational diving</a></div></th></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Recreational_dive_sites" title="Recreational dive sites">Recreational dive sites</a></li> <li><a href="/wiki/Index_of_recreational_dive_sites" title="Index of recreational dive sites">Index of recreational dive sites</a></li> <li><a href="/wiki/List_of_wreck_diving_sites" title="List of wreck diving sites">List of wreck diving sites</a></li> <li><a href="/wiki/Outline_of_recreational_dive_sites" title="Outline of recreational dive sites">Outline of recreational dive sites</a></li></ul> </div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">Specialties</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Altitude_diving" title="Altitude diving">Altitude diving</a></li> <li><a href="/wiki/Cave_diving" title="Cave diving">Cave diving</a></li> <li><a href="/wiki/Deep_diving" title="Deep diving">Deep diving</a></li> <li><a href="/wiki/Ice_diving" title="Ice diving">Ice diving</a></li> <li><a href="/wiki/Muck_diving" title="Muck diving">Muck diving</a></li> <li><a href="/wiki/Open-water_diving" title="Open-water diving">Open-water diving</a></li> <li><a class="mw-selflink selflink">Rebreather diving</a></li> <li><a href="/wiki/Sidemount_diving" title="Sidemount diving">Sidemount diving</a></li> <li><a href="/wiki/Solo_diving" title="Solo diving">Solo diving</a></li> <li><a href="/wiki/Technical_diving" title="Technical diving">Technical diving</a></li> <li><a href="/wiki/Underwater_photography" title="Underwater photography">Underwater photography</a></li> <li><a href="/wiki/Wreck_diving" title="Wreck diving">Wreck diving</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Diver_organisations" title="Diver organisations">Diver<br />organisations</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/British_Sub-Aqua_Club" title="British Sub-Aqua Club">British Sub-Aqua Club</a> (BSAC)</li> <li><a href="/wiki/Cave_Divers_Association_of_Australia" title="Cave Divers Association of Australia">Cave Divers Association of Australia</a> (CDAA)</li> <li><a href="/wiki/Cave_Diving_Group" title="Cave Diving Group">Cave Diving Group</a> (CDG)</li> <li><a href="/wiki/Comhairle_Fo-Thuinn" title="Comhairle Fo-Thuinn">Comhairle Fo-Thuinn</a> (CFT)</li> <li><a href="/wiki/Conf%C3%A9d%C3%A9ration_Mondiale_des_Activit%C3%A9s_Subaquatiques" title="Confédération Mondiale des Activités Subaquatiques">Confédération Mondiale des Activités Subaquatiques</a> (CMAS)</li> <li><a href="/wiki/Federaci%C3%B3n_Espa%C3%B1ola_de_Actividades_Subacu%C3%A1ticas" title="Federación Española de Actividades Subacuáticas">Federación Española de Actividades Subacuáticas</a> (FEDAS)</li> <li><a href="/wiki/F%C3%A9d%C3%A9ration_Fran%C3%A7aise_d%27%C3%89tudes_et_de_Sports_Sous-Marins" title="Fédération Française d'Études et de Sports Sous-Marins">Fédération Française d'Études et de Sports Sous-Marins</a> (FFESSM)</li> <li><a href="/wiki/International_Association_for_Handicapped_Divers" title="International Association for Handicapped Divers">International Association for Handicapped Divers</a> (IAHD)</li> <li><a href="/wiki/Quintana_Roo_Speleological_Survey" title="Quintana Roo Speleological Survey">Quintana Roo Speleological Survey</a> (QRSS)</li> <li><a href="/wiki/Woodville_Karst_Plain_Project" title="Woodville Karst Plain Project">Woodville Karst Plain Project</a> (WKPP)</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Diving tourism<br />industry</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Dive_center" title="Dive center">Dive center</a></li> <li><a href="/wiki/Diving_in_East_Timor" title="Diving in East Timor">Diving in East Timor</a></li> <li><a href="/wiki/Diving_in_the_Maldives" title="Diving in the Maldives">Diving in the Maldives</a></li> <li><a href="/wiki/Environmental_impact_of_recreational_diving" title="Environmental impact of recreational diving">Environmental impact of recreational diving</a></li> <li><a href="/wiki/Scuba_diving_tourism" title="Scuba diving tourism">Scuba diving tourism</a></li> <li><a href="/wiki/Scuba_diving_in_the_Cayman_Islands" title="Scuba diving in the Cayman Islands">Scuba diving in the Cayman Islands</a></li> <li><a href="/wiki/Shark_tourism" title="Shark tourism">Shark tourism</a></li> <li><a href="/wiki/Sinking_ships_for_wreck_diving_sites" title="Sinking ships for wreck diving sites">Sinking ships for wreck diving sites</a></li> <li><a href="/wiki/Underwater_diving_on_Guam" class="mw-redirect" title="Underwater diving on Guam">Underwater diving on Guam</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Diving events<br />and festivals</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Diversnight" title="Diversnight">Diversnight</a></li> <li><a href="/wiki/Underwater_Bike_Race" title="Underwater Bike Race">Underwater Bike Race</a></li></ul> </div></td></tr></tbody></table><div> </div></td></tr></tbody></table><div></div></td></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks mw-collapsible uncollapsed navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><div id="Diving_safety" style="font-size:114%;margin:0 4em"><a href="/wiki/Diving_safety" title="Diving safety">Diving safety</a></div></th></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Human_factors_in_diving_equipment_design" title="Human factors in diving equipment design">Human factors in diving equipment design</a></li> <li><a href="/wiki/Human_factors_in_diving_safety" title="Human factors in diving safety">Human factors in diving safety</a></li> <li><a href="/wiki/Life-support_system" title="Life-support system">Life-support system</a></li> <li><a href="/wiki/Safety-critical_system" title="Safety-critical system">Safety-critical system</a></li> <li><a href="/wiki/Scuba_diving_fatalities" title="Scuba diving fatalities">Scuba diving fatalities</a></li> <li><a href="/wiki/Underwater_diving_emergency" title="Underwater diving emergency">Underwater diving emergency</a></li> <li><a href="/wiki/Water_safety" title="Water safety">Water safety</a></li> <li><a href="/wiki/Water_surface_searches" title="Water surface searches">Water surface searches</a></li></ul> </div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Diving_hazards" title="Diving hazards">Diving<br />hazards</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/List_of_diving_hazards_and_precautions" title="List of diving hazards and precautions">List of diving hazards and precautions</a></li> <li><a href="/wiki/Hazards_of_the_diving_environment" class="mw-redirect" title="Hazards of the diving environment">Environmental</a> <ul><li><a href="/wiki/Ocean_current" title="Ocean current">Current</a></li> <li><a href="/wiki/Delta-P_(hazard)" class="mw-redirect" title="Delta-P (hazard)">Delta-P</a></li> <li><a href="/wiki/Entanglement_(hazard)" class="mw-redirect" title="Entanglement (hazard)">Entanglement hazard</a></li> <li><a href="/wiki/Penetration_diving" title="Penetration diving">Overhead</a></li> <li><a href="/wiki/Silt_out" title="Silt out">Silt out</a></li> <li><a href="/wiki/Wave_action" class="mw-redirect" title="Wave action">Wave action</a></li></ul></li> <li>Equipment <ul><li><a href="/wiki/Freeflow" title="Freeflow">Freeflow</a></li> <li><a href="/wiki/List_of_diving_hazards_and_precautions#Use_of_breathing_equipment_in_an_underwater_environment" title="List of diving hazards and precautions">Use of breathing equipment in an underwater environment</a></li> <li><a href="/wiki/List_of_diving_hazards_and_precautions#Failure_of_diving_equipment_other_than_breathing_apparatus" title="List of diving hazards and precautions">Failure of diving equipment other than breathing apparatus</a></li> <li><a href="/wiki/Single_point_of_failure" title="Single point of failure">Single point of failure</a></li></ul></li> <li>Physiological <ul><li><a href="/wiki/Cold_shock_response" title="Cold shock response">Cold shock response</a></li> <li><a href="/wiki/Decompression_(diving)" title="Decompression (diving)">Decompression</a></li> <li><a href="/wiki/Nitrogen_narcosis" title="Nitrogen narcosis">Nitrogen narcosis</a></li> <li><a href="/wiki/Oxygen_toxicity" title="Oxygen toxicity">Oxygen toxicity</a></li> <li><a href="/wiki/Seasickness" class="mw-redirect" title="Seasickness">Seasickness</a></li> <li><a href="/wiki/Uncontrolled_decompression" title="Uncontrolled decompression">Uncontrolled decompression</a></li></ul></li> <li><a href="/wiki/List_of_diving_hazards_and_precautions#Diver_behaviour_and_competence" title="List of diving hazards and precautions">Diver behaviour and competence</a> <ul><li>Lack of <a href="/wiki/Competence_(human_resources)" title="Competence (human resources)">competence</a></li> <li><a href="/wiki/Overconfidence_effect" title="Overconfidence effect">Overconfidence effect</a></li> <li><a href="/wiki/Panic" title="Panic">Panic</a></li> <li><a href="/wiki/Task_loading" title="Task loading">Task loading</a></li> <li><a href="/wiki/Anxiety#Trait" title="Anxiety">Trait anxiety</a></li> <li><a href="/wiki/Willful_violation" title="Willful violation">Willful violation</a></li></ul></li></ul> </div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="Consequences" scope="row" class="navbox-group" style="width:1%">Consequences</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Barotrauma" title="Barotrauma">Barotrauma</a></li> <li><a href="/wiki/Decompression_sickness" title="Decompression sickness">Decompression sickness</a></li> <li><a href="/wiki/Drowning" title="Drowning">Drowning</a></li> <li><a href="/wiki/Hypothermia" title="Hypothermia">Hypothermia</a></li> <li><a href="/wiki/Hypoxia_(medical)" class="mw-redirect" title="Hypoxia (medical)">Hypoxia</a></li> <li><a href="/wiki/Hypercapnia" title="Hypercapnia">Hypercapnia</a></li> <li><a href="/wiki/Hyperthermia" title="Hyperthermia">Hyperthermia</a></li> <li><a href="/wiki/Non-freezing_cold_injury" title="Non-freezing cold injury">Non-freezing cold injury</a></li></ul> </div></td></tr></tbody></table><div> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Diving_procedures" title="Diving procedures">Diving<br />procedures</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Ascending_and_descending_(diving)" title="Ascending and descending (diving)">Ascending and descending</a> <ul><li><a href="/wiki/Emergency_ascent" title="Emergency ascent">Emergency ascent</a></li></ul></li> <li><a href="/wiki/Boat_diving" class="mw-redirect" title="Boat diving">Boat diving</a> <ul><li><a href="/wiki/Canoe_and_kayak_diving" title="Canoe and kayak diving">Canoe and kayak diving</a></li></ul></li> <li><a href="/wiki/Buddy_diving" title="Buddy diving">Buddy diving</a> <ul><li><a href="/wiki/Buddy_check" title="Buddy check">buddy check</a></li></ul></li> <li><a href="/wiki/Decompression_(diving)" title="Decompression (diving)">Decompression</a> <ul><li><a href="/wiki/Decompression_practice" title="Decompression practice">Decompression practice</a></li> <li><a href="/wiki/Pyle_stop" title="Pyle stop">Pyle stop</a></li> <li><a href="/wiki/Ratio_decompression" title="Ratio decompression">Ratio decompression</a></li></ul></li> <li><a href="/wiki/Dive_briefing" title="Dive briefing">Dive briefing</a></li> <li><a href="/wiki/Dive_log" title="Dive log">Dive log</a></li> <li><a href="/wiki/Dive_planning" title="Dive planning">Dive planning</a> <ul><li><a href="/wiki/Rule_of_thirds_(diving)" title="Rule of thirds (diving)">Rule of thirds</a></li> <li><a href="/wiki/Scuba_gas_planning" title="Scuba gas planning">Scuba gas planning</a></li></ul></li> <li><a href="/wiki/Diver_communications" title="Diver communications">Diver communications</a></li> <li><a href="/wiki/Diver_rescue" title="Diver rescue">Diver rescue</a></li> <li><a href="/wiki/Diver_training" title="Diver training">Diver training</a></li> <li><a href="/wiki/Doing_It_Right_(scuba_diving)" title="Doing It Right (scuba diving)">Doing It Right</a></li> <li><a href="/wiki/Drift_diving" title="Drift diving">Drift diving</a></li> <li><a href="/wiki/Gas_blending_for_scuba_diving" title="Gas blending for scuba diving">Gas blending for scuba diving</a></li> <li><a href="/wiki/Night_diving" title="Night diving">Night diving</a></li> <li><a class="mw-selflink selflink">Rebreather diving</a></li> <li><a href="/wiki/Scuba_gas_management" title="Scuba gas management">Scuba gas management</a></li> <li><a href="/wiki/Solo_diving" title="Solo diving">Solo diving</a></li> <li><a href="/wiki/Wall_diving" title="Wall diving">Wall diving</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Risk_management" title="Risk management">Risk<br />management</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Checklist" title="Checklist">Checklist</a></li> <li>Hazard identification and risk assessment <ul><li><a href="/wiki/Hazard_analysis" title="Hazard analysis">Hazard analysis</a></li> <li><a href="/wiki/Job_safety_analysis" title="Job safety analysis">Job safety analysis</a></li> <li><a href="/wiki/Risk_assessment" title="Risk assessment">Risk assessment</a></li></ul></li> <li><a href="/wiki/Hyperbaric_evacuation_and_rescue" title="Hyperbaric evacuation and rescue">Hyperbaric evacuation and rescue</a></li> <li><a href="/wiki/Risk_control" title="Risk control">Risk control</a> <ul><li><a href="/wiki/Hierarchy_of_hazard_controls" title="Hierarchy of hazard controls">Hierarchy of hazard controls</a></li></ul></li> <li><a href="/wiki/Incident_pit" title="Incident pit">Incident pit</a></li> <li><a href="/wiki/Lockout%E2%80%93tagout" title="Lockout–tagout">Lockout–tagout</a></li> <li><a href="/wiki/Permit_To_Work" class="mw-redirect" title="Permit To Work">Permit To Work</a></li> <li><a href="/wiki/Redundancy_(engineering)" title="Redundancy (engineering)">Redundancy</a></li> <li><a href="/wiki/Safety_data_sheet" title="Safety data sheet">Safety data sheet</a></li> <li><a href="/wiki/Situation_awareness" title="Situation awareness">Situation awareness</a></li></ul> </div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Diving_team" title="Diving team">Diving team</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Bellman_(diving)" class="mw-redirect" title="Bellman (diving)">Bellman</a></li> <li><a href="/wiki/Chamber_operator" class="mw-redirect" title="Chamber operator">Chamber operator</a></li> <li><a href="/wiki/Diver_medical_technician" class="mw-redirect" title="Diver medical technician">Diver medical technician</a></li> <li><a href="/wiki/Diver%27s_attendant" class="mw-redirect" title="Diver's attendant">Diver's attendant</a></li> <li><a href="/wiki/Diving_supervisor" title="Diving supervisor">Diving supervisor</a></li> <li><a href="/wiki/Diving_systems_technician" class="mw-redirect" title="Diving systems technician">Diving systems technician</a></li> <li><a href="/wiki/Gas_man" class="mw-redirect" title="Gas man">Gas man</a></li> <li><a href="/wiki/Life_support_technician" class="mw-redirect" title="Life support technician">Life support technician</a></li> <li><a href="/wiki/Stand-by_diver" class="mw-redirect" title="Stand-by diver">Stand-by diver</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Equipment<br />safety</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Breathing_gas_quality" class="mw-redirect" title="Breathing gas quality">Breathing gas quality</a></li> <li><a href="/wiki/Testing_and_inspection_of_diving_cylinders" title="Testing and inspection of diving cylinders">Testing and inspection of diving cylinders</a> <ul><li><a href="/wiki/Hydrostatic_test" title="Hydrostatic test">Hydrostatic test</a></li> <li><a href="/wiki/Sustained_load_cracking" title="Sustained load cracking">Sustained load cracking</a></li></ul></li> <li><a href="/wiki/Diving_regulator" title="Diving regulator">Diving regulator</a> <ul><li><a href="/wiki/Breathing_performance_of_regulators" title="Breathing performance of regulators">Breathing performance of regulators</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Occupational_safety_and_health" title="Occupational safety and health">Occupational<br />safety and<br />health</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Association_of_Diving_Contractors_International" title="Association of Diving Contractors International">Association of Diving Contractors International</a></li> <li><a href="/wiki/International_Marine_Contractors_Association" title="International Marine Contractors Association">International Marine Contractors Association</a></li> <li><a href="/wiki/Code_of_practice" title="Code of practice">Code of practice</a></li> <li><a href="/wiki/Contingency_plan" title="Contingency plan">Contingency plan</a></li> <li><a href="/wiki/Diving_regulations" title="Diving regulations">Diving regulations</a></li> <li><a href="/wiki/Emergency_response_plan" class="mw-redirect" title="Emergency response plan">Emergency response plan</a></li> <li><a href="/wiki/Diving_safety_officer" title="Diving safety officer">Diving safety officer</a></li> <li><a href="/wiki/Diving_superintendent" class="mw-redirect" title="Diving superintendent">Diving superintendent</a></li> <li><a href="/wiki/Diving_supervisor" title="Diving supervisor">Diving supervisor</a></li> <li><a href="/wiki/Operations_manual" title="Operations manual">Operations manual</a></li> <li><a href="/wiki/Standard_operating_procedure" title="Standard operating procedure">Standard operating procedure</a></li></ul> </div></td></tr></tbody></table><div> </div></td></tr></tbody></table><div> </div></td></tr></tbody></table><div></div></td></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks mw-collapsible mw-collapsed navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><div id="Diving_medicine" style="font-size:114%;margin:0 4em"><a href="/wiki/Diving_medicine" title="Diving medicine">Diving medicine</a></div></th></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Diving_disorders" title="Diving disorders">Diving<br />disorders</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/List_of_signs_and_symptoms_of_diving_disorders" title="List of signs and symptoms of diving disorders">List of signs and symptoms of diving disorders</a></li> <li><a href="/wiki/Cramp" title="Cramp">Cramp</a></li> <li><a href="/wiki/Motion_sickness" title="Motion sickness">Motion sickness</a></li> <li><a href="/wiki/Surfer%27s_ear" title="Surfer's ear">Surfer's ear</a></li></ul> </div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">Pressure<br />related</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Alternobaric_vertigo" title="Alternobaric vertigo">Alternobaric vertigo</a></li> <li><a href="/wiki/Barostriction" class="mw-redirect" title="Barostriction">Barostriction</a></li> <li><a href="/wiki/Barotrauma" title="Barotrauma">Barotrauma</a> <ul><li><a href="/wiki/Air_embolism" title="Air embolism">Air embolism</a></li> <li><a href="/wiki/Aerosinusitis" title="Aerosinusitis">Aerosinusitis</a></li> <li><a href="/wiki/Barodontalgia" title="Barodontalgia">Barodontalgia</a></li> <li><a href="/wiki/Dental_barotrauma" class="mw-redirect" title="Dental barotrauma">Dental barotrauma</a></li> <li><a href="/wiki/Middle_ear_barotrauma" title="Middle ear barotrauma">Middle ear barotrauma</a></li> <li><a href="/wiki/Pulmonary_barotrauma" class="mw-redirect" title="Pulmonary barotrauma">Pulmonary barotrauma</a></li></ul></li> <li><a href="/wiki/Compression_arthralgia" title="Compression arthralgia">Compression arthralgia</a></li> <li><a href="/wiki/Decompression_illness" title="Decompression illness">Decompression illness</a></li> <li><a href="/wiki/Dysbarism" title="Dysbarism">Dysbarism</a></li></ul> </div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">Oxygen</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Freediving_blackout" title="Freediving blackout">Freediving blackout</a></li> <li><a href="/wiki/Hyperoxia" title="Hyperoxia">Hyperoxia</a></li> <li><a href="/wiki/Hypoxia_(medical)" class="mw-redirect" title="Hypoxia (medical)">Hypoxia</a></li> <li><a href="/wiki/Oxygen_toxicity" title="Oxygen toxicity">Oxygen toxicity</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Inert gases</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Avascular_necrosis" title="Avascular necrosis">Avascular necrosis</a></li> <li><a href="/wiki/Decompression_sickness" title="Decompression sickness">Decompression sickness</a> <ul><li><a href="/wiki/Dysbaric_osteonecrosis" title="Dysbaric osteonecrosis">Dysbaric osteonecrosis</a></li> <li><a href="/wiki/Inner_ear_decompression_sickness" title="Inner ear decompression sickness">Inner ear decompression sickness</a></li> <li><a href="/wiki/Isobaric_counterdiffusion" title="Isobaric counterdiffusion">Isobaric counterdiffusion</a></li> <li><a href="/wiki/Taravana" title="Taravana">Taravana</a></li></ul></li> <li><a href="/wiki/High-pressure_nervous_syndrome" title="High-pressure nervous syndrome">High-pressure nervous syndrome</a></li> <li><a href="/wiki/Hydrogen_narcosis" title="Hydrogen narcosis">Hydrogen narcosis</a></li> <li><a href="/wiki/Nitrogen_narcosis" title="Nitrogen narcosis">Nitrogen narcosis</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Carbon dioxide</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Hypercapnia" title="Hypercapnia">Hypercapnia</a></li> <li><a href="/wiki/Hypocapnia" title="Hypocapnia">Hypocapnia</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Breathing gas<br />contaminants</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Carbon_monoxide_poisoning" title="Carbon monoxide poisoning">Carbon monoxide poisoning</a></li></ul> </div></td></tr></tbody></table><div> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Immersion<br />related</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Asphyxia" title="Asphyxia">Asphyxia</a></li> <li><a href="/wiki/Drowning" title="Drowning">Drowning</a></li> <li><a href="/wiki/Hypothermia" title="Hypothermia">Hypothermia</a></li> <li><a href="/wiki/Immersion_diuresis" class="mw-redirect" title="Immersion diuresis">Immersion diuresis</a></li> <li><a href="/wiki/Instinctive_drowning_response" title="Instinctive drowning response">Instinctive drowning response</a></li> <li><a href="/wiki/Laryngospasm" title="Laryngospasm">Laryngospasm</a></li> <li><a href="/wiki/Salt_water_aspiration_syndrome" title="Salt water aspiration syndrome">Salt water aspiration syndrome</a></li> <li><a href="/wiki/Swimming-induced_pulmonary_edema" title="Swimming-induced pulmonary edema">Swimming-induced pulmonary edema</a></li></ul> </div></td></tr></tbody></table><div> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Treatment</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Demand_valve_oxygen_therapy" title="Demand valve oxygen therapy">Demand valve oxygen therapy</a></li> <li><a href="/wiki/First_aid" title="First aid">First aid</a></li> <li><a href="/wiki/Hyperbaric_medicine" title="Hyperbaric medicine">Hyperbaric medicine</a></li> <li><a href="/wiki/Hyperbaric_treatment_schedules" title="Hyperbaric treatment schedules">Hyperbaric treatment schedules</a></li> <li><a href="/wiki/In-water_recompression" title="In-water recompression">In-water recompression</a></li> <li><a href="/wiki/Oxygen_therapy" title="Oxygen therapy">Oxygen therapy</a></li> <li><a href="/wiki/Therapeutic_recompression" class="mw-redirect" title="Therapeutic recompression">Therapeutic recompression</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Personnel</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Diving_Medical_Examiner" class="mw-redirect" title="Diving Medical Examiner">Diving Medical Examiner</a></li> <li><a href="/wiki/Diving_Medical_Practitioner" class="mw-redirect" title="Diving Medical Practitioner">Diving Medical Practitioner</a></li> <li><a href="/wiki/Diving_Medical_Technician" class="mw-redirect" title="Diving Medical Technician">Diving Medical Technician</a></li> <li><a href="/wiki/Hyperbaric_nursing" title="Hyperbaric nursing">Hyperbaric nursing</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Screening</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Atrial_septal_defect" title="Atrial septal defect">Atrial septal defect</a></li> <li><a href="/wiki/Effects_of_drugs_on_fitness_to_dive" class="mw-redirect" title="Effects of drugs on fitness to dive">Effects of drugs on fitness to dive</a></li> <li><a href="/wiki/Fitness_to_dive" title="Fitness to dive">Fitness to dive</a></li> <li><a href="/wiki/Psychological_fitness_to_dive" class="mw-redirect" title="Psychological fitness to dive">Psychological fitness to dive</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Research</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/List_of_researchers_in_diving_physiology_and_medicine" class="mw-redirect" title="List of researchers in diving physiology and medicine">Researchers in<br />diving physiology<br />and medicine</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Arthur_J._Bachrach" title="Arthur J. Bachrach">Arthur J. Bachrach</a></li> <li><a href="/wiki/Albert_R._Behnke" title="Albert R. Behnke">Albert R. Behnke</a></li> <li><a href="/wiki/Peter_B._Bennett" title="Peter B. Bennett">Peter B. Bennett</a></li> <li><a href="/wiki/Paul_Bert" title="Paul Bert">Paul Bert</a></li> <li><a href="/wiki/George_F._Bond" title="George F. Bond">George F. Bond</a></li> <li><a href="/wiki/Robert_Boyle" title="Robert Boyle">Robert Boyle</a></li> <li><a href="/wiki/Alf_O._Brubakk" title="Alf O. Brubakk">Alf O. Brubakk</a></li> <li><a href="/wiki/Albert_A._B%C3%BChlmann" title="Albert A. Bühlmann">Albert A. Bühlmann</a></li> <li><a href="/wiki/John_R._Clarke_(scientist)" title="John R. Clarke (scientist)">John R. Clarke</a></li> <li><a href="/wiki/Guybon_Chesney_Castell_Damant" title="Guybon Chesney Castell Damant">Guybon Chesney Castell Damant</a></li> <li><a href="/wiki/Kenneth_William_Donald" title="Kenneth William Donald">Kenneth William Donald</a></li> <li><a href="/wiki/William_Paul_Fife" title="William Paul Fife">William Paul Fife</a></li> <li><a href="/wiki/John_Scott_Haldane" title="John Scott Haldane">John Scott Haldane</a></li> <li><a href="/wiki/Robert_William_Hamilton_Jr." title="Robert William Hamilton Jr.">Robert William Hamilton Jr.</a></li> <li><a href="/wiki/Henry_Valence_Hempleman" title="Henry Valence Hempleman">Henry Valence Hempleman</a></li> <li><a href="/wiki/Leonard_Erskine_Hill" class="mw-redirect" title="Leonard Erskine Hill">Leonard Erskine Hill</a></li> <li><a href="/wiki/Brian_Andrew_Hills" title="Brian Andrew Hills">Brian Andrew Hills</a></li> <li><a href="/wiki/Felix_Hoppe-Seyler" title="Felix Hoppe-Seyler">Felix Hoppe-Seyler</a></li> <li><a href="/wiki/Christian_J._Lambertsen" title="Christian J. Lambertsen">Christian J. Lambertsen</a></li> <li><a href="/wiki/Simon_Mitchell" title="Simon Mitchell">Simon Mitchell</a></li> <li><a href="/wiki/Charles_Momsen" title="Charles Momsen">Charles Momsen</a></li> <li><a href="/wiki/Neal_W._Pollock" title="Neal W. Pollock">Neal W. Pollock</a></li> <li><a href="/wiki/John_Rawlins_(Royal_Navy_officer)" title="John Rawlins (Royal Navy officer)">John Rawlins</a></li> <li><a href="/wiki/Charles_Wesley_Shilling" title="Charles Wesley Shilling">Charles Wesley Shilling</a></li> <li><a href="/wiki/Edward_D._Thalmann" title="Edward D. Thalmann">Edward D. Thalmann</a></li> <li><a href="/wiki/Jacques_Triger" title="Jacques Triger">Jacques Triger</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Diving medical<br />research<br />organisations</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Aerospace_Medical_Association" title="Aerospace Medical Association">Aerospace Medical Association</a></li> <li><a href="/wiki/Divers_Alert_Network" title="Divers Alert Network">Divers Alert Network</a> (DAN)</li> <li><a href="/wiki/Diving_Diseases_Research_Centre" class="mw-redirect" title="Diving Diseases Research Centre">Diving Diseases Research Centre</a> (DDRC)</li> <li><a href="/wiki/Diving_Medical_Advisory_Council" title="Diving Medical Advisory Council">Diving Medical Advisory Council</a> (DMAC)</li> <li><a href="/wiki/European_Diving_Technology_Committee" title="European Diving Technology Committee">European Diving Technology Committee</a> (EDTC)</li> <li><a href="/wiki/European_Underwater_and_Baromedical_Society" title="European Underwater and Baromedical Society">European Underwater and Baromedical Society</a> (EUBS)</li> <li><a href="/wiki/National_Board_of_Diving_and_Hyperbaric_Medical_Technology" title="National Board of Diving and Hyperbaric Medical Technology">National Board of Diving and Hyperbaric Medical Technology</a></li> <li><a href="/wiki/Naval_Submarine_Medical_Research_Laboratory" title="Naval Submarine Medical Research Laboratory">Naval Submarine Medical Research Laboratory</a></li> <li><a href="/wiki/Royal_Australian_Navy_School_of_Underwater_Medicine" title="Royal Australian Navy School of Underwater Medicine">Royal Australian Navy School of Underwater Medicine</a></li> <li><a href="/wiki/Rubicon_Foundation" title="Rubicon Foundation">Rubicon Foundation</a></li> <li><a href="/wiki/South_Pacific_Underwater_Medicine_Society" title="South Pacific Underwater Medicine Society">South Pacific Underwater Medicine Society</a> (SPUMS)</li> <li><a href="/wiki/Southern_African_Underwater_and_Hyperbaric_Medical_Association" title="Southern African Underwater and Hyperbaric Medical Association">Southern African Underwater and Hyperbaric Medical Association</a> (SAUHMA)</li> <li><a href="/wiki/Undersea_and_Hyperbaric_Medical_Society" title="Undersea and Hyperbaric Medical Society">Undersea and Hyperbaric Medical Society</a> (UHMS)</li> <li><a href="/wiki/United_States_Navy_Experimental_Diving_Unit" title="United States Navy Experimental Diving Unit">United States Navy Experimental Diving Unit</a> (NEDU)</li></ul> </div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks mw-collapsible mw-collapsed navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><div id="Law" style="font-size:114%;margin:0 4em">Law</div></th></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Civil_liability_in_recreational_diving" title="Civil liability in recreational diving">Civil liability in recreational diving</a></li> <li><a href="/wiki/Diving_regulations" title="Diving regulations">Diving regulations</a></li> <li><a href="/wiki/Duty_of_care" title="Duty of care">Duty of care</a></li> <li><a href="/wiki/List_of_legislation_regulating_underwater_diving" title="List of legislation regulating underwater diving">List of legislation regulating underwater diving</a></li> <li><a href="/wiki/Investigation_of_diving_accidents" title="Investigation of diving accidents">Investigation of diving accidents</a></li> <li><a href="/wiki/Convention_on_the_Protection_of_the_Underwater_Cultural_Heritage" title="Convention on the Protection of the Underwater Cultural Heritage">Convention on the Protection of the Underwater Cultural Heritage</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks mw-collapsible mw-collapsed navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><div id="History_of_underwater_diving" style="font-size:114%;margin:0 4em"><a href="/wiki/History_of_underwater_diving" title="History of underwater diving">History of underwater diving</a></div></th></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/History_of_decompression_research_and_development" title="History of decompression research and development">History of decompression research and development</a></li> <li><a href="/wiki/History_of_Diving_Museum" title="History of Diving Museum">History of Diving Museum</a></li> <li><a href="/wiki/History_of_scuba_diving" title="History of scuba diving">History of scuba diving</a></li> <li><a href="/wiki/List_of_researchers_in_underwater_diving" title="List of researchers in underwater diving">List of researchers in underwater diving</a></li> <li><a href="/wiki/Lyons_Maritime_Museum" title="Lyons Maritime Museum">Lyons Maritime Museum</a></li> <li><a href="/wiki/Man_in_the_Sea_Museum" title="Man in the Sea Museum">Man in the Sea Museum</a></li> <li><a href="/wiki/Timeline_of_diving_technology" title="Timeline of diving technology">Timeline of diving technology</a></li> <li><a href="/wiki/Pearling_in_Western_Australia" title="Pearling in Western Australia">Pearling in Western Australia</a></li> <li><a href="/wiki/US_Navy_decompression_models_and_tables" title="US Navy decompression models and tables">US Navy decompression models and tables</a></li></ul> </div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">Archeological<br />sites</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/SS_Commodore" title="SS Commodore">SS <i>Commodore</i></a></li> <li><a href="/wiki/USS_Monitor" title="USS Monitor">USS <i>Monitor</i></a></li> <li><i><a href="/wiki/Queen_Anne%27s_Revenge" title="Queen Anne's Revenge">Queen Anne's Revenge</a></i></li> <li><i><a href="/wiki/Whydah_Gally" title="Whydah Gally">Whydah Gally</a></i></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Underwater art<br />and artists</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/The_Diver" title="The Diver">The Diver</a></li> <li><a href="/wiki/Jason_deCaires_Taylor" title="Jason deCaires Taylor">Jason deCaires Taylor</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Engineers<br />and inventors</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Jer%C3%B3nimo_de_Ayanz_y_Beaumont" title="Jerónimo de Ayanz y Beaumont">Jerónimo de Ayanz y Beaumont</a></li> <li><a href="/wiki/William_Beebe" title="William Beebe">William Beebe</a></li> <li><a href="/wiki/Georges_Beuchat" title="Georges Beuchat">Georges Beuchat</a></li> <li><a href="/wiki/Giovanni_Alfonso_Borelli" title="Giovanni Alfonso Borelli">Giovanni Alfonso Borelli</a></li> <li><a href="/wiki/Joseph-Martin_Cabirol" title="Joseph-Martin Cabirol">Joseph-Martin Cabirol</a></li> <li><a href="/wiki/John_R._Clarke_(scientist)" title="John R. Clarke (scientist)">John R. Clarke</a></li> <li><a href="/wiki/Jacques_Cousteau" title="Jacques Cousteau">Jacques Cousteau</a></li> <li><a href="/wiki/Charles_Anthony_Deane" title="Charles Anthony Deane">Charles Anthony Deane</a></li> <li><a href="/wiki/John_Deane_(inventor)" title="John Deane (inventor)">John Deane</a></li> <li><a href="/wiki/Louis_de_Corlieu" title="Louis de Corlieu">Louis de Corlieu</a></li> <li><a href="/wiki/Auguste_Denayrouze" title="Auguste Denayrouze">Auguste Denayrouze</a></li> <li><a href="/wiki/Ted_Eldred" title="Ted Eldred">Ted Eldred</a></li> <li><a href="/wiki/Henry_Fleuss" title="Henry Fleuss">Henry Fleuss</a></li> <li><a href="/wiki/%C3%89mile_Gagnan" title="Émile Gagnan">Émile Gagnan</a></li> <li><a href="/wiki/Karl_Heinrich_Klingert" title="Karl Heinrich Klingert">Karl Heinrich Klingert</a></li> <li><a href="/wiki/Peter_Kreeft_(diver)" title="Peter Kreeft (diver)">Peter Kreeft</a></li> <li><a href="/wiki/Christian_J._Lambertsen" title="Christian J. Lambertsen">Christian J. Lambertsen</a></li> <li><a href="/wiki/Yves_Le_Prieur" title="Yves Le Prieur">Yves Le Prieur</a></li> <li><a href="/wiki/John_Lethbridge" title="John Lethbridge">John Lethbridge</a></li> <li><a href="/wiki/Ernest_William_Moir" title="Ernest William Moir">Ernest William Moir</a></li> <li><a href="/wiki/Joseph_Salim_Peress" title="Joseph Salim Peress">Joseph Salim Peress</a></li> <li><a href="/wiki/Auguste_Piccard" title="Auguste Piccard">Auguste Piccard</a></li> <li><a href="/wiki/Joe_Savoie" title="Joe Savoie">Joe Savoie</a></li> <li><a href="/wiki/Willard_Franklyn_Searle" title="Willard Franklyn Searle">Willard Franklyn Searle</a></li> <li><a href="/wiki/Gordon_Smith_(inventor)" title="Gordon Smith (inventor)">Gordon Smith</a></li> <li><a href="/wiki/Augustus_Siebe" title="Augustus Siebe">Augustus Siebe</a></li> <li><a href="/wiki/Pierre-Marie_Touboulic" title="Pierre-Marie Touboulic">Pierre-Marie Touboulic</a></li> <li><a href="/wiki/Jacques_Triger" title="Jacques Triger">Jacques Triger</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Historical<br />equipment</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Aqua-Lung" title="Aqua-Lung">Aqua-Lung</a></li> <li><a href="/wiki/RV_Calypso" title="RV Calypso">RV <i>Calypso</i></a></li> <li><a href="/wiki/SP-350_Denise" title="SP-350 Denise">SP-350 <i>Denise</i></a></li> <li><a href="/wiki/Magnesium_torch" title="Magnesium torch">Magnesium torch</a></li> <li><a href="/wiki/Nikonos" title="Nikonos">Nikonos</a></li> <li><a href="/wiki/Porpoise_(scuba_gear)" title="Porpoise (scuba gear)">Porpoise regulator</a></li> <li><a href="/wiki/Standard_diving_dress" title="Standard diving dress">Standard diving dress</a></li> <li><a href="/wiki/Sub_Marine_Explorer" title="Sub Marine Explorer">Sub Marine Explorer</a></li> <li><a href="/wiki/Vintage_scuba" title="Vintage scuba">Vintage scuba</a></li></ul> </div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="Diverpropulsionvehicles" scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Diver_propulsion_vehicle" title="Diver propulsion vehicle">Diver<br />propulsion<br />vehicles</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Advanced_SEAL_Delivery_System" title="Advanced SEAL Delivery System">Advanced SEAL Delivery System</a></li> <li><a href="/wiki/Cosmos_CE2F_series" title="Cosmos CE2F series">Cosmos CE2F series</a></li> <li><a href="/wiki/Dry_Combat_Submersible" title="Dry Combat Submersible">Dry Combat Submersible</a></li> <li><a href="/wiki/Human_torpedo" title="Human torpedo">Human torpedo</a></li> <li><a href="/wiki/Motorised_Submersible_Canoe" title="Motorised Submersible Canoe">Motorised Submersible Canoe</a></li> <li><a href="/wiki/Necker_Nymph" title="Necker Nymph">Necker Nymph</a></li> <li><a href="/wiki/R-2_Mala-class_swimmer_delivery_vehicle" title="R-2 Mala-class swimmer delivery vehicle">R-2 Mala-class swimmer delivery vehicle</a></li> <li><a href="/wiki/SEAL_Delivery_Vehicle" title="SEAL Delivery Vehicle">SEAL Delivery Vehicle</a></li> <li><a href="/wiki/Shallow_Water_Combat_Submersible" title="Shallow Water Combat Submersible">Shallow Water Combat Submersible</a></li> <li><a href="/wiki/Siluro_San_Bartolomeo" title="Siluro San Bartolomeo">Siluro San Bartolomeo</a></li> <li><a href="/wiki/Welfreighter" title="Welfreighter">Welfreighter</a></li> <li><a href="/wiki/Wet_Nellie" title="Wet Nellie">Wet Nellie</a></li></ul> </div></td></tr></tbody></table><div> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Military and<br />covert operations</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Raid_on_Alexandria_(1941)" title="Raid on Alexandria (1941)">Raid on Alexandria (1941)</a></li> <li><a href="/wiki/Sinking_of_the_Rainbow_Warrior" title="Sinking of the Rainbow Warrior">Sinking of the <i>Rainbow Warrior</i></a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Scientific projects</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/1992_cageless_shark-diving_expedition" title="1992 cageless shark-diving expedition">1992 cageless shark-diving expedition</a></li> <li><a href="/wiki/Mission_31" title="Mission 31">Mission 31</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Awards and events</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Hans_Hass_Award" title="Hans Hass Award">Hans Hass Award</a></li> <li><a href="/wiki/International_Scuba_Diving_Hall_of_Fame" title="International Scuba Diving Hall of Fame">International Scuba Diving Hall of Fame</a></li> <li><a href="/wiki/London_Diving_Chamber_Dive_Lectures" title="London Diving Chamber Dive Lectures">London Diving Chamber Dive Lectures</a></li> <li><a href="/wiki/NOGI_Awards" title="NOGI Awards">NOGI Awards</a></li> <li><a href="/wiki/Women_Divers_Hall_of_Fame" title="Women Divers Hall of Fame">Women Divers Hall of Fame</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Incidents</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Dive_boat" title="Dive boat">Dive boat</a> incidents</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Sinking_of_MV_Conception" title="Sinking of MV Conception">Sinking of MV <i>Conception</i></a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Diver rescues</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Alpazat_cave_rescue" title="Alpazat cave rescue">Alpazat cave rescue</a></li> <li><a href="/wiki/Tham_Luang_cave_rescue" title="Tham Luang cave rescue">Tham Luang cave rescue</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Early diving</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/John_Day_(carpenter)" title="John Day (carpenter)">John Day (carpenter)</a></li> <li><a href="/wiki/Charles_Spalding" title="Charles Spalding">Charles Spalding</a></li> <li><a href="/wiki/Ebenezer_Watson" class="mw-redirect" title="Ebenezer Watson">Ebenezer Watson</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Freediving" title="Freediving">Freediving</a> fatalities</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Stephen_Keenan" title="Stephen Keenan">Stephen Keenan</a></li> <li><a href="/wiki/Lo%C3%AFc_Leferme" title="Loïc Leferme">Loïc Leferme</a></li> <li><a href="/wiki/Audrey_Mestre" title="Audrey Mestre">Audrey Mestre</a></li> <li><a href="/wiki/Nicholas_Mevoli" title="Nicholas Mevoli">Nicholas Mevoli</a></li> <li><a href="/wiki/Natalia_Molchanova" title="Natalia Molchanova">Natalia Molchanova</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Offshore_diving" class="mw-redirect" title="Offshore diving">Offshore<br />diving</a> incidents</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Byford_Dolphin#Diving_bell_accident" title="Byford Dolphin"><i>Byford Dolphin</i> diving bell accident</a></li> <li><a href="/wiki/Drill_Master_diving_accident" title="Drill Master diving accident"><i>Drill Master</i> diving accident</a></li> <li><a href="/wiki/Star_Canopus_diving_accident" title="Star Canopus diving accident"><i>Star Canopus</i> diving accident</a></li> <li><a href="/wiki/Stena_Seaspread_diving_accident" title="Stena Seaspread diving accident"><i>Stena Seaspread</i> diving accident</a></li> <li><a href="/wiki/Venture_One_diving_accident" class="mw-redirect" title="Venture One diving accident"><i>Venture One</i> diving accident</a></li> <li><a href="/wiki/Waage_Drill_II_diving_accident" title="Waage Drill II diving accident"><i>Waage Drill II</i> diving accident</a></li> <li><a href="/wiki/Wildrake_diving_accident" title="Wildrake diving accident"><i>Wildrake</i> diving accident</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Professional_diving" title="Professional diving">Professional<br />diving</a> fatalities</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Roger_Baldwin_(diver)" class="mw-redirect" title="Roger Baldwin (diver)">Roger Baldwin</a></li> <li><a href="/wiki/John_Bennett_(diver)" title="John Bennett (diver)">John Bennett</a></li> <li><a href="/wiki/Victor_F._Guiel_Jr." class="mw-redirect" title="Victor F. Guiel Jr.">Victor F. Guiel Jr.</a></li> <li><a href="/wiki/Francis_P._Hammerberg" title="Francis P. Hammerberg">Francis P. Hammerberg</a></li> <li><a href="/wiki/Craig_M._Hoffman" class="mw-redirect" title="Craig M. Hoffman">Craig M. Hoffman</a></li> <li><a href="/wiki/Peter_Henry_Michael_Holmes" class="mw-redirect" title="Peter Henry Michael Holmes">Peter Henry Michael Holmes</a></li> <li><a href="/wiki/Johnson_Sea_Link_accident" title="Johnson Sea Link accident">Johnson Sea Link accident</a> <ul><li><a href="/wiki/Edwin_Clayton_Link" class="mw-redirect" title="Edwin Clayton Link">Edwin Clayton Link</a></li></ul></li> <li><a href="/wiki/Gerard_Anthony_Prangley" class="mw-redirect" title="Gerard Anthony Prangley">Gerard Anthony Prangley</a></li> <li><a href="/wiki/Per_Skipnes" class="mw-redirect" title="Per Skipnes">Per Skipnes</a></li> <li><a href="/wiki/Robert_John_Smyth" class="mw-redirect" title="Robert John Smyth">Robert John Smyth</a></li> <li><a href="/wiki/Albert_D._Stover" class="mw-redirect" title="Albert D. Stover">Albert D. Stover</a></li> <li><a href="/wiki/Richard_A._Walker" class="mw-redirect" title="Richard A. Walker">Richard A. Walker</a></li> <li><a href="/wiki/Lothar_Michael_Ward" class="mw-redirect" title="Lothar Michael Ward">Lothar Michael Ward</a></li> <li><a href="/wiki/Joachim_Wendler" title="Joachim Wendler">Joachim Wendler</a></li> <li><a href="/wiki/Death_of_Bradley_Westell" title="Death of Bradley Westell">Bradley Westell</a></li> <li><a href="/wiki/Arne_Zetterstr%C3%B6m" title="Arne Zetterström">Arne Zetterström</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Scuba_diving_fatalities" title="Scuba diving fatalities">Scuba diving<br />fatalities</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/1973_Mount_Gambier_cave_diving_accident" title="1973 Mount Gambier cave diving accident">1973 Mount Gambier cave diving accident</a></li> <li><a href="/wiki/Ricardo_Armbruster" title="Ricardo Armbruster">Ricardo Armbruster</a></li> <li><a href="/wiki/Allan_Bridge" title="Allan Bridge">Allan Bridge</a></li> <li><a href="/wiki/David_Bright_(diver)" title="David Bright (diver)">David Bright</a></li> <li><a href="/wiki/Berry_L._Cannon" title="Berry L. Cannon">Berry L. Cannon</a></li> <li><a href="/wiki/Cotton_Coulson" title="Cotton Coulson">Cotton Coulson</a></li> <li><a href="/wiki/Cl%C3%A1udio_Coutinho" title="Cláudio Coutinho">Cláudio Coutinho</a></li> <li><a href="/wiki/E._Yale_Dawson" title="E. Yale Dawson">E. Yale Dawson</a></li> <li><a href="/wiki/Deon_Dreyer" title="Deon Dreyer">Deon Dreyer</a></li> <li><a href="/wiki/Milan_Dufek" title="Milan Dufek">Milan Dufek</a></li> <li><a href="/wiki/Sheck_Exley" title="Sheck Exley">Sheck Exley</a></li> <li><a href="/wiki/Maurice_Fargues" title="Maurice Fargues">Maurice Fargues</a></li> <li><a href="/wiki/Fernando_Garfella_Palmer" title="Fernando Garfella Palmer">Fernando Garfella Palmer</a></li> <li><a href="/wiki/Guy_Garman" title="Guy Garman">Guy Garman</a></li> <li><a href="/wiki/Steve_Irwin" title="Steve Irwin">Steve Irwin</a> <ul><li><a href="/wiki/Death_of_Steve_Irwin" title="Death of Steve Irwin">death</a></li></ul></li> <li><a href="/wiki/Jim_Jones_(American_football,_born_1935)" title="Jim Jones (American football, born 1935)">Jim Jones</a></li> <li><a href="/wiki/Henry_Way_Kendall" title="Henry Way Kendall">Henry Way Kendall</a></li> <li><a href="/wiki/Artur_Koz%C5%82owski_(speleologist)" title="Artur Kozłowski (speleologist)">Artur Kozłowski</a></li> <li><a href="/wiki/Yuri_Lipski" class="mw-redirect" title="Yuri Lipski">Yuri Lipski</a></li> <li><a href="/wiki/Kirsty_MacColl" title="Kirsty MacColl">Kirsty MacColl</a></li> <li><a href="/wiki/Death_of_Linnea_Mills" title="Death of Linnea Mills">Linnea Mills</a></li> <li><a href="/wiki/Agnes_Milowka" title="Agnes Milowka">Agnes Milowka</a></li> <li><a href="/wiki/Fran%C3%A7ois_de_Roubaix" title="François de Roubaix">François de Roubaix</a></li> <li><a href="/wiki/The_Last_Dive" title="The Last Dive">Chris and Chrissy Rouse</a></li> <li><a href="/wiki/Dave_Shaw" title="Dave Shaw">Dave Shaw</a></li> <li><a href="/wiki/Wesley_C._Skiles" title="Wesley C. Skiles">Wesley C. Skiles</a></li> <li><a href="/wiki/Dewey_Smith" title="Dewey Smith">Dewey Smith</a></li> <li><a href="/wiki/Rob_Stewart_(filmmaker)" title="Rob Stewart (filmmaker)">Rob Stewart</a></li> <li><a href="/wiki/Esbj%C3%B6rn_Svensson" title="Esbjörn Svensson">Esbjörn Svensson</a></li> <li><a href="/wiki/Josef_Velek" title="Josef Velek">Josef Velek</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr></tbody></table><div> </div></td></tr></tbody></table><div></div></td></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks mw-collapsible mw-collapsed navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><div id="Publications" style="font-size:114%;margin:0 4em">Publications</div></th></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">Manuals</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><i><a href="/wiki/NOAA_Diving_Manual" title="NOAA Diving Manual">NOAA Diving Manual</a></i></li> <li><i><a href="/wiki/U.S._Navy_Diving_Manual" title="U.S. Navy Diving Manual">U.S. Navy Diving Manual</a></i></li> <li><i><a href="/wiki/Basic_Cave_Diving:_A_Blueprint_for_Survival" title="Basic Cave Diving: A Blueprint for Survival">Basic Cave Diving: A Blueprint for Survival</a></i></li> <li><i><a href="/w/index.php?title=Underwater_Handbook&action=edit&redlink=1" class="new" title="Underwater Handbook (page does not exist)">Underwater Handbook</a></i></li> <li><i><a href="/w/index.php?title=Bennett_and_Elliott%27s_physiology_and_medicine_of_diving&action=edit&redlink=1" class="new" title="Bennett and Elliott's physiology and medicine of diving (page does not exist)">Bennett and Elliott's physiology and medicine of diving</a></i></li> <li><i><a href="/w/index.php?title=Encyclopedia_of_Recreational_Diving&action=edit&redlink=1" class="new" title="Encyclopedia of Recreational Diving (page does not exist)">Encyclopedia of Recreational Diving</a></i></li> <li><i><a href="/w/index.php?title=The_new_science_of_skin_and_scuba_diving&action=edit&redlink=1" class="new" title="The new science of skin and scuba diving (page does not exist)">The new science of skin and scuba diving</a></i></li> <li><i><a href="/w/index.php?title=Professional_Diver%27s_Handbook&action=edit&redlink=1" class="new" title="Professional Diver's Handbook (page does not exist)">Professional Diver's Handbook</a></i></li> <li><i><a href="/w/index.php?title=Basic_Scuba&action=edit&redlink=1" class="new" title="Basic Scuba (page does not exist)">Basic Scuba</a></i></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Standards and<br />Codes of Practice</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Code_of_Practice_for_Scientific_Diving_(UNESCO)" class="mw-redirect" title="Code of Practice for Scientific Diving (UNESCO)">Code of Practice for Scientific Diving (UNESCO)</a></li> <li><a href="/wiki/DIN_7876" title="DIN 7876">DIN 7876</a></li> <li><a href="/wiki/IMCA_Code_of_Practice_for_Offshore_Diving" class="mw-redirect" title="IMCA Code of Practice for Offshore Diving">IMCA Code of Practice for Offshore Diving</a></li> <li><a href="/wiki/ISO_24801_Recreational_diving_services_%E2%80%94_Requirements_for_the_training_of_recreational_scuba_divers" class="mw-redirect" title="ISO 24801 Recreational diving services — Requirements for the training of recreational scuba divers">ISO 24801 Recreational diving services — Requirements for the training of recreational scuba divers</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">General non-fiction</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><i><a href="/wiki/The_Darkness_Beckons" title="The Darkness Beckons">The Darkness Beckons</a></i></li> <li><i><a href="/wiki/Goldfinder" title="Goldfinder">Goldfinder</a></i></li> <li><i><a href="/wiki/The_Last_Dive" title="The Last Dive">The Last Dive</a></i></li> <li><i><a href="/wiki/Shadow_Divers" title="Shadow Divers">Shadow Divers</a></i></li> <li><i><a href="/wiki/The_Silent_World:_A_Story_of_Undersea_Discovery_and_Adventure" title="The Silent World: A Story of Undersea Discovery and Adventure">The Silent World: A Story of Undersea Discovery and Adventure</a></i></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Research</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/List_of_Divers_Alert_Network_publications" title="List of Divers Alert Network publications">List of Divers Alert Network publications</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Dive_guide_(publication)" class="mw-redirect" title="Dive guide (publication)">Dive guides</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li class="mw-empty-elt"></li></ul> </div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks mw-collapsible mw-collapsed navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><div id="Training_and_registration" style="font-size:114%;margin:0 4em">Training and registration</div></th></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Diver_training" title="Diver training">Diver<br />training</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li>Competence and assessment <ul><li><a href="/wiki/Competency-based_learning" title="Competency-based learning">Competency-based learning</a></li> <li><a href="/wiki/Refresher_training_(diving)" class="mw-redirect" title="Refresher training (diving)">Refresher training</a></li> <li><a href="/wiki/Skill_assessment" title="Skill assessment">Skill assessment</a></li></ul></li> <li><a href="/wiki/Diver_training_standard" title="Diver training standard">Diver training standard</a></li> <li><a href="/wiki/Diving_instructor" title="Diving instructor">Diving instructor</a></li> <li><a href="/wiki/Diving_school" class="mw-redirect" title="Diving school">Diving school</a></li> <li>Occupational diver training <ul><li><a href="/wiki/Commercial_diver_training" class="mw-redirect" title="Commercial diver training">Commercial diver training</a></li> <li><a href="/wiki/Military_diver_training" class="mw-redirect" title="Military diver training">Military diver training</a></li> <li><a href="/wiki/Public_safety_diver_training" class="mw-redirect" title="Public safety diver training">Public safety diver training</a></li> <li><a href="/wiki/Scientific_diver_training" class="mw-redirect" title="Scientific diver training">Scientific diver training</a></li></ul></li> <li><a href="/wiki/Recreational_diver_training" title="Recreational diver training">Recreational diver training</a> <ul><li><a href="/wiki/Introductory_diving" title="Introductory diving">Introductory diving</a></li> <li><a href="/wiki/ISO_recreational_diving_training_standards" class="mw-redirect" title="ISO recreational diving training standards">ISO training standards</a></li></ul></li> <li><a href="/wiki/Teaching_method" title="Teaching method">Teaching method</a> <ul><li><a href="/wiki/Muscle_memory" title="Muscle memory">Muscle memory</a></li> <li><a href="/wiki/Overlearning" title="Overlearning">Overlearning</a></li> <li><a href="/wiki/Stress_exposure_training" title="Stress exposure training">Stress exposure training</a></li></ul></li></ul> </div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="Skills" scope="row" class="navbox-group" style="width:1%">Skills</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Combat_sidestroke" title="Combat sidestroke">Combat sidestroke</a></li> <li><a href="/wiki/Diver_navigation" title="Diver navigation">Diver navigation</a></li> <li><a href="/wiki/Diver_trim" title="Diver trim">Diver trim</a></li> <li><a href="/wiki/Ear_clearing" title="Ear clearing">Ear clearing</a> <ul><li><a href="/wiki/Frenzel_maneuver" title="Frenzel maneuver">Frenzel maneuver</a></li> <li><a href="/wiki/Valsalva_maneuver" title="Valsalva maneuver">Valsalva maneuver</a></li></ul></li> <li><a href="/wiki/Finning_techniques" title="Finning techniques">Finning techniques</a></li> <li><a href="/wiki/Scuba_skills" title="Scuba skills">Scuba skills</a> <ul><li><a href="/wiki/Buddy_breathing" title="Buddy breathing">Buddy breathing</a></li> <li><a href="/wiki/Low_impact_diving" title="Low impact diving">Low impact diving</a> <ul><li><a href="/wiki/Diamond_Reef_System" title="Diamond Reef System">Diamond Reef System</a></li></ul></li></ul></li> <li><a href="/wiki/Surface-supplied_diving_skills" title="Surface-supplied diving skills">Surface-supplied diving skills</a></li> <li><a href="/wiki/Underwater_searches" title="Underwater searches">Underwater searches</a></li></ul> </div></td></tr></tbody></table><div> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Recreational_scuba_certification_levels" title="Recreational scuba certification levels">Recreational<br />scuba<br />certification<br />levels</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">Core diving skills</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Advanced_Open_Water_Diver" title="Advanced Open Water Diver">Advanced Open Water Diver</a></li> <li><a href="/wiki/Autonomous_diver" title="Autonomous diver">Autonomous diver</a></li> <li><a href="/wiki/CMAS*_scuba_diver" title="CMAS* scuba diver">CMAS* scuba diver</a></li> <li><a href="/wiki/CMAS**_scuba_diver" title="CMAS** scuba diver">CMAS** scuba diver</a></li> <li><a href="/wiki/Introductory_diving" title="Introductory diving">Introductory diving</a></li> <li><a href="/wiki/Low_Impact_Diver" class="mw-redirect" title="Low Impact Diver">Low Impact Diver</a></li> <li><a href="/wiki/Master_Scuba_Diver" title="Master Scuba Diver">Master Scuba Diver</a></li> <li><a href="/wiki/Open_Water_Diver" title="Open Water Diver">Open Water Diver</a></li> <li><a href="/wiki/Supervised_diver" title="Supervised diver">Supervised diver</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Leadership skills</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Dive_leader" title="Dive leader">Dive leader</a> <ul><li><a href="/wiki/Divemaster" title="Divemaster">Divemaster</a></li></ul></li> <li><a href="/wiki/Diving_instructor" title="Diving instructor">Diving instructor</a> <ul><li><a href="/wiki/Master_Instructor" class="mw-redirect" title="Master Instructor">Master Instructor</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Specialist skills</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Rescue_Diver" title="Rescue Diver">Rescue Diver</a></li> <li><a href="/wiki/Solo_diver" class="mw-redirect" title="Solo diver">Solo diver</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Diver_training_organization" title="Diver training organization">Diver training<br />certification<br />and registration<br />organisations</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/European_Underwater_Federation" title="European Underwater Federation">European Underwater Federation</a> (EUF)</li> <li><a href="/wiki/International_Diving_Regulators_and_Certifiers_Forum" title="International Diving Regulators and Certifiers Forum">International Diving Regulators and Certifiers Forum</a> (IDRCF)</li> <li><a href="/wiki/International_Diving_Schools_Association" title="International Diving Schools Association">International Diving Schools Association</a> (IDSA)</li> <li><a href="/wiki/International_Marine_Contractors_Association" title="International Marine Contractors Association">International Marine Contractors Association</a> (IMCA)</li> <li><a href="/wiki/List_of_diver_certification_organizations" title="List of diver certification organizations">List of diver certification organizations</a></li> <li><a href="/wiki/National_Oceanic_and_Atmospheric_Administration" title="National Oceanic and Atmospheric Administration">National Oceanic and Atmospheric Administration</a> (NOAA)</li> <li><a href="/wiki/Nautical_Archaeology_Society" title="Nautical Archaeology Society">Nautical Archaeology Society</a></li> <li><a href="/wiki/Recreational_diver_course_referral" title="Recreational diver course referral">Recreational diver course referral</a></li> <li><a href="/wiki/World_Recreational_Scuba_Training_Council" title="World Recreational Scuba Training Council">World Recreational Scuba Training Council</a> (WRSTC)</li></ul> </div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">Commercial diver<br />certification<br />authorities</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Australian_Diver_Accreditation_Scheme" title="Australian Diver Accreditation Scheme">Australian Diver Accreditation Scheme</a> (ADAS)</li> <li><a href="/wiki/Commercial_diver_registration_in_South_Africa" title="Commercial diver registration in South Africa">Commercial diver registration in South Africa</a></li> <li><a href="/wiki/Divers_Institute_of_Technology" title="Divers Institute of Technology">Divers Institute of Technology</a></li> <li><a href="/wiki/Health_and_Safety_Executive" title="Health and Safety Executive">Health and Safety Executive</a> (HSE)</li> <li><a href="/wiki/Department_of_Employment_and_Labour" title="Department of Employment and Labour">Department of Employment and Labour</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Commercial diving<br />schools</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Divers_Academy_International" title="Divers Academy International">Divers Academy International</a></li> <li><a href="/wiki/Western_Norway_University_of_Applied_Sciences#Norwegian_diver_school" title="Western Norway University of Applied Sciences">Norwegian diver school</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Free-diving<br />certification<br />agencies</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/AIDA_International" title="AIDA International">AIDA International</a> (AIDA)</li> <li><a href="/wiki/Conf%C3%A9d%C3%A9ration_Mondiale_des_Activit%C3%A9s_Subaquatiques" title="Confédération Mondiale des Activités Subaquatiques">Confédération Mondiale des Activités Subaquatiques</a> (CMAS)</li> <li><a href="/wiki/Performance_Freediving_International" title="Performance Freediving International">Performance Freediving International</a> (PI)</li> <li><a href="/wiki/Scuba_Schools_International" title="Scuba Schools International">Scuba Schools International</a> (SSI)</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Recreational<br />scuba<br />certification<br />agencies</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/American_Canadian_Underwater_Certifications" title="American Canadian Underwater Certifications">American Canadian Underwater Certifications</a> (ACUC)</li> <li><a href="/wiki/American_Nitrox_Divers_International" title="American Nitrox Divers International">American Nitrox Divers International</a> (ANDI)</li> <li><a href="/wiki/Association_nationale_des_moniteurs_de_plong%C3%A9e" title="Association nationale des moniteurs de plongée">Association nationale des moniteurs de plongée</a> (ANMP)</li> <li><a href="/wiki/British_Sub-Aqua_Club" title="British Sub-Aqua Club">British Sub-Aqua Club</a> (BSAC)</li> <li><a href="/wiki/Comhairle_Fo-Thuinn" title="Comhairle Fo-Thuinn">Comhairle Fo-Thuinn</a> (CFT)</li> <li><a href="/wiki/Conf%C3%A9d%C3%A9ration_Mondiale_des_Activit%C3%A9s_Subaquatiques" title="Confédération Mondiale des Activités Subaquatiques">Confédération Mondiale des Activités Subaquatiques</a> (CMAS)</li> <li><a href="/wiki/Federaci%C3%B3n_Espa%C3%B1ola_de_Actividades_Subacu%C3%A1ticas" title="Federación Española de Actividades Subacuáticas">Federación Española de Actividades Subacuáticas</a> (FEDAS)</li> <li><a href="/wiki/F%C3%A9d%C3%A9ration_Fran%C3%A7aise_d%27%C3%89tudes_et_de_Sports_Sous-Marins" title="Fédération Française d'Études et de Sports Sous-Marins">Fédération Française d'Études et de Sports Sous-Marins</a> (FFESSM)</li> <li><a href="/wiki/Federazione_Italiana_Attivit%C3%A0_Subacquee" title="Federazione Italiana Attività Subacquee">Federazione Italiana Attività Subacquee</a> (FIAS)</li> <li><a href="/wiki/Global_Underwater_Explorers" title="Global Underwater Explorers">Global Underwater Explorers</a> (GUE)</li> <li><a href="/wiki/International_Association_for_Handicapped_Divers" title="International Association for Handicapped Divers">International Association for Handicapped Divers</a> (IAHD)</li> <li><a href="/wiki/International_Association_of_Nitrox_and_Technical_Divers" title="International Association of Nitrox and Technical Divers">International Association of Nitrox and Technical Divers</a> (IANTD)</li> <li><a href="/wiki/International_Life_Saving_Federation" title="International Life Saving Federation">International Life Saving Federation</a> (ILS)</li> <li><a href="/wiki/Israeli_Diving_Federation" title="Israeli Diving Federation">Israeli Diving Federation</a> (TIDF)</li> <li><a href="/wiki/National_Academy_of_Scuba_Educators" title="National Academy of Scuba Educators">National Academy of Scuba Educators</a> (NASE)</li> <li><a href="/wiki/National_Association_of_Underwater_Instructors" title="National Association of Underwater Instructors">National Association of Underwater Instructors</a> (NAUI)</li> <li><a href="/wiki/Nederlandse_Onderwatersport_Bond" title="Nederlandse Onderwatersport Bond">Nederlandse Onderwatersport Bond</a> (NOB)</li> <li><a href="/wiki/Professional_Association_of_Diving_Instructors" title="Professional Association of Diving Instructors">Professional Association of Diving Instructors</a> (PADI)</li> <li><a href="/wiki/Professional_Diving_Instructors_Corporation" title="Professional Diving Instructors Corporation">Professional Diving Instructors Corporation</a> (PDIC)</li> <li><a href="/wiki/Professional_Technical_and_Recreational_Diving" title="Professional Technical and Recreational Diving">Professional Technical and Recreational Diving</a> (ProTec)</li> <li><a href="/wiki/Rebreather_Association_of_International_Divers" title="Rebreather Association of International Divers">Rebreather Association of International Divers</a> (RAID)</li> <li><a href="/wiki/Sub-Aqua_Association" title="Sub-Aqua Association">Sub-Aqua Association</a> (SAA)</li> <li><a href="/wiki/Scuba_Diving_International" title="Scuba Diving International">Scuba Diving International</a> (SDI)</li> <li><a href="/wiki/Scuba_Educators_International" title="Scuba Educators International">Scuba Educators International</a> (SEI)</li> <li><a href="/wiki/Scottish_Sub_Aqua_Club" title="Scottish Sub Aqua Club">Scottish Sub Aqua Club</a> (ScotSAC)</li> <li><a href="/wiki/Scuba_Schools_International" title="Scuba Schools International">Scuba Schools International</a> (SSI)</li> <li><a href="/wiki/Turkish_Underwater_Sports_Federation" title="Turkish Underwater Sports Federation">Türkiye Sualtı Sporları Federasyonu</a> (TSSF)</li> <li><a href="/wiki/United_Diving_Instructors" title="United Diving Instructors">United Diving Instructors</a> (UDI)</li> <li><a href="/wiki/YMCA_SCUBA_Program" title="YMCA SCUBA Program">YMCA SCUBA Program</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Scientific diver<br />certification<br />authorities</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/American_Academy_of_Underwater_Sciences" title="American Academy of Underwater Sciences">American Academy of Underwater Sciences</a> (AAUS)</li> <li><a href="/wiki/Conf%C3%A9d%C3%A9ration_Mondiale_des_Activit%C3%A9s_Subaquatiques#Scientific_committee" title="Confédération Mondiale des Activités Subaquatiques">CMAS Scientific Committee</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Technical diver<br />certification<br />agencies</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/American_Nitrox_Divers_International" title="American Nitrox Divers International">American Nitrox Divers International</a> (ANDI)</li> <li><a href="/wiki/British_Sub-Aqua_Club" title="British Sub-Aqua Club">British Sub-Aqua Club</a> (BSAC)</li> <li><a href="/wiki/Conf%C3%A9d%C3%A9ration_Mondiale_des_Activit%C3%A9s_Subaquatiques" title="Confédération Mondiale des Activités Subaquatiques">Confédération Mondiale des Activités Subaquatiques</a> (CMAS)</li> <li><a href="/wiki/Diving_Science_and_Technology" title="Diving Science and Technology">Diving Science and Technology</a> (DSAT)</li> <li><a href="/wiki/Federazione_Italiana_Attivit%C3%A0_Subacquee" title="Federazione Italiana Attività Subacquee">Federazione Italiana Attività Subacquee</a> (FIAS)</li> <li><a href="/wiki/International_Association_of_Nitrox_and_Technical_Divers" title="International Association of Nitrox and Technical Divers">International Association of Nitrox and Technical Divers</a> (IANTD)</li> <li><a href="/wiki/Professional_Association_of_Diving_Instructors" title="Professional Association of Diving Instructors">Professional Association of Diving Instructors</a> (PADI)</li> <li><a href="/wiki/Professional_Diving_Instructors_Corporation" title="Professional Diving Instructors Corporation">Professional Diving Instructors Corporation</a> (PDIC)</li> <li><a href="/wiki/Professional_Technical_and_Recreational_Diving" title="Professional Technical and Recreational Diving">Professional Technical and Recreational Diving</a> (ProTec)</li> <li><a href="/wiki/Rebreather_Association_of_International_Divers" title="Rebreather Association of International Divers">Rebreather Association of International Divers</a> (RAID)</li> <li><a href="/wiki/Trimix_Scuba_Association" title="Trimix Scuba Association">Trimix Scuba Association</a> (TSA)</li> <li><a href="/wiki/Scuba_Schools_International" title="Scuba Schools International">Technical Extended Range</a> (TXR)</li></ul> </div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="Cavediving" scope="row" class="navbox-group" style="width:1%">Cave<br />diving</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Cave_Divers_Association_of_Australia" title="Cave Divers Association of Australia">Cave Divers Association of Australia</a> (CDAA)</li> <li><a href="/wiki/Cave_Diving_Group" title="Cave Diving Group">Cave Diving Group</a> (CDG)</li> <li><a href="/wiki/Global_Underwater_Explorers" title="Global Underwater Explorers">Global Underwater Explorers</a> (GUE)</li> <li><a href="/wiki/National_Speleological_Society#Cave_Diving_Group" title="National Speleological Society">National Speleological Society#Cave Diving Group</a> (CDG)</li> <li><a href="/wiki/National_Association_of_Underwater_Instructors" title="National Association of Underwater Instructors">National Association of Underwater Instructors</a> (NAUI)</li> <li><a href="/wiki/Technical_Diving_International" title="Technical Diving International">Technical Diving International</a> (TDI)</li></ul> </div></td></tr></tbody></table><div> </div></td></tr></tbody></table><div> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Military diver<br />training centres</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Defence_Diving_School" title="Defence Diving School">Defence Diving School</a></li> <li><a href="/wiki/Naval_Support_Activity_Panama_City#Tenant_commands" title="Naval Support Activity Panama City">Navy Diving Salvage and Training Center</a></li> <li><a href="/wiki/Underwater_Escape_Training_Unit" title="Underwater Escape Training Unit">Underwater Escape Training Unit</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Military diver<br />training courses</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/United_States_Marine_Corps_Combatant_Diver_Course" title="United States Marine Corps Combatant Diver Course">United States Marine Corps Combatant Diver Course</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks mw-collapsible mw-collapsed navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><div id="Underwater_sports" style="font-size:114%;margin:0 4em"><a href="/wiki/Underwater_sports" title="Underwater sports">Underwater sports</a></div></th></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">Surface snorkeling</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Finswimming" title="Finswimming">Finswimming</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Snorkeling/breath-hold</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Spearfishing" title="Spearfishing">Spearfishing</a></li> <li><a href="/wiki/Underwater_football" title="Underwater football">Underwater football</a></li> <li><a href="/wiki/Underwater_hockey" title="Underwater hockey">Underwater hockey</a> <ul><li><a href="/wiki/Underwater_hockey_in_Australia" title="Underwater hockey in Australia">Australia</a></li> <li><a href="/wiki/Underwater_hockey_in_Turkey" title="Underwater hockey in Turkey">Turkey</a></li></ul></li> <li><a href="/wiki/Underwater_rugby" title="Underwater rugby">Underwater rugby</a> <ul><li><a href="/wiki/Underwater_rugby_in_Colombia" class="mw-redirect" title="Underwater rugby in Colombia">Colombia</a></li> <li><a href="/wiki/Underwater_rugby_in_the_United_States" title="Underwater rugby in the United States">United States</a></li></ul></li> <li><a href="/wiki/Underwater_target_shooting" title="Underwater target shooting">Underwater target shooting</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Breath-hold</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Aquathlon_(underwater_wrestling)" title="Aquathlon (underwater wrestling)">Aquathlon</a></li> <li><a href="/wiki/Apnoea_finswimming" class="mw-redirect" title="Apnoea finswimming">Apnoea finswimming</a></li> <li><a href="/wiki/Freediving" title="Freediving">Freediving</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Open Circuit Scuba</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Immersion_finswimming" class="mw-redirect" title="Immersion finswimming">Immersion finswimming</a></li> <li><a href="/wiki/Sport_diving_(sport)" title="Sport diving (sport)">Sport diving</a></li> <li><a href="/wiki/Underwater_cycling" title="Underwater cycling">Underwater cycling</a></li> <li><a href="/wiki/Underwater_orienteering" title="Underwater orienteering">Underwater orienteering</a></li> <li><a href="/wiki/Underwater_photography_(sport)" title="Underwater photography (sport)">Underwater photography</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Rebreather</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Underwater_photography_(sport)" title="Underwater photography (sport)">Underwater photography</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Sports governing<br />organisations<br /> and federations</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li>International <ul><li><a href="/wiki/AIDA_International" title="AIDA International">AIDA International</a></li> <li><a href="/wiki/Conf%C3%A9d%C3%A9ration_Mondiale_des_Activit%C3%A9s_Subaquatiques" title="Confédération Mondiale des Activités Subaquatiques">Confédération Mondiale des Activités Subaquatiques</a>)</li></ul></li> <li>National <ul><li><a href="/wiki/AIDA_Hellas" title="AIDA Hellas">AIDA Hellas</a></li> <li><a href="/wiki/Australian_Underwater_Federation" title="Australian Underwater Federation">Australian Underwater Federation</a></li> <li><a href="/wiki/British_Freediving_Association" title="British Freediving Association">British Freediving Association</a></li> <li><a href="/wiki/British_Octopush_Association" title="British Octopush Association">British Octopush Association</a></li> <li><a href="/wiki/British_Underwater_Sports_Association" title="British Underwater Sports Association">British Underwater Sports Association</a></li> <li><a href="/wiki/Comhairle_Fo-Thuinn" title="Comhairle Fo-Thuinn">Comhairle Fo-Thuinn</a></li> <li><a href="/wiki/Federaci%C3%B3n_Espa%C3%B1ola_de_Actividades_Subacu%C3%A1ticas" title="Federación Española de Actividades Subacuáticas">Federación Española de Actividades Subacuáticas</a></li> <li><a href="/wiki/French_federation_of_underwater_studies_and_sports" class="mw-redirect" title="French federation of underwater studies and sports">Fédération Française d'Études et de Sports Sous-Marins</a></li> <li><a href="/wiki/South_African_Underwater_Sports_Federation" title="South African Underwater Sports Federation">South African Underwater Sports Federation</a></li> <li><a href="/wiki/Turkish_Underwater_Sports_Federation" title="Turkish Underwater Sports Federation">Türkiye Sualtı Sporları Federasyonu</a></li> <li><a href="/wiki/Underwater_Society_of_America" title="Underwater Society of America">Underwater Society of America</a>)</li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Competitions</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/14th_CMAS_Underwater_Photography_World_Championship" title="14th CMAS Underwater Photography World Championship">14th CMAS Underwater Photography World Championship</a></li> <li><a href="/wiki/Underwater_Hockey_World_Championships" title="Underwater Hockey World Championships">Underwater Hockey World Championships</a></li> <li><a href="/wiki/Underwater_Orienteering_World_Championships" title="Underwater Orienteering World Championships">Underwater Orienteering World Championships</a></li> <li><a href="/wiki/Underwater_Rugby_World_Championships" title="Underwater Rugby World Championships">Underwater Rugby World Championships</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks mw-collapsible mw-collapsed navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><div id="Underwater_divers" style="font-size:114%;margin:0 4em"><a href="/wiki/Outline_of_underwater_divers" title="Outline of underwater divers">Underwater divers</a></div></th></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">Pioneers<br />of diving</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Eduard_Admetlla_i_L%C3%A1zaro" title="Eduard Admetlla i Lázaro">Eduard Admetlla i Lázaro</a></li> <li><a href="/wiki/Aquanaut" title="Aquanaut">Aquanaut</a></li> <li><a href="/wiki/Mary_Bonnin" title="Mary Bonnin">Mary Bonnin</a></li> <li><a href="/wiki/Amelia_Behrens-Furniss" title="Amelia Behrens-Furniss">Amelia Behrens-Furniss</a></li> <li><a href="/wiki/James_F._Cahill" title="James F. Cahill">James F. Cahill</a></li> <li><a href="/wiki/Jacques_Cousteau" title="Jacques Cousteau">Jacques Cousteau</a></li> <li><a href="/wiki/Billy_Deans_(diver)" title="Billy Deans (diver)">Billy Deans</a></li> <li><a href="/wiki/Dottie_Frazier" title="Dottie Frazier">Dottie Frazier</a></li> <li><a href="/wiki/Trevor_Hampton" title="Trevor Hampton">Trevor Hampton</a></li> <li><a href="/wiki/Hans_Hass" title="Hans Hass">Hans Hass</a></li> <li><a href="/wiki/Dick_Rutkowski" title="Dick Rutkowski">Dick Rutkowski</a></li> <li><a href="/wiki/Teseo_Tesei" title="Teseo Tesei">Teseo Tesei</a></li> <li><a href="/wiki/Arne_Zetterstr%C3%B6m" title="Arne Zetterström">Arne Zetterström</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Underwater<br />scientists<br />archaeologists and<br />environmentalists</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Michael_Arbuthnot" title="Michael Arbuthnot">Michael Arbuthnot</a></li> <li><a href="/wiki/Robert_Ballard" title="Robert Ballard">Robert Ballard</a></li> <li><a href="/wiki/George_Bass_(archaeologist)" title="George Bass (archaeologist)">George Bass</a></li> <li><a href="/wiki/Mensun_Bound" title="Mensun Bound">Mensun Bound</a></li> <li><a href="/wiki/Louis_Boutan" title="Louis Boutan">Louis Boutan</a></li> <li><a href="/wiki/Jeffrey_Bozanic" title="Jeffrey Bozanic">Jeffrey Bozanic</a></li> <li><a href="/wiki/Hugh_Bradner" title="Hugh Bradner">Hugh Bradner</a></li> <li><a href="/wiki/Cathy_Church" title="Cathy Church">Cathy Church</a></li> <li><a href="/wiki/Eugenie_Clark" title="Eugenie Clark">Eugenie Clark</a></li> <li><a href="/wiki/James_P._Delgado" title="James P. Delgado">James P. Delgado</a></li> <li><a href="/wiki/Sylvia_Earle" title="Sylvia Earle">Sylvia Earle</a></li> <li><a href="/wiki/John_Christopher_Fine" title="John Christopher Fine">John Christopher Fine</a></li> <li><a href="/wiki/George_R._Fischer" title="George R. Fischer">George R. Fischer</a></li> <li><a href="/wiki/Anders_Franz%C3%A9n" title="Anders Franzén">Anders Franzén</a></li> <li><a href="/wiki/Honor_Frost" title="Honor Frost">Honor Frost</a></li> <li><a href="/wiki/Fernando_Garfella_Palmer" title="Fernando Garfella Palmer">Fernando Garfella Palmer</a></li> <li><a href="/wiki/David_Gibbins" title="David Gibbins">David Gibbins</a></li> <li><a href="/wiki/Graham_Jessop" title="Graham Jessop">Graham Jessop</a></li> <li><a href="/wiki/Swietenia_Puspa_Lestari" title="Swietenia Puspa Lestari">Swietenia Puspa Lestari</a></li> <li><a href="/wiki/Pilar_Luna" title="Pilar Luna">Pilar Luna</a></li> <li><a href="/wiki/Robert_F._Marx" title="Robert F. Marx">Robert F. Marx</a></li> <li><a href="/wiki/Anna_Marguerite_McCann" title="Anna Marguerite McCann">Anna Marguerite McCann</a></li> <li><a href="/wiki/Innes_McCartney" title="Innes McCartney">Innes McCartney</a></li> <li><a href="/wiki/Charles_T._Meide" title="Charles T. Meide">Charles T. Meide</a></li> <li><a href="/wiki/Mark_M._Newell" title="Mark M. Newell">Mark M. Newell</a></li> <li><a href="/wiki/Lyuba_Ognenova-Marinova" title="Lyuba Ognenova-Marinova">Lyuba Ognenova-Marinova</a></li> <li><a href="/wiki/John_Peter_Oleson" title="John Peter Oleson">John Peter Oleson</a></li> <li><a href="/wiki/Mendel_L._Peterson" title="Mendel L. Peterson">Mendel L. Peterson</a></li> <li><a href="/wiki/Richard_Pyle" title="Richard Pyle">Richard Pyle</a></li> <li><a href="/wiki/Andreas_Rechnitzer" title="Andreas Rechnitzer">Andreas Rechnitzer</a></li> <li><a href="/wiki/William_R._Royal" title="William R. Royal">William R. Royal</a></li> <li><a href="/wiki/Margaret_Rule" title="Margaret Rule">Margaret Rule</a></li> <li><a href="/wiki/Gunter_Sch%C3%B6bel" title="Gunter Schöbel">Gunter Schöbel</a></li> <li><a href="/wiki/Stephanie_Schwabe" title="Stephanie Schwabe">Stephanie Schwabe</a></li> <li><a href="/wiki/Myriam_Seco" title="Myriam Seco">Myriam Seco</a></li> <li><a href="/wiki/E._Lee_Spence" title="E. Lee Spence">E. Lee Spence</a></li> <li><a href="/wiki/Robert_St%C3%A9nuit" title="Robert Sténuit">Robert Sténuit</a></li> <li><a href="/wiki/Peter_Throckmorton" title="Peter Throckmorton">Peter Throckmorton</a></li> <li><a href="/wiki/Cristina_Zenato" title="Cristina Zenato">Cristina Zenato</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Scuba record<br />holders</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Pascal_Bernab%C3%A9" title="Pascal Bernabé">Pascal Bernabé</a></li> <li><a href="/wiki/Jim_Bowden_(diver)" title="Jim Bowden (diver)">Jim Bowden</a></li> <li><a href="/wiki/Mark_Ellyatt" title="Mark Ellyatt">Mark Ellyatt</a></li> <li><a href="/wiki/Sheck_Exley" title="Sheck Exley">Sheck Exley</a></li> <li><a href="/wiki/Nuno_Gomes_(diver)" title="Nuno Gomes (diver)">Nuno Gomes</a></li> <li><a href="/wiki/Claudia_Serpieri" title="Claudia Serpieri">Claudia Serpieri</a></li> <li><a href="/wiki/Krzysztof_Starnawski" title="Krzysztof Starnawski">Krzysztof Starnawski</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Underwater<br />filmmakers<br />and presenters</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Samir_Alhafith" title="Samir Alhafith">Samir Alhafith</a></li> <li><a href="/wiki/David_Attenborough" title="David Attenborough">David Attenborough</a></li> <li><a href="/wiki/Ram%C3%B3n_Bravo" title="Ramón Bravo">Ramón Bravo</a></li> <li><a href="/wiki/Jean-Michel_Cousteau" title="Jean-Michel Cousteau">Jean-Michel Cousteau</a></li> <li><a href="/wiki/Richie_Kohler" title="Richie Kohler">Richie Kohler</a></li> <li><a href="/wiki/Paul_Rose_(TV_presenter)" title="Paul Rose (TV presenter)">Paul Rose</a></li> <li><a href="/wiki/Andy_Torbet" title="Andy Torbet">Andy Torbet</a></li> <li><a href="/wiki/Ivan_Tors" title="Ivan Tors">Ivan Tors</a></li> <li><a href="/wiki/Andrew_Wight" title="Andrew Wight">Andrew Wight</a></li> <li><a href="/wiki/James_Cameron" title="James Cameron">James Cameron</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Underwater<br />photographers</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Doug_Allan" title="Doug Allan">Doug Allan</a></li> <li><a href="/wiki/Tamara_Benitez" title="Tamara Benitez">Tamara Benitez</a></li> <li><a href="/wiki/Georges_Beuchat" title="Georges Beuchat">Georges Beuchat</a></li> <li><a href="/wiki/Adrian_Biddle" title="Adrian Biddle">Adrian Biddle</a></li> <li><a href="/wiki/Jonathan_Bird" title="Jonathan Bird">Jonathan Bird</a></li> <li><a href="/wiki/Eric_Cheng" title="Eric Cheng">Eric Cheng</a></li> <li><a href="/wiki/Neville_Coleman" title="Neville Coleman">Neville Coleman</a></li> <li><a href="/wiki/Jacques_Cousteau" title="Jacques Cousteau">Jacques Cousteau</a></li> <li><a href="/wiki/John_D._Craig" title="John D. Craig">John D. Craig</a></li> <li><a href="/wiki/Ben_Cropp" title="Ben Cropp">Ben Cropp</a></li> <li><a href="/wiki/Bernard_Delemotte" title="Bernard Delemotte">Bernard Delemotte</a></li> <li><a href="/wiki/David_Doubilet" title="David Doubilet">David Doubilet</a></li> <li><a href="/wiki/Candice_Farmer" title="Candice Farmer">Candice Farmer</a></li> <li><a href="/wiki/John_Christopher_Fine" title="John Christopher Fine">John Christopher Fine</a></li> <li><a href="/wiki/Rodney_Fox" title="Rodney Fox">Rodney Fox</a></li> <li><a href="/wiki/Ric_Frazier" title="Ric Frazier">Ric Frazier</a></li> <li><a href="/wiki/Stephen_Frink" title="Stephen Frink">Stephen Frink</a></li> <li><a href="/wiki/Peter_Gimbel" title="Peter Gimbel">Peter Gimbel</a></li> <li><a href="/wiki/Monty_Halls" title="Monty Halls">Monty Halls</a></li> <li><a href="/wiki/Hans_Hass" title="Hans Hass">Hans Hass</a></li> <li><a href="/wiki/Henry_Way_Kendall" title="Henry Way Kendall">Henry Way Kendall</a></li> <li><a href="/wiki/Rudie_Kuiter" class="mw-redirect" title="Rudie Kuiter">Rudie Kuiter</a></li> <li><a href="/wiki/Joseph_B._MacInnis" title="Joseph B. MacInnis">Joseph B. MacInnis</a></li> <li><a href="/wiki/Luis_Marden" title="Luis Marden">Luis Marden</a></li> <li><a href="/wiki/Agnes_Milowka" title="Agnes Milowka">Agnes Milowka</a></li> <li><a href="/wiki/Noel_Monkman" title="Noel Monkman">Noel Monkman</a></li> <li><a href="/wiki/Pete_Oxford" title="Pete Oxford">Pete Oxford</a></li> <li><a href="/wiki/Steve_Parish" title="Steve Parish">Steve Parish</a></li> <li><a href="/wiki/Zale_Parry" title="Zale Parry">Zale Parry</a></li> <li><a href="/wiki/Pierre_Petit_(photographer)" title="Pierre Petit (photographer)">Pierre Petit</a></li> <li><a href="/wiki/Leni_Riefenstahl" title="Leni Riefenstahl">Leni Riefenstahl</a></li> <li><a href="/wiki/Peter_Scoones" title="Peter Scoones">Peter Scoones</a></li> <li><a href="/wiki/Brian_Skerry" title="Brian Skerry">Brian Skerry</a></li> <li><a href="/wiki/Wesley_C._Skiles" title="Wesley C. Skiles">Wesley C. Skiles</a></li> <li><a href="/wiki/E._Lee_Spence" title="E. Lee Spence">E. Lee Spence</a></li> <li><a href="/wiki/Philippe_Tailliez" title="Philippe Tailliez">Philippe Tailliez</a></li> <li><a href="/wiki/Ron_Taylor_(diver)" title="Ron Taylor (diver)">Ron Taylor</a></li> <li><a href="/wiki/Valerie_Taylor_(diver)" title="Valerie Taylor (diver)">Valerie Taylor</a></li> <li><a href="/wiki/Albert_Tillman" title="Albert Tillman">Albert Tillman</a></li> <li><a href="/wiki/John_Veltri" title="John Veltri">John Veltri</a></li> <li><a href="/wiki/Stan_Waterman" title="Stan Waterman">Stan Waterman</a></li> <li><a href="/wiki/Michele_Westmorland" title="Michele Westmorland">Michele Westmorland</a></li> <li><a href="/wiki/John_Ernest_Williamson" title="John Ernest Williamson">John Ernest Williamson</a></li> <li><a href="/wiki/J._Lamar_Worzel" title="J. Lamar Worzel">J. Lamar Worzel</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Underwater<br />explorers</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li>Caves <ul><li><a href="/wiki/Graham_Balcombe" title="Graham Balcombe">Graham Balcombe</a></li> <li><a href="/wiki/Sheck_Exley" title="Sheck Exley">Sheck Exley</a></li> <li><a href="/wiki/Martyn_Farr" title="Martyn Farr">Martyn Farr</a></li> <li><a href="/wiki/Jochen_Hasenmayer" title="Jochen Hasenmayer">Jochen Hasenmayer</a></li> <li><a href="/wiki/Jill_Heinerth" title="Jill Heinerth">Jill Heinerth</a></li> <li><a href="/wiki/Jarrod_Jablonski" title="Jarrod Jablonski">Jarrod Jablonski</a></li> <li><a href="/wiki/William_Hogarth_Main" title="William Hogarth Main">William Hogarth Main</a></li> <li><a href="/wiki/Tom_Mount" title="Tom Mount">Tom Mount</a></li> <li><a href="/wiki/Jack_Sheppard_(cave_diver)" title="Jack Sheppard (cave diver)">Jack Sheppard</a></li> <li><a href="/wiki/William_Stone_(caver)" title="William Stone (caver)">Bill Stone</a></li></ul></li> <li>Reefs <ul><li><a href="/wiki/Arthur_C._Clarke" title="Arthur C. Clarke">Arthur C. Clarke</a></li></ul></li> <li>Wrecks <ul><li><a href="/wiki/Leigh_Bishop" title="Leigh Bishop">Leigh Bishop</a></li> <li><a href="/wiki/John_Chatterton" title="John Chatterton">John Chatterton</a></li> <li><a href="/wiki/Clive_Cussler" title="Clive Cussler">Clive Cussler</a></li> <li><a href="/wiki/Bill_Nagle" title="Bill Nagle">Bill Nagle</a></li> <li><a href="/wiki/Valerie_van_Heest" title="Valerie van Heest">Valerie van Heest</a></li> <li><a href="/wiki/Aristotelis_Zervoudis" title="Aristotelis Zervoudis">Aristotelis Zervoudis</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Aquanaut" title="Aquanaut">Aquanauts</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Andrew_Abercromby" title="Andrew Abercromby">Andrew Abercromby</a></li> <li><a href="/wiki/Joseph_M._Acaba" title="Joseph M. Acaba">Joseph M. Acaba</a></li> <li><a href="/wiki/Clayton_Anderson" title="Clayton Anderson">Clayton Anderson</a></li> <li><a href="/wiki/Richard_R._Arnold" title="Richard R. Arnold">Richard R. Arnold</a></li> <li><a href="/wiki/Serena_Au%C3%B1%C3%B3n-Chancellor" title="Serena Auñón-Chancellor">Serena Auñón-Chancellor</a></li> <li><a href="/wiki/Michael_Barratt_(astronaut)" title="Michael Barratt (astronaut)">Michael Barratt (astronaut)</a></li> <li><a href="/wiki/Robert_A._Barth" title="Robert A. Barth">Robert A. Barth</a></li> <li><a href="/wiki/Bob_Behnken" title="Bob Behnken">Robert L. Behnken</a></li> <li><a href="/wiki/Randolph_Bresnik" title="Randolph Bresnik">Randolph Bresnik</a></li> <li><a href="/wiki/Timothy_J._Broderick" title="Timothy J. Broderick">Timothy J. Broderick</a></li> <li><a href="/wiki/Justin_Brown_(aquanaut)" title="Justin Brown (aquanaut)">Justin Brown</a></li> <li><a href="/wiki/Berry_L._Cannon" title="Berry L. Cannon">Berry L. Cannon</a></li> <li><a href="/wiki/Scott_Carpenter" title="Scott Carpenter">Scott Carpenter</a></li> <li><a href="/wiki/Gregory_Chamitoff" title="Gregory Chamitoff">Gregory Chamitoff</a></li> <li><a href="/wiki/Steve_Chappell" title="Steve Chappell">Steve Chappell</a></li> <li><a href="/wiki/Catherine_Coleman" title="Catherine Coleman">Catherine Coleman</a></li> <li><a href="/wiki/Robin_Cook_(American_novelist)" title="Robin Cook (American novelist)">Robin Cook</a></li> <li><a href="/wiki/Craig_B._Cooper" title="Craig B. Cooper">Craig B. Cooper</a></li> <li><a href="/wiki/Fabien_Cousteau" title="Fabien Cousteau">Fabien Cousteau</a></li> <li><a href="/wiki/Philippe_Cousteau" title="Philippe Cousteau">Philippe Cousteau</a></li> <li><a href="/wiki/Timothy_Creamer" title="Timothy Creamer">Timothy Creamer</a></li> <li><a href="/wiki/Jonathan_Dory" title="Jonathan Dory">Jonathan Dory</a></li> <li><a href="/wiki/Pedro_Duque" title="Pedro Duque">Pedro Duque</a></li> <li><a href="/wiki/Sylvia_Earle" title="Sylvia Earle">Sylvia Earle</a></li> <li><a href="/wiki/Jeanette_Epps" title="Jeanette Epps">Jeanette Epps</a></li> <li><a href="/wiki/Sheck_Exley" title="Sheck Exley">Sheck Exley</a></li> <li><a href="/wiki/Albert_Falco" title="Albert Falco">Albert Falco</a></li> <li><a href="/wiki/Andrew_J._Feustel" title="Andrew J. Feustel">Andrew J. Feustel</a></li> <li><a href="/wiki/Michael_Fincke" title="Michael Fincke">Michael Fincke</a></li> <li><a href="/wiki/Satoshi_Furukawa" title="Satoshi Furukawa">Satoshi Furukawa</a></li> <li><a href="/wiki/Ronald_J._Garan_Jr." title="Ronald J. Garan Jr.">Ronald J. Garan Jr.</a></li> <li><a href="/wiki/Michael_L._Gernhardt" title="Michael L. Gernhardt">Michael L. Gernhardt</a></li> <li><a href="/wiki/Christopher_E._Gerty" title="Christopher E. Gerty">Christopher E. Gerty</a></li> <li><a href="/wiki/David_Gruber" title="David Gruber">David Gruber</a></li> <li><a href="/wiki/Chris_Hadfield" title="Chris Hadfield">Chris Hadfield</a></li> <li><a href="/wiki/Jeremy_Hansen" title="Jeremy Hansen">Jeremy Hansen</a></li> <li><a href="/wiki/Jos%C3%A9_M._Hern%C3%A1ndez" title="José M. Hernández">José M. Hernández</a></li> <li><a href="/wiki/John_Herrington" title="John Herrington">John Herrington</a></li> <li><a href="/wiki/Paul_Hill_(flight_director)" title="Paul Hill (flight director)">Paul Hill</a></li> <li><a href="/wiki/Akihiko_Hoshide" title="Akihiko Hoshide">Akihiko Hoshide</a></li> <li><a href="/wiki/Mark_Hulsbeck" title="Mark Hulsbeck">Mark Hulsbeck</a></li> <li><a href="/wiki/Emma_Hwang" title="Emma Hwang">Emma Hwang</a></li> <li><a href="/wiki/Norishige_Kanai" title="Norishige Kanai">Norishige Kanai</a></li> <li><a href="/wiki/Les_Kaufman" title="Les Kaufman">Les Kaufman</a></li> <li><a href="/wiki/Scott_Kelly_(astronaut)" title="Scott Kelly (astronaut)">Scott Kelly</a></li> <li><a href="/wiki/Karen_Kohanowich" title="Karen Kohanowich">Karen Kohanowich</a></li> <li><a href="/wiki/Timothy_Kopra" title="Timothy Kopra">Timothy Kopra</a></li> <li><a href="/wiki/Dominic_Landucci" title="Dominic Landucci">Dominic Landucci</a></li> <li><a href="/wiki/Jon_Lindbergh" title="Jon Lindbergh">Jon Lindbergh</a></li> <li><a href="/wiki/Kjell_N._Lindgren" title="Kjell N. Lindgren">Kjell N. Lindgren</a></li> <li><a href="/wiki/Michael_L%C3%B3pez-Alegr%C3%ADa" title="Michael López-Alegría">Michael López-Alegría</a></li> <li><a href="/wiki/Joseph_B._MacInnis" title="Joseph B. MacInnis">Joseph B. MacInnis</a></li> <li><a href="/wiki/Sandra_Magnus" title="Sandra Magnus">Sandra Magnus</a></li> <li><a href="/wiki/Thomas_Marshburn" title="Thomas Marshburn">Thomas Marshburn</a></li> <li><a href="/wiki/Matthias_Maurer" title="Matthias Maurer">Matthias Maurer</a></li> <li><a href="/wiki/K._Megan_McArthur" title="K. Megan McArthur">K. Megan McArthur</a></li> <li><a href="/wiki/Craig_McKinley_(physician)" title="Craig McKinley (physician)">Craig McKinley</a></li> <li><a href="/wiki/Jessica_Meir" title="Jessica Meir">Jessica Meir</a></li> <li><a href="/wiki/Simone_Melchior" title="Simone Melchior">Simone Melchior</a></li> <li><a href="/wiki/Dorothy_Metcalf-Lindenburger" title="Dorothy Metcalf-Lindenburger">Dorothy Metcalf-Lindenburger</a></li> <li><a href="/wiki/Andreas_Mogensen" title="Andreas Mogensen">Andreas Mogensen</a></li> <li><a href="/wiki/Karen_Nyberg" title="Karen Nyberg">Karen Nyberg</a></li> <li><a href="/wiki/John_D._Olivas" title="John D. Olivas">John D. Olivas</a></li> <li><a href="/wiki/Takuya_Onishi" title="Takuya Onishi">Takuya Onishi</a></li> <li><a href="/wiki/Luca_Parmitano" title="Luca Parmitano">Luca Parmitano</a></li> <li><a href="/wiki/Nicholas_Patrick" title="Nicholas Patrick">Nicholas Patrick</a></li> <li><a href="/wiki/Tim_Peake" title="Tim Peake">Tim Peake</a></li> <li><a href="/wiki/Thomas_Pesquet" title="Thomas Pesquet">Thomas Pesquet</a></li> <li><a href="/wiki/Marc_Reagan" title="Marc Reagan">Marc Reagan</a></li> <li><a href="/wiki/Garrett_Reisman" title="Garrett Reisman">Garrett Reisman</a></li> <li><a href="/wiki/Kathleen_Rubins" title="Kathleen Rubins">Kathleen Rubins</a></li> <li><a href="/wiki/Dick_Rutkowski" title="Dick Rutkowski">Dick Rutkowski</a></li> <li><a href="/wiki/Tara_Ruttley" title="Tara Ruttley">Tara Ruttley</a></li> <li><a href="/wiki/David_Saint-Jacques" title="David Saint-Jacques">David Saint-Jacques</a></li> <li><a href="/wiki/Josef_Schmid_(flight_surgeon)" title="Josef Schmid (flight surgeon)">Josef Schmid</a></li> <li><a href="/wiki/Robert_Sheats" title="Robert Sheats">Robert Sheats</a></li> <li><a href="/wiki/Dewey_Smith" title="Dewey Smith">Dewey Smith</a></li> <li><a href="/wiki/Steve_Squyres" title="Steve Squyres">Steve Squyres</a></li> <li><a href="/wiki/Heidemarie_Stefanyshyn-Piper" title="Heidemarie Stefanyshyn-Piper">Heidemarie Stefanyshyn-Piper</a></li> <li><a href="/wiki/Robert_St%C3%A9nuit" title="Robert Sténuit">Robert Sténuit</a></li> <li><a href="/wiki/Herv%C3%A9_Stevenin" title="Hervé Stevenin">Hervé Stevenin</a></li> <li><a href="/wiki/Nicole_Stott" title="Nicole Stott">Nicole Stott</a></li> <li><a href="/wiki/James_Talacek" title="James Talacek">James Talacek</a></li> <li><a href="/wiki/Daniel_M._Tani" title="Daniel M. Tani">Daniel M. Tani</a></li> <li><a href="/wiki/Robert_Thirsk" title="Robert Thirsk">Robert Thirsk</a></li> <li><a href="/wiki/Bill_Todd" title="Bill Todd">Bill Todd</a></li> <li><a href="/wiki/Mark_T._Vande_Hei" title="Mark T. Vande Hei">Mark T. Vande Hei</a></li> <li><a href="/wiki/Koichi_Wakata" title="Koichi Wakata">Koichi Wakata</a></li> <li><a href="/wiki/Rex_J._Walheim" title="Rex J. Walheim">Rex J. Walheim</a></li> <li><a href="/wiki/Shannon_Walker" title="Shannon Walker">Shannon Walker</a></li> <li><a href="/wiki/John_Morgan_Wells" title="John Morgan Wells">John Morgan Wells</a></li> <li><a href="/wiki/Joachim_Wendler" title="Joachim Wendler">Joachim Wendler</a></li> <li><a href="/wiki/Douglas_H._Wheelock" title="Douglas H. Wheelock">Douglas H. Wheelock</a></li> <li><a href="/wiki/Peggy_Whitson" title="Peggy Whitson">Peggy Whitson</a></li> <li><a href="/wiki/Dafydd_Williams" title="Dafydd Williams">Dafydd Williams</a></li> <li><a href="/wiki/Jeffrey_Williams_(astronaut)" title="Jeffrey Williams (astronaut)">Jeffrey Williams</a></li> <li><a href="/wiki/Sunita_Williams" title="Sunita Williams">Sunita Williams</a></li> <li><a href="/wiki/Reid_Wiseman" title="Reid Wiseman">Reid Wiseman</a></li> <li><a href="/wiki/Kimiya_Yui" title="Kimiya Yui">Kimiya Yui</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Writers and journalists</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Michael_C._Barnette" title="Michael C. Barnette">Michael C. Barnette</a></li> <li><a href="/wiki/Victor_Berge" title="Victor Berge">Victor Berge</a></li> <li><a href="/wiki/Philippe_Diol%C3%A9" title="Philippe Diolé">Philippe Diolé</a></li> <li><a href="/wiki/Gary_Gentile" title="Gary Gentile">Gary Gentile</a></li> <li><a href="/wiki/Bret_Gilliam" title="Bret Gilliam">Bret Gilliam</a></li> <li><a href="/wiki/Bob_Halstead" title="Bob Halstead">Bob Halstead</a></li> <li><a href="/wiki/Hillary_Hauser" title="Hillary Hauser">Hillary Hauser</a></li> <li><a href="/wiki/Trevor_Jackson_(diver)" title="Trevor Jackson (diver)">Trevor Jackson</a></li> <li><a href="/wiki/Steve_Lewis_(diver)" title="Steve Lewis (diver)">Steve Lewis</a></li> <li><a href="/wiki/John_Mattera" title="John Mattera">John Mattera</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Rescuers</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Craig_Challen" title="Craig Challen">Craig Challen</a></li> <li><a href="/wiki/Richard_Harris_(anaesthetist)" title="Richard Harris (anaesthetist)">Richard Harris</a></li> <li><a href="/wiki/Rick_Stanton" title="Rick Stanton">Rick Stanton</a></li> <li><a href="/wiki/John_Volanthen" title="John Volanthen">John Volanthen</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Frogmen</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Lionel_Crabb" title="Lionel Crabb">Lionel Crabb</a></li> <li><a href="/wiki/Ian_Edward_Fraser" title="Ian Edward Fraser">Ian Edward Fraser</a></li> <li><a href="/wiki/Sydney_Knowles" title="Sydney Knowles">Sydney Knowles</a></li> <li><a href="/wiki/James_Joseph_Magennis" title="James Joseph Magennis">James Joseph Magennis</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Commercial salvors</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Keith_Jessop" title="Keith Jessop">Keith Jessop</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks mw-collapsible mw-collapsed navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><div id="Science_of_underwater_diving" style="font-size:114%;margin:0 4em"><a href="/wiki/Science_of_underwater_diving" title="Science of underwater diving">Science of underwater diving</a></div></th></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/List_of_researchers_in_underwater_diving" title="List of researchers in underwater diving">List of researchers in underwater diving</a></li></ul> </div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Diving_physics" title="Diving physics">Diving<br />physics</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Metre_sea_water" title="Metre sea water">Metre sea water</a></li> <li><a href="/wiki/Neutral_buoyancy" title="Neutral buoyancy">Neutral buoyancy</a></li> <li><a href="/wiki/Underwater_acoustics" title="Underwater acoustics">Underwater acoustics</a> <ul><li><a href="/wiki/Modulated_ultrasound" title="Modulated ultrasound">Modulated ultrasound</a></li></ul></li> <li><a href="/wiki/Underwater_vision" title="Underwater vision">Underwater vision</a> <ul><li><a href="/wiki/Underwater_computer_vision" title="Underwater computer vision">Underwater computer vision</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Diving_physiology" class="mw-redirect" title="Diving physiology">Diving<br />physiology</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Diving_reflex#Blood_shift" title="Diving reflex">Blood shift</a></li> <li><a href="/wiki/Cold_shock_response" title="Cold shock response">Cold shock response</a></li> <li><a href="/wiki/Diving_reflex" title="Diving reflex">Diving reflex</a></li> <li><a href="/wiki/Equivalent_narcotic_depth" title="Equivalent narcotic depth">Equivalent narcotic depth</a></li> <li><a href="/wiki/Maximum_operating_depth" title="Maximum operating depth">Maximum operating depth</a></li> <li><a href="/wiki/Physiological_response_to_water_immersion" class="mw-redirect" title="Physiological response to water immersion">Physiological response to water immersion</a></li> <li><a href="/wiki/Thermal_balance_of_the_underwater_diver" title="Thermal balance of the underwater diver">Thermal balance of the underwater diver</a></li> <li><a href="/wiki/Underwater_vision" title="Underwater vision">Underwater vision</a></li> <li><a href="/wiki/Work_of_breathing" title="Work of breathing">Work of breathing</a></li></ul> </div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="Decompressiontheory" scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Decompression_theory" title="Decompression theory">Decompression<br />theory</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li>Decompression models: <ul><li><a href="/wiki/B%C3%BChlmann_decompression_algorithm" title="Bühlmann decompression algorithm">Bühlmann decompression algorithm</a></li> <li><a href="/wiki/Haldane%27s_decompression_model" title="Haldane's decompression model">Haldane's decompression model</a></li> <li><a href="/wiki/Reduced_gradient_bubble_model" title="Reduced gradient bubble model">Reduced gradient bubble model</a></li> <li><a href="/wiki/Thalmann_algorithm" title="Thalmann algorithm">Thalmann algorithm</a></li> <li><a href="/wiki/Thermodynamic_model_of_decompression" title="Thermodynamic model of decompression">Thermodynamic model of decompression</a></li> <li><a href="/wiki/Varying_Permeability_Model" title="Varying Permeability Model">Varying Permeability Model</a></li></ul></li> <li><a href="/wiki/Equivalent_air_depth" title="Equivalent air depth">Equivalent air depth</a></li> <li><a href="/wiki/Oxygen_window" title="Oxygen window">Oxygen window</a></li> <li><a href="/wiki/Physiology_of_decompression" title="Physiology of decompression">Physiology of decompression</a></li></ul> </div></td></tr></tbody></table><div> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Underwater_diving_environment" title="Underwater diving environment">Diving<br />environments</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Underwater_exploration" title="Underwater exploration">Underwater exploration</a> <ul><li><a href="/wiki/Deep-sea_exploration" title="Deep-sea exploration">Deep-sea exploration</a></li></ul></li></ul> </div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">Classification</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/List_of_diving_environments_by_type" title="List of diving environments by type">List of diving environments by type</a></li> <li><a href="/wiki/Altitude_diving" title="Altitude diving">Altitude diving</a></li> <li><a href="/wiki/Benign_water_diving" class="mw-redirect" title="Benign water diving">Benign water diving</a></li> <li><a href="/wiki/Confined_water_diving" class="mw-redirect" title="Confined water diving">Confined water diving</a></li> <li><a href="/wiki/Deep_diving" title="Deep diving">Deep diving</a></li> <li><a href="/wiki/Inland_diving" class="mw-redirect" title="Inland diving">Inland diving</a></li> <li><a href="/wiki/Inshore_diving" class="mw-redirect" title="Inshore diving">Inshore diving</a></li> <li><a href="/wiki/Muck_diving" title="Muck diving">Muck diving</a></li> <li><a href="/wiki/Night_diving" title="Night diving">Night diving</a></li> <li><a href="/wiki/Open-water_diving" title="Open-water diving">Open-water diving</a> <ul><li><a href="/wiki/Black-water_diving" class="mw-redirect" title="Black-water diving">Black-water diving</a></li> <li><a href="/wiki/Blue-water_diving" class="mw-redirect" title="Blue-water diving">Blue-water diving</a></li></ul></li> <li><a href="/wiki/Penetration_diving" title="Penetration diving">Penetration diving</a> <ul><li><a href="/wiki/Cave_diving" title="Cave diving">Cave diving</a> <ul><li><a href="/wiki/Torricellian_chamber" title="Torricellian chamber">Torricellian chamber</a></li></ul></li> <li><a href="/wiki/Ice_diving" title="Ice diving">Ice diving</a></li> <li><a href="/wiki/Wreck_diving" title="Wreck diving">Wreck diving</a></li></ul></li> <li><a href="/wiki/Recreational_dive_sites" title="Recreational dive sites">Recreational dive sites</a></li> <li><a href="/wiki/Underwater_environment" title="Underwater environment">Underwater environment</a></li> <li><a href="/wiki/Underwater_diving_environment" title="Underwater diving environment">Underwater diving environment</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Impact</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Environmental_impact_of_recreational_diving" title="Environmental impact of recreational diving">Environmental impact of recreational diving</a></li> <li><a href="/wiki/Low_impact_diving" title="Low impact diving">Low impact diving</a></li></ul> </div></td></tr></tbody></table><div> </div></td></tr></tbody></table><div> </div></td></tr></tbody></table><div></div></td></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks mw-collapsible mw-collapsed navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><div id="Other" style="font-size:114%;margin:0 4em">Other</div></th></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Bathysphere" title="Bathysphere">Bathysphere</a></li> <li><a href="/wiki/Defense_against_swimmer_incursions" title="Defense against swimmer incursions">Defense against swimmer incursions</a> <ul><li><a href="/wiki/Diver_detection_sonar" title="Diver detection sonar">Diver detection sonar</a></li></ul></li> <li><a href="/wiki/Offshore_survey" class="mw-redirect" title="Offshore survey">Offshore survey</a></li> <li><a href="/wiki/Rugged_compact_camera" class="mw-redirect" title="Rugged compact camera">Rugged compact camera</a></li> <li><a href="/wiki/Underwater_domain_awareness" title="Underwater domain awareness">Underwater domain awareness</a></li> <li><a href="/wiki/Underwater_vehicle" title="Underwater vehicle">Underwater vehicle</a></li></ul> </div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Deep-submergence_vehicle" title="Deep-submergence vehicle">Deep-submergence<br />vehicle</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Aluminaut" title="Aluminaut"><i>Aluminaut</i></a></li> <li><a href="/wiki/DSV_Alvin" title="DSV Alvin">DSV <i>Alvin</i></a></li> <li><a href="/wiki/American_submarine_NR-1" title="American submarine NR-1">American submarine NR-1</a></li> <li><a href="/wiki/Bathyscaphe" title="Bathyscaphe">Bathyscaphe</a> <ul><li><a href="/wiki/Archim%C3%A8de" title="Archimède"><i>Archimède</i></a></li> <li><a href="/wiki/FNRS-2" title="FNRS-2">FNRS-2</a></li> <li><a href="/wiki/FNRS-3" title="FNRS-3">FNRS-3</a></li> <li><a href="/wiki/Sea_Pole-class_bathyscaphe#Harmony_class_bathyscaphe" title="Sea Pole-class bathyscaphe"><i>Harmony</i> class bathyscaphe</a></li> <li><a href="/wiki/Sea_Pole-class_bathyscaphe" title="Sea Pole-class bathyscaphe"><i>Sea Pole</i>-class bathyscaphe</a></li> <li><a href="/wiki/Bathyscaphe_Trieste_II" class="mw-redirect" title="Bathyscaphe Trieste II"><i>Trieste II</i></a></li></ul></li> <li><a href="/wiki/Deepsea_Challenger" title="Deepsea Challenger"><i>Deepsea Challenger</i></a></li> <li><a href="/wiki/Ictineu_3" title="Ictineu 3"><i>Ictineu 3</i></a></li> <li><a href="/wiki/JAGO_(German_research_submersible)" title="JAGO (German research submersible)"><i>JAGO</i></a></li> <li><a href="/wiki/Jiaolong_(submersible)" title="Jiaolong (submersible)"><i>Jiaolong</i></a></li> <li><a href="/wiki/Konsul-class_submersible" title="Konsul-class submersible"><i>Konsul</i>-class submersible</a></li> <li><a href="/wiki/DSV_Limiting_Factor" title="DSV Limiting Factor"><i>Limiting Factor</i></a></li> <li><a href="/wiki/Russian_submarine_Losharik" title="Russian submarine Losharik">Russian submarine <i>Losharik</i></a></li> <li><a href="/wiki/Mir_(submersible)" title="Mir (submersible)"><i>Mir</i></a></li> <li><a href="/wiki/Nautile" title="Nautile"><i>Nautile</i></a></li> <li><a href="/wiki/Pisces-class_deep_submergence_vehicle" title="Pisces-class deep submergence vehicle"><i>Pisces</i>-class deep submergence vehicle</a></li> <li><a href="/wiki/DSV_Sea_Cliff" title="DSV Sea Cliff">DSV <i>Sea Cliff</i></a></li> <li><a href="/wiki/DSV_Shinkai" title="DSV Shinkai">DSV <i>Shinkai</i></a></li> <li><a href="/wiki/DSV_Shinkai_2000" title="DSV Shinkai 2000">DSV <i>Shinkai 2000</i></a></li> <li><a href="/wiki/DSV_Shinkai_6500" title="DSV Shinkai 6500">DSV <i>Shinkai 6500</i></a></li> <li><a href="/wiki/DSV_Turtle" title="DSV Turtle">DSV <i>Turtle</i></a></li> <li><a href="/wiki/DSV-5_Nemo" title="DSV-5 Nemo">DSV-5 <i>Nemo</i></a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Submarine_rescue" title="Submarine rescue">Submarine rescue</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/International_Submarine_Escape_and_Rescue_Liaison_Office" title="International Submarine Escape and Rescue Liaison Office">International Submarine Escape and Rescue Liaison Office</a></li> <li><a href="/wiki/Submarine_Escape_and_Rescue_system_(Royal_Swedish_Navy)" title="Submarine Escape and Rescue system (Royal Swedish Navy)">Submarine Escape and Rescue system (Royal Swedish Navy)</a></li> <li><a href="/wiki/McCann_Rescue_Chamber" title="McCann Rescue Chamber">McCann Rescue Chamber</a></li> <li><a href="/wiki/Submarine_rescue_ship" title="Submarine rescue ship">Submarine rescue ship</a></li></ul> </div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="Deep-submergencerescue_vehicle" scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Deep-submergence_rescue_vehicle" title="Deep-submergence rescue vehicle">Deep-submergence<br />rescue vehicle</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/LR5" title="LR5">LR5</a></li> <li><a href="/wiki/LR7" title="LR7">LR7</a></li> <li><a href="/wiki/MSM-1" title="MSM-1">MSM-1</a></li> <li><a href="/wiki/Mystic-class_deep-submergence_rescue_vehicle" title="Mystic-class deep-submergence rescue vehicle"><i>Mystic</i>-class deep-submergence rescue vehicle</a> <ul><li><a href="/wiki/DSRV-1_Mystic" title="DSRV-1 Mystic">DSRV-1 <i>Mystic</i></a></li> <li><a href="/wiki/DSRV-2_Avalon" title="DSRV-2 Avalon">DSRV-2 <i>Avalon</i></a></li></ul></li> <li><a href="/wiki/NATO_Submarine_Rescue_System" title="NATO Submarine Rescue System">NATO Submarine Rescue System</a></li> <li><a href="/wiki/Priz-class_deep-submergence_rescue_vehicle" title="Priz-class deep-submergence rescue vehicle"><i>Priz</i>-class deep-submergence rescue vehicle</a> <ul><li><a href="/wiki/Russian_deep_submergence_rescue_vehicle_AS-28" title="Russian deep submergence rescue vehicle AS-28">Russian deep submergence rescue vehicle AS-28</a></li> <li><a href="/wiki/Russian_submarine_AS-34" title="Russian submarine AS-34">Russian submarine AS-34</a></li></ul></li> <li><a href="/wiki/ASRV_Remora" class="mw-redirect" title="ASRV Remora">ASRV <i>Remora</i></a></li> <li><a href="/wiki/SRV-300" title="SRV-300">SRV-300</a></li> <li><a href="/wiki/Submarine_Rescue_Diving_Recompression_System" title="Submarine Rescue Diving Recompression System">Submarine Rescue Diving Recompression System</a></li> <li><a href="/wiki/Type_7103_DSRV" class="mw-redirect" title="Type 7103 DSRV">Type 7103 DSRV</a></li> <li><a href="/wiki/URF_(Swedish_Navy)" title="URF (Swedish Navy)">URF (Swedish Navy)</a></li></ul> </div></td></tr></tbody></table><div> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/w/index.php?title=Submarine_escape&action=edit&redlink=1" class="new" title="Submarine escape (page does not exist)">Submarine escape</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Escape_trunk" title="Escape trunk">Escape trunk</a></li> <li><a href="/wiki/Submarine_escape_training_facility" title="Submarine escape training facility">Submarine escape training facility</a></li> <li><a href="/wiki/Submarine_Escape_Training_Facility_(Australia)" title="Submarine Escape Training Facility (Australia)">Submarine Escape Training Facility (Australia)</a></li></ul> </div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="Escape_set" scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Escape_set" class="mw-redirect" title="Escape set">Escape set</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Davis_Submerged_Escape_Apparatus" title="Davis Submerged Escape Apparatus">Davis Submerged Escape Apparatus</a></li> <li><a href="/wiki/Momsen_lung" title="Momsen lung">Momsen lung</a></li> <li><a href="/wiki/Steinke_hood" title="Steinke hood">Steinke hood</a></li> <li><a href="/wiki/Submarine_Escape_Immersion_Equipment" title="Submarine Escape Immersion Equipment">Submarine Escape Immersion Equipment</a></li></ul> </div></td></tr></tbody></table><div> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Special<br />interest<br />groups</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Artificial_Reef_Society_of_British_Columbia" title="Artificial Reef Society of British Columbia">Artificial Reef Society of British Columbia</a></li> <li><a href="/wiki/CMAS_Europe" title="CMAS Europe">CMAS Europe</a></li> <li><a href="/wiki/Coral_Reef_Alliance" title="Coral Reef Alliance">Coral Reef Alliance</a></li> <li><a href="/wiki/Divers_Alert_Network" title="Divers Alert Network">Divers Alert Network</a></li> <li><a href="/wiki/Green_Fins" title="Green Fins">Green Fins</a></li> <li><a href="/wiki/Finger_Lakes_Underwater_Preserve_Association" title="Finger Lakes Underwater Preserve Association">Finger Lakes Underwater Preserve Association</a></li> <li><a href="/wiki/Karst_Underwater_Research" title="Karst Underwater Research">Karst Underwater Research</a></li> <li><a href="/wiki/Nautical_Archaeology_Program" title="Nautical Archaeology Program">Nautical Archaeology Program</a></li> <li><a href="/wiki/Nautical_Archaeology_Society" title="Nautical Archaeology Society">Nautical Archaeology Society</a></li> <li><a href="/wiki/Naval_Air_Command_Sub_Aqua_Club" title="Naval Air Command Sub Aqua Club">Naval Air Command Sub Aqua Club</a></li> <li><a href="/wiki/PADI_AWARE" title="PADI AWARE">PADI AWARE</a></li> <li><a href="/wiki/Reef_Check" title="Reef Check">Reef Check</a></li> <li><a href="/wiki/Reef_Life_Survey" title="Reef Life Survey">Reef Life Survey</a></li> <li><a href="/wiki/Rubicon_Foundation" title="Rubicon Foundation">Rubicon Foundation</a></li> <li><a href="/wiki/Save_Ontario_Shipwrecks" title="Save Ontario Shipwrecks">Save Ontario Shipwrecks</a></li> <li><a href="/wiki/SeaKeys" title="SeaKeys">SeaKeys</a></li> <li><a href="/wiki/Sea_Research_Society" title="Sea Research Society">Sea Research Society</a></li> <li><a href="/wiki/Society_for_Underwater_Historical_Research" title="Society for Underwater Historical Research">Society for Underwater Historical Research</a></li> <li><a href="/wiki/Society_for_Underwater_Technology" title="Society for Underwater Technology">Society for Underwater Technology</a></li> <li><a href="/wiki/Underwater_Archaeology_Branch,_Naval_History_%26_Heritage_Command" title="Underwater Archaeology Branch, Naval History & Heritage Command">Underwater Archaeology Branch, Naval History & Heritage Command</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Neutral buoyancy<br />facilities for<br />Astronaut training</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Neutral_Buoyancy_Laboratory" title="Neutral Buoyancy Laboratory">Neutral Buoyancy Laboratory</a></li> <li><a href="/wiki/Neutral_buoyancy_pool" title="Neutral buoyancy pool">Neutral buoyancy pool</a></li> <li><a href="/wiki/Neutral_buoyancy_simulation_as_a_training_aid" title="Neutral buoyancy simulation as a training aid">Neutral buoyancy simulation as a training aid</a></li> <li><a href="/wiki/Neutral_Buoyancy_Simulator" title="Neutral Buoyancy Simulator">Neutral Buoyancy Simulator</a></li> <li><a href="/wiki/Space_Systems_Laboratory_(Maryland)" title="Space Systems Laboratory (Maryland)">Space Systems Laboratory</a></li> <li><a href="/wiki/Yuri_Gagarin_Cosmonaut_Training_Center" title="Yuri Gagarin Cosmonaut Training Center">Yuri Gagarin Cosmonaut Training Center</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Other</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Nautilus_Productions" title="Nautilus Productions">Nautilus Productions</a></li> <li><a href="/wiki/Helicopter_Aircrew_Breathing_Device" title="Helicopter Aircrew Breathing Device">Helicopter Aircrew Breathing Device</a></li> <li><a href="/wiki/Scuba_diving_therapy" title="Scuba diving therapy">Scuba diving therapy</a></li> <li><a href="/wiki/Seabed_mining" title="Seabed mining">Seabed mining</a></li></ul> </div></td></tr></tbody></table><div> </div></td></tr></tbody></table><div></div></td></tr><tr><td class="navbox-abovebelow" colspan="2" style="font-weight: bold;"><div> <ul><li><span class="noviewer" typeof="mw:File"><span title="Category"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/16px-Symbol_category_class.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/23px-Symbol_category_class.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/31px-Symbol_category_class.svg.png 2x" data-file-width="180" data-file-height="185" /></span></span> <b><a href="/wiki/Category:Underwater_diving" title="Category:Underwater diving">Category</a></b></li> <li><span class="noviewer" typeof="mw:File"><span title="Commons page"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/12px-Commons-logo.svg.png" decoding="async" width="12" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/18px-Commons-logo.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/24px-Commons-logo.svg.png 2x" data-file-width="1024" data-file-height="1376" /></span></span> <b><a href="https://commons.wikimedia.org/wiki/Category:Underwater_diving" class="extiw" title="commons:Category:Underwater diving">Commons</a></b></li> <li><span class="noviewer" typeof="mw:File"><span title="List-Class article"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/d/db/Symbol_list_class.svg/16px-Symbol_list_class.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/d/db/Symbol_list_class.svg/23px-Symbol_list_class.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/d/db/Symbol_list_class.svg/31px-Symbol_list_class.svg.png 2x" data-file-width="180" data-file-height="185" /></span></span> <b><a href="/wiki/Glossary_of_underwater_diving_terminology" title="Glossary of underwater diving terminology">Glossary</a></b></li> <li><b>Indexes: <a href="/wiki/Index_of_recreational_dive_sites" title="Index of recreational dive sites">Dive sites</a></b></li> <li><b><a href="/wiki/Index_of_underwater_divers" title="Index of underwater divers">Divers</a></b></li> <li><b><a href="/wiki/Index_of_underwater_diving" title="Index of underwater diving">Diving</a></b></li> <li><span class="noviewer" typeof="mw:File"><span title="Outline"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/4/41/Global_thinking.svg/10px-Global_thinking.svg.png" decoding="async" width="10" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/4/41/Global_thinking.svg/15px-Global_thinking.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/4/41/Global_thinking.svg/21px-Global_thinking.svg.png 2x" data-file-width="130" data-file-height="200" /></span></span> <b><a href="/wiki/Outline_of_underwater_diving" title="Outline of underwater diving">Outline</a></b></li> <li><span class="noviewer" typeof="mw:File"><a href="/wiki/File:Symbol_portal_class.svg" class="mw-file-description" title="Portal"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/e/e2/Symbol_portal_class.svg/16px-Symbol_portal_class.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/e/e2/Symbol_portal_class.svg/23px-Symbol_portal_class.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/e/e2/Symbol_portal_class.svg/31px-Symbol_portal_class.svg.png 2x" data-file-width="180" data-file-height="185" /></a></span> <b><a href="/wiki/Portal:Underwater_diving" title="Portal:Underwater diving">Portal</a></b></li></ul> </div></td></tr></tbody></table></div>    </div><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?type=1x1" alt="" width="1" height="1" style="border: none; position: absolute;"></noscript> <div class="printfooter" data-nosnippet="">Retrieved from "<a dir="ltr" href="https://en.wikipedia.org/w/index.php?title=Rebreather_diving&oldid=1255436050#Venting_the_loop">https://en.wikipedia.org/w/index.php?title=Rebreather_diving&oldid=1255436050#Venting_the_loop</a>"</div></div> <div id="catlinks" class="catlinks" data-mw="interface"><div id="mw-normal-catlinks" class="mw-normal-catlinks"><a href="/wiki/Help:Category" title="Help:Category">Category</a>: <ul><li><a href="/wiki/Category:Underwater_diving_modes" title="Category:Underwater diving modes">Underwater diving modes</a></li></ul></div><div id="mw-hidden-catlinks" class="mw-hidden-catlinks mw-hidden-cats-hidden">Hidden categories: <ul><li><a href="/wiki/Category:CS1:_long_volume_value" title="Category:CS1: long volume value">CS1: long volume value</a></li><li><a href="/wiki/Category:All_articles_with_dead_external_links" title="Category:All articles with dead external links">All articles with dead external links</a></li><li><a href="/wiki/Category:Articles_with_dead_external_links_from_June_2024" title="Category:Articles with dead external links from June 2024">Articles with dead external links from June 2024</a></li><li><a href="/wiki/Category:Articles_with_short_description" title="Category:Articles with short description">Articles with short description</a></li><li><a href="/wiki/Category:Short_description_matches_Wikidata" title="Category:Short description matches Wikidata">Short description matches Wikidata</a></li><li><a href="/wiki/Category:Use_dmy_dates_from_May_2022" title="Category:Use dmy dates from May 2022">Use dmy dates from May 2022</a></li><li><a href="/wiki/Category:All_articles_with_unsourced_statements" title="Category:All articles with unsourced statements">All articles with unsourced statements</a></li><li><a href="/wiki/Category:Articles_with_unsourced_statements_from_April_2013" title="Category:Articles with unsourced statements from April 2013">Articles with unsourced statements from April 2013</a></li><li><a href="/wiki/Category:Articles_with_unsourced_statements_from_May_2021" title="Category:Articles with unsourced statements from May 2021">Articles with unsourced statements from May 2021</a></li><li><a href="/wiki/Category:Articles_to_be_expanded_from_May_2021" title="Category:Articles to be expanded from May 2021">Articles to be expanded from May 2021</a></li><li><a href="/wiki/Category:All_articles_to_be_expanded" title="Category:All articles to be expanded">All articles to be expanded</a></li><li><a href="/wiki/Category:Articles_with_unsourced_statements_from_June_2024" title="Category:Articles with unsourced statements from June 2024">Articles with unsourced statements from June 2024</a></li><li><a href="/wiki/Category:Articles_to_be_expanded_from_September_2024" title="Category:Articles to be expanded from September 2024">Articles to be expanded from September 2024</a></li><li><a href="/wiki/Category:Articles_to_be_expanded_from_February_2024" title="Category:Articles to be expanded from February 2024">Articles to be expanded from February 2024</a></li><li><a href="/wiki/Category:Articles_to_be_expanded_from_May_2024" title="Category:Articles to be expanded from May 2024">Articles to be expanded from May 2024</a></li><li><a href="/wiki/Category:Wikipedia_articles_needing_clarification_from_October_2021" title="Category:Wikipedia articles needing clarification from October 2021">Wikipedia articles needing clarification from October 2021</a></li></ul></div></div> </div> </main> </div> <div class="mw-footer-container"> <footer id="footer" class="mw-footer" > <ul id="footer-info"> <li id="footer-info-lastmod"> This page was last edited on 4 November 2024, at 23:20<span class="anonymous-show"> (UTC)</span>.</li> <li id="footer-info-copyright">Text is available under the <a href="/wiki/Wikipedia:Text_of_the_Creative_Commons_Attribution-ShareAlike_4.0_International_License" title="Wikipedia:Text of the Creative Commons Attribution-ShareAlike 4.0 International License">Creative Commons Attribution-ShareAlike 4.0 License</a>; additional terms may apply. By using this site, you agree to the <a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Terms_of_Use" class="extiw" title="foundation:Special:MyLanguage/Policy:Terms of Use">Terms of Use</a> and <a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Privacy_policy" class="extiw" title="foundation:Special:MyLanguage/Policy:Privacy policy">Privacy Policy</a>. Wikipedia® is a registered trademark of the <a rel="nofollow" class="external text" href="https://wikimediafoundation.org/">Wikimedia Foundation, Inc.</a>, a non-profit organization.</li> </ul> <ul id="footer-places"> <li id="footer-places-privacy"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Privacy_policy">Privacy policy</a></li> <li id="footer-places-about"><a href="/wiki/Wikipedia:About">About Wikipedia</a></li> <li id="footer-places-disclaimers"><a href="/wiki/Wikipedia:General_disclaimer">Disclaimers</a></li> <li id="footer-places-contact"><a href="//en.wikipedia.org/wiki/Wikipedia:Contact_us">Contact Wikipedia</a></li> <li id="footer-places-wm-codeofconduct"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Universal_Code_of_Conduct">Code of Conduct</a></li> <li id="footer-places-developers"><a href="https://developer.wikimedia.org">Developers</a></li> <li id="footer-places-statslink"><a href="https://stats.wikimedia.org/#/en.wikipedia.org">Statistics</a></li> <li id="footer-places-cookiestatement"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Cookie_statement">Cookie statement</a></li> <li id="footer-places-mobileview"><a href="//en.m.wikipedia.org/w/index.php?title=Rebreather_diving&mobileaction=toggle_view_mobile#Venting_the_loop" class="noprint stopMobileRedirectToggle">Mobile view</a></li> </ul> <ul id="footer-icons" class="noprint"> <li id="footer-copyrightico"><a href="https://wikimediafoundation.org/" class="cdx-button cdx-button--fake-button cdx-button--size-large cdx-button--fake-button--enabled"><img src="/static/images/footer/wikimedia-button.svg" width="84" height="29" alt="Wikimedia Foundation" loading="lazy"></a></li> <li id="footer-poweredbyico"><a href="https://www.mediawiki.org/" class="cdx-button cdx-button--fake-button cdx-button--size-large cdx-button--fake-button--enabled"><img src="/w/resources/assets/poweredby_mediawiki.svg" alt="Powered by MediaWiki" width="88" height="31" loading="lazy"></a></li> </ul> </footer> </div> </div> </div> <div class="vector-settings" id="p-dock-bottom"> <ul></ul> </div><script>(RLQ=window.RLQ||[]).push(function(){mw.config.set({"wgHostname":"mw-web.codfw.main-f69cdc8f6-ps8jv","wgBackendResponseTime":292,"wgPageParseReport":{"limitreport":{"cputime":"2.072","walltime":"2.457","ppvisitednodes":{"value":11522,"limit":1000000},"postexpandincludesize":{"value":691992,"limit":2097152},"templateargumentsize":{"value":10961,"limit":2097152},"expansiondepth":{"value":17,"limit":100},"expensivefunctioncount":{"value":27,"limit":500},"unstrip-depth":{"value":1,"limit":20},"unstrip-size":{"value":360028,"limit":5000000},"entityaccesscount":{"value":0,"limit":400},"timingprofile":["100.00% 1694.737 1 -total"," 39.58% 670.749 1 Template:Reflist"," 17.02% 288.518 36 Template:Cite_web"," 14.84% 251.487 1 Template:UnderwaterDiving"," 13.98% 236.904 1 Template:Navbox_with_collapsible_groups"," 8.83% 149.662 4 Template:Annotated_link"," 8.21% 139.197 35 Template:Navbox"," 7.08% 120.022 1 Template:Short_description"," 5.50% 93.193 9 Template:Fix"," 5.46% 92.602 16 Template:Cite_journal"]},"scribunto":{"limitreport-timeusage":{"value":"1.004","limit":"10.000"},"limitreport-memusage":{"value":15407017,"limit":52428800},"limitreport-profile":[["MediaWiki\\Extension\\Scribunto\\Engines\\LuaSandbox\\LuaSandboxCallback::callParserFunction","260","25.0"],["?","240","23.1"],["recursiveClone \u003CmwInit.lua:45\u003E","80","7.7"],["MediaWiki\\Extension\\Scribunto\\Engines\\LuaSandbox\\LuaSandboxCallback::find","60","5.8"],["MediaWiki\\Extension\\Scribunto\\Engines\\LuaSandbox\\LuaSandboxCallback::getExpandedArgument","40","3.8"],["is_valid_date \u003CModule:Citation/CS1/Date_validation:210\u003E","40","3.8"],["dataWrapper \u003Cmw.lua:672\u003E","40","3.8"],["MediaWiki\\Extension\\Scribunto\\Engines\\LuaSandbox\\LuaSandboxCallback::match","40","3.8"],["concat","20","1.9"],["format","20","1.9"],["[others]","200","19.2"]]},"cachereport":{"origin":"mw-web.codfw.main-f69cdc8f6-hhmqd","timestamp":"20241122153229","ttl":2592000,"transientcontent":false}}});});</script> <script type="application/ld+json">{"@context":"https:\/\/schema.org","@type":"Article","name":"Rebreather diving","url":"https:\/\/en.wikipedia.org\/wiki\/Rebreather_diving#Venting_the_loop","sameAs":"http:\/\/www.wikidata.org\/entity\/Q12066983","mainEntity":"http:\/\/www.wikidata.org\/entity\/Q12066983","author":{"@type":"Organization","name":"Contributors to Wikimedia projects"},"publisher":{"@type":"Organization","name":"Wikimedia Foundation, Inc.","logo":{"@type":"ImageObject","url":"https:\/\/www.wikimedia.org\/static\/images\/wmf-hor-googpub.png"}},"datePublished":"2013-04-23T09:14:19Z","dateModified":"2024-11-04T23:20:49Z","image":"https:\/\/upload.wikimedia.org\/wikipedia\/commons\/5\/5d\/USMC_combatant_diving_%282nd_Recon_Bn%29.jpg","headline":"underwater diving using self contained breathing gas recycling apparatus"}</script> </body> </html>