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class="vector-toc-numb">2</span> <span>Indices by location</span> </div> </a> <button aria-controls="toc-Indices_by_location-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 Indices by location subsection</span> </button> <ul id="toc-Indices_by_location-sublist" class="vector-toc-list"> <li id="toc-Australia" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Australia"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.1</span> <span>Australia</span> </div> </a> <ul id="toc-Australia-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Canada" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Canada"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.2</span> <span>Canada</span> </div> </a> <ul id="toc-Canada-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-China" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#China"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.3</span> <span>China</span> </div> </a> <ul id="toc-China-sublist" class="vector-toc-list"> <li id="toc-Hong_Kong" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Hong_Kong"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.3.1</span> <span>Hong Kong</span> </div> </a> <ul id="toc-Hong_Kong-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Mainland_China" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Mainland_China"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.3.2</span> <span>Mainland China</span> </div> </a> <ul id="toc-Mainland_China-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Europe" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Europe"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.4</span> <span>Europe</span> </div> </a> <ul id="toc-Europe-sublist" class="vector-toc-list"> <li id="toc-CAQI" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#CAQI"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.4.1</span> <span>CAQI</span> </div> </a> <ul id="toc-CAQI-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-India" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#India"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.5</span> <span>India</span> </div> </a> <ul id="toc-India-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Japan" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Japan"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.6</span> <span>Japan</span> </div> </a> <ul id="toc-Japan-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Mexico" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Mexico"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.7</span> <span>Mexico</span> </div> </a> <ul id="toc-Mexico-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Singapore" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Singapore"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.8</span> <span>Singapore</span> </div> </a> <ul id="toc-Singapore-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-South_Korea" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#South_Korea"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.9</span> <span>South Korea</span> </div> </a> <ul id="toc-South_Korea-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-United_Kingdom" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#United_Kingdom"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.10</span> <span>United Kingdom</span> </div> </a> <ul id="toc-United_Kingdom-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-United_States" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#United_States"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.11</span> <span>United States</span> </div> </a> <ul id="toc-United_States-sublist" class="vector-toc-list"> <li id="toc-Computing_the_AQI" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Computing_the_AQI"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.11.1</span> <span>Computing the AQI</span> </div> </a> <ul id="toc-Computing_the_AQI-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Public_availability_of_the_AQI" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Public_availability_of_the_AQI"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.11.2</span> <span>Public availability of the AQI</span> </div> </a> <ul id="toc-Public_availability_of_the_AQI-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Regulatory_Air_Monitors_and_Low_Cost_Sensors" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Regulatory_Air_Monitors_and_Low_Cost_Sensors"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.11.3</span> <span>Regulatory Air Monitors and Low Cost Sensors</span> </div> </a> <ul id="toc-Regulatory_Air_Monitors_and_Low_Cost_Sensors-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-History_of_the_AQI" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#History_of_the_AQI"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.11.4</span> <span>History of the AQI</span> </div> </a> <ul id="toc-History_of_the_AQI-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> </ul> </li> <li id="toc-See_also" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#See_also"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</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 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#References"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>References</span> </div> </a> <ul id="toc-References-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-External_links" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#External_links"> <div class="vector-toc-text"> <span class="vector-toc-numb">5</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">Air quality index</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="Go to an article in another language. Available in 29 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-29" 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">29 languages</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-ar mw-list-item"><a href="https://ar.wikipedia.org/wiki/%D9%85%D8%A4%D8%B4%D8%B1_%D8%AC%D9%88%D8%AF%D8%A9_%D8%A7%D9%84%D9%87%D9%88%D8%A7%D8%A1" title="مؤشر جودة الهواء – Arabic" lang="ar" hreflang="ar" data-title="مؤشر جودة الهواء" data-language-autonym="العربية" data-language-local-name="Arabic" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-be-x-old mw-list-item"><a href="https://be-tarask.wikipedia.org/wiki/%D0%86%D0%BD%D0%B4%D1%8D%D0%BA%D1%81_%D1%8F%D0%BA%D0%B0%D1%81%D1%8C%D1%86%D1%96_%D0%BF%D0%B0%D0%B2%D0%B5%D1%82%D1%80%D0%B0" title="Індэкс якасьці паветра – Belarusian (Taraškievica orthography)" lang="be-tarask" hreflang="be-tarask" data-title="Індэкс якасьці паветра" data-language-autonym="Беларуская (тарашкевіца)" data-language-local-name="Belarusian (Taraškievica orthography)" class="interlanguage-link-target"><span>Беларуская (тарашкевіца)</span></a></li><li class="interlanguage-link interwiki-bh mw-list-item"><a href="https://bh.wikipedia.org/wiki/%E0%A4%B9%E0%A4%B5%E0%A4%BE_%E0%A4%95%E0%A5%8D%E0%A4%B5%E0%A4%BE%E0%A4%B2%E0%A4%BF%E0%A4%9F%E0%A5%80_%E0%A4%87%E0%A4%82%E0%A4%A1%E0%A5%87%E0%A4%95%E0%A5%8D%E0%A4%B8" title="हवा क्वालिटी इंडेक्स – Bhojpuri" lang="bh" hreflang="bh" data-title="हवा क्वालिटी इंडेक्स" data-language-autonym="भोजपुरी" data-language-local-name="Bhojpuri" class="interlanguage-link-target"><span>भोजपुरी</span></a></li><li class="interlanguage-link interwiki-bo mw-list-item"><a href="https://bo.wikipedia.org/wiki/%E0%BD%98%E0%BD%81%E0%BD%A0%E0%BC%8B%E0%BD%A2%E0%BE%B3%E0%BD%B4%E0%BD%84%E0%BC%8B%E0%BD%A6%E0%BE%A4%E0%BD%B4%E0%BD%A6%E0%BC%8B%E0%BD%9A%E0%BD%91%E0%BC%8B%E0%BD%A6%E0%BE%9F%E0%BD%BC%E0%BD%93%E0%BC%8B%E0%BD%82%E0%BE%B2%E0%BD%84%E0%BD%A6%E0%BC%8D" title="མཁའ་རླུང་སྤུས་ཚད་སྟོན་གྲངས། – Tibetan" lang="bo" hreflang="bo" data-title="མཁའ་རླུང་སྤུས་ཚད་སྟོན་གྲངས།" data-language-autonym="བོད་ཡིག" data-language-local-name="Tibetan" class="interlanguage-link-target"><span>བོད་ཡིག</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/%C3%8Dndex_de_Qualitat_de_l%27Aire" title="Índex de Qualitat de l'Aire – Catalan" lang="ca" hreflang="ca" data-title="Índex de Qualitat de l'Aire" data-language-autonym="Català" data-language-local-name="Catalan" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-cy mw-list-item"><a href="https://cy.wikipedia.org/wiki/Mynegai_ansawdd_aer" title="Mynegai ansawdd aer – Welsh" lang="cy" hreflang="cy" data-title="Mynegai ansawdd aer" data-language-autonym="Cymraeg" data-language-local-name="Welsh" class="interlanguage-link-target"><span>Cymraeg</span></a></li><li class="interlanguage-link interwiki-de badge-Q70894304 mw-list-item" title=""><a href="https://de.wikipedia.org/wiki/Luftg%C3%BCte" title="Luftgüte – German" lang="de" hreflang="de" data-title="Luftgüte" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/%C3%8Dndice_de_calidad_del_aire" title="Índice de calidad del aire – Spanish" lang="es" hreflang="es" data-title="Índice de calidad del aire" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-eu mw-list-item"><a href="https://eu.wikipedia.org/wiki/Airearen_kalitate_indize" title="Airearen kalitate indize – Basque" lang="eu" hreflang="eu" data-title="Airearen kalitate indize" data-language-autonym="Euskara" data-language-local-name="Basque" class="interlanguage-link-target"><span>Euskara</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%D8%B4%D8%A7%D8%AE%D8%B5_%DA%A9%DB%8C%D9%81%DB%8C%D8%AA_%D9%87%D9%88%D8%A7" title="شاخص کیفیت هوا – Persian" lang="fa" hreflang="fa" data-title="شاخص کیفیت هوا" data-language-autonym="فارسی" data-language-local-name="Persian" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Indice_de_qualit%C3%A9_de_l%27air" title="Indice de qualité de l'air – French" lang="fr" hreflang="fr" data-title="Indice de qualité de l'air" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/%EB%8C%80%EA%B8%B0%EC%A7%88_%EC%A7%80%EC%88%98" title="대기질 지수 – Korean" lang="ko" hreflang="ko" data-title="대기질 지수" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-ha mw-list-item"><a href="https://ha.wikipedia.org/wiki/%C6%98ididdigar_ingancin_iska" title="Ƙididdigar ingancin iska – Hausa" lang="ha" hreflang="ha" data-title="Ƙididdigar ingancin iska" data-language-autonym="Hausa" data-language-local-name="Hausa" class="interlanguage-link-target"><span>Hausa</span></a></li><li class="interlanguage-link interwiki-ig mw-list-item"><a href="https://ig.wikipedia.org/wiki/Akara_Ngosi_ikuku" title="Akara Ngosi ikuku – Igbo" lang="ig" hreflang="ig" data-title="Akara Ngosi ikuku" data-language-autonym="Igbo" data-language-local-name="Igbo" class="interlanguage-link-target"><span>Igbo</span></a></li><li class="interlanguage-link interwiki-id mw-list-item"><a href="https://id.wikipedia.org/wiki/Indeks_kualitas_udara" title="Indeks kualitas udara – Indonesian" lang="id" hreflang="id" data-title="Indeks kualitas udara" data-language-autonym="Bahasa Indonesia" data-language-local-name="Indonesian" class="interlanguage-link-target"><span>Bahasa Indonesia</span></a></li><li class="interlanguage-link interwiki-mk mw-list-item"><a href="https://mk.wikipedia.org/wiki/%D0%98%D0%BD%D0%B4%D0%B5%D0%BA%D1%81_%D0%B7%D0%B0_%D0%BA%D0%B2%D0%B0%D0%BB%D0%B8%D1%82%D0%B5%D1%82_%D0%BD%D0%B0_%D0%B2%D0%BE%D0%B7%D0%B4%D1%83%D1%85%D0%BE%D1%82" title="Индекс за квалитет на воздухот – Macedonian" lang="mk" hreflang="mk" data-title="Индекс за квалитет на воздухот" data-language-autonym="Македонски" data-language-local-name="Macedonian" class="interlanguage-link-target"><span>Македонски</span></a></li><li class="interlanguage-link interwiki-ms mw-list-item"><a href="https://ms.wikipedia.org/wiki/Indeks_kualiti_udara" title="Indeks kualiti udara – Malay" lang="ms" hreflang="ms" data-title="Indeks kualiti udara" data-language-autonym="Bahasa Melayu" data-language-local-name="Malay" class="interlanguage-link-target"><span>Bahasa Melayu</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/%E7%A9%BA%E6%B0%97%E8%B3%AA%E6%8C%87%E6%95%B0" title="空気質指数 – Japanese" lang="ja" hreflang="ja" data-title="空気質指数" data-language-autonym="日本語" data-language-local-name="Japanese" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/Wska%C5%BAnik_jako%C5%9Bci_powietrza" title="Wskaźnik jakości powietrza – Polish" lang="pl" hreflang="pl" data-title="Wskaźnik jakości powietrza" data-language-autonym="Polski" data-language-local-name="Polish" class="interlanguage-link-target"><span>Polski</span></a></li><li class="interlanguage-link interwiki-pt mw-list-item"><a href="https://pt.wikipedia.org/wiki/%C3%8Dndice_de_qualidade_do_ar" title="Índice de qualidade do ar – Portuguese" lang="pt" hreflang="pt" data-title="Índice de qualidade do ar" data-language-autonym="Português" data-language-local-name="Portuguese" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-ro mw-list-item"><a href="https://ro.wikipedia.org/wiki/Indicele_de_calitate_a_aerului" title="Indicele de calitate a aerului – Romanian" lang="ro" hreflang="ro" data-title="Indicele de calitate a aerului" data-language-autonym="Română" data-language-local-name="Romanian" class="interlanguage-link-target"><span>Română</span></a></li><li class="interlanguage-link interwiki-fi mw-list-item"><a href="https://fi.wikipedia.org/wiki/Ilmanlaatuindeksi" title="Ilmanlaatuindeksi – Finnish" lang="fi" hreflang="fi" data-title="Ilmanlaatuindeksi" data-language-autonym="Suomi" data-language-local-name="Finnish" class="interlanguage-link-target"><span>Suomi</span></a></li><li class="interlanguage-link interwiki-sv mw-list-item"><a href="https://sv.wikipedia.org/wiki/Luftkvalitetsindex" title="Luftkvalitetsindex – Swedish" lang="sv" hreflang="sv" data-title="Luftkvalitetsindex" data-language-autonym="Svenska" data-language-local-name="Swedish" class="interlanguage-link-target"><span>Svenska</span></a></li><li class="interlanguage-link interwiki-ta mw-list-item"><a href="https://ta.wikipedia.org/wiki/%E0%AE%95%E0%AE%BE%E0%AE%B1%E0%AF%8D%E0%AE%B1%E0%AF%81%E0%AE%A4%E0%AF%8D_%E0%AE%A4%E0%AE%B0%E0%AE%9A%E0%AF%8D_%E0%AE%9A%E0%AF%81%E0%AE%9F%E0%AF%8D%E0%AE%9F%E0%AF%86%E0%AE%A3%E0%AF%8D" title="காற்றுத் தரச் சுட்டெண் – Tamil" lang="ta" hreflang="ta" data-title="காற்றுத் தரச் சுட்டெண்" data-language-autonym="தமிழ்" data-language-local-name="Tamil" class="interlanguage-link-target"><span>தமிழ்</span></a></li><li class="interlanguage-link interwiki-th mw-list-item"><a href="https://th.wikipedia.org/wiki/%E0%B8%94%E0%B8%B1%E0%B8%8A%E0%B8%99%E0%B8%B5%E0%B8%84%E0%B8%B8%E0%B8%93%E0%B8%A0%E0%B8%B2%E0%B8%9E%E0%B8%AD%E0%B8%B2%E0%B8%81%E0%B8%B2%E0%B8%A8" title="ดัชนีคุณภาพอากาศ – Thai" lang="th" hreflang="th" data-title="ดัชนีคุณภาพอากาศ" data-language-autonym="ไทย" data-language-local-name="Thai" class="interlanguage-link-target"><span>ไทย</span></a></li><li class="interlanguage-link interwiki-tr mw-list-item"><a href="https://tr.wikipedia.org/wiki/Hava_kalitesi_indeksi" title="Hava kalitesi indeksi – Turkish" lang="tr" hreflang="tr" data-title="Hava kalitesi indeksi" data-language-autonym="Türkçe" data-language-local-name="Turkish" class="interlanguage-link-target"><span>Türkçe</span></a></li><li class="interlanguage-link interwiki-uk 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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"></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">Measure of air pollution</div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:25August_2007_Greek_fires.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/b/b7/25August_2007_Greek_fires.jpg/170px-25August_2007_Greek_fires.jpg" decoding="async" width="170" height="177" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/b7/25August_2007_Greek_fires.jpg/255px-25August_2007_Greek_fires.jpg 1.5x, 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a{color:var(--color-progressive)!important}}@media print{body.ns-0 .mw-parser-output .sidebar{display:none!important}}</style><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1246091330"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1246091330"><table class="sidebar sidebar-collapse nomobile nowraplinks hlist"><tbody><tr><td class="sidebar-pretitle">Part of a <a href="/wiki/Category:Pollution" title="Category:Pollution">series</a> on</td></tr><tr><th class="sidebar-title-with-pretitle" style="padding-bottom:0; background:#fadcc5; color:#fadcc5"><a href="/wiki/Pollution" title="Pollution">Pollution</a></th></tr><tr><td class="sidebar-image"><span class="mw-default-size" typeof="mw:File/Frameless"><a href="/wiki/File:Air_pollution3.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/0/0d/Air_pollution3.jpg/220px-Air_pollution3.jpg" decoding="async" width="220" height="124" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/0/0d/Air_pollution3.jpg/330px-Air_pollution3.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/0/0d/Air_pollution3.jpg/440px-Air_pollution3.jpg 2x" data-file-width="4000" data-file-height="2250" /></a></span><div class="sidebar-caption">Air pollution from a factory</div></td></tr><tr><td class="sidebar-content" style="padding-top:0.1em;"> <div class="sidebar-list mw-collapsible"><div class="sidebar-list-title" style="background:#fadcc5;text-align:center;;color: var(--color-base)"><a href="/wiki/Air_pollution" title="Air pollution">Air</a></div><div class="sidebar-list-content mw-collapsible-content"> <ul><li><a href="/wiki/Acid_rain" title="Acid rain">Acid rain</a></li> <li><a class="mw-selflink selflink">Air quality index</a></li> <li><a href="/wiki/Atmospheric_dispersion_modeling" title="Atmospheric dispersion modeling">Atmospheric dispersion modeling</a></li> <li><a href="/wiki/Chlorofluorocarbon" title="Chlorofluorocarbon">Chlorofluorocarbon</a></li> <li><a href="/wiki/Combustion" title="Combustion">Combustion</a></li> <li><a href="/wiki/Exhaust_gas" title="Exhaust gas">Exhaust gas</a></li> <li><a href="/wiki/Haze" title="Haze">Haze</a></li> <li><a href="/wiki/Global_dimming" title="Global dimming">Global dimming</a></li> <li><a href="/wiki/Global_distillation" title="Global distillation">Global distillation</a></li> <li><a href="/wiki/Indoor_air_quality" title="Indoor air quality">Indoor air quality</a></li> <li><a href="/wiki/Ozone_depletion" title="Ozone depletion">Ozone depletion</a></li> <li><a href="/wiki/Particulates" title="Particulates">Particulates</a></li> <li><a href="/wiki/Persistent_organic_pollutant" title="Persistent organic pollutant">Persistent organic pollutant</a></li> <li><a href="/wiki/Smog" title="Smog">Smog</a></li> <li><a href="/wiki/Soot" title="Soot">Soot</a></li> <li><a href="/wiki/Volatile_organic_compound" title="Volatile organic compound">Volatile organic compound</a></li></ul></div></div></td> </tr><tr><td class="sidebar-content" style="padding-top:0.1em;"> <div class="sidebar-list mw-collapsible mw-collapsed"><div class="sidebar-list-title" style="background:#fadcc5;text-align:center;;color: var(--color-base)"><a href="/wiki/Biological_pollution" title="Biological pollution">Biological</a></div><div class="sidebar-list-content mw-collapsible-content"> <ul><li><a href="/wiki/Biological_hazard" title="Biological hazard">Biological hazard</a></li> <li><a href="/wiki/Genetic_pollution" title="Genetic pollution">Genetic</a></li> <li><a href="/wiki/Illegal_logging" title="Illegal logging">Illegal logging</a></li> <li><a href="/wiki/Introduced_species" title="Introduced species">Introduced species</a> <ul><li><a href="/wiki/Invasive_species" title="Invasive species">Invasive species</a></li></ul></li></ul></div></div></td> </tr><tr><td class="sidebar-content" style="padding-top:0.1em;"> <div class="sidebar-list mw-collapsible mw-collapsed"><div class="sidebar-list-title" style="background:#fadcc5;text-align:center;;color: var(--color-base)">Digital</div><div class="sidebar-list-content mw-collapsible-content"> <ul><li><a href="/wiki/Information_pollution" title="Information pollution">Information</a></li></ul></div></div></td> </tr><tr><td class="sidebar-content" style="padding-top:0.1em;"> <div class="sidebar-list mw-collapsible mw-collapsed"><div class="sidebar-list-title" style="background:#fadcc5;text-align:center;;color: var(--color-base)"><a href="/wiki/Electromagnetic_radiation_and_health" title="Electromagnetic radiation and health">Electromagnetic</a></div><div class="sidebar-list-content mw-collapsible-content"> <ul><li><a href="/wiki/Light_pollution" title="Light pollution">Light</a> <ul><li><a href="/wiki/Ecological_light_pollution" title="Ecological light pollution">Ecological</a></li> <li><a href="/wiki/Overillumination" class="mw-redirect" title="Overillumination">Overillumination</a></li></ul></li> <li><a href="/wiki/Radio_spectrum_pollution" title="Radio spectrum pollution">Radio spectrum</a></li></ul></div></div></td> </tr><tr><td class="sidebar-content" style="padding-top:0.1em;"> <div class="sidebar-list mw-collapsible mw-collapsed"><div class="sidebar-list-title" style="background:#fadcc5;text-align:center;;color: var(--color-base)">Natural</div><div class="sidebar-list-content mw-collapsible-content"> <ul><li><a href="/wiki/Ozone" title="Ozone">Ozone</a></li> <li><a href="/wiki/Radium_and_radon_in_the_environment" title="Radium and radon in the environment">Radium and radon in the environment</a></li> <li><a href="/wiki/Volcanic_ash" title="Volcanic ash">Volcanic ash</a></li> <li><a href="/wiki/Wildfire" title="Wildfire">Wildfire</a></li></ul></div></div></td> </tr><tr><td class="sidebar-content" style="padding-top:0.1em;"> <div class="sidebar-list mw-collapsible mw-collapsed"><div class="sidebar-list-title" style="background:#fadcc5;text-align:center;;color: var(--color-base)"><a href="/wiki/Noise_pollution" title="Noise pollution">Noise</a></div><div class="sidebar-list-content mw-collapsible-content"> <ul><li><a href="/wiki/Environmental_effects_of_transport" class="mw-redirect" title="Environmental effects of transport">Transportation</a></li> <li><a href="/wiki/Health_effects_from_noise" title="Health effects from noise">Health effects from noise</a></li> <li><a href="/wiki/Marine_mammals_and_sonar" title="Marine mammals and sonar">Marine mammals and sonar</a></li> <li><a href="/wiki/Noise_barrier" title="Noise barrier">Noise barrier</a></li> <li><a href="/wiki/Noise_control" title="Noise control">Noise control</a></li> <li><a href="/wiki/Soundproofing" title="Soundproofing">Soundproofing</a></li></ul></div></div></td> </tr><tr><td class="sidebar-content" style="padding-top:0.1em;"> <div class="sidebar-list mw-collapsible mw-collapsed"><div class="sidebar-list-title" style="background:#fadcc5;text-align:center;;color: var(--color-base)"><a href="/wiki/Radioactive_contamination" title="Radioactive contamination">Radiation</a></div><div class="sidebar-list-content mw-collapsible-content"> <ul><li><a href="/wiki/Actinides_in_the_environment" title="Actinides in the environment">Actinides</a></li> <li><a href="/wiki/Bioremediation_of_radioactive_waste" title="Bioremediation of radioactive waste">Bioremediation</a></li> <li><a href="/wiki/Depleted_uranium" title="Depleted uranium">Depleted uranium</a></li> <li><a href="/wiki/Nuclear_fission_product" title="Nuclear fission product">Nuclear fission</a></li> <li><a href="/wiki/Nuclear_fallout" title="Nuclear fallout">Nuclear fallout</a></li> <li><a href="/wiki/Plutonium_in_the_environment" title="Plutonium in the environment">Plutonium</a></li> <li><a href="/wiki/Acute_radiation_syndrome" title="Acute radiation syndrome">Poisoning</a></li> <li><a href="/wiki/Environmental_radioactivity" title="Environmental radioactivity">Radioactivity</a></li> <li><a href="/wiki/Uranium_in_the_environment" title="Uranium in the environment">Uranium</a></li> <li><a href="/wiki/Radioactive_waste" title="Radioactive waste">Radioactive waste</a></li></ul></div></div></td> </tr><tr><td class="sidebar-content" style="padding-top:0.1em;"> <div class="sidebar-list mw-collapsible mw-collapsed"><div class="sidebar-list-title" style="background:#fadcc5;text-align:center;;color: var(--color-base)"><a href="/wiki/Soil_contamination" title="Soil contamination">Soil</a></div><div class="sidebar-list-content mw-collapsible-content"> <ul><li><a href="/wiki/Agricultural_pollution" title="Agricultural pollution">Agricultural</a></li> <li><a href="/wiki/Land_degradation" title="Land degradation">Land degradation</a></li> <li><a href="/wiki/Bioremediation" title="Bioremediation">Bioremediation</a></li> <li><a href="/wiki/Open_defecation" title="Open defecation">Defecation</a></li> <li><a href="/wiki/Electrical_resistance_heating" title="Electrical resistance heating">Electrical resistance heating</a></li> <li><a href="/wiki/Illegal_mining" title="Illegal mining">Illegal mining</a></li> <li><a href="/wiki/Soil_guideline_value" title="Soil guideline value">Soil guideline values</a></li> <li><a href="/wiki/Phytoremediation" title="Phytoremediation">Phytoremediation</a></li></ul></div></div></td> </tr><tr><td class="sidebar-content" style="padding-top:0.1em;"> <div class="sidebar-list mw-collapsible mw-collapsed"><div class="sidebar-list-title" style="background:#fadcc5;text-align:center;;color: var(--color-base)">Solid waste</div><div class="sidebar-list-content mw-collapsible-content"> <ul><li><a href="/wiki/Advertising_mail" title="Advertising mail">Advertising mail</a></li> <li><a href="/wiki/Biodegradable_waste" title="Biodegradable waste">Biodegradable waste</a></li> <li><a href="/wiki/Brown_waste" title="Brown waste">Brown waste</a></li> <li><a href="/wiki/Electronic_waste" title="Electronic waste">Electronic waste</a></li> <li><a href="/wiki/Foam_food_container" title="Foam food container">Foam food container</a></li> <li><a href="/wiki/Food_loss_and_waste" title="Food loss and waste">Food waste</a></li> <li><a href="/wiki/Green_waste" title="Green waste">Green waste</a></li> <li><a href="/wiki/Hazardous_waste" title="Hazardous waste">Hazardous waste</a></li> <li><a href="/wiki/Industrial_waste" title="Industrial waste">Industrial waste</a></li> <li><a href="/wiki/Litter" title="Litter">Litter</a></li> <li><a href="/wiki/Environmental_effects_of_mining" class="mw-redirect" title="Environmental effects of mining">Mining</a></li> <li><a href="/wiki/Municipal_solid_waste" title="Municipal solid waste">Municipal solid waste</a></li> <li><a href="/wiki/Pollution_from_nanomaterials" title="Pollution from nanomaterials">Nanomaterials</a></li> <li><a href="/wiki/Plastic_pollution" title="Plastic pollution">Plastic</a></li> <li><a href="/wiki/Packaging_waste" title="Packaging waste">Packaging waste</a></li> <li><a href="/wiki/Post-consumer_waste" title="Post-consumer waste">Post-consumer waste</a></li> <li><a href="/wiki/Waste_management" title="Waste management">Waste management</a></li></ul></div></div></td> </tr><tr><td class="sidebar-content" style="padding-top:0.1em;"> <div class="sidebar-list mw-collapsible mw-collapsed"><div class="sidebar-list-title" style="background:#fadcc5;text-align:center;;color: var(--color-base)">Space</div><div class="sidebar-list-content mw-collapsible-content"> <ul><li><a href="/wiki/Space_debris" title="Space debris">Space debris</a></li></ul></div></div></td> </tr><tr><td class="sidebar-content" style="padding-top:0.1em;"> <div class="sidebar-list mw-collapsible mw-collapsed"><div class="sidebar-list-title" style="background:#fadcc5;text-align:center;;color: var(--color-base)"><a href="/wiki/Thermal_pollution" title="Thermal pollution">Thermal</a></div><div class="sidebar-list-content mw-collapsible-content"> <ul><li><a href="/wiki/Urban_heat_island" title="Urban heat island">Urban heat island</a></li></ul></div></div></td> </tr><tr><td class="sidebar-content" style="padding-top:0.1em;"> <div class="sidebar-list mw-collapsible mw-collapsed"><div class="sidebar-list-title" style="background:#fadcc5;text-align:center;;color: var(--color-base)"><a href="/wiki/Visual_pollution" title="Visual pollution">Visual</a></div><div class="sidebar-list-content mw-collapsible-content"> <ul><li><a href="/wiki/Air_travel" title="Air travel">Air travel</a></li> <li><a href="/wiki/Clutter_(advertising)" title="Clutter (advertising)">Advertising clutter</a></li> <li><a href="/wiki/Overhead_power_line" title="Overhead power line">Overhead power lines</a></li> <li><a href="/wiki/Traffic_sign" title="Traffic sign">Traffic signs</a></li> <li><a href="/wiki/Vandalism" title="Vandalism">Vandalism</a></li></ul></div></div></td> </tr><tr><td class="sidebar-content" style="padding-top:0.1em;"> <div class="sidebar-list mw-collapsible mw-collapsed"><div class="sidebar-list-title" style="background:#fadcc5;text-align:center;;color: var(--color-base)"><a href="/wiki/Environmental_impact_of_war" title="Environmental impact of war">War</a></div><div class="sidebar-list-content mw-collapsible-content"> <ul><li><a href="/wiki/Chemical_warfare" title="Chemical warfare">Chemical warfare</a></li> <li><a href="/wiki/Herbicidal_warfare" title="Herbicidal warfare">Herbicidal warfare</a> <ul><li><a href="/wiki/Agent_Orange" title="Agent Orange">Agent Orange</a></li></ul></li> <li><a href="/wiki/Nuclear_holocaust" title="Nuclear holocaust">Nuclear holocaust</a> <ul><li><a href="/wiki/Nuclear_fallout" title="Nuclear fallout">Nuclear fallout</a></li> <li><a href="/wiki/Nuclear_famine" title="Nuclear famine">Nuclear famine</a></li> <li><a href="/wiki/Nuclear_winter" title="Nuclear winter">Nuclear winter</a></li></ul></li> <li><a href="/wiki/Scorched_earth" title="Scorched earth">Scorched earth</a></li> <li><a href="/wiki/Unexploded_ordnance" title="Unexploded ordnance">Unexploded ordnance</a></li> <li><a href="/wiki/War_and_environmental_law" title="War and environmental law">War and environmental law</a></li></ul></div></div></td> </tr><tr><td class="sidebar-content" style="padding-top:0.1em;"> <div class="sidebar-list mw-collapsible mw-collapsed"><div class="sidebar-list-title" style="background:#fadcc5;text-align:center;;color: var(--color-base)"><a href="/wiki/Water_pollution" title="Water pollution">Water</a></div><div class="sidebar-list-content mw-collapsible-content"> <ul><li><a href="/wiki/Agricultural_wastewater_treatment" title="Agricultural wastewater treatment">Agricultural wastewater</a></li> <li><a href="/wiki/Biosolids" title="Biosolids">Biosolids</a></li> <li><a href="/wiki/Waterborne_diseases" class="mw-redirect" title="Waterborne diseases">Diseases</a></li> <li><a href="/wiki/Eutrophication" title="Eutrophication">Eutrophication</a></li> <li><a href="/wiki/Firewater_(fire_fighting)" title="Firewater (fire fighting)">Firewater</a></li> <li><a href="/wiki/Freshwater_environmental_quality_parameters" title="Freshwater environmental quality parameters">Freshwater</a></li> <li><a href="/wiki/Groundwater_pollution" title="Groundwater pollution">Groundwater</a></li> <li><a href="/wiki/Hypoxia_(environmental)" title="Hypoxia (environmental)">Hypoxia</a></li> <li><a href="/wiki/Industrial_wastewater_treatment" title="Industrial wastewater treatment">Industrial wastewater</a></li> <li><a href="/wiki/Marine_pollution" title="Marine pollution">Marine</a></li> <li><a href="/wiki/Environmental_monitoring" title="Environmental monitoring">Monitoring</a></li> <li><a href="/wiki/Nonpoint_source_pollution" title="Nonpoint source pollution">Nonpoint source</a></li> <li><a href="/wiki/Nutrient_pollution" title="Nutrient pollution">Nutrient</a></li> <li><a href="/wiki/Ocean_acidification" title="Ocean acidification">Ocean acidification</a></li> <li><a href="/wiki/Oil_spill" title="Oil spill">Oil spill</a></li> <li><a href="/wiki/Environmental_impact_of_pharmaceuticals_and_personal_care_products" title="Environmental impact of pharmaceuticals and personal care products">Pharmaceuticals</a></li> <li><a href="/wiki/Freshwater_salinization" title="Freshwater salinization">Freshwater salinization</a></li> <li><a href="/wiki/Septic_tank" title="Septic tank">Septic tanks</a></li> <li><a href="/wiki/Sewage" title="Sewage">Sewage</a></li> <li><a href="/wiki/Environmental_effects_of_shipping" class="mw-redirect" title="Environmental effects of shipping">Shipping</a></li> <li><a href="/wiki/Sludge" title="Sludge">Sludge</a></li> <li><a href="/wiki/Water_stagnation" title="Water stagnation">Stagnation</a></li> <li><a href="/wiki/Sulfur_water" title="Sulfur water">Sulfur water</a></li> <li><a href="/wiki/Surface_runoff" title="Surface runoff">Surface runoff</a></li> <li><a href="/wiki/Turbidity" title="Turbidity">Turbidity</a></li> <li><a href="/wiki/Urban_runoff" title="Urban runoff">Urban runoff</a></li> <li><a href="/wiki/Water_quality" title="Water quality">Water quality</a></li> <li><a href="/wiki/Wastewater" title="Wastewater">Wastewater</a></li></ul></div></div></td> </tr><tr><td class="sidebar-content" style="padding-top:0.1em;"> <div class="sidebar-list mw-collapsible mw-collapsed"><div class="sidebar-list-title" style="background:#fadcc5;text-align:center;;color: var(--color-base)">Topics</div><div class="sidebar-list-content mw-collapsible-content"> <ul><li><a href="/wiki/History_of_environmental_pollution" title="History of environmental pollution">History</a></li> <li><a href="/wiki/Pollutant" title="Pollutant">Pollutants</a> <ul><li><a href="/wiki/Heavy_metals" class="mw-redirect" title="Heavy metals">Heavy metals</a></li> <li><a href="/wiki/Paint" title="Paint">Paint</a></li></ul></li></ul></div></div></td> </tr><tr><td class="sidebar-content-with-subgroup" style="padding-top:0.1em;"> <div class="sidebar-list mw-collapsible mw-collapsed"><div class="sidebar-list-title" style="background:#fadcc5;text-align:center;;color: var(--color-base)">Misc</div><div class="sidebar-list-content mw-collapsible-content"> <ul><li><a href="/wiki/Area_source_pollution" title="Area source pollution">Area source</a></li> <li><a href="/wiki/Brain_health_and_pollution" title="Brain health and pollution">Brain health and pollution</a></li> <li><a href="/wiki/Debris" title="Debris">Debris</a></li> <li><a href="/wiki/Dust" title="Dust">Dust</a></li> <li><a href="/wiki/Garbology" title="Garbology">Garbology</a></li> <li><a href="/wiki/Legacy_pollution" title="Legacy pollution">Legacy</a></li> <li><a href="/wiki/Midden" title="Midden">Midden</a></li> <li><a href="/wiki/Point_source_pollution" title="Point source pollution">Point source</a></li> <li><a href="/wiki/Waste" title="Waste">Waste</a> <ul><li><a href="/wiki/Toxic_waste" title="Toxic waste">Toxic</a></li></ul></li></ul> <table class="sidebar-subgroup"><tbody><tr><th class="sidebar-heading"> Lists</th></tr><tr><td class="sidebar-content"> <ul><li><a href="/wiki/List_of_pollution-related_diseases" title="List of pollution-related diseases">Diseases</a></li> <li><a href="/wiki/List_of_environmental_laws_by_country" title="List of environmental laws by country">Law by country</a></li> <li><a href="/wiki/List_of_most-polluted_cities_by_particulate_matter_concentration" title="List of most-polluted cities by particulate matter concentration">Most polluted cities</a></li> <li><a href="/wiki/List_of_least_polluted_cities_by_particulate_matter_concentration" class="mw-redirect" title="List of least polluted cities by particulate matter concentration">Least polluted cities by PM2.5</a></li> <li><a href="/wiki/List_of_international_environmental_agreements" title="List of international environmental agreements">Treaties</a></li></ul></td> </tr><tr><th class="sidebar-heading"> Categories</th></tr><tr><td class="sidebar-content"> <ul><li><a href="/wiki/Category:Pollution_by_country" title="Category:Pollution by country">By country</a></li></ul></td> </tr></tbody></table></div></div></td> </tr><tr><td class="sidebar-below" style="border-top:1px solid #aaa;border-bottom:1px solid #aaa;"> <ul><li><span class="nowrap"><span class="noviewer" typeof="mw:File"><a href="/wiki/File:Aegopodium_podagraria1_ies.jpg" class="mw-file-description"><img alt="icon" src="//upload.wikimedia.org/wikipedia/commons/thumb/b/bf/Aegopodium_podagraria1_ies.jpg/16px-Aegopodium_podagraria1_ies.jpg" decoding="async" width="16" height="14" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/bf/Aegopodium_podagraria1_ies.jpg/24px-Aegopodium_podagraria1_ies.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/bf/Aegopodium_podagraria1_ies.jpg/32px-Aegopodium_podagraria1_ies.jpg 2x" data-file-width="800" data-file-height="700" /></a></span> </span><a href="/wiki/Portal:Environment" title="Portal:Environment">Environment portal</a></li> <li><span class="nowrap"><span class="mw-image-border noviewer" typeof="mw:File"><span><img alt="icon" src="//upload.wikimedia.org/wikipedia/commons/thumb/6/6a/Earth_Day_Flag.png/16px-Earth_Day_Flag.png" decoding="async" width="16" height="11" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/6/6a/Earth_Day_Flag.png/24px-Earth_Day_Flag.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/6/6a/Earth_Day_Flag.png/32px-Earth_Day_Flag.png 2x" data-file-width="6000" data-file-height="4000" /></span></span> </span><a href="/wiki/Portal:Ecology" title="Portal:Ecology">Ecology portal</a></li></ul></td></tr><tr><td class="sidebar-navbar"><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:Pollution_sidebar" title="Template:Pollution sidebar"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Pollution_sidebar" title="Template talk:Pollution sidebar"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Pollution_sidebar" title="Special:EditPage/Template:Pollution sidebar"><abbr title="Edit this template">e</abbr></a></li></ul></div></td></tr></tbody></table> <p>An <b>air quality index</b> (AQI) is an indicator developed by government agencies<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> to communicate to the public how <a href="/wiki/Air_pollution" title="Air pollution">polluted</a> the air currently is or how polluted it is forecast to become.<sup id="cite_ref-create-clean-room_2-0" class="reference"><a href="#cite_note-create-clean-room-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> As air pollution levels rise, so does the AQI, along with the associated public health risk. Children, the elderly and individuals with respiratory or cardiovascular problems are typically the first groups affected by poor air quality. When the AQI is high, governmental bodies generally encourage people to reduce physical activity outdoors, or even avoid going out altogether. When <a href="/wiki/Wildfire" title="Wildfire">wildfires</a> result in a high AQI, the use of a mask (such as an <a href="/wiki/N95_respirator" title="N95 respirator">N95 respirator</a>) outdoors and an air purifier (incorporating both <a href="/wiki/HEPA_filter" class="mw-redirect" title="HEPA filter">HEPA</a> and <a href="/wiki/Activated_carbon" title="Activated carbon">activated carbon</a> filters) indoors are also encouraged.<sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> </p><p>Different countries have their <a href="#Indices_by_location">own air quality indices</a>, corresponding to different national air quality standards. Some of these are Canada's <a href="/wiki/Air_Quality_Health_Index_(Canada)" title="Air Quality Health Index (Canada)">Air Quality Health Index</a>, Malaysia's <a href="/wiki/Air_Pollution_Index" title="Air Pollution Index">Air Pollution Index</a>, and Singapore's <a href="/wiki/Pollutant_Standards_Index" title="Pollutant Standards Index">Pollutant Standards Index</a>. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Overview">Overview</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Air_quality_index&action=edit&section=1" title="Edit section: Overview"><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:Edinburgh_air_quality_measurement_station_dsc06786.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/a/a1/Edinburgh_air_quality_measurement_station_dsc06786.jpg/220px-Edinburgh_air_quality_measurement_station_dsc06786.jpg" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/a/a1/Edinburgh_air_quality_measurement_station_dsc06786.jpg/330px-Edinburgh_air_quality_measurement_station_dsc06786.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/a/a1/Edinburgh_air_quality_measurement_station_dsc06786.jpg/440px-Edinburgh_air_quality_measurement_station_dsc06786.jpg 2x" data-file-width="2592" data-file-height="1944" /></a><figcaption>An air quality measurement station in <a href="/wiki/Edinburgh" title="Edinburgh">Edinburgh</a>, Scotland</figcaption></figure> <p>Computation of the AQI requires an air <a href="/wiki/Measures_of_pollutant_concentration" title="Measures of pollutant concentration">pollutant concentration</a> over a specified averaging period, obtained from an <a href="/wiki/Environmental_monitoring#Air_quality_monitoring" title="Environmental monitoring">air monitor</a> or <a href="/wiki/Atmospheric_dispersion_modeling" title="Atmospheric dispersion modeling">model</a>. Taken together, concentration and time represent the <a href="/wiki/Dose_response" class="mw-redirect" title="Dose response">dose</a> of the air pollutant. Health effects corresponding to a given dose are established by epidemiological research.<sup id="cite_ref-6" class="reference"><a href="#cite_note-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> Air pollutants vary in potency, and the function used to convert from air pollutant concentration to AQI varies by pollutant. Its air quality index values are typically grouped into ranges. Each range is assigned a descriptor, a color code, and a standardized public health advisory. </p><p>The AQI can increase due to an increase of air emissions. For example, during rush hour traffic or when there is an upwind forest fire or from a lack of dilution of air pollutants. <a href="/wiki/Air_stagnation" title="Air stagnation">Stagnant air</a>, often caused by an <a href="/wiki/Anticyclone" title="Anticyclone">anticyclone</a>, <a href="/wiki/Temperature_inversion" class="mw-redirect" title="Temperature inversion">temperature inversion</a>, or low <a href="/wiki/Wind" title="Wind">wind</a> speeds lets air pollution remain in a local area, leading to high concentrations of pollutants, chemical reactions between air contaminants and <a href="/wiki/Haze" title="Haze">hazy</a> conditions.<sup id="cite_ref-7" class="reference"><a href="#cite_note-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> </p> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:SignboardAirQualityHouston.JPG" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/1/18/SignboardAirQualityHouston.JPG/220px-SignboardAirQualityHouston.JPG" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/18/SignboardAirQualityHouston.JPG/330px-SignboardAirQualityHouston.JPG 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/18/SignboardAirQualityHouston.JPG/440px-SignboardAirQualityHouston.JPG 2x" data-file-width="2272" data-file-height="1704" /></a><figcaption>Signboard in <a href="/wiki/Gulfton,_Houston" title="Gulfton, Houston">Gulfton, Houston</a>, Texas, indicating an <a href="/wiki/Ozone" title="Ozone">ozone</a> watch</figcaption></figure> <p>On a day when the AQI is predicted to be elevated due to fine particle pollution, an agency or public health organization might: </p> <ul><li>advise sensitive groups, such as the elderly, children and those with respiratory or cardiovascular problems or suffering from diseases, to avoid outdoor exertion.<sup id="cite_ref-8" class="reference"><a href="#cite_note-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup></li> <li>declare an "action day" to encourage voluntary measures to curtail air emissions, such as using public transportation.<sup id="cite_ref-9" class="reference"><a href="#cite_note-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup></li> <li>recommend the use of masks outdoors and air purifiers indoors to prevent fine particles from entering the lungs.<sup id="cite_ref-10" class="reference"><a href="#cite_note-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup></li></ul> <p>During a period of very poor air quality, such as an <a href="/wiki/Air_pollution_episode" title="Air pollution episode">air pollution episode</a>, when the AQI indicates that acute exposure may cause significant harm to the public health, agencies may invoke emergency plans that allow them to order major emitters (such as coal burning industries) to curtail emissions until the hazardous conditions abate.<sup id="cite_ref-11" class="reference"><a href="#cite_note-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> </p><p>Most air contaminants do not have an associated AQI. Many countries monitor <a href="/wiki/Ground-level_ozone" title="Ground-level ozone">ground-level ozone</a>, <a href="/wiki/Atmospheric_particulate_matter" class="mw-redirect" title="Atmospheric particulate matter">particulates</a>, <a href="/wiki/Sulfur_dioxide" title="Sulfur dioxide">sulfur dioxide</a>, <a href="/wiki/Carbon_monoxide" title="Carbon monoxide">carbon monoxide</a> and <a href="/wiki/Nitrogen_dioxide" title="Nitrogen dioxide">nitrogen dioxide</a>, and calculate air quality indices for these pollutants.<sup id="cite_ref-aqi_basic_12-0" class="reference"><a href="#cite_note-aqi_basic-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup> </p><p>The definition of the AQI in a particular nation reflects the discourse surrounding the development of national air quality standards in that nation.<sup id="cite_ref-13" class="reference"><a href="#cite_note-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup> A website allowing government agencies anywhere in the world to submit their real-time air monitoring data for display using a common definition of the air quality index has recently become available.<sup id="cite_ref-14" class="reference"><a href="#cite_note-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Indices_by_location">Indices by location</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Air_quality_index&action=edit&section=2" title="Edit section: Indices by location"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading3"><h3 id="Australia">Australia</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Air_quality_index&action=edit&section=3" title="Edit section: Australia"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Each of the <a href="/wiki/States_and_territories_of_Australia" title="States and territories of Australia">states and territories of Australia</a> is responsible for monitoring air quality and publishing data in accordance with the National Environment Protection (Ambient Air Quality) Measure (NEPM) standards.<sup id="cite_ref-15" class="reference"><a href="#cite_note-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup> </p><p>Each state and territory publishes air quality data for individual monitoring locations, and most states and territories publish air quality indexes for each monitoring location. </p><p>Across Australia, a consistent approach is taken with air quality indexes, using a simple linear scale where 100 represents the maximum concentration standard for each pollutant, as set by the NEPM. These maximum concentration standards are: </p> <table class="wikitable"> <tbody><tr> <th>Pollutant </th> <th>Averaging period </th> <th>Maximum concentration standard </th></tr> <tr> <td>Carbon monoxide </td> <td>8 hours </td> <td>9 ppm </td></tr> <tr> <td rowspan="2">Nitrogen dioxide </td> <td>1 hour </td> <td>0.12 ppm </td></tr> <tr> <td>1 year </td> <td>0.03 ppm </td></tr> <tr> <td rowspan="2">Ozone </td> <td>1 hour </td> <td>0.10 ppm </td></tr> <tr> <td>4 hours </td> <td>0.08 ppm </td></tr> <tr> <td rowspan="3">Sulfur dioxide </td> <td>1 hour </td> <td>0.20 ppm </td></tr> <tr> <td>1 day </td> <td>0.08 ppm </td></tr> <tr> <td>1 year </td> <td>0.02 ppm </td></tr> <tr> <td>Lead </td> <td>1 year </td> <td>0.50 μg/m<sup>3</sup> </td></tr> <tr> <td rowspan="2">PM 10 </td> <td>1 day </td> <td>50 μg/m<sup>3</sup> </td></tr> <tr> <td>1 year </td> <td>25 μg/m<sup>3</sup> </td></tr> <tr> <td rowspan="2">PM 2.5 </td> <td>1 day </td> <td>25 μg/m<sup>3</sup> </td></tr> <tr> <td>1 year </td> <td>8 μg/m<sup>3</sup> </td></tr></tbody></table> <p>The air quality index (AQI) for an individual location is simply the highest of the air quality index values for each pollutant being monitored at that location. </p><p>There are six AQI bands, with health advice for each: </p> <table class="wikitable"> <tbody><tr> <th>AQI </th> <th>Category </th> <th>Health advice </th></tr> <tr> <td style="text-align:center;">0-33 </td> <td style="text-align:center; background:#338ce7;color:#000">Very Good </td> <td>Enjoy activities </td></tr> <tr> <td style="text-align:center;">34-66 </td> <td style="text-align:center; background:#37b13c;color:#000">Good </td> <td>Enjoy activities </td></tr> <tr> <td style="text-align:center;">67-99 </td> <td style="text-align:center; background:#e8dd28;color:#000">Fair </td> <td>People unusually sensitive to air pollution: Plan strenuous outdoor activities when air quality is better </td></tr> <tr> <td style="text-align:center;">100-149 </td> <td style="text-align:center; background:#f06520;color:#000">Poor </td> <td>Sensitive groups: Cut back or reschedule strenuous outdoor activities </td></tr> <tr> <td style="text-align:center;">150-200 </td> <td style="text-align:center; background:#8e1b66;color:#fff">Very Poor </td> <td>Sensitive groups: Avoid strenuous outdoor activities <p>Everyone: Cut back or reschedule strenuous outdoor activities </p> </td></tr> <tr> <td style="text-align:center;">200+ </td> <td style="text-align:center; background:#c51515;color:#fff">Hazardous </td> <td>Sensitive groups: Avoid all outdoor physical activities <p>Everyone: Significantly cut back on outdoor physical activities </p> </td></tr></tbody></table> <div class="mw-heading mw-heading3"><h3 id="Canada">Canada</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Air_quality_index&action=edit&section=4" title="Edit section: Canada"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></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">Main article: <a href="/wiki/Air_Quality_Health_Index_(Canada)" title="Air Quality Health Index (Canada)">Air Quality Health Index (Canada)</a></div> <p>Air quality in Canada has been reported for many years with provincial air quality indices (AQIs). Significantly, AQI values reflect air quality management objectives, which are based on the lowest achievable emissions rate, rather than exclusive concern for human health. The <a href="/wiki/Air_Quality_Health_Index_(Canada)" title="Air Quality Health Index (Canada)">Air Quality Health Index</a> (AQHI) is a scale designed to help understand the impact of air quality on health. It is a health protection tool used to make decisions to reduce short-term exposure to air pollution by adjusting activity levels during increased levels of air pollution. The Air Quality Health Index also provides advice on how to improve air quality by proposing a behavioral change to reduce the environmental footprint. This index pays particular attention to people who are sensitive to air pollution. It provides them with advice on how to protect their health during air quality levels associated with <i>low</i>, <i>moderate</i>, <i>high</i> and <i>very high</i> health risks. </p><p>The AQHI provides a number from 1 to 10+ to indicate the level of health risk associated with local air quality. On occasion, when the amount of air pollution is abnormally high, the number may exceed 10. The AQHI provides a local air quality current value as well as a local air quality maximums forecast for today, tonight, and tomorrow, and provides associated health advice.<sup id="cite_ref-16" class="reference"><a href="#cite_note-16"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup> </p> <table class="wikitable"> <tbody><tr> <th rowspan="2">Health risk </th> <th rowspan="2">Air quality health index </th> <th colspan="2">Health messages </th></tr> <tr> <th>At risk population</th> <th>General population </th></tr> <tr> <td style="text-align:center; background:#00ccff;color:#000">Low Risk</td> <td style="text-align:center; background:#00ccff;color:#000">1-3</td> <td><b>Enjoy</b> your usual outdoor activities.</td> <td><b>Ideal</b> air quality for outdoor activities. </td></tr> <tr> <td style="text-align:center; background:#ffff00;color:#000">Moderate Risk</td> <td style="text-align:center; background:#ffff00;color:#000">4-6</td> <td><b>Consider</b> reducing or rescheduling strenuous activities outdoors if you are experiencing symptoms.</td> <td><b>No need to modify</b> your usual outdoor activities unless you experience symptoms such as coughing and throat irritation. </td></tr> <tr> <td style="text-align:center; background:#ff6666;color:#000">High Risk</td> <td style="text-align:center; background:#ff6666;color:#000">7-10</td> <td><b>Reduce or reschedule</b> strenuous activities outdoors. Children and the elderly should also take it easy.</td> <td><b>Consider</b> reducing or rescheduling strenuous activities outdoors if you experience symptoms such as coughing and throat irritation. </td></tr> <tr> <td style="text-align:center; background:#660000;color:#fff">Very High Risk</td> <td style="text-align:center; background:#660000;color:#fff">Above 10</td> <td><b>Avoid</b> strenuous activities outdoors. Children and the elderly should also avoid outdoor physical exertion.</td> <td><b>Reduce or reschedule</b> strenuous activities outdoors, especially if you experience symptoms such as coughing and throat irritation. </td></tr></tbody></table> <div class="mw-heading mw-heading3"><h3 id="China">China</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Air_quality_index&action=edit&section=5" title="Edit section: China"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading4"><h4 id="Hong_Kong">Hong Kong</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Air_quality_index&action=edit&section=6" title="Edit section: Hong Kong"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>On December 30, 2013, <a href="/wiki/Hong_Kong" title="Hong Kong">Hong Kong</a> replaced the <a href="/wiki/Air_Pollution_Index#Hong_Kong" title="Air Pollution Index">Air Pollution Index</a> with a new index called the <i>Air Quality Health Index</i>.<sup id="cite_ref-17" class="reference"><a href="#cite_note-17"><span class="cite-bracket">[</span>17<span class="cite-bracket">]</span></a></sup> This index, reported by the <a href="/wiki/Environmental_Protection_Department" title="Environmental Protection Department">Environmental Protection Department</a>, is measured on a scale of 1 to 10+ and considers four air pollutants: ozone; nitrogen dioxide; sulfur dioxide and particulate matter (including PM10 and PM2.5). For any given hour the AQHI is calculated from the sum of the percentage excess risk of daily hospital admissions attributable to the 3-hour moving average concentrations of these four pollutants. The AQHIs are grouped into five AQHI health risk categories with health advice provided:<sup id="cite_ref-18" class="reference"><a href="#cite_note-18"><span class="cite-bracket">[</span>18<span class="cite-bracket">]</span></a></sup> </p> <table class="wikitable"> <tbody><tr> <th>Health Risk</th> <th>AQHI </th></tr> <tr> <td rowspan="3" style="text-align:center; background:#4db748;color:#000">Low </td> <td>1 </td></tr> <tr> <td>2 </td></tr> <tr> <td>3 </td></tr> <tr> <td rowspan="3" style="text-align:center; background:#f9a61a;color:#000">Moderate </td> <td>4 </td></tr> <tr> <td>5 </td></tr> <tr> <td>6 </td></tr> <tr> <td style="text-align:center; background:#ed1b24;color:#fff">High</td> <td>7 </td></tr> <tr> <td rowspan="3" style="text-align:center; background:#9f4721;color:#fff">Very High </td> <td>8 </td></tr> <tr> <td>9 </td></tr> <tr> <td>10 </td></tr> <tr> <td style="text-align:center; background:#000000;color:#fff">Serious</td> <td>10+ </td></tr> </tbody></table> <div class="mw-heading mw-heading4"><h4 id="Mainland_China">Mainland China</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Air_quality_index&action=edit&section=7" title="Edit section: Mainland China"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>China's Ministry of Environmental Protection (<a href="/wiki/Ministry_of_Environmental_Protection_of_the_People%27s_Republic_of_China" class="mw-redirect" title="Ministry of Environmental Protection of the People's Republic of China">MEP</a>) is responsible for measuring the level of <a href="/wiki/Air_pollution_in_China" class="mw-redirect" title="Air pollution in China">air pollution in China</a>. As of January 1, 2013, MEP monitors daily pollution level in 163 of its major cities. The AQI level is based on the level of six atmospheric pollutants, namely <a href="/wiki/Sulfur_dioxide" title="Sulfur dioxide">sulfur dioxide</a> (SO<sub>2</sub>), <a href="/wiki/Nitrogen_dioxide" title="Nitrogen dioxide">nitrogen dioxide</a> (NO<sub>2</sub>), suspended particulates smaller than 10 μm in <a href="/wiki/Aerodynamic_diameter" class="mw-redirect" title="Aerodynamic diameter">aerodynamic diameter</a> (PM<sub>10</sub>),<sup id="cite_ref-:0_19-0" class="reference"><a href="#cite_note-:0-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup> suspended particulates smaller than 2.5 μm in <a href="/wiki/Aerodynamic_diameter" class="mw-redirect" title="Aerodynamic diameter">aerodynamic diameter</a> (PM<sub>2.5</sub>),<sup id="cite_ref-:0_19-1" class="reference"><a href="#cite_note-:0-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup> <a href="/wiki/Carbon_monoxide" title="Carbon monoxide">carbon monoxide</a> (CO), and <a href="/wiki/Ozone" title="Ozone">ozone</a> (O<sub>3</sub>) measured at the monitoring stations throughout each city.<sup id="cite_ref-sepa.gov.cn_20-0" class="reference"><a href="#cite_note-sepa.gov.cn-20"><span class="cite-bracket">[</span>20<span class="cite-bracket">]</span></a></sup> </p> <dl><dt>AQI mechanics</dt></dl> <p>An individual score (Individual Air Quality Index, IAQI) is calculated using breakpoint concentrations below, and using same piecewise linear function to calculate intermediate values as the US AQI scale. and The final AQI value can be calculated either per hour or per 24 hours and is <i>the max</i> of these six scores.<sup id="cite_ref-sepa.gov.cn_20-1" class="reference"><a href="#cite_note-sepa.gov.cn-20"><span class="cite-bracket">[</span>20<span class="cite-bracket">]</span></a></sup> </p> <table class="wikitable"> <caption>Chinese AQI category and pollutant breakpoints <sup id="cite_ref-sepa.gov.cn_20-2" class="reference"><a href="#cite_note-sepa.gov.cn-20"><span class="cite-bracket">[</span>20<span class="cite-bracket">]</span></a></sup> </caption> <tbody><tr> <th>Individual index </th> <th colspan="10">Units are in μg/m<sup>3</sup> except CO, which is in mg/m<sup>3</sup> </th></tr> <tr> <th>IAQI </th> <th>SO<sub>2</sub>, 24 hour </th> <th>SO<sub>2</sub>, 1 hour <sup>（1）</sup> </th> <th>NO<sub>2</sub>, 24 hour </th> <th>NO<sub>2</sub>, 1 hour <sup>（1）</sup> </th> <th>PM<sub>10</sub>, 24 hour </th> <th>CO, 24 hour </th> <th>CO, 1 hour <sup>（1）</sup> </th> <th>O<sub>3</sub>, 1 hour </th> <th>O<sub>3</sub>, 8 hour </th> <th>PM<sub>2.5</sub>, 24 hour </th></tr> <tr> <td>0 </td> <td>0 </td> <td>0 </td> <td>0 </td> <td>0 </td> <td>0 </td> <td>0 </td> <td>0 </td> <td>0 </td> <td>0 </td> <td>0 </td></tr> <tr> <td>50 </td> <td>50 </td> <td>150 </td> <td>40 </td> <td>100 </td> <td>50 </td> <td>2 </td> <td>5 </td> <td>160 </td> <td>100 </td> <td>35 </td></tr> <tr> <td>100 </td> <td>150 </td> <td>500 </td> <td>80 </td> <td>200 </td> <td>150 </td> <td>4 </td> <td>10 </td> <td>200 </td> <td>160 </td> <td>75 </td></tr> <tr> <td>150 </td> <td>475 </td> <td>650 </td> <td>180 </td> <td>700 </td> <td>250 </td> <td>14 </td> <td>35 </td> <td>300 </td> <td>215 </td> <td>115 </td></tr> <tr> <td>200 </td> <td>800 </td> <td>800 </td> <td>280 </td> <td>1200 </td> <td>350 </td> <td>24 </td> <td>60 </td> <td>400 </td> <td>265 </td> <td>150 </td></tr> <tr> <td>300 </td> <td>1600 </td> <td><sup> (2) </sup> </td> <td>565 </td> <td>2340 </td> <td>420 </td> <td>36 </td> <td>90 </td> <td>800 </td> <td>800 </td> <td>250 </td></tr> <tr> <td>400 </td> <td>2100 </td> <td><sup> (2) </sup> </td> <td>750 </td> <td>3090 </td> <td>500 </td> <td>48 </td> <td>120 </td> <td>1000 </td> <td><sup> (3) </sup> </td> <td>350 </td></tr> <tr> <td>500 </td> <td>2620 </td> <td><sup> (2) </sup> </td> <td>940 </td> <td>3840 </td> <td>600 </td> <td>60 </td> <td>150 </td> <td>1200 </td> <td><sup> (3) </sup> </td> <td>500 </td></tr></tbody></table> <p><i>The score for each pollutant is non-linear, as is the final AQI score. Thus an AQI of 300 does not mean twice the pollution of AQI at 150, nor does it mean the air is twice as harmful. The concentration of a pollutant when its IAQI is 100 does not equal twice its concentration when its IAQI is 50, nor does it mean the pollutant is twice as harmful. While an AQI of 50 from day 1 to 182 and AQI of 100 from day 183 to 365 does provide an annual average of 75, it does not mean the pollution is acceptable even if the benchmark of 100 is deemed safe. Because the benchmark is a 24-hour target, and the annual average must match the annual target, it is entirely possible to have safe air every day of the year but still fail the annual pollution benchmark.</i> </p> <table class="wikitable"> <caption>AQI and health implications (HJ 633–2012)<sup id="cite_ref-sepa.gov.cn_20-3" class="reference"><a href="#cite_note-sepa.gov.cn-20"><span class="cite-bracket">[</span>20<span class="cite-bracket">]</span></a></sup> </caption> <tbody><tr> <th style="text-align:center; width:100px;">AQI </th> <th>Air Pollution Level </th> <th style="text-align:center; width:150px;">Air Pollution<br /><br />Category </th> <th>Health Implications </th> <th>Recommended Precautions </th></tr> <tr> <td style="text-align:center;">0-50 </td> <td>Level 1 </td> <td style="text-align:center; background:#00e400;color:#000">Excellent </td> <td>No health implications. </td> <td>Everyone can continue their outdoor activities normally because the air is not polluted. </td></tr> <tr> <td style="text-align:center;">51-100 </td> <td>Level 2 </td> <td style="text-align:center; background:#ffff00;color:#000">Good </td> <td>Some pollutants may slightly affect very few hypersensitive individuals. </td> <td>Only very few hypersensitive people should reduce outdoor activities. </td></tr> <tr> <td style="text-align:center;">101-150 </td> <td>Level 3 </td> <td style="text-align:center; background:#ff7e00;color:#000">Lightly Polluted </td> <td>Healthy people may experience slight irritations and sensitive individuals will be slightly affected to a larger extent because the air is slightly polluted. </td> <td>Children, seniors and individuals suffering respiratory or heart diseases should reduce sustained and high-intensity outdoor exercises. </td></tr> <tr> <td style="text-align:center;">151-200 </td> <td>Level 4 </td> <td style="text-align:center; background:#ff0000;color:#fff">Moderately Polluted </td> <td>Sensitive individuals will experience more serious conditions because the air is moderately polluted. The hearts and respiratory systems of healthy people may be affected. </td> <td>Children, seniors and individuals with respiratory or heart diseases should avoid sustained and high-intensity outdoor exercises. General population should moderately reduce outdoor activities. </td></tr> <tr> <td style="text-align:center;">201-300 </td> <td>Level 5 </td> <td style="text-align:center; background:#99004c;color:#fff">Heavily Polluted </td> <td>Healthy people will commonly show symptoms. People suffering from respiratory or heart diseases will be seriously affected and will experience reduced endurance in activities. </td> <td>Children, seniors and individuals with heart or lung diseases should stay indoors and avoid outdoor activities. General population should reduce outdoor activities. </td></tr> <tr> <td style="text-align:center;">301-500 </td> <td>Level 6 </td> <td style="text-align:center; background:#7e0023;color:#fff">Severely Polluted </td> <td>Healthy people will experience reduced endurance in activities and may also show noticeably strong symptoms. Other illnesses may be triggered in healthy people. Seniors and those suffering from diseases should remain indoors and avoid exercise. Healthy individuals should avoid outdoor activities because the air is severely polluted. </td> <td>Children, seniors and the sick should stay indoors and avoid physical exertion. General population should avoid outdoor activities. </td></tr></tbody></table> <div class="mw-heading mw-heading3"><h3 id="Europe">Europe</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Air_quality_index&action=edit&section=8" title="Edit section: Europe"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The <i>Common Air Quality Index</i> (CAQI)<sup id="cite_ref-aqnow_indices_web_21-0" class="reference"><a href="#cite_note-aqnow_indices_web-21"><span class="cite-bracket">[</span>21<span class="cite-bracket">]</span></a></sup> is an air quality index used in Europe since 2006.<sup id="cite_ref-CAQI_definition_22-0" class="reference"><a href="#cite_note-CAQI_definition-22"><span class="cite-bracket">[</span>22<span class="cite-bracket">]</span></a></sup> In November 2017, the <a href="/wiki/European_Environment_Agency" title="European Environment Agency">European Environment Agency</a> announced the <i>European Air Quality Index</i> (EAQI) and started encouraging its use on websites and for other ways of informing the public about air quality.<sup id="cite_ref-EAQI_announce_23-0" class="reference"><a href="#cite_note-EAQI_announce-23"><span class="cite-bracket">[</span>23<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading4"><h4 id="CAQI">CAQI</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Air_quality_index&action=edit&section=9" title="Edit section: CAQI"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>As of 2012<sup class="plainlinks noexcerpt noprint asof-tag update" style="display:none;"><a class="external text" href="https://en.wikipedia.org/w/index.php?title=Air_quality_index&action=edit">[update]</a></sup>, the <a href="/wiki/European_Union" title="European Union">EU</a>-supported project <i>CiteairII</i> argued that the CAQI had been evaluated on a "large set" of data, and described the CAQI's motivation and definition. <i>CiteairII</i> stated that having an air quality index that would be easy to present to the general public was a major motivation, leaving aside the more complex question of a health-based index, which would require, for example, effects of combined levels of different pollutants. The main aim of the CAQI was to have an index that would encourage wide comparison across the EU, without replacing local indices. <i>CiteairII</i> stated that the "main goal of the CAQI is not to warn people for possible adverse health effects of poor air quality but to attract their attention to urban air pollution and its main source (traffic) and help them decrease their exposure."<sup id="cite_ref-CAQI_definition_22-1" class="reference"><a href="#cite_note-CAQI_definition-22"><span class="cite-bracket">[</span>22<span class="cite-bracket">]</span></a></sup> </p><p>The CAQI is a number on a scale from 0 to 100, where a low value means good air quality and a high value means extremely poor air quality. The index is defined in both hourly and daily versions, and separately near roads (a "roadside" or "traffic" index) or away from roads (a "background" index). As of 2012<sup class="plainlinks noexcerpt noprint asof-tag update" style="display:none;"><a class="external text" href="https://en.wikipedia.org/w/index.php?title=Air_quality_index&action=edit">[update]</a></sup>, the CAQI had two mandatory components for the roadside index, NO<sub>2</sub> and PM<sub>10</sub>, and three mandatory components for the background index, NO<sub>2</sub>, PM<sub>10</sub> and O<sub>3</sub>. It also included optional pollutants PM<sub>2.5</sub>, CO and SO<sub>2</sub>. A "sub-index" is calculated for each of the mandatory (and optional if available) components. The CAQI is defined as the sub-index that represents the worst quality among those components.<sup id="cite_ref-CAQI_definition_22-2" class="reference"><a href="#cite_note-CAQI_definition-22"><span class="cite-bracket">[</span>22<span class="cite-bracket">]</span></a></sup> </p><p>Some of the key pollutant concentrations in μg/m<sup>3</sup> for the hourly background index, the corresponding sub-indices, and five CAQI ranges and verbal descriptions are as follows.<sup id="cite_ref-CAQI_definition_22-3" class="reference"><a href="#cite_note-CAQI_definition-22"><span class="cite-bracket">[</span>22<span class="cite-bracket">]</span></a></sup> </p> <table class="wikitable"> <tbody><tr> <th>Qualitative name </th> <th>Index or sub-index </th> <th colspan="4">Pollutant (hourly) concentration in μg/m<sup>3</sup> </th></tr> <tr> <th colspan="2"> </th> <th>NO<sub>2</sub> μg/m<sup>3</sup> </th> <th>PM<sub>10</sub> </th> <th>O<sub>3</sub> μg/m<sup>3</sup> </th> <th>PM<sub>2.5</sub> (optional) μg/m<sup>3</sup> </th></tr> <tr> <td>Very low </td> <td style="text-align:center; background:#79bc6a;color:#000">0-25 </td> <td>0-50 </td> <td>0-25 </td> <td>0-60 </td> <td>0-15 </td></tr> <tr> <td>Low </td> <td style="text-align:center; background:#bbcf4c;color:#000">25-50 </td> <td>50-100 </td> <td>25-50 </td> <td>60-120 </td> <td>15-30 </td></tr> <tr> <td>Medium </td> <td style="text-align:center; background:#eec20b;color:#000">50-75 </td> <td>100-200 </td> <td>50-90 </td> <td>120-180 </td> <td>30-55 </td></tr> <tr> <td>High </td> <td style="text-align:center; background:#efa003;color:#000">75-100 </td> <td>200-400 </td> <td>90-180 </td> <td>180-240 </td> <td>55-110 </td></tr> <tr> <td>Very high </td> <td style="text-align:center; background:#e8416f;color:#000">>100 </td> <td>>400 </td> <td>>180 </td> <td>>240 </td> <td>>110 </td></tr></tbody></table> <p>Frequently updated CAQI values and maps are shown on www.airqualitynow.eu<sup id="cite_ref-24" class="reference"><a href="#cite_note-24"><span class="cite-bracket">[</span>24<span class="cite-bracket">]</span></a></sup> and other websites.<sup id="cite_ref-aqnow_indices_web_21-1" class="reference"><a href="#cite_note-aqnow_indices_web-21"><span class="cite-bracket">[</span>21<span class="cite-bracket">]</span></a></sup> A separate <i>Year Average Common Air Quality Index</i> (YACAQI) is also defined, in which different pollutant sub-indices are separately normalised to a value typically near unity. For example, the yearly averages of NO<sub>2</sub>, PM<sub>10</sub> and PM<sub>2.5</sub> are divided by 40 μg/m<sup>3</sup>, 40 μg/m<sup>3</sup> and 20 μg/m<sup>3</sup>, respectively. The overall background or traffic YACAQI for a city is the <a href="/wiki/Arithmetic_mean" title="Arithmetic mean">arithmetic mean</a> of a defined subset of these sub-indices.<sup id="cite_ref-CAQI_definition_22-4" class="reference"><a href="#cite_note-CAQI_definition-22"><span class="cite-bracket">[</span>22<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="India">India</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Air_quality_index&action=edit&section=10" title="Edit section: India"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The National Air Quality Index (NAQI) was launched in <a href="/wiki/New_Delhi" title="New Delhi">New Delhi</a> on September 17, 2014, under the <a href="/wiki/Swachh_Bharat_Abhiyan" class="mw-redirect" title="Swachh Bharat Abhiyan">Swachh Bharat Abhiyan</a>.<sup id="cite_ref-25" class="reference"><a href="#cite_note-25"><span class="cite-bracket">[</span>25<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-26" class="reference"><a href="#cite_note-26"><span class="cite-bracket">[</span>26<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-27" class="reference"><a href="#cite_note-27"><span class="cite-bracket">[</span>27<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-28" class="reference"><a href="#cite_note-28"><span class="cite-bracket">[</span>28<span class="cite-bracket">]</span></a></sup> </p><p>The highest AQI in India was recorded in New Delhi on 18th November 2024 with it being 1,081 and the concentration of PM2.5 - particulate matter measuring 2.5 microns or less in diameter that can be carried into lungs, causing deadly diseases and cardiac issues. Expected to soar even higher later or next year. </p><p>The <a href="/wiki/Central_Pollution_Control_Board" title="Central Pollution Control Board">Central Pollution Control Board</a> along with State Pollution Control Boards has been operating National Air Monitoring Program (NAMP) covering 240 cities of the country having more than 342 monitoring stations.<sup id="cite_ref-29" class="reference"><a href="#cite_note-29"><span class="cite-bracket">[</span>29<span class="cite-bracket">]</span></a></sup> An Expert Group comprising medical professionals, air quality experts, academia, advocacy groups, and SPCBs was constituted and a technical study was awarded to <a href="/wiki/IIT_Kanpur" title="IIT Kanpur">IIT Kanpur</a>. IIT Kanpur and the Expert Group recommended an AQI scheme in 2014.<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> While the earlier measuring index was limited to three indicators, the new index measures eight parameters.<sup id="cite_ref-31" class="reference"><a href="#cite_note-31"><span class="cite-bracket">[</span>31<span class="cite-bracket">]</span></a></sup> The continuous monitoring systems that provide data on near real-time basis are installed in New Delhi, <a href="/wiki/Mumbai" title="Mumbai">Mumbai</a>, <a href="/wiki/Pune" title="Pune">Pune</a>, <a href="/wiki/Kolkata" title="Kolkata">Kolkata</a> and <a href="/wiki/Ahmedabad" title="Ahmedabad">Ahmedabad</a>.<sup id="cite_ref-32" class="reference"><a href="#cite_note-32"><span class="cite-bracket">[</span>32<span class="cite-bracket">]</span></a></sup> </p><p>There are six NAQI categories, namely <i>Good</i>, <i>Satisfactory</i>, <i>Moderate</i>, <i>Poor</i>, <i>Very Poor</i> and <i>Severe</i>. The proposed NAQI will consider eight pollutants PM<sub>10</sub>, PM<sub>2.5</sub>, NO<sub>2</sub>, SO<sub>2</sub>, CO, O<sub>3</sub>, NH<sub>3</sub>, and Pb) for which short-term (up to 24-hourly averaging period) National Ambient Air Quality Standards are prescribed.<sup id="cite_ref-33" class="reference"><a href="#cite_note-33"><span class="cite-bracket">[</span>33<span class="cite-bracket">]</span></a></sup> Based on the measured ambient concentrations, corresponding standards and likely health impact, a sub-index is calculated for each of these pollutants. The worst sub-index reflects overall NAQI. Likely health impacts for different NAQI categories and pollutants have also been suggested, with primary inputs from the medical experts in the group. The NAQI values and corresponding ambient concentrations (health breakpoints) as well as associated likely health impacts for the identified eight pollutants are as follows: </p> <table class="wikitable"> <tbody><tr> <th>AQI Category (Range)</th> <th>PM<sub>10</sub><br />24-hr</th> <th>PM<sub>2.5</sub><br />24-hr</th> <th>NO<sub>2</sub><br />24-hr</th> <th>O<sub>3</sub><br />8-hr</th> <th>CO<br />8-hr (mg/m<sup>3</sup>)</th> <th>SO<sub>2</sub><br />24-hr</th> <th>NH<sub>3</sub><br />24-hr</th> <th>Pb<br />24-hr </th></tr> <tr style="background-color:#00b050;color:#000;"> <td>Good (0-50)</td> <td>0-50</td> <td>0-30</td> <td>0-40</td> <td>0-50</td> <td>0–1.0</td> <td>0-40</td> <td>0-200</td> <td>0-0.5 </td></tr> <tr style="background-color:#92d050;color:#000;"> <td>Satisfactory (51–100)</td> <td>51-100</td> <td>31-60</td> <td>41-80</td> <td>51-100</td> <td>1.1-2.0</td> <td>41-80</td> <td>201-400</td> <td>0.6-1.0 </td></tr> <tr style="background-color:#ffff00;color:#000;"> <td>Moderate (101–200)</td> <td>101-250</td> <td>61-90</td> <td>81-180</td> <td>101-168</td> <td>2.1-10</td> <td>81-380</td> <td>401-800</td> <td>1.1-2.0 </td></tr> <tr style="background-color:#ff6500;color:#000;"> <td>Poor (201–300)</td> <td>251-350</td> <td>91-120</td> <td>181-280</td> <td>169-208</td> <td>10.1-17</td> <td>801-1600</td> <td>801-1200</td> <td>2.1-3.0 </td></tr> <tr style="background-color:#ff0000;color:#fff;"> <td>Very Poor (301–400)</td> <td>351-430</td> <td>121-250</td> <td>281-400</td> <td>209–748*</td> <td>17-34</td> <td>801-1600</td> <td>1200-1800</td> <td>3.1-3.5 </td></tr> <tr style="background-color:#c00000;color:#fff;"> <td>Severe (401–500)</td> <td>430+</td> <td>250+</td> <td>400+</td> <td>748+*</td> <td>34+</td> <td>1600+</td> <td>1800+</td> <td>3.5+ </td></tr> </tbody></table> <table class="wikitable"> <tbody><tr> <th>AQI</th> <th>Remark</th> <th>Color Code</th> <th>Possible Health Impacts </th></tr> <tr> <td style="text-align:center;">0-50</td> <td style="text-align:center;">Good</td> <td style="background:#00b050;"></td> <td>Minimal impact </td></tr> <tr> <td style="text-align:center;">51-100</td> <td style="text-align:center;">Satisfactory</td> <td style="background:#92d050;"></td> <td>Minor breathing discomfort to sensitive people </td></tr> <tr> <td style="text-align:center;">101-200</td> <td style="text-align:center;">Moderate</td> <td style="background:#ffff00;"></td> <td>Breathing discomfort to the people with lungs, asthma and heart diseases </td></tr> <tr> <td style="text-align:center;">201-300</td> <td style="text-align:center;">Poor</td> <td style="background:#ff6500;"></td> <td>Breathing discomfort to most people on prolonged exposure </td></tr> <tr> <td style="text-align:center;">301-400</td> <td style="text-align:center;">Very Poor</td> <td style="background:#ff0000;"></td> <td>Respiratory illness on prolonged exposure </td></tr> <tr> <td style="text-align:center;">401-500</td> <td style="text-align:center;">Severe</td> <td style="background:#c00000;"></td> <td>Affects healthy people and seriously impacts those with existing diseases </td></tr> </tbody></table> <div class="mw-heading mw-heading3"><h3 id="Japan">Japan</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Air_quality_index&action=edit&section=11" title="Edit section: Japan"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>According to <a href="/wiki/Japan_Weather_Association" title="Japan Weather Association">Japan Weather Association</a>, Japan uses a different scale to measure the air quality index. </p> <table class="wikitable mw-collapsible"> <tbody><tr> <th style="width:150px;">CAI</th> <th style="width:200px;">Description</th> <th>Health Implications </th></tr> <tr> <td style="text-align:center;">0–50</td> <td style="text-align:center; background:blue;color:white">Good (良い)</td> <td>There is no impact on humans. Outdoor activities are always allowed. </td></tr> <tr> <td style="text-align:center;">51–100</td> <td style="text-align:center; background:green;color:white">Moderate (適度)</td> <td>Outdoor activities are often allowed because air is seldom considered unhealthy. </td></tr> <tr> <td style="text-align:center;">101–200</td> <td style="text-align:center; background:yellow;color:black">Unhealthy (不健康)</td> <td>Outdoor activities are sometimes allowed because air is sometimes considered unhealthy. </td></tr> <tr> <td style="text-align:center;">201–350</td> <td style="text-align:center; background:orange;color:black">Very unhealthy (非常不健康)</td> <td>There are serious health hazards. Outdoor activities are seldom allowed. </td></tr> <tr> <td style="text-align:center;">351–500</td> <td style="text-align:center; background:red;color:white">Hazardous (危険な)</td> <td>Pollutants trigger extremely serious health hazards to humans. Out activities are never allowed. </td></tr></tbody></table> <div class="mw-heading mw-heading3"><h3 id="Mexico">Mexico</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Air_quality_index&action=edit&section=12" title="Edit section: Mexico"><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/%C3%8Dndice_Metropolitano_de_la_Calidad_del_Aire" title="Índice Metropolitano de la Calidad del Aire">Índice Metropolitano de la Calidad del Aire</a></div> <p>The air quality in <a href="/wiki/Mexico_City" title="Mexico City">Mexico City</a> is reported in IMECAs. The IMECA is calculated using the measurements of average times of the chemicals ozone (O<sub>3</sub>), sulfur dioxide (SO<sub>2</sub>), nitrogen dioxide (NO<sub>2</sub>), carbon monoxide (CO), particles smaller than 2.5 micrometers (PM<sub>2.5</sub>), and particles smaller than 10 micrometers (PM<sub>10</sub>).<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. (October 2024)">citation needed</span></a></i>]</sup> </p> <div class="mw-heading mw-heading3"><h3 id="Singapore">Singapore</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Air_quality_index&action=edit&section=13" title="Edit section: Singapore"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p><a href="/wiki/Singapore" title="Singapore">Singapore</a> uses the <a href="/wiki/Pollutant_Standards_Index" title="Pollutant Standards Index">Pollutant Standards Index</a> to report on its air quality,<sup id="cite_ref-34" class="reference"><a href="#cite_note-34"><span class="cite-bracket">[</span>34<span class="cite-bracket">]</span></a></sup> with details of the calculation similar but not identical to those used in Malaysia and Hong Kong.<sup id="cite_ref-35" class="reference"><a href="#cite_note-35"><span class="cite-bracket">[</span>35<span class="cite-bracket">]</span></a></sup> The PSI chart below is grouped by index values and descriptors, according to the <a href="/wiki/National_Environment_Agency" title="National Environment Agency">National Environment Agency</a>.<sup id="cite_ref-36" class="reference"><a href="#cite_note-36"><span class="cite-bracket">[</span>36<span class="cite-bracket">]</span></a></sup> </p> <table class="wikitable"> <tbody><tr> <th>PSI </th> <th>Category </th> <th>Healthy Persons </th> <th>Elderly, Pregnant Women, Children </th> <th>Persons with Chronic Lung Disease or Heart Disease </th></tr> <tr> <td style="text-align:center;">0-50 </td> <td style="text-align:center; background:#479b02;color:#fff">Good </td> <td>Normal activities </td> <td>Normal activities </td> <td>Normal activities </td></tr> <tr> <td style="text-align:center;">51-100 </td> <td style="text-align:center; background:#006fa1;color:#fff">Moderate </td> <td>Normal activities </td> <td>Normal activities </td> <td>Normal activities </td></tr> <tr> <td style="text-align:center;">101-200 </td> <td style="text-align:center; background:#ffce03;color:#000">Unhealthy </td> <td>Reduce prolonged or strenuous outdoor physical exertion </td> <td>Minimise prolonged or strenuous outdoor physical exertion </td> <td>Avoid prolonged or strenuous outdoor physical exertion </td></tr> <tr> <td style="text-align:center;">201-300 </td> <td style="text-align:center; background:#ffa800;color:#000">Very Unhealthy </td> <td>Avoid prolonged or strenuous outdoor physical exertion </td> <td>Minimise outdoor activity </td> <td>Avoid outdoor activity </td></tr> <tr> <td style="text-align:center;">301-500 </td> <td style="text-align:center; background:#d60000;color:#fff">Hazardous </td> <td>Minimise outdoor activity </td> <td>Avoid outdoor activity </td> <td>Avoid outdoor activity </td></tr></tbody></table> <div class="mw-heading mw-heading3"><h3 id="South_Korea">South Korea</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Air_quality_index&action=edit&section=14" title="Edit section: South Korea"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The Ministry of Environment of South Korea uses the Comprehensive Air-quality Index (CAI) to describe the ambient air quality based on the health risks of air pollution. The index aims to help the public easily understand the air quality and protect people's health. The CAI is on a scale from 0 to 500, which is divided into six categories. The higher the CAI value, the greater the level of air pollution. Of values of the five air pollutants, the highest is the CAI value. The index also has associated health effects and a colour representation of the categories as shown below.<sup id="cite_ref-37" class="reference"><a href="#cite_note-37"><span class="cite-bracket">[</span>37<span class="cite-bracket">]</span></a></sup> </p> <table class="wikitable"> <tbody><tr> <th>CAI</th> <th>Description</th> <th>Health Effects </th></tr> <tr> <td style="text-align:center;">0-50</td> <td style="text-align:center; background:#0000ff;color:#fff">Good</td> <td>A level that will not impact patients suffering from diseases related to air pollution </td></tr> <tr> <td style="text-align:center;">51-100</td> <td style="text-align:center; background:#00ff00;color:#000">Moderate</td> <td>A level which may have a meager impact on patients in case of chronic exposure </td></tr> <tr> <td style="text-align:center;">101-250</td> <td style="text-align:center; background:#ffff00;color:#000">Unhealthy</td> <td>A level that may have harmful impacts on patients and members of sensitive groups (children, aged or weak people), and also cause the general public unpleasant feelings </td></tr> <tr> <td style="text-align:center;">251-500</td> <td style="text-align:center; background:#ff0000;color:#fff">Very unhealthy</td> <td>A level which may have a serious impact on patients and members of sensitive groups in case of acute exposure </td></tr> </tbody></table> <p>The <a href="/wiki/N_Seoul_Tower" title="N Seoul Tower">N Seoul Tower</a> on <a href="/wiki/Namsan_(Seoul)" class="mw-redirect" title="Namsan (Seoul)">Namsan Mountain</a> in central <a href="/wiki/Seoul,_South_Korea" class="mw-redirect" title="Seoul, South Korea">Seoul, South Korea</a>, is illuminated in blue, from sunset to 23:00 and 22:00 in winter, on days where the <a href="/wiki/Air_quality#South_Korea" class="mw-redirect" title="Air quality">air quality in Seoul</a> is 45 or less. During the spring of 2012, the Tower was lit up for 52 days, which is four days more than in 2011.<sup id="cite_ref-38" class="reference"><a href="#cite_note-38"><span class="cite-bracket">[</span>38<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="United_Kingdom">United Kingdom</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Air_quality_index&action=edit&section=15" title="Edit section: United Kingdom"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The most commonly used air quality index in the UK is the <i>Daily Air Quality Index</i> recommended by the <a href="/wiki/Committee_on_the_Medical_Effects_of_Air_Pollutants" title="Committee on the Medical Effects of Air Pollutants">Committee on the Medical Effects of Air Pollutants</a> (COMEAP).<sup id="cite_ref-39" class="reference"><a href="#cite_note-39"><span class="cite-bracket">[</span>39<span class="cite-bracket">]</span></a></sup> This index has ten points, which are further grouped into four bands: low, moderate, high and very high. Each of the bands comes with advice for at-risk groups and the general population.<sup id="cite_ref-defra_AQI_40-0" class="reference"><a href="#cite_note-defra_AQI-40"><span class="cite-bracket">[</span>40<span class="cite-bracket">]</span></a></sup> </p> <table class="wikitable"> <tbody><tr> <th>Air Pollution Banding</th> <th>Value</th> <th>Accompanying health messages for at-risk individuals</th> <th>Accompanying health messages for the general population </th></tr> <tr> <td style="text-align:center; background:#9cff9c;color:#000">Low</td> <td style="text-align:center; background:#9cff9c;color:#000">1-3</td> <td><b>Enjoy</b> your usual outdoor activities.</td> <td><b>Enjoy</b> your usual outdoor activities. </td></tr> <tr> <td style="text-align:center; background:#ffff00;color:#000">Moderate</td> <td style="text-align:center; background:#ffff00;color:#000;">4-6</td> <td>Adults and children with lung problems, and adults with heart problems, <b>who experience symptoms</b>, should <b>consider reducing</b> strenuous physical activity, particularly outdoors.</td> <td><b>Enjoy</b> your usual outdoor activities. </td></tr> <tr> <td style="text-align:center; background:#ff6464;color:#000">High</td> <td style="text-align:center; background:#ff6464;color:#000;">7-9</td> <td>Adults and children with lung problems, and adults with heart problems, should <b>reduce</b> strenuous physical exertion, particularly outdoors, and particularly if they experience symptoms. People with asthma may find they need to use their reliever inhalator more often. Older people should also <b>reduce</b> physical exertion.</td> <td>Anyone experiencing discomfort such as sore eyes, cough or sore throat, should <b>consider reducing</b> activity, particularly outdoors. </td></tr> <tr> <td style="text-align:center; background:#ce30ff;color:#000">Very High</td> <td style="text-align:center; background:#ce30ff;color:#000;">10</td> <td>Adults and children with lung problems, adults with heart problems, and older people, should <b>avoid</b> strenuous physical activity. People with asthma may find they need to use their reliever inhaler more often.</td> <td><b>Reduce</b> physical exertion, particularly outdoors, especially if you experience symptoms such as cough or sore throat. </td></tr> </tbody></table> <p>The index is based on the concentrations of five pollutants. The index is calculated from the concentrations of the following pollutants: ozone, nitrogen dioxide, sulfur ioxide, PM2.5 and PM10. The breakpoints between index values are defined for each pollutant separately and the overall index is defined as the maximum value of the index. Different averaging periods are used for different pollutants.<sup id="cite_ref-defra_AQI_40-1" class="reference"><a href="#cite_note-defra_AQI-40"><span class="cite-bracket">[</span>40<span class="cite-bracket">]</span></a></sup> </p> <table class="wikitable"> <tbody><tr> <th>Index</th> <th>Ozone, running 8 hourly mean (μg/m<sup>3</sup>)</th> <th>Nitrogen dioxide, hourly mean (μg/m<sup>3</sup>)</th> <th>Sulfur dioxide, 15 minute mean (μg/m<sup>3</sup>)</th> <th>PM<sub>2.5</sub> particles, 24 hour mean (μg/m<sup>3</sup>)</th> <th>PM<sub>10</sub> particles, 24 hour mean (μg/m<sup>3</sup>) </th></tr> <tr style="background-color:#9cff9c;color:#000;"> <td>1</td> <td>0-33</td> <td>0-67</td> <td>0-88</td> <td>0-11</td> <td>0–16 </td></tr> <tr style="background-color:#31ff00;color:#000;"> <td>2</td> <td>34-66</td> <td>68-134</td> <td>89-177</td> <td>12-23</td> <td>17–33 </td></tr> <tr style="background-color:#31cf00;color:#000;"> <td>3</td> <td>67-100</td> <td>135-200</td> <td>178-266</td> <td>24-35</td> <td>34–50 </td></tr> <tr style="background-color:#ffff00;color:#000;"> <td>4</td> <td>101-120</td> <td>201-267</td> <td>267-354</td> <td>36-41</td> <td>51–58 </td></tr> <tr style="background-color:#ffcf00;color:#000;"> <td>5</td> <td>121-140</td> <td>268-334</td> <td>355-443</td> <td>42-47</td> <td>59–66 </td></tr> <tr style="background-color:#ff9a00;color:#000;"> <td>6</td> <td>141-160</td> <td>335-400</td> <td>444-532</td> <td>48-53</td> <td>67–75 </td></tr> <tr style="background-color:#ff6464;color:#000;"> <td>7</td> <td>161-187</td> <td>401-467</td> <td>533-710</td> <td>54-58</td> <td>76–83 </td></tr> <tr style="background-color:#ff0000;color:#fff;"> <td>8</td> <td>188-213</td> <td>468-534</td> <td>711-887</td> <td>59-64</td> <td>84–91 </td></tr> <tr style="background-color:#990000;color:#fff;"> <td>9</td> <td>214-240</td> <td>535-600</td> <td>888-1064</td> <td>65-70</td> <td>92–100 </td></tr> <tr style="background-color:#ce30ff;color:#000;"> <td>10</td> <td>≥ 241</td> <td>≥ 601</td> <td>≥ 1065</td> <td>≥ 71</td> <td>≥ 101 </td></tr> </tbody></table> <div class="mw-heading mw-heading3"><h3 id="United_States">United States</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Air_quality_index&action=edit&section=16" title="Edit section: United States"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <table class="wikitable"> <tbody><tr> <th>AQI </th> <th>Category </th> <th>Color </th> <th>Health implications </th> <th>What should people do </th></tr> <tr> <td style="text-align:center;">0-50 </td> <td style="text-align:center;">Good </td> <td style="text-align:center; background:#00e400;color:#000">Green </td> <td>Air quality is considered satisfactory, and air pollution poses little or no risk. </td> <td>It's a great day to be active outside. </td></tr> <tr> <td style="text-align:center;">51-100 </td> <td style="text-align:center;">Moderate </td> <td style="text-align:center; background:#ffff00;color:#000">Yellow </td> <td>Air quality is acceptable; however, for some pollutants there may be a moderate health concern for a very small number of people who are unusually sensitive to air pollution. </td> <td>Unusually sensitive people: Consider reducing prolonged or heavy exertion. Watch for symptoms such as coughing or shortness of breath. These are signs to take it easier. <p>Everyone else: It's a good day to be active outside. </p> </td></tr> <tr> <td style="text-align:center;">101-150 </td> <td style="text-align:center;">Unhealthy for Sensitive Groups </td> <td style="text-align:center; background:#ff7e00;color:#000">Orange </td> <td>Members of sensitive groups may experience health effects. The general public is not likely to be affected. </td> <td>Sensitive groups: Reduce prolonged or heavy exertion. It's OK to be active outside, but take more breaks and do less intense activities. Watch for symptoms such as coughing or shortness of breath.<br />People with asthma should follow their asthma action plans and keep quick relief medicine handy.<br />If you have heart disease: Symptoms such as palpitations, shortness of breath, or unusual fatigue may indicate a serious problem. If you have any of these, contact your health care provider. </td></tr> <tr> <td style="text-align:center;">151-200 </td> <td style="text-align:center;">Unhealthy </td> <td style="text-align:center; background:#ff0000;color:#fff">Red </td> <td>Everyone may begin to experience health effects; members of sensitive groups may experience more serious health effects. </td> <td>Sensitive groups: Avoid prolonged or heavy exertion. Move activities indoors or reschedule to a time when the air quality is better. <p>Everyone else: Reduce prolonged or heavy exertion. Take more breaks during all outdoor activities. </p> </td></tr> <tr> <td style="text-align:center;">201-300 </td> <td style="text-align:center;">Very Unhealthy </td> <td style="text-align:center; background:#8f3f97;color:#fff">Purple </td> <td>Health alert: everyone may experience more serious health effects. </td> <td>Sensitive groups: Avoid all physical activity outdoors. Move activities indoors or reschedule to a time when air quality is better. <p>Everyone else: Avoid prolonged or heavy exertion. Consider moving activities indoors or rescheduling to a time when air quality is better. </p> </td></tr> <tr> <td style="text-align:center;">301-500 </td> <td style="text-align:center;">Hazardous </td> <td style="text-align:center; background:#7e0023;color:#fff">Maroon </td> <td>Health warnings of emergency conditions. The entire population is more likely to be affected. </td> <td>Everyone: Avoid all physical activity outdoors. <p>Sensitive groups: Remain indoors and keep activity levels low. Follow tips for keeping particle levels low indoors. </p> </td></tr></tbody></table> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Pm25-24a-super.gif" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/5/54/Pm25-24a-super.gif/220px-Pm25-24a-super.gif" decoding="async" width="220" height="159" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/5/54/Pm25-24a-super.gif/330px-Pm25-24a-super.gif 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/5/54/Pm25-24a-super.gif/440px-Pm25-24a-super.gif 2x" data-file-width="483" data-file-height="350" /></a><figcaption>PM<sub>2.5</sub> 24-Hour AQI Loop, Courtesy US EPA</figcaption></figure> <p>The <a href="/wiki/United_States_Environmental_Protection_Agency" title="United States Environmental Protection Agency">United States Environmental Protection Agency</a> (EPA) has developed an Air Quality Index that is used to report air quality. This AQI is divided into six categories indicating increasing levels of health concern.<sup id="cite_ref-aqi_basic_12-1" class="reference"><a href="#cite_note-aqi_basic-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup> </p><p>The AQI is based on the five "criteria" pollutants regulated under the <a href="/wiki/Clean_Air_Act_(USA)_(1990)" class="mw-redirect" title="Clean Air Act (USA) (1990)">Clean Air Act</a>: ground-level ozone, particulate matter, carbon monoxide, sulfur dioxide, and nitrogen dioxide. The EPA has established <a href="/wiki/National_Ambient_Air_Quality_Standards" title="National Ambient Air Quality Standards">National Ambient Air Quality Standards</a> (NAAQS) for each of these pollutants in order to protect public health. An AQI value of 100 generally corresponds to the level of the NAAQS for the pollutant.<sup id="cite_ref-aqi_basic_12-2" class="reference"><a href="#cite_note-aqi_basic-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup> The <a href="/wiki/Clean_Air_Act_(USA)_(1990)" class="mw-redirect" title="Clean Air Act (USA) (1990)">Clean Air Act (USA) (1990)</a> requires the EPA to review its <a href="/wiki/National_Ambient_Air_Quality_Standards" title="National Ambient Air Quality Standards">National Ambient Air Quality Standards</a> every five years to reflect evolving health effects information. The Air Quality Index is adjusted periodically to reflect these changes. </p> <div class="mw-heading mw-heading4"><h4 id="Computing_the_AQI">Computing the AQI</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Air_quality_index&action=edit&section=17" title="Edit section: Computing the AQI"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The air quality index is a <a href="/wiki/Piecewise_linear_function" title="Piecewise linear function">piecewise linear function</a> of the pollutant concentration. At the boundary between AQI categories, there is a discontinuous jump of one AQI unit. To convert from concentration to AQI this equation is used:<sup id="cite_ref-41" class="reference"><a href="#cite_note-41"><span class="cite-bracket">[</span>41<span class="cite-bracket">]</span></a></sup> </p><p><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 I={\frac {I_{high}-I_{low}}{C_{high}-C_{low}}}(C-C_{low})+I_{low}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>I</mi> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mrow> <msub> <mi>I</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>h</mi> <mi>i</mi> <mi>g</mi> <mi>h</mi> </mrow> </msub> <mo>−</mo> <msub> <mi>I</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>l</mi> <mi>o</mi> <mi>w</mi> </mrow> </msub> </mrow> <mrow> <msub> <mi>C</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>h</mi> <mi>i</mi> <mi>g</mi> <mi>h</mi> </mrow> </msub> <mo>−</mo> <msub> <mi>C</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>l</mi> <mi>o</mi> <mi>w</mi> </mrow> </msub> </mrow> </mfrac> </mrow> <mo stretchy="false">(</mo> <mi>C</mi> <mo>−</mo> <msub> <mi>C</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>l</mi> <mi>o</mi> <mi>w</mi> </mrow> </msub> <mo stretchy="false">)</mo> <mo>+</mo> <msub> <mi>I</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>l</mi> <mi>o</mi> <mi>w</mi> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle I={\frac {I_{high}-I_{low}}{C_{high}-C_{low}}}(C-C_{low})+I_{low}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/29066155a106cd3ddccafdd605f88b805a4ea70f" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.671ex; width:34.784ex; height:6.343ex;" alt="{\displaystyle I={\frac {I_{high}-I_{low}}{C_{high}-C_{low}}}(C-C_{low})+I_{low}}"></span> </p><p>(If multiple pollutants are measured, the calculated AQI is the highest value calculated from the above equation applied for each pollutant.) </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 I}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>I</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle I}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/535ea7fc4134a31cbe2251d9d3511374bc41be9f" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:1.172ex; height:2.176ex;" alt="{\displaystyle I}"></span> = the (Air Quality) index,</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 C}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>C</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle C}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/4fc55753007cd3c18576f7933f6f089196732029" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:1.766ex; height:2.176ex;" alt="{\displaystyle C}"></span> = the pollutant concentration,</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 C_{low}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>C</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>l</mi> <mi>o</mi> <mi>w</mi> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle C_{low}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/90e44bba740a008af76e65f0a6f40d631da2081b" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.671ex; width:4.358ex; height:2.509ex;" alt="{\displaystyle C_{low}}"></span>= the concentration breakpoint that is ≤ <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 C}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>C</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle C}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/4fc55753007cd3c18576f7933f6f089196732029" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:1.766ex; height:2.176ex;" alt="{\displaystyle C}"></span>,</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 C_{high}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>C</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>h</mi> <mi>i</mi> <mi>g</mi> <mi>h</mi> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle C_{high}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/b6defe53ef79559aa23246bf50dcef27d5def487" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:5.144ex; height:2.843ex;" alt="{\displaystyle C_{high}}"></span>= the concentration breakpoint that is ≥ <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 C}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>C</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle C}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/4fc55753007cd3c18576f7933f6f089196732029" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:1.766ex; height:2.176ex;" alt="{\displaystyle C}"></span>,</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 I_{low}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>I</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>l</mi> <mi>o</mi> <mi>w</mi> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle I_{low}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/1e603c14ebdb2489fb8cc77d286055773a817900" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.671ex; width:3.72ex; height:2.509ex;" alt="{\displaystyle I_{low}}"></span>= the index breakpoint corresponding to <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 C_{low}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>C</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>l</mi> <mi>o</mi> <mi>w</mi> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle C_{low}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/90e44bba740a008af76e65f0a6f40d631da2081b" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.671ex; width:4.358ex; height:2.509ex;" alt="{\displaystyle C_{low}}"></span>,</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 I_{high}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>I</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>h</mi> <mi>i</mi> <mi>g</mi> <mi>h</mi> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle I_{high}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/51e25dc5f9c9ba3640ce3b4b33807b8eba64afbe" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:4.506ex; height:2.843ex;" alt="{\displaystyle I_{high}}"></span>= the index breakpoint corresponding to <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 C_{high}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>C</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>h</mi> <mi>i</mi> <mi>g</mi> <mi>h</mi> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle C_{high}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/b6defe53ef79559aa23246bf50dcef27d5def487" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:5.144ex; height:2.843ex;" alt="{\displaystyle C_{high}}"></span>.</dd></dl> <p>The EPA's table of breakpoints is:<sup id="cite_ref-tech_aqi_42-0" class="reference"><a href="#cite_note-tech_aqi-42"><span class="cite-bracket">[</span>42<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-tech_aqi2_43-0" class="reference"><a href="#cite_note-tech_aqi2-43"><span class="cite-bracket">[</span>43<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-44" class="reference"><a href="#cite_note-44"><span class="cite-bracket">[</span>44<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-45" class="reference"><a href="#cite_note-45"><span class="cite-bracket">[</span>45<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-46" class="reference"><a href="#cite_note-46"><span class="cite-bracket">[</span>46<span class="cite-bracket">]</span></a></sup> </p> <table class="wikitable" style="text-align: center;"> <tbody><tr> <th><b><a href="/wiki/Ozone" title="Ozone">O<sub>3</sub></a> (ppb)</b> <p>8-hr </p> </th> <th><b><a href="/wiki/Ozone" title="Ozone">O<sub>3</sub></a> (ppb)</b> <p>1-hr </p> </th> <th><b><a href="/wiki/Particulates" title="Particulates">PM<sub>2.5</sub></a> (μg/m<sup>3</sup>)</b> <p>24-hr </p> </th> <th><b><a href="/wiki/Particulates" title="Particulates">PM<sub>10</sub></a> (μg/m<sup>3</sup>)</b> <p>24-hr </p> </th> <th><b><a href="/wiki/Carbon_monoxide" title="Carbon monoxide">CO</a> (ppm)</b> <p>8-hr </p> </th> <th><b><a href="/wiki/Sulfur_dioxide" title="Sulfur dioxide">SO<sub>2</sub></a> (ppb)</b> <p>1-hr; <span style="color:blue;">24-hr</span> </p> </th> <th><b><a href="/wiki/Nitrogen_dioxide" title="Nitrogen dioxide">NO<sub>2</sub></a> (ppb)</b> <p>1-hr </p> </th> <th><b>AQI</b></th> <th><b>AQI</b> <p><b>Category</b> </p> </th></tr> <tr> <td>0-54</td> <td>-</td> <td>0.0-9.0</td> <td>0-54</td> <td>0.0-4.4</td> <td>0-35</td> <td>0-53</td> <td>0-50</td> <td style="background:#00e400;">Good </td></tr> <tr> <td>55-70</td> <td>-</td> <td>9.1-35.4</td> <td>55-154</td> <td>4.5-9.4</td> <td>36-75</td> <td>54-100</td> <td>51-100</td> <td style="background:#ffff00;">Moderate </td></tr> <tr> <td>71-85</td> <td>125-164</td> <td>35.5-55.4</td> <td>155-254</td> <td>9.5-12.4</td> <td>76-185</td> <td>101-360</td> <td>101-150</td> <td style="background:#ff7e00;">Unhealthy for Sensitive Groups </td></tr> <tr> <td>86-105</td> <td>165-204</td> <td>55.5-125.4</td> <td>255-354</td> <td>12.5-15.4</td> <td>186-304</td> <td>361-649</td> <td>151-200</td> <td style="background:#ff0000;color:#fff">Unhealthy </td></tr> <tr> <td>106-200</td> <td>205-404</td> <td>125.5-225.4</td> <td>355-424</td> <td>15.5-30.4</td> <td>305-604</td> <td>650-1,249</td> <td>201-300</td> <td style="background:#8f3f97;color:#fff">Very Unhealthy </td></tr> <tr> <td>-</td> <td>405-604</td> <td>225.5-325.4</td> <td>425-604</td> <td>30.5-50.4</td> <td>605-1,004</td> <td>1,250-2,049</td> <td>301-500</td> <td style="background:#7e0023;color:#fff">Hazardous </td></tr> </tbody></table> <p>Suppose a monitor records a 24-hour average fine particle (PM<sub>2.5</sub>) concentration of 26.4 micrograms per cubic meter. The equation above results in an AQI of: </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 {\frac {100-51}{35.4-9.1}}(26.4-9.1)+51=83.2}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mrow> <mn>100</mn> <mo>−</mo> <mn>51</mn> </mrow> <mrow> <mn>35.4</mn> <mo>−</mo> <mn>9.1</mn> </mrow> </mfrac> </mrow> <mo stretchy="false">(</mo> <mn>26.4</mn> <mo>−</mo> <mn>9.1</mn> <mo stretchy="false">)</mo> <mo>+</mo> <mn>51</mn> <mo>=</mo> <mn>83.2</mn> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle {\frac {100-51}{35.4-9.1}}(26.4-9.1)+51=83.2}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/306b0182f8d5073053322f7e6256ceaa3b323750" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.005ex; width:34.936ex; height:5.343ex;" alt="{\displaystyle {\frac {100-51}{35.4-9.1}}(26.4-9.1)+51=83.2}"></span></dd></dl> <p>which rounds to index value of 83, corresponding to air quality in the "Moderate" range.<sup id="cite_ref-47" class="reference"><a href="#cite_note-47"><span class="cite-bracket">[</span>47<span class="cite-bracket">]</span></a></sup> To convert an air pollutant concentration to an AQI, EPA has developed a calculator.<sup id="cite_ref-48" class="reference"><a href="#cite_note-48"><span class="cite-bracket">[</span>48<span class="cite-bracket">]</span></a></sup> </p><p>If multiple pollutants are measured at a monitoring site, then the largest or "dominant" AQI value is reported for the location. The ozone AQI between 100 and 300 is computed by selecting the larger of the AQI calculated with a 1-hour ozone value and the AQI computed with the 8-hour ozone value. </p><p>Eight-hour ozone averages do not define AQI values greater than 300; AQI values of 301 or greater are calculated with 1-hour ozone concentrations. 1-hour SO<sub>2</sub> values do not define higher AQI values greater than 200. AQI values of 201 or greater are calculated with 24-hour SO<sub>2</sub> concentrations. </p><p>Real-time monitoring data from continuous monitors are typically available as 1-hour averages. However, computation of the AQI for some pollutants requires averaging over multiple hours of data. (For example, calculation of the ozone AQI requires computation of an 8-hour average and computation of the PM<sub>2.5</sub> or PM<sub>10</sub> AQI requires a 24-hour average.) To accurately reflect the current air quality, the multi-hour average used for the AQI computation should be centered on the current time, but as concentrations of future hours are unknown and are difficult to estimate accurately, EPA uses surrogate concentrations to estimate these multi-hour averages. For reporting the PM<sub>2.5</sub>, PM<sub>10</sub> and ozone air quality indices, this surrogate concentration is called the <a href="/wiki/Nowcast_(Air_Quality_Index)" class="mw-redirect" title="Nowcast (Air Quality Index)">NowCast</a>. The Nowcast is a particular type of weighted average that provides more weight to the most recent air quality data when air pollution levels are changing.<sup id="cite_ref-49" class="reference"><a href="#cite_note-49"><span class="cite-bracket">[</span>49<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-50" class="reference"><a href="#cite_note-50"><span class="cite-bracket">[</span>50<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading4"><h4 id="Public_availability_of_the_AQI">Public availability of the AQI</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Air_quality_index&action=edit&section=18" title="Edit section: Public availability of the AQI"><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:Global_air_pollution_map.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/7/7b/Global_air_pollution_map.png/220px-Global_air_pollution_map.png" decoding="async" width="220" height="112" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/7/7b/Global_air_pollution_map.png/330px-Global_air_pollution_map.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/7/7b/Global_air_pollution_map.png/440px-Global_air_pollution_map.png 2x" data-file-width="2753" data-file-height="1400" /></a><figcaption>A global air quality map</figcaption></figure> <p>Real time monitoring data and forecasts of air quality that are color-coded in terms of the air quality index are available from EPA's AirNow web site.<sup id="cite_ref-51" class="reference"><a href="#cite_note-51"><span class="cite-bracket">[</span>51<span class="cite-bracket">]</span></a></sup> Other organizations provide monitoring for members of sensitive groups such as asthmatics, children and adults over the age of 65.<sup id="cite_ref-52" class="reference"><a href="#cite_note-52"><span class="cite-bracket">[</span>52<span class="cite-bracket">]</span></a></sup> Historical air monitoring data including AQI charts and maps are available at EPA's AirData website.<sup id="cite_ref-53" class="reference"><a href="#cite_note-53"><span class="cite-bracket">[</span>53<span class="cite-bracket">]</span></a></sup> There is a free email subscription service for New York inhabitants – AirNYC.<sup id="cite_ref-54" class="reference"><a href="#cite_note-54"><span class="cite-bracket">[</span>54<span class="cite-bracket">]</span></a></sup> Subscribers get notifications about the changes in the AQI values for the selected location (e.g. home address), based on air quality conditions. A detailed map containing current AQI levels and a two-day AQI forecast is available at the Aerostate web site.<sup id="cite_ref-55" class="reference"><a href="#cite_note-55"><span class="cite-bracket">[</span>55<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading4"><h4 id="Regulatory_Air_Monitors_and_Low_Cost_Sensors">Regulatory Air Monitors and Low Cost Sensors</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Air_quality_index&action=edit&section=19" title="Edit section: Regulatory Air Monitors and Low Cost Sensors"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Historically, EPA has only allowed data from regulatory monitors operated by regulatory or public health professionals to be included in its real time national maps.<sup id="cite_ref-56" class="reference"><a href="#cite_note-56"><span class="cite-bracket">[</span>56<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-57" class="reference"><a href="#cite_note-57"><span class="cite-bracket">[</span>57<span class="cite-bracket">]</span></a></sup> In the past decade, low cost sensors (LCS's) have become increasingly popular with citizen scientists, and large LCS networks have sprung up in the US and across the globe. Recently, EPA has developed a data correction algorithm<sup id="cite_ref-58" class="reference"><a href="#cite_note-58"><span class="cite-bracket">[</span>58<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-59" class="reference"><a href="#cite_note-59"><span class="cite-bracket">[</span>59<span class="cite-bracket">]</span></a></sup> for a particular brand of PM<sub>2.5</sub> LCS (the <a rel="nofollow" class="external text" href="https://www2.purpleair.com/products/list">Purple Air</a> monitor) that makes the LCS data comparable to regulatory data for the purpose of computing the AQI. This corrected LCS data currently appears alongside regulatory data on EPA's national fire map.<sup id="cite_ref-60" class="reference"><a href="#cite_note-60"><span class="cite-bracket">[</span>60<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading4"><h4 id="History_of_the_AQI">History of the AQI</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Air_quality_index&action=edit&section=20" title="Edit section: History of the AQI"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The AQI made its debut in 1968, when the National Air Pollution Control Administration undertook an initiative to develop an air quality index and to apply the methodology to <a href="/wiki/Metropolitan_Statistical_Areas" class="mw-redirect" title="Metropolitan Statistical Areas">Metropolitan Statistical Areas</a>. The impetus was to draw public attention to the issue of air pollution and indirectly push responsible local public officials to take action to control sources of pollution and enhance air quality within their jurisdictions. </p><p>Jack Fensterstock, the head of the National Inventory of Air Pollution Emissions and Control Branch, was tasked to lead the development of the methodology and to compile the air quality and emissions data necessary to test and calibrate resultant indices.<sup id="cite_ref-61" class="reference"><a href="#cite_note-61"><span class="cite-bracket">[</span>61<span class="cite-bracket">]</span></a></sup> </p><p>The initial iteration of the air quality index used standardized ambient pollutant concentrations to yield individual pollutant indices. These indices were then weighted and summed to form a single total air quality index. The overall methodology could use concentrations that are taken from ambient monitoring data or are predicted by means of a diffusion model. The concentrations were then converted into a standard statistical distribution with a preset mean and standard deviation. The resultant individual pollutant indices are assumed to be equally weighted, although values other than unity can be used. Likewise, the index can incorporate any number of pollutants although it was only used to combine <a href="/wiki/Sulfur_Oxides" class="mw-redirect" title="Sulfur Oxides">SO<sub>x</sub></a>, <a href="/wiki/Carbon_Monoxide" class="mw-redirect" title="Carbon Monoxide">CO</a>, and TSP<sup id="cite_ref-TSP_Computation_62-0" class="reference"><a href="#cite_note-TSP_Computation-62"><span class="cite-bracket">[</span>62<span class="cite-bracket">]</span></a></sup> because of a lack of available data for other pollutants. </p><p>While the methodology was designed to be robust, the practical application for all metropolitan areas proved to be inconsistent due to the paucity of ambient air quality monitoring data, lack of agreement on weighting factors, and non-uniformity of air quality standards across geographical and political boundaries. Despite these issues, the publication of lists ranking metropolitan areas achieved the public policy objectives and led to the future development of improved indices and their routine application. </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=Air_quality_index&action=edit&section=21" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239009302">.mw-parser-output .portalbox{padding:0;margin:0.5em 0;display:table;box-sizing:border-box;max-width:175px;list-style:none}.mw-parser-output .portalborder{border:1px solid var(--border-color-base,#a2a9b1);padding:0.1em;background:var(--background-color-neutral-subtle,#f8f9fa)}.mw-parser-output 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(January 2022). <a rel="nofollow" class="external text" href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9784900">"Correction and Accuracy of PurpleAir PM2.5 Measurements for Extreme Wildfire Smoke"</a>. <i>Sensors</i>. <b>22</b> (24): 9669. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2022Senso..22.9669B">2022Senso..22.9669B</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.3390%2Fs22249669">10.3390/s22249669</a></span>. <a href="/wiki/ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/1424-8220">1424-8220</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/PMC9784900">9784900</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/36560038">36560038</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Sensors&rft.atitle=Correction+and+Accuracy+of+PurpleAir+PM2.5+Measurements+for+Extreme+Wildfire+Smoke&rft.volume=22&rft.issue=24&rft.pages=9669&rft.date=2022-01&rft_id=https%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fpmc%2Farticles%2FPMC9784900%23id-name%3DPMC&rft_id=info%3Abibcode%2F2022Senso..22.9669B&rft_id=info%3Apmid%2F36560038&rft_id=info%3Adoi%2F10.3390%2Fs22249669&rft.issn=1424-8220&rft.aulast=Barkjohn&rft.aufirst=Karoline+K.&rft.au=Holder%2C+Amara+L.&rft.au=Frederick%2C+Samuel+G.&rft.au=Clements%2C+Andrea+L.&rft_id=https%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fpmc%2Farticles%2FPMC9784900&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAir+quality+index" class="Z3988"></span></span> </li> <li id="cite_note-60"><span class="mw-cite-backlink"><b><a href="#cite_ref-60">^</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://fire.airnow.gov/#">"Fire and Smoke Map"</a>. <i>fire.airnow.gov</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2023-08-04</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=fire.airnow.gov&rft.atitle=Fire+and+Smoke+Map&rft_id=https%3A%2F%2Ffire.airnow.gov%2F%23&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAir+quality+index" class="Z3988"></span></span> </li> <li id="cite_note-61"><span class="mw-cite-backlink"><b><a href="#cite_ref-61">^</a></b></span> <span class="reference-text">J.C Fensterstock et al., " The Development and Utilization of an Air Quality Index," Paper No. 69–73, presented at the 62nd Annual Meeting of the Air Pollution Control Administration, June 1969.</span> </li> <li id="cite_note-TSP_Computation-62"><span class="mw-cite-backlink"><b><a href="#cite_ref-TSP_Computation_62-0">^</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.ecfr.gov/current/title-40/chapter-I/subchapter-C/part-50/appendix-Appendix%20B%20to%20Part%2050#o">"Appendix B to Part 50—Reference Method for the Determination of Suspended Particulate Matter in the Atmosphere (High-Volume Method)"</a>. US EPA. 2023-06-29<span class="reference-accessdate">. Retrieved <span class="nowrap">2023-07-01</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Appendix+B+to+Part+50%E2%80%94Reference+Method+for+the+Determination+of+Suspended+Particulate+Matter+in+the+Atmosphere+%28High-Volume+Method%29&rft.pub=US+EPA&rft.date=2023-06-29&rft_id=https%3A%2F%2Fwww.ecfr.gov%2Fcurrent%2Ftitle-40%2Fchapter-I%2Fsubchapter-C%2Fpart-50%2Fappendix-Appendix%2520B%2520to%2520Part%252050%23o&rfr_id=info%3Asid%2Fen.wikipedia.org%3AAir+quality+index" class="Z3988"></span></span> </li> </ol></div> <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=Air_quality_index&action=edit&section=23" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Some of the following websites display actively updated air quality index maps; others are archived versions of inactive websites: </p> <ul><li>Global: <ul><li><a rel="nofollow" class="external text" href="http://aqicn.org/map/world/#@g/2.0574/7.9102/2z">Worldwide Air Pollution: Real-time Air Quality Index Visual Map</a></li></ul></li> <li>Europe: <ul><li><a rel="nofollow" class="external text" href="http://www.airqualitynow.eu/index.php">CAQI</a>- AirqualityNow</li> <li><a rel="nofollow" class="external text" href="http://www.eea.europa.eu/themes/air/air-quality-index">EAQI</a> - <a href="/wiki/European_Environment_Agency" title="European Environment Agency">European Environment Agency</a></li> <li><a rel="nofollow" class="external text" href="http://www.airquality.co.uk/archive/index.php">The UK Air Quality Archive</a></li></ul></li> <li>North America: <ul><li><a rel="nofollow" class="external text" href="https://www.airnow.gov/">AQI at airnow.gov</a> - cross-agency U.S. Government site</li> <li><a rel="nofollow" class="external text" href="https://web.archive.org/web/20070623011137/http://air.state.nm.us/">New Mexico Air Quality and API data</a> - Example of how New Mexico Environment Department publishes their Air Quality and API data.</li> <li class="mw-empty-elt"></li> <li><a rel="nofollow" class="external text" href="https://www.cays.com/wp-content/uploads/2024/04/air-quality-index.pdf">EPA Air Quality Index</a> - A Guide to Air Quality and Your Health</li> <li><a rel="nofollow" class="external text" href="https://web.archive.org/web/20060706053637/http://www.msc-smc.ec.gc.ca/aq_smog/index_e.cfm">AQI at Meteorological Service of Canada</a></li> <li><a rel="nofollow" class="external text" href="https://web.archive.org/web/20070613193732/http://www.sparetheair.org/data/air_quality.htm">San Francisco Bay Area Spare-the-Air</a> - AQI explanation</li></ul></li> <li>Asia: <ul><li><a rel="nofollow" class="external text" href="https://web.archive.org/web/20070719042151/http://eng.airkorea.or.kr/cai/main.jsp">CAI at Airkorea.or.kr</a> - website of South Korea Environmental Management Corp.</li> <li><a rel="nofollow" class="external text" href="https://apims.doe.gov.my/home.html">Malaysia Air Pollution Index</a></li> <li><a rel="nofollow" class="external text" href="https://web.archive.org/web/20070410055414/http://www.epd-asg.gov.hk/">API at Hong Kong</a> - Environmental Protection Department of the Government of the Hong Kong Special Administrative Region <i>(inactive as of 19 February 2018<sup class="plainlinks noexcerpt noprint asof-tag update" style="display:none;"><a class="external text" href="https://en.wikipedia.org/w/index.php?title=Air_quality_index&action=edit">[update]</a></sup>)</i></li> <li><a rel="nofollow" class="external text" href="http://aqmthai.com/index.php?lang=en">AQI in Thailand</a> <a rel="nofollow" class="external text" href="https://web.archive.org/web/20170606174552/http://aqmthai.com/index.php?lang=en">Archived</a> 2017-06-06 at the <a href="/wiki/Wayback_Machine" title="Wayback Machine">Wayback Machine</a></li> <li><a rel="nofollow" class="external text" href="http://enviinfo.cem.gov.vn/">AQI in Vietnam</a> <ul><li><a rel="nofollow" class="external text" href="https://moitruongthudo.vn/">AQI in Hanoi</a></li> <li><a rel="nofollow" class="external text" href="http://www.aqivn.org/en/">Unofficial PM25 AQI in Hanoi, Vietnam</a> <a rel="nofollow" class="external text" href="https://web.archive.org/web/20170617074153/http://www.aqivn.org/en/">Archived</a> 2017-06-17 at the <a href="/wiki/Wayback_Machine" title="Wayback Machine">Wayback Machine</a></li></ul></li></ul></li></ul> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><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="Pollution" style="padding:3px"><table class="nowraplinks mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2" style="background:#fadcc5"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239400231"><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Pollution" title="Template:Pollution"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Pollution" title="Template talk:Pollution"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Pollution" title="Special:EditPage/Template:Pollution"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Pollution" style="font-size:114%;margin:0 4em"><a href="/wiki/Pollution" title="Pollution">Pollution</a></div></th></tr><tr><td class="navbox-abovebelow" colspan="2" style="background:#fadcc5"><div><a href="/wiki/History_of_environmental_pollution" title="History of environmental pollution">History</a></div></td></tr><tr><th scope="row" class="navbox-group" style="background:#fadcc5;width:1%;line-height:1.3em;"><a href="/wiki/Air_pollution" title="Air pollution">Air</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Acid_rain" title="Acid rain">Acid rain</a></li> <li><a class="mw-selflink selflink">Air quality index</a></li> <li><a href="/wiki/Atmospheric_dispersion_modeling" title="Atmospheric dispersion modeling">Atmospheric dispersion modeling</a></li> <li><a href="/wiki/Chlorofluorocarbon" title="Chlorofluorocarbon">Chlorofluorocarbon</a></li> <li><a href="/wiki/Combustion" title="Combustion">Combustion</a> <ul><li><a href="/wiki/Biofuel" title="Biofuel">Biofuel</a></li> <li><a href="/wiki/Biomass" title="Biomass">Biomass</a></li> <li><a href="/wiki/Joss_paper" title="Joss paper">Joss paper</a></li> <li><a href="/wiki/Open_burning_of_waste" title="Open burning of waste">Open burning of waste</a></li></ul></li> <li><a href="/wiki/Construction" title="Construction">Construction</a> <ul><li><a href="/wiki/Renovation" title="Renovation">Renovation</a></li></ul></li> <li><a href="/wiki/Demolition" title="Demolition">Demolition</a></li> <li><a href="/wiki/Exhaust_gas" title="Exhaust gas">Exhaust gas</a> <ul><li><a href="/wiki/Diesel_exhaust" title="Diesel exhaust">Diesel exhaust</a></li></ul></li> <li><a href="/wiki/Haze" title="Haze">Haze</a> <ul><li><a href="/wiki/Smoke" title="Smoke">Smoke</a></li></ul></li> <li><a href="/wiki/Indoor_air_quality" title="Indoor air quality">Indoor air quality</a></li> <li><a href="/wiki/Internal_combustion_engine" title="Internal combustion engine">Internal combustion engine</a></li> <li><a href="/wiki/Global_dimming" title="Global dimming">Global dimming</a></li> <li><a href="/wiki/Global_distillation" title="Global distillation">Global distillation</a></li> <li><a href="/wiki/Mining" title="Mining">Mining</a></li> <li><a href="/wiki/Ozone_depletion" title="Ozone depletion">Ozone depletion</a></li> <li><a href="/wiki/Particulates" title="Particulates">Particulates</a> <ul><li><a href="/wiki/Asbestos" title="Asbestos">Asbestos</a></li> <li><a href="/wiki/Metal_working" class="mw-redirect" title="Metal working">Metal working</a></li> <li><a href="/wiki/Oil_refining" class="mw-redirect" title="Oil refining">Oil refining</a></li> <li><a href="/wiki/Wood_dust" class="mw-redirect" title="Wood dust">Wood dust</a></li> <li><a href="/wiki/Welding" title="Welding">Welding</a></li></ul></li> <li><a href="/wiki/Persistent_organic_pollutant" title="Persistent organic pollutant">Persistent organic pollutant</a></li> <li><a href="/wiki/Smelting" title="Smelting">Smelting</a></li> <li><a href="/wiki/Smog" title="Smog">Smog</a></li> <li><a href="/wiki/Soot" title="Soot">Soot</a> <ul><li><a href="/wiki/Black_carbon" title="Black carbon">Black carbon</a></li></ul></li> <li><a href="/wiki/Volatile_organic_compound" title="Volatile organic compound">Volatile organic compound</a></li> <li><a href="/wiki/Waste" title="Waste">Waste</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="background:#fadcc5;width:1%;line-height:1.3em;"><a href="/wiki/Biological_pollution" title="Biological pollution">Biological</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Biological_hazard" title="Biological hazard">Biological hazard</a></li> <li><a href="/wiki/Genetic_pollution" title="Genetic pollution">Genetic pollution</a></li> <li><a href="/wiki/Introduced_species" title="Introduced species">Introduced species</a> <ul><li><a href="/wiki/Invasive_species" title="Invasive species">Invasive species</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="background:#fadcc5;width:1%;line-height:1.3em;">Digital</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Information_pollution" title="Information pollution">Information pollution</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="background:#fadcc5;width:1%;line-height:1.3em;"><a href="/wiki/Electromagnetic_radiation_and_health" title="Electromagnetic radiation and health">Electromagnetic</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Light_pollution" title="Light pollution">Light</a> <ul><li><a href="/wiki/Ecological_light_pollution" title="Ecological light pollution">Ecological light pollution</a></li> <li><a href="/wiki/Overillumination" class="mw-redirect" title="Overillumination">Overillumination</a></li></ul></li> <li><a href="/wiki/Radio_spectrum_pollution" title="Radio spectrum pollution">Radio spectrum pollution</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="background:#fadcc5;width:1%;line-height:1.3em;">Natural</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Ozone" title="Ozone">Ozone</a></li> <li><a href="/wiki/Radium_and_radon_in_the_environment" title="Radium and radon in the environment">Radium and radon in the environment</a></li> <li><a href="/wiki/Volcanic_ash" title="Volcanic ash">Volcanic ash</a></li> <li><a href="/wiki/Wildfire" title="Wildfire">Wildfire</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="background:#fadcc5;width:1%;line-height:1.3em;"><a href="/wiki/Noise_pollution" title="Noise pollution">Noise</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Environmental_effects_of_transport" class="mw-redirect" title="Environmental effects of transport">Transportation</a> <ul><li>Land</li> <li><a href="/wiki/Environmental_effects_of_shipping" class="mw-redirect" title="Environmental effects of shipping">Water</a></li> <li><a href="/wiki/Environmental_effects_of_aviation" class="mw-redirect" title="Environmental effects of aviation">Air</a></li> <li><a href="/wiki/Rail_transport" title="Rail transport">Rail</a></li> <li><a href="/wiki/Sustainable_transport" title="Sustainable transport">Sustainable transport</a></li></ul></li> <li><a href="/wiki/Urbanization" title="Urbanization">Urban</a></li> <li><a href="/wiki/Sonar" title="Sonar">Sonar</a> <ul><li><a href="/wiki/Marine_mammals_and_sonar" title="Marine mammals and sonar">Marine mammals and sonar</a></li></ul></li> <li>Industrial</li> <li>Military</li> <li>Abstract</li> <li><a href="/wiki/Noise_control" title="Noise control">Noise control</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="background:#fadcc5;width:1%;line-height:1.3em;"><a href="/wiki/Radioactive_contamination" title="Radioactive contamination">Radiation</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Actinides_in_the_environment" title="Actinides in the environment">Actinides</a></li> <li><a href="/wiki/Bioremediation_of_radioactive_waste" title="Bioremediation of radioactive waste">Bioremediation</a></li> <li><a href="/wiki/Nuclear_fission_product" title="Nuclear fission product">Nuclear fission</a></li> <li><a href="/wiki/Nuclear_fallout" title="Nuclear fallout">Nuclear fallout</a></li> <li><a href="/wiki/Plutonium_in_the_environment" title="Plutonium in the environment">Plutonium</a></li> <li><a href="/wiki/Acute_radiation_syndrome" title="Acute radiation syndrome">Poisoning</a></li> <li><a href="/wiki/Environmental_radioactivity" title="Environmental radioactivity">Radioactivity</a></li> <li><a href="/wiki/Uranium_in_the_environment" title="Uranium in the environment">Uranium</a></li> <li><a href="/wiki/Electromagnetic_radiation_and_health" title="Electromagnetic radiation and health">Electromagnetic radiation and health</a></li> <li><a href="/wiki/Radioactive_waste" title="Radioactive waste">Radioactive waste</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="background:#fadcc5;width:1%;line-height:1.3em;"><a href="/wiki/Soil_contamination" title="Soil contamination">Soil</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Agricultural_pollution" title="Agricultural pollution">Agricultural pollution</a> <ul><li><a href="/wiki/Herbicide" title="Herbicide">Herbicides</a></li> <li><a href="/wiki/Manure_management" title="Manure management">Manure waste</a></li> <li><a href="/wiki/Pesticide" title="Pesticide">Pesticides</a></li></ul></li> <li><a href="/wiki/Land_degradation" title="Land degradation">Land degradation</a></li> <li><a href="/wiki/Bioremediation" title="Bioremediation">Bioremediation</a></li> <li><a href="/wiki/Open_defecation" title="Open defecation">Open defecation</a></li> <li><a href="/wiki/Electrical_resistance_heating" title="Electrical resistance heating">Electrical resistance heating</a></li> <li><a href="/wiki/Soil_guideline_value" title="Soil guideline value">Soil guideline values</a></li> <li><a href="/wiki/Phytoremediation" title="Phytoremediation">Phytoremediation</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="background:#fadcc5;width:1%;line-height:1.3em;">Solid waste</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Advertising_mail" title="Advertising mail">Advertising mail</a></li> <li><a href="/wiki/Biodegradable_waste" title="Biodegradable waste">Biodegradable waste</a></li> <li><a href="/wiki/Brown_waste" title="Brown waste">Brown waste</a></li> <li><a href="/wiki/Electronic_waste" title="Electronic waste">Electronic waste</a> <ul><li><a href="/wiki/Battery_recycling" title="Battery recycling">Battery recycling</a></li></ul></li> <li><a href="/wiki/Foam_food_container" title="Foam food container">Foam food container</a></li> <li><a href="/wiki/Food_loss_and_waste" title="Food loss and waste">Food waste</a></li> <li><a href="/wiki/Green_waste" title="Green waste">Green waste</a></li> <li><a href="/wiki/Hazardous_waste" title="Hazardous waste">Hazardous waste</a> <ul><li><a href="/wiki/Biomedical_waste" title="Biomedical waste">Biomedical waste</a></li> <li><a href="/wiki/Chemical_waste" title="Chemical waste">Chemical waste</a></li> <li><a href="/wiki/Construction_waste" title="Construction waste">Construction waste</a></li> <li><a href="/wiki/Lead_poisoning" title="Lead poisoning">Lead poisoning</a></li> <li><a href="/wiki/Mercury_poisoning" title="Mercury poisoning">Mercury poisoning</a></li> <li><a href="/wiki/Toxic_waste" title="Toxic waste">Toxic waste</a></li></ul></li> <li><a href="/wiki/Industrial_waste" title="Industrial waste">Industrial waste</a> <ul><li><a href="/wiki/Lead_smelting" title="Lead smelting">Lead smelting</a></li></ul></li> <li><a href="/wiki/Litter" title="Litter">Litter</a></li> <li><a href="/wiki/Environmental_effects_of_mining" class="mw-redirect" title="Environmental effects of mining">Mining</a> <ul><li><a href="/wiki/Coal_mining" title="Coal mining">Coal mining</a></li> <li><a href="/wiki/Gold_mining" title="Gold mining">Gold mining</a></li> <li><a href="/wiki/Surface_mining" title="Surface mining">Surface mining</a></li> <li><a href="/wiki/Deep_sea_mining" title="Deep sea mining">Deep sea mining</a></li> <li><a href="/wiki/Tailings" title="Tailings">Mining waste</a></li> <li><a href="/wiki/Uranium_mining" title="Uranium mining">Uranium mining</a></li></ul></li> <li><a href="/wiki/Municipal_solid_waste" title="Municipal solid waste">Municipal solid waste</a> <ul><li><a href="/wiki/Garbage" title="Garbage">Garbage</a></li></ul></li> <li><a href="/wiki/Pollution_from_nanomaterials" title="Pollution from nanomaterials">Nanomaterials</a></li> <li><a href="/wiki/Plastic_pollution" title="Plastic pollution">Plastic pollution</a> <ul><li><a href="/wiki/Microplastics" title="Microplastics">Microplastics</a></li></ul></li> <li><a href="/wiki/Packaging_waste" title="Packaging waste">Packaging waste</a></li> <li><a href="/wiki/Post-consumer_waste" title="Post-consumer waste">Post-consumer waste</a></li> <li><a href="/wiki/Waste_management" title="Waste management">Waste management</a> <ul><li><a href="/wiki/Landfill" title="Landfill">Landfill</a></li> <li><a href="/wiki/Thermal_treatment" title="Thermal treatment">Thermal treatment</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="background:#fadcc5;width:1%;line-height:1.3em;"><a href="/wiki/Space_debris" title="Space debris"> Space</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Satellite" title="Satellite">Satellite</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="background:#fadcc5;width:1%;line-height:1.3em;"><a href="/wiki/Visual_pollution" title="Visual pollution">Visual</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Air_travel" title="Air travel">Air travel</a></li> <li><a href="/wiki/Clutter_(advertising)" title="Clutter (advertising)">Clutter (advertising)</a></li> <li><a href="/wiki/Traffic_sign" title="Traffic sign">Traffic signs</a></li> <li><a href="/wiki/Overhead_power_line" title="Overhead power line">Overhead power lines</a></li> <li><a href="/wiki/Vandalism" title="Vandalism">Vandalism</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="background:#fadcc5;width:1%;line-height:1.3em;"><a href="/wiki/Environmental_impact_of_war" title="Environmental impact of war">War</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Chemical_warfare" title="Chemical warfare">Chemical warfare</a></li> <li><a href="/wiki/Herbicidal_warfare" title="Herbicidal warfare">Herbicidal warfare</a> (<a href="/wiki/Agent_Orange" title="Agent Orange">Agent Orange</a>)</li> <li><a href="/wiki/Nuclear_holocaust" title="Nuclear holocaust">Nuclear holocaust</a> (<a href="/wiki/Nuclear_fallout" title="Nuclear fallout">Nuclear fallout</a> - <a href="/wiki/Nuclear_famine" title="Nuclear famine">nuclear famine</a> - <a href="/wiki/Nuclear_winter" title="Nuclear winter">nuclear winter</a>)</li> <li><a href="/wiki/Scorched_earth" title="Scorched earth">Scorched earth</a></li> <li><a href="/wiki/Unexploded_ordnance" title="Unexploded ordnance">Unexploded ordnance</a></li> <li><a href="/wiki/War_and_environmental_law" title="War and environmental law">War and environmental law</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="background:#fadcc5;width:1%;line-height:1.3em;"><a href="/wiki/Water_pollution" title="Water pollution">Water</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Agricultural_wastewater_treatment" title="Agricultural wastewater treatment">Agricultural wastewater</a></li> <li><a href="/wiki/Biological_pollution" title="Biological pollution">Biological pollution</a></li> <li><a href="/wiki/Waterborne_diseases" class="mw-redirect" title="Waterborne diseases">Diseases</a></li> <li><a href="/wiki/Eutrophication" title="Eutrophication">Eutrophication</a></li> <li><a href="/wiki/Firewater_(fire_fighting)" title="Firewater (fire fighting)">Firewater</a></li> <li><a href="/wiki/Freshwater_environmental_quality_parameters" title="Freshwater environmental quality parameters">Freshwater</a></li> <li><a href="/wiki/Groundwater_pollution" title="Groundwater pollution">Groundwater</a></li> <li><a href="/wiki/Hypoxia_(environmental)" title="Hypoxia (environmental)">Hypoxia</a></li> <li><a href="/wiki/Industrial_wastewater_treatment" title="Industrial wastewater treatment">Industrial wastewater</a></li> <li><a href="/wiki/Marine_pollution" title="Marine pollution">Marine</a> <ul><li><a href="/wiki/Marine_debris" title="Marine debris">debris</a></li></ul></li> <li><a href="/wiki/Environmental_monitoring" title="Environmental monitoring">Monitoring</a></li> <li><a href="/wiki/Nonpoint_source_pollution" title="Nonpoint source pollution">Nonpoint source pollution</a></li> <li><a href="/wiki/Nutrient_pollution" title="Nutrient pollution">Nutrient pollution</a></li> <li><a href="/wiki/Ocean_acidification" title="Ocean acidification">Ocean acidification</a></li> <li><a href="/wiki/Oil_exploitation" class="mw-redirect" title="Oil exploitation">Oil exploitation</a></li> <li><a href="/wiki/Oil_exploration" class="mw-redirect" title="Oil exploration">Oil exploration</a></li> <li><a href="/wiki/Oil_spill" title="Oil spill">Oil spill</a></li> <li><a href="/wiki/Environmental_impact_of_pharmaceuticals_and_personal_care_products" title="Environmental impact of pharmaceuticals and personal care products">Pharmaceuticals</a></li> <li><a href="/wiki/Sewage" title="Sewage">Sewage</a> <ul><li><a href="/wiki/Septic_tank" title="Septic tank">Septic tanks</a></li> <li><a href="/wiki/Pit_latrine" title="Pit latrine">Pit latrine</a></li></ul></li> <li><a href="/wiki/Environmental_effects_of_shipping" class="mw-redirect" title="Environmental effects of shipping">Shipping</a></li> <li><a href="/wiki/Water_stagnation" title="Water stagnation">Stagnation</a></li> <li><a href="/wiki/Sulfur_water" title="Sulfur water">Sulfur water</a></li> <li><a href="/wiki/Surface_runoff" title="Surface runoff">Surface runoff</a></li> <li><a href="/wiki/Thermal_pollution" title="Thermal pollution">Thermal</a></li> <li><a href="/wiki/Turbidity" title="Turbidity">Turbidity</a></li> <li><a href="/wiki/Urban_runoff" title="Urban runoff">Urban runoff</a></li> <li><a href="/wiki/Water_quality" title="Water quality">Water quality</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="background:#fadcc5;width:1%;line-height:1.3em;">Topics</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Pollutant" title="Pollutant">Pollutants</a> <ul><li><a href="/wiki/Heavy_metals" class="mw-redirect" title="Heavy metals">Heavy metals</a></li> <li><a href="/wiki/Paint" title="Paint">Paint</a></li></ul></li> <li><a href="/wiki/Brain_health_and_pollution" title="Brain health and pollution">Brain health and pollution</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="background:#fadcc5;width:1%;line-height:1.3em;">Misc</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Area_source_pollution" title="Area source pollution">Area source</a></li> <li><a href="/wiki/Debris" title="Debris">Debris</a></li> <li><a href="/wiki/Dust" title="Dust">Dust</a></li> <li><a href="/wiki/Garbology" title="Garbology">Garbology</a></li> <li><a href="/wiki/Legacy_pollution" title="Legacy pollution">Legacy pollution</a></li> <li><a href="/wiki/Midden" title="Midden">Midden</a></li> <li><a href="/wiki/Point_source_pollution" title="Point source pollution">Point source</a></li> <li><a href="/wiki/Waste" title="Waste">Waste</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="background:#fadcc5;width:1%;line-height:1.3em;">Responses</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Cleaner_production" title="Cleaner production">Cleaner production</a></li> <li><a href="/wiki/Industrial_ecology" title="Industrial ecology">Industrial ecology</a></li> <li><a href="/wiki/Pollution_haven_hypothesis" title="Pollution haven hypothesis">Pollution haven hypothesis</a></li> <li><a href="/wiki/Pollutant_release_and_transfer_register" title="Pollutant release and transfer register">Pollutant release and transfer register</a></li> <li><a href="/wiki/Polluter_pays_principle" title="Polluter pays principle">Polluter pays principle</a></li> <li><a href="/wiki/Pollution_control" class="mw-redirect" title="Pollution control">Pollution control</a></li> <li><a href="/wiki/Waste_minimisation" title="Waste minimisation">Waste minimisation</a></li> <li><a href="/wiki/Zero_waste" title="Zero waste">Zero waste</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="background:#fadcc5;width:1%;line-height:1.3em;"><a href="/wiki/Category:Pollution-related_lists" title="Category:Pollution-related lists">Lists</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/List_of_pollution-related_diseases" title="List of pollution-related diseases">Diseases</a></li> <li><a href="/wiki/List_of_environmental_laws_by_country" title="List of environmental laws by country">Law by country</a></li> <li><a href="/wiki/List_of_most-polluted_cities_by_particulate_matter_concentration" title="List of most-polluted cities by particulate matter concentration">Most polluted cities</a></li> <li><a href="/wiki/List_of_least_polluted_cities_by_particulate_matter_concentration" class="mw-redirect" title="List of least polluted cities by particulate matter concentration">Least polluted cities by PM<sub>2.5</sub></a></li> <li><a href="/wiki/List_of_countries_by_air_pollution" title="List of countries by air pollution">Most polluted countries</a></li> <li><a href="/wiki/List_of_international_environmental_agreements" title="List of international environmental agreements">Treaties</a></li></ul> </div></td></tr><tr><td class="navbox-abovebelow" colspan="2" style="background:#fadcc5"><div><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> <a href="/wiki/Category:Pollution" title="Category:Pollution">Categories</a> (<a href="/wiki/Category:Pollution_by_country" title="Category:Pollution by country">by country</a>) <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> <a 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srcset="//upload.wikimedia.org/wikipedia/commons/thumb/3/37/People_icon.svg/24px-People_icon.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/3/37/People_icon.svg/32px-People_icon.svg.png 2x" data-file-width="100" data-file-height="100" /></span></span> <a href="/wiki/Wikipedia:WikiProject_Ecology" title="Wikipedia:WikiProject Ecology">WikiProject Ecology</a> <span class="nowrap"><span class="noviewer" typeof="mw:File"><a href="/wiki/File:Aegopodium_podagraria1_ies.jpg" class="mw-file-description"><img alt="icon" src="//upload.wikimedia.org/wikipedia/commons/thumb/b/bf/Aegopodium_podagraria1_ies.jpg/32px-Aegopodium_podagraria1_ies.jpg" decoding="async" width="32" height="28" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/bf/Aegopodium_podagraria1_ies.jpg/48px-Aegopodium_podagraria1_ies.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/bf/Aegopodium_podagraria1_ies.jpg/64px-Aegopodium_podagraria1_ies.jpg 2x" data-file-width="800" data-file-height="700" /></a></span> </span><a href="/wiki/Portal:Environment" title="Portal:Environment">Environment portal</a> <span class="nowrap"><span class="mw-image-border noviewer" typeof="mw:File"><span><img alt="icon" src="//upload.wikimedia.org/wikipedia/commons/thumb/6/6a/Earth_Day_Flag.png/32px-Earth_Day_Flag.png" decoding="async" width="32" height="21" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/6/6a/Earth_Day_Flag.png/48px-Earth_Day_Flag.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/6/6a/Earth_Day_Flag.png/64px-Earth_Day_Flag.png 2x" data-file-width="6000" data-file-height="4000" /></span></span> </span><a href="/wiki/Portal:Ecology" title="Portal:Ecology">Ecology portal</a></div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235"></div><div role="navigation" class="navbox" aria-labelledby="Natural_resources" style="padding:3px"><table class="nowraplinks hlist mw-collapsible autocollapse 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"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239400231"><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Natural_resources" title="Template:Natural resources"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Natural_resources" title="Template talk:Natural resources"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Natural_resources" title="Special:EditPage/Template:Natural resources"><abbr title="Edit this 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selflink">Index</a></li> <li><a href="/wiki/Indoor_air_quality" title="Indoor air quality">Indoor</a></li> <li><a href="/wiki/Air_quality_law" title="Air quality law">Law</a> <ul><li><a href="/wiki/Clean_Air_Act_(United_States)" title="Clean Air Act (United States)">Clean Air Act <span style="font-size:85%;">(US)</span></a></li></ul></li> <li><a href="/wiki/Ozone_depletion" title="Ozone depletion">Ozone depletion</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:7.0em;font-weight:normal;">Emissions</th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Airshed" title="Airshed">Airshed</a></li> <li><a href="/wiki/Emissions_trading" title="Emissions trading">Trading</a></li> <li><a href="/wiki/Reducing_emissions_from_deforestation_and_forest_degradation" class="mw-redirect" title="Reducing emissions from deforestation and forest degradation">Deforestation (REDD)</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/Energy" title="Energy">Energy</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/Bioenergy" title="Bioenergy">Bio</a></li> <li><a href="/wiki/Energy_law" title="Energy law">Law</a></li> <li><a href="/wiki/Energy_resources" class="mw-redirect" title="Energy resources">Resources</a></li> <li><a href="/wiki/Fossil_fuel" title="Fossil fuel">Fossil fuels</a> (<a href="/wiki/Fuel_gas" title="Fuel gas">gas</a>, <a href="/wiki/Peak_coal" title="Peak coal">peak coal</a>, <a href="/wiki/Peak_gas" title="Peak gas">peak gas</a>, <a href="/wiki/Peak_oil" title="Peak oil">peak oil</a>)</li> <li><a href="/wiki/Geothermal_energy" title="Geothermal energy">Geothermal</a></li> <li><a href="/wiki/Hydropower" title="Hydropower">Hydro</a></li> <li><a href="/wiki/Nuclear_power" title="Nuclear power">Nuclear</a></li> <li><a href="/wiki/Solar_energy" title="Solar energy">Solar</a> <ul><li><a href="/wiki/Sunlight" title="Sunlight">sunlight</a></li> <li><a href="/wiki/Shade_(shadow)" title="Shade (shadow)">shade</a></li></ul></li> <li><a href="/wiki/Wind_power" title="Wind power">Wind</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Land" title="Land">Land</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/Agricultural_land" title="Agricultural land">Agricultural</a> <ul><li><a href="/wiki/Arable_land" title="Arable land">arable</a> <ul><li><a href="/wiki/Peak_farmland" title="Peak farmland">peak farmland</a></li></ul></li></ul></li> <li><a href="/wiki/Land_degradation" title="Land degradation">Degradation</a></li> <li><a href="/wiki/Field_(agriculture)" title="Field (agriculture)">Field</a></li> <li><a href="/wiki/Landscape" title="Landscape">Landscape</a> <ul><li><a href="/wiki/Cityscape" title="Cityscape">cityscape</a></li> <li><a href="/wiki/Seascape" title="Seascape">seascape</a></li> <li><a href="/wiki/Soundscape" title="Soundscape">soundscape</a></li> <li><a href="/wiki/Viewshed" title="Viewshed">viewshed</a></li></ul></li> <li><a href="/wiki/Land_law" title="Land law">Law</a> <ul><li><a href="/wiki/Property_law" title="Property law">property</a></li></ul></li> <li><a href="/wiki/Land_management" title="Land management">Management</a> <ul><li><a href="/wiki/Habitat_conservation" title="Habitat conservation">habitat conservation</a></li></ul></li> <li><a href="/wiki/Mineral" title="Mineral">Minerals</a> <ul><li><a href="/wiki/Gemstone" title="Gemstone">gemstone</a></li> <li><a href="/wiki/Industrial_mineral" title="Industrial mineral">industrial</a></li> <li><a href="/wiki/Ore" title="Ore">ore</a> <ul><li><a href="/wiki/Metal" title="Metal">metal</a></li></ul></li> <li><a href="/wiki/Mining" title="Mining">mining</a> <ul><li><a href="/wiki/Mining_law" title="Mining law">law</a></li> <li><a href="/wiki/Sand_mining" title="Sand mining">sand</a></li></ul></li> <li><a href="/wiki/Peak_minerals" title="Peak minerals">peak</a> <ul><li><a href="/wiki/Peak_copper" class="mw-redirect" title="Peak copper">copper</a></li> <li><a href="/wiki/Peak_phosphorus" class="mw-redirect" title="Peak phosphorus">phosphorus</a></li></ul></li> <li><a href="/wiki/Mineral_rights" title="Mineral rights">rights</a></li></ul></li> <li><a href="/wiki/Soil" title="Soil">Soil</a> <ul><li><a href="/wiki/Soil_conservation" title="Soil conservation">conservation</a></li> <li><a href="/wiki/Soil_fertility" title="Soil fertility">fertility</a></li> <li><a href="/wiki/Soil_health" title="Soil health">health</a></li> <li><a href="/wiki/Soil_resilience" title="Soil resilience">resilience</a></li></ul></li> <li><a href="/wiki/Land_use" title="Land use">Use</a> <ul><li><a href="/wiki/Land-use_planning" title="Land-use planning">planning</a></li> <li><a href="/wiki/Open_space_reserve" title="Open space reserve">reserve</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Life" title="Life">Life</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/Biodiversity" title="Biodiversity">Biodiversity</a></li> <li><a href="/wiki/Bioprospecting" title="Bioprospecting">Bioprospecting</a> <ul><li><a href="/wiki/Biopiracy" title="Biopiracy">biopiracy</a></li></ul></li> <li><a href="/wiki/Biosphere" title="Biosphere">Biosphere</a></li> <li><a href="/wiki/Bushfood" class="mw-redirect" title="Bushfood">Bushfood</a></li> <li><a href="/wiki/Bushmeat" title="Bushmeat">Bushmeat</a></li> <li><a href="/wiki/Fishery" title="Fishery">Fisheries</a> <ul><li><a href="/wiki/Climate_change_and_fisheries" title="Climate change and fisheries">climate change</a></li> <li><a href="/wiki/Fisheries_law" title="Fisheries law">law</a></li> <li><a href="/wiki/Fisheries_management" title="Fisheries management">management</a></li></ul></li> <li><a href="/wiki/Forest" title="Forest">Forests</a> <ul><li><a href="/wiki/Forest_genetic_resources" title="Forest genetic resources">genetic resources</a></li> <li><a href="/wiki/Forestry_law" title="Forestry law">law</a></li> <li><a href="/wiki/Forest_management" title="Forest management">management</a></li> <li><a href="/wiki/Non-timber_forest_product" title="Non-timber forest product">non-timber products</a></li></ul></li> <li><a href="/wiki/Game_(food)" class="mw-redirect" title="Game (food)">Game</a> <ul><li><a href="/wiki/Game_law" title="Game law">law</a></li></ul></li> <li><a href="/wiki/Marine_conservation" title="Marine conservation">Marine conservation</a></li> <li><a href="/wiki/Meadow" title="Meadow">Meadow</a></li> <li><a href="/wiki/Pasture" title="Pasture">Pasture</a></li> <li><a href="/wiki/Plant" title="Plant">Plants</a> <ul><li><a href="/wiki/Plant_Treaty" class="mw-redirect" title="Plant Treaty">FAO Plant Treaty</a></li> <li><a href="/wiki/Food" title="Food">food</a></li> <li><a href="/wiki/Plant_genetic_resources" title="Plant genetic resources">genetic resources</a></li> <li><a href="/wiki/Gene_bank" title="Gene bank">gene banks</a></li> <li><a href="/wiki/List_of_plants_used_in_herbalism" title="List of plants used in herbalism">herbal medicines</a></li> <li><a href="/wiki/UPOV" class="mw-redirect" title="UPOV">UPOV Convention</a></li> <li><a href="/wiki/Wood" title="Wood">wood</a></li></ul></li> <li><a href="/wiki/Rangeland" title="Rangeland">Rangeland</a></li> <li><a href="/wiki/Seed_bank" title="Seed bank">Seed bank</a></li> <li><a href="/wiki/Wildlife" title="Wildlife">Wildlife</a> <ul><li><a href="/wiki/Wildlife_conservation" title="Wildlife conservation">conservation</a></li> <li><a href="/wiki/Wildlife_management" title="Wildlife management">management</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Water" title="Water">Water</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:7.0em;font-weight:normal;">Types / location</th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Aquifer" title="Aquifer">Aquifer</a> <ul><li><a href="/wiki/Aquifer_storage_and_recovery" title="Aquifer storage and recovery">storage and recovery</a></li></ul></li> <li><a href="/wiki/Drinking_water" title="Drinking water">Drinking</a></li> <li><a href="/wiki/Fresh_water" title="Fresh water">Fresh</a></li> <li><a href="/wiki/Groundwater" title="Groundwater">Groundwater</a> <ul><li><a href="/wiki/Groundwater_pollution" title="Groundwater pollution">pollution</a></li> <li><a href="/wiki/Groundwater_recharge" title="Groundwater recharge">recharge</a></li> <li><a href="/wiki/Groundwater_remediation" title="Groundwater remediation">remediation</a></li></ul></li> <li><a href="/wiki/Hydrosphere" title="Hydrosphere">Hydrosphere</a></li> <li><a href="/wiki/Ice" title="Ice">Ice</a> <ul><li><a href="/wiki/Iceberg" title="Iceberg">bergs</a></li> <li><a href="/wiki/Glacier" title="Glacier">glacial</a></li> <li><a href="/wiki/Polar_ice_cap" title="Polar ice cap">polar</a></li></ul></li> <li><a href="/wiki/Irrigation" title="Irrigation">Irrigation</a> <ul><li><i><a href="/wiki/Huerta" title="Huerta">huerta</a></i></li></ul></li> <li><a href="/wiki/Marine_resources" title="Marine resources">Marine</a></li> <li><a href="/wiki/Rain" title="Rain">Rain</a> <ul><li><a href="/wiki/Rainwater_harvesting" title="Rainwater harvesting">harvesting</a></li></ul></li> <li><a href="/wiki/Stormwater" title="Stormwater">Stormwater</a></li> <li><a href="/wiki/Surface_water" title="Surface water">Surface water</a></li> <li><a href="/wiki/Sewage" title="Sewage">Sewage</a> <ul><li><a href="/wiki/Reclaimed_water" title="Reclaimed water">reclaimed water</a></li></ul></li> <li><a href="/wiki/Drainage_basin" title="Drainage basin">Watershed</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:7.0em;font-weight:normal;">Aspects</th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Desalination" title="Desalination">Desalination</a></li> <li><a href="/wiki/Flood" title="Flood">Floods</a></li> <li><a href="/wiki/Water_law" class="mw-redirect" title="Water law">Law</a></li> <li><a href="/wiki/Leaching_(agriculture)" title="Leaching (agriculture)">Leaching</a></li> <li><a href="/wiki/Sanitation" title="Sanitation">Sanitation</a> <ul><li><a href="/wiki/Improved_sanitation" title="Improved sanitation">improved</a></li></ul></li> <li><a href="/wiki/Water_scarcity" title="Water scarcity">Scarcity</a></li> <li><a href="/wiki/Water_security" title="Water security">Security</a></li> <li><a href="/wiki/Water_supply" title="Water supply">Supply</a></li> <li><a href="/wiki/Water_efficiency" title="Water efficiency">Efficiency</a></li> <li><a href="/wiki/Water_conflict" title="Water conflict">Conflict</a></li> <li><a href="/wiki/Water_conservation" title="Water conservation">Conservation</a></li> <li><a href="/wiki/Peak_water" title="Peak water">Peak water</a></li> <li><a href="/wiki/Water_pollution" title="Water pollution">Pollution</a></li> <li><a href="/wiki/Water_privatization" title="Water privatization">Privatization</a></li> <li><a href="/wiki/Water_quality" title="Water quality">Quality</a></li> <li><a href="/wiki/Water_right" title="Water right">Right</a></li> <li><a href="/wiki/Water_resources" title="Water resources">Resources</a> <ul><li><a href="/wiki/Improved_water_source" title="Improved water source">improved</a></li> <li><a href="/wiki/Water_resource_policy" title="Water resource policy">policy</a></li></ul></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Related</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><td colspan="2" class="navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Commons" title="Commons">Commons</a> <ul><li><a href="/wiki/Enclosure" title="Enclosure">enclosure</a></li> <li><a href="/wiki/Global_commons" title="Global commons">global</a></li> <li><a href="/wiki/Common_land" title="Common land">land</a></li> <li><a href="/wiki/Tragedy_of_the_commons" title="Tragedy of the commons">tragedy of</a></li></ul></li> <li><a href="/wiki/Natural_resource_economics" title="Natural resource economics">Economics</a> <ul><li><a href="/wiki/Ecological_economics" title="Ecological economics">ecological</a></li> <li><a href="/wiki/Land_(economics)" title="Land (economics)">land</a></li></ul></li> <li><a href="/wiki/Ecosystem_services" class="mw-redirect" title="Ecosystem services">Ecosystem services</a></li> <li><a href="/wiki/Exploitation_of_natural_resources" title="Exploitation of natural resources">Exploitation</a> <ul><li><a href="/wiki/Overexploitation" title="Overexploitation">overexploitation</a></li> <li><a href="/wiki/Earth_Overshoot_Day" title="Earth Overshoot Day">Earth Overshoot Day</a></li></ul></li> <li><a href="/wiki/Natural_resource_management" title="Natural resource management">Management</a> <ul><li><a href="/wiki/Adaptive_management" title="Adaptive management">adaptive</a></li></ul></li> <li><a href="/wiki/Natural_capital" title="Natural capital">Natural capital</a> <ul><li><a href="/wiki/Natural_capital_accounting" title="Natural capital accounting">accounting</a></li> <li><a href="/wiki/Environmental_good" title="Environmental good">good</a></li></ul></li> <li><a href="/wiki/Natural_heritage" title="Natural heritage">Natural heritage</a></li> <li><a href="/wiki/Nature_reserve" title="Nature reserve">Nature reserve</a> <ul><li><a href="/wiki/Remnant_natural_area" title="Remnant natural area">remnant natural area</a></li></ul></li> <li><a href="/wiki/Systems_ecology" title="Systems ecology">Systems ecology</a></li> <li><a href="/wiki/Urban_ecology" title="Urban ecology">Urban ecology</a></li> <li><a href="/wiki/Wilderness" title="Wilderness">Wilderness</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:7.0em;font-weight:normal;"><a href="/wiki/Resource" title="Resource">Resource</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div 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