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var items = innerMenu.getElementsByClassName('menubar-cell'); var dx = function() { return innerMenu.getBoundingClientRect().width - window.innerWidth;}; for (let i = items.length - 1; i >= 0 && dx() >= 0; i--) { items[i].classList.add("no-menu-text"); } }()); } catch (e) { console.error(e) } try { navmenu.init(); } catch (e) {} </script><div class='h1section'><h1><div id='h1header1' style='padding:2px;padding:5px 0;font-family:"Noto Serif",Cambria,"Palatino Linotype","Book Antiqua","URW Palladio L",serif;;;' i18n>Air Quality experiments on alternative sensors and prediction model</div></h1></div><script type='text/javascript'> ; if (!isMobileUA) { fitLine('#h1header1',.88,{maxfs:45}); }; </script><style> .section-outer { text-align: initial; } .section-content { max-width: 95%; width: 1100px; font-size: 18px; min-height: 300px; text-align: initial; margin-top: 10px; margin-bottom: 10px; line-height: 1.8; margin-left: auto; margin-right: auto; } .section-content-tight { min-height: 0px; } .section-content-alt { background-color: #f0f0f0; border-top: 1px solid #ccc; border-bottom: 1px solid #ddd } ; .section-banner { background-size: 100%; background: url(https://aqicn.org/images//bluesky-banner-panoramic.jpg) no-repeat center bottom #eee; margin-top: -2px; z-index: -1; border-bottom: 1px solid #888; width: 100%; } .h2-title { font-family: inherit; font-size: 1.1em; overflow: hidden; text-align: center; text-transform: capitalize; } .h2-title:before, .h2-title:after { background-color: #ddd; content: ''; display: inline-block; height: 1px; position: relative; vertical-align: middle; width: 50%; } .h2-title:before { right: 0.5em; margin-left: -50%; } .h2-title:after { left: 0.5em; margin-right: -50%; } @media only screen and (max-width: 800px) { .section-content { line-height: 1.6; max-width: 98%; min-height: 10px; } .section-banner { display: none; } } </style> <div class='whitebody' style='font-family:"Noto Serif",Cambria,"Palatino Linotype","Book Antiqua","URW Palladio L",serif;'><div class='section-outer'><div class='section-content' ><div id="gtrans-div-id" style="float:right" class="gtrans-div"></div><script>try { googleTranslate(); } catch (e) {}</script> <script src='/jscripts/moment/bundle.min.js?_=20200103.150752&type=script'></script><script src='/jscripts/d3/d3.min.js?_=20190418.093123&type=script'></script><script src='/air/view/sensor/js/sensolib.js?_=20200517.131233&type=script'></script><script src='/air/view/sensor/js/sensor-bundle.min.js?_=20220515.202405&type=script'></script><link href='/air/view/sensor/js/sensor-bundle.min.css?_=20190418.093129&type=css' rel='stylesheet'/> <style > .entry-content { line-height: 1.5; } div.entry-content p:first-child:first-letter { float:left; font-size:3em; margin-right:.06em; line-height:90%; } blockquote { background: url(https://aqicn.org/images/blockquote.png) no-repeat; color: #a5a4a4; font-style: italic; margin: 30px; padding: 3px 100px 3px 80px; } </style> <div style='float:right;padding-left:20px;text-align:center;max-width:33%;'><br><br><img src='/air/experiments/images/aqi.png' width=300 style='max-width:100%'><br><br><br><img src='/air/experiments/images/pollution.png' width=286 style='max-width:100%'><br><br><br><img src='/air/experiments/images/aqiscale.png' width=300 style='max-width:100%'><br></div><br><div class='entry-content'><p>Air Quality monitoring has existed since the 70's, and surprisingly, the equipement used nowdays is still based on the same technology as in the 70's, i.e Beta Attenation Monitors (aka BAM). Almost 50 years later, in 2014, the progress in technology is now allowing us to use new solutions to monitor the Air Quality, with a quality as good as the BAM monitors, but at a much more affordable cost.<br><br>The <a href='//aqicn.org/'>World Air Quality Index</a> project team is involved in understanding, assessing and verifying those new technologies, and this to ensure that they can realiably replace the more traditional BAM-based setups. In this page, you wil find the list of on-going, planned and concluded experiements.<center><br>-<svg xmlns="http://www.w3.org/2000/svg" width="28" height="28" version="1" viewBox="0 0 26 26" enable-background="new 0 0 26 26"><path d="M 15.65625 -0.03125 C 14.280846 -0.03760636 12.828752 0.09254274 11.3125 0.40625 C 8.28651 1.0323169 5.7746616 2.1709106 3.96875 3.59375 C 2.3885774 4.8387345 1.3097647 6.3321654 1.0625 7.96875 A 1.0001 1.0001 0 0 0 1 8.40625 C 1 8.4709766 0.99753847 8.5296394 1 8.59375 C 0.99939321 8.6245955 1 8.6565744 1 8.6875 C 1.0067678 8.8049913 1.0164368 8.9159604 1.03125 9.03125 C 1.0536237 9.2185949 1.1014372 9.4156735 1.15625 9.59375 C 1.4590854 10.826485 2.2046296 11.91918 3.21875 12.78125 C 4.0779092 13.511593 5.1369309 14.083861 6.3125 14.53125 A 1.0001 1.0001 0 0 0 6.53125 14.9375 C 8.1339345 16.910035 12.101162 19.118434 18.1875 18.59375 A 1.0043849 1.0043849 0 0 0 18 16.59375 C 14.906411 16.860439 12.500325 16.269357 10.78125 15.5 C 14.30154 15.772761 18.245209 15.070028 21.71875 12.96875 A 1.0021949 1.0021949 0 1 0 20.6875 11.25 C 16.887924 13.548509 12.317006 14.000584 8.78125 13.21875 C 8.6725971 13.194724 8.5753958 13.151278 8.46875 13.125 C 10.108287 13.189898 11.88322 13.060799 13.6875 12.6875 C 16.718701 12.060355 19.36029 10.886006 21.21875 9.4375 C 23.067114 7.9968631 24.272087 6.1533076 23.875 4.21875 C 23.8732 4.20861 23.8769 4.197602 23.875 4.1875 C 23.513143 2.2541955 21.685558 1.0369822 19.4375 0.4375 C 18.307598 0.13619269 17.031654 -0.02489364 15.65625 -0.03125 z M 15.65625 1.96875 C 16.883971 1.97489 18.004902 2.1263073 18.9375 2.375 C 20.802695 2.8723854 21.754612 3.7133252 21.90625 4.5625 A 1.0001 1.0001 0 0 0 21.9375 4.625 C 22.12047 5.4788616 21.54154 6.6735055 20 7.875 C 18.45846 9.0764945 16.081299 10.145895 13.3125 10.71875 C 10.546306 11.291066 7.7660826 11.269646 5.8125 10.78125 C 4.8357087 10.537052 4.0847823 10.157122 3.625 9.78125 C 3.3682882 9.5713881 3.1893221 9.3858538 3.09375 9.1875 C 3.0413411 8.9743851 3.0082478 8.7545393 3 8.53125 C 3.0633474 7.4789308 3.7648202 6.2771492 5.1875 5.15625 C 6.6815884 3.9790894 8.91349 2.9489331 11.6875 2.375 C 13.071248 2.0887073 14.428529 1.9626064 15.65625 1.96875 z M 15.96875 3.65625 C 14.93792 3.617106 13.843984 3.69192 12.71875 3.90625 A 1.0001 1.0001 0 0 0 12.6875 3.9375 C 9.8940815 4.582135 7.6159262 5.8506824 6.5625 7.5625 A 1.0001 1.0001 0 1 0 8.25 8.625 C 8.7942179 7.740646 10.701734 6.434394 13.09375 5.875 C 13.10453 5.87295 13.11421 5.87702 13.125 5.875 C 15.064267 5.5112859 17.031887 5.6468794 18.03125 6.03125 A 1.0040202 1.0040202 0 0 0 18.75 4.15625 C 17.952461 3.8495042 16.99958 3.6953943 15.96875 3.65625 z M 9.15625 17.59375 A 1.0001 1.0001 0 0 0 8.5625 19.25 C 8.5625 19.25 11.033033 22.015963 15.53125 21.90625 A 1.0004882 1.0004882 0 1 0 15.46875 19.90625 C 11.766967 19.996537 10.0625 17.9375 10.0625 17.9375 A 1.0001 1.0001 0 0 0 9.15625 17.59375 z M 8.125 20.1875 A 1.0001 1.0001 0 0 0 7.40625 21.65625 C 7.40625 21.65625 8.6869767 23.974979 11.65625 24.09375 A 1.001098 1.001098 0 0 0 11.75 22.09375 C 9.7192733 22.012521 9.1875 20.75 9.1875 20.75 A 1.0001 1.0001 0 0 0 8.21875 20.1875 A 1.0001 1.0001 0 0 0 8.125 20.1875 z M 7.59375 23.0625 A 1.0001 1.0001 0 0 0 7.4375 23.09375 A 1.0001 1.0001 0 0 0 6.9375 23.34375 C 6.9375 23.34375 6.19375 24 5.09375 24 A 1.0001 1.0001 0 1 0 5.09375 26 C 6.99375 26 8.28125 24.84375 8.28125 24.84375 A 1.0001 1.0001 0 0 0 7.59375 23.0625 z" color="#000" ></path></svg>-<br><br></center><h3>On-going experiments</h3><ul><li><a href='/faq/2013-09-08/dylos-air-particule-counter-experimentation-part-1/'>The Dylos Air Particule counter</a>: Can it be used as a substitue of more expensive BAM monitors? A one-year long experiments on trying to correlate Dylos and BAM data in Beijing. </ul><ul><li><a href='/sensor/shinyei/'>Low-cost shinyei and samyoung Sensors</a>: Low cost sensors are used in many of the 'Air Sensor Toys' appearing on Internet. But, can those ultra low-cost sensor provide any good information on air quality? Can any reliable AQI be deducted?</ul><br><h3>Concluded experiments</h3><ul><li><a href='/experiments/what-is-the-dylos-monitor-actually-measuring/'>Deducting PM2.5 and PM10 concentrations from the Dylos monitor readings:</a> An experiment to understand how to use the Dylos real-time readings to deduct, with high confidence, PM2.5 and PM10 concentrations.</a></ul><ul><li><a href='/experiments/south-korea-pm25-air-quality/'>Estimating PM2.5 AQI when only PM10 sensors are available.</a> Experimentation and real-time simulation applied for South Korea.</ul><ul><li><a href='/experiments/haier-air-box/'>Haier Air Box</a>: A reverse engineering of the Haier AirBox air quality sensor for the smart home. </ul><br><h3>Planned experiments</h3><ul><li>Correlatation between PM10, PM2.5 and the local dust type. An extension of the <a href='/experiments/south-korea-pm25-air-quality/' style='color:black;'><i>PM2.5 AQI estimation from PM10 AQI</i></a> experiment. </ul><ul><li>The GFS Wind forecast: Is it really accurate? How do actual and predicted data differ?</ul><ul><li>Predicting Air Quality: using the GFS wind forecast to predict Air Pollution flux</ul><center><br>-<svg xmlns="http://www.w3.org/2000/svg" width="28" height="28" version="1" viewBox="0 0 26 26" enable-background="new 0 0 26 26"><path d="M 15.65625 -0.03125 C 14.280846 -0.03760636 12.828752 0.09254274 11.3125 0.40625 C 8.28651 1.0323169 5.7746616 2.1709106 3.96875 3.59375 C 2.3885774 4.8387345 1.3097647 6.3321654 1.0625 7.96875 A 1.0001 1.0001 0 0 0 1 8.40625 C 1 8.4709766 0.99753847 8.5296394 1 8.59375 C 0.99939321 8.6245955 1 8.6565744 1 8.6875 C 1.0067678 8.8049913 1.0164368 8.9159604 1.03125 9.03125 C 1.0536237 9.2185949 1.1014372 9.4156735 1.15625 9.59375 C 1.4590854 10.826485 2.2046296 11.91918 3.21875 12.78125 C 4.0779092 13.511593 5.1369309 14.083861 6.3125 14.53125 A 1.0001 1.0001 0 0 0 6.53125 14.9375 C 8.1339345 16.910035 12.101162 19.118434 18.1875 18.59375 A 1.0043849 1.0043849 0 0 0 18 16.59375 C 14.906411 16.860439 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9.5713881 3.1893221 9.3858538 3.09375 9.1875 C 3.0413411 8.9743851 3.0082478 8.7545393 3 8.53125 C 3.0633474 7.4789308 3.7648202 6.2771492 5.1875 5.15625 C 6.6815884 3.9790894 8.91349 2.9489331 11.6875 2.375 C 13.071248 2.0887073 14.428529 1.9626064 15.65625 1.96875 z M 15.96875 3.65625 C 14.93792 3.617106 13.843984 3.69192 12.71875 3.90625 A 1.0001 1.0001 0 0 0 12.6875 3.9375 C 9.8940815 4.582135 7.6159262 5.8506824 6.5625 7.5625 A 1.0001 1.0001 0 1 0 8.25 8.625 C 8.7942179 7.740646 10.701734 6.434394 13.09375 5.875 C 13.10453 5.87295 13.11421 5.87702 13.125 5.875 C 15.064267 5.5112859 17.031887 5.6468794 18.03125 6.03125 A 1.0040202 1.0040202 0 0 0 18.75 4.15625 C 17.952461 3.8495042 16.99958 3.6953943 15.96875 3.65625 z M 9.15625 17.59375 A 1.0001 1.0001 0 0 0 8.5625 19.25 C 8.5625 19.25 11.033033 22.015963 15.53125 21.90625 A 1.0004882 1.0004882 0 1 0 15.46875 19.90625 C 11.766967 19.996537 10.0625 17.9375 10.0625 17.9375 A 1.0001 1.0001 0 0 0 9.15625 17.59375 z M 8.125 20.1875 A 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href='/publishingdata/'>publishing data</a> guide.<center><br>-<svg xmlns="http://www.w3.org/2000/svg" width="28" height="28" version="1" viewBox="0 0 26 26" enable-background="new 0 0 26 26"><path d="M 15.65625 -0.03125 C 14.280846 -0.03760636 12.828752 0.09254274 11.3125 0.40625 C 8.28651 1.0323169 5.7746616 2.1709106 3.96875 3.59375 C 2.3885774 4.8387345 1.3097647 6.3321654 1.0625 7.96875 A 1.0001 1.0001 0 0 0 1 8.40625 C 1 8.4709766 0.99753847 8.5296394 1 8.59375 C 0.99939321 8.6245955 1 8.6565744 1 8.6875 C 1.0067678 8.8049913 1.0164368 8.9159604 1.03125 9.03125 C 1.0536237 9.2185949 1.1014372 9.4156735 1.15625 9.59375 C 1.4590854 10.826485 2.2046296 11.91918 3.21875 12.78125 C 4.0779092 13.511593 5.1369309 14.083861 6.3125 14.53125 A 1.0001 1.0001 0 0 0 6.53125 14.9375 C 8.1339345 16.910035 12.101162 19.118434 18.1875 18.59375 A 1.0043849 1.0043849 0 0 0 18 16.59375 C 14.906411 16.860439 12.500325 16.269357 10.78125 15.5 C 14.30154 15.772761 18.245209 15.070028 21.71875 12.96875 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(!isMobileUA) { fitLine('#h1header2',.88,{maxfs:45}); }; </script><div class='whitebody' style='font-family:"Noto Serif",Cambria,"Palatino Linotype","Book Antiqua","URW Palladio L",serif;'><div class='section-outer'><div class='section-content' > <center>About the Air Quality Levels<br> <br> <style type="text/css"> #legend-full table.infoaqitable { line-height: 1.5; background-color: white; max-width: 1000px; width: 95%; margin: 0px; border: 1px solid black; cursor: pointer; } #legend-full table.infoaqitable td { padding: 5px; font-size: 15px; text-shadow: none; } #legend-full .aqiwtxt { color: #ffffff; } #legend-full .aqibtxt { color: #000000; } @media only screen and (max-width: 800px) { #legend-full table.infoaqitable { width: 98%; } } @media only screen and (max-width: 800px) { #legend-full table.infoaqitable td { display: block; } #legend-full table.infoaqitable td:nth-child(1) { display: inline-block; font-size: 1.2em; } #legend-full table.infoaqitable td:nth-child(2) { display: inline-block; font-weight: 800; font-size: 1.2em; } } </style> <div id='legend-full' onclick='window.location="/scale/"'> <table class="infoaqitable cautionary"> <thead> <tr> <td>AQI</td> <td i18n='generic'>Air Pollution Level</td> <td i18n='generic'>Health Implications</td> <td i18n='generic'>Cautionary Statement (for PM2.5)</td> </tr> </thead> <tr style="background-color:#009966;"> <td class='aqiwtxt' nowrap="true">0 - 50</td> <td class='aqiwtxt' i18n='generic'>Good</td> <td class='aqiwtxt' i18n='generic'>Air quality is considered satisfactory, and air pollution poses little or no risk</td> <td class='aqiwtxt' i18n='generic'>None</td> </tr> <tr style="background-color:#ffde33" class='aqibtxt'> <td class='aqibtxt' nowrap="true">51 -100</td> <td class='aqibtxt' i18n='generic'>Moderate</td> <td class='aqibtxt' i18n='generic'>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 class='aqibtxt' i18n='generic'>Active children and adults, and people with respiratory disease, such as asthma, should limit prolonged outdoor exertion.</td> </tr> <tr style="background-color:#ff9933;"> <td class='aqibtxt' nowrap="true">101-150</td> <td class='aqibtxt' i18n='generic'>Unhealthy for Sensitive Groups</td> <td class='aqibtxt' i18n='generic'>Members of sensitive groups may experience health effects. The general public is not likely to be affected.</td> <td class='aqibtxt' i18n='generic'>Active children and adults, and people with respiratory disease, such as asthma, should limit prolonged outdoor exertion.</td> </tr> <tr style="background-color:#cc0033;"> <td class='aqiwtxt' nowrap="true">151-200</td> <td class='aqiwtxt' i18n='generic'>Unhealthy</td> <td class='aqiwtxt' i18n='generic'>Everyone may begin to experience health effects; members of sensitive groups may experience more serious health effects</td> <td class='aqiwtxt' i18n='generic'>Active children and adults, and people with respiratory disease, such as asthma, should avoid prolonged outdoor exertion; everyone else, especially children, should limit prolonged outdoor exertion</td> </tr> <tr style="background-color:#660099;"> <td class='aqiwtxt' nowrap="true">201-300</td> <td class='aqiwtxt' i18n='generic'>Very Unhealthy</td> <td class='aqiwtxt' i18n='generic'>Health warnings of emergency conditions. The entire population is more likely to be affected.</td> <td class='aqiwtxt' i18n='generic'>Active children and adults, and people with respiratory disease, such as asthma, should avoid all outdoor exertion; everyone else, especially children, should limit outdoor exertion.</td> </tr> <tr style="background-color:#7e0023;"> <td class='aqiwtxt' nowrap="true">300+</td> <td class='aqiwtxt' i18n='generic'>Hazardous</td> <td class='aqiwtxt' i18n='generic'>Health alert: everyone may experience more serious health effects</td> <td class='aqiwtxt' i18n='generic'>Everyone should avoid all outdoor exertion</td> </tr> </table></div><br>To know more about Air Quality and Pollution, check the <a href='http://en.wikipedia.org/wiki/Air_quality'>wikipedia Air Quality topic</a> or the <a href='http://www.airnow.gov/index.cfm?action=aqibasics.aqi'>airnow guide to Air Quality and Your Health</a>.<br><br>For very useful health advices of Beijing Doctor Richard Saint Cyr MD, check <a href='http://www.myhealthbeijing.com/'>www.myhealthbeijing.com</a> blog.<br><br></center></div></div></div> <center> <br>  <ins class="adsbygoogle" style="display:block" data-ad-client="ca-pub-0281575029452656" data-ad-slot="2455076269" data-ad-format="auto"></ins> <script>(adsbygoogle = window.adsbygoogle || []).push({});</script> <style type='text/css'> .usage-notice { line-height:1.5; max-width:95%; width:1000px; margin-top:10px; padding:5px; font-size: 15px; background-color:#ffffff; text-shadow: 1px 1px 1px white; -webkit-box-shadow: 1px 1px 8px -3px rgba(0,0,0,0.3); } </style> <div class="textshadowwhite usage-notice" style=''> <b>Usage Notice</b>: All the Air Quality data are unvalidated at the time of publication, and due to quality assurance these data may be amended, without notice, at any time. 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id='settings-temp-label-off'>Fahrenheit</span> </span> </center> </td> <td> <div class="onoffswitch" onclick='settingsMenu.click("temp")'> <input type="checkbox" name="onoffswitch" class="onoffswitch-checkbox" id="settings-temp" checked> <label class="onoffswitch-label" for="myonoffswitch"> <span class="onoffswitch-inner"></span> <span class="onoffswitch-switch"></span> </label> </div> </table> </center> <br> </div> <div style='display:none;height:0px;' id='settingsdiv-arrow'><div style='width: 0; height: 0; border: 7px solid transparent;top:0px;border-top: 7px solid #fff;position:relative;;margin-left:100px;'></div></div> </div> <link rel='stylesheet' type='text/css' href='https://aqicn.org/air-cache/generic/scripts/dist/navmenu.css?_=20250118.191236' /><script async src='https://aqicn.org/air-cache/generic/scripts/dist/navmenu.js?_=20250121.194619' type='text/javascript'></script> <script type="text/javascript"> fitLine(".link",.9); </script> <script src='https://aqicn.org/air-cache/jquery-3.7.1.min.js?_=20250116.195014' type='text/javascript'></script> <script type="text/javascript"> function initTime() { if (isMobileUA) return; function setTimeText() { var minutes = new Date().getMinutes(); var hours = new Date().getHours(); var time = ( hours < 10 ? "0" : "" ) + hours; time += ":"+( minutes < 10 ? "0" : "" ) + minutes; var ot = document.getElementById("ClockTime"); if (ot) ot.innerHTML = time; } setInterval( function() { setTimeText() }, 1000*60*15 ); setTimeText(); }; aqi18n.register('aqi-implication-0-50',"Air quality is considered satisfactory, and air pollution poses little or no risk");aqi18n.register('aqi-level-0-50',"Good");aqi18n.register('aqi-implication-50-100',"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.");aqi18n.register('aqi-level-50-100',"Moderate");aqi18n.register('aqi-implication-100-150',"Members of sensitive groups may experience health effects. The general public is not likely to be affected.");aqi18n.register('aqi-level-100-150',"Unhealthy for sensitive groups");aqi18n.register('aqi-level-100-150-html',"<div style='font-size:66%'>Unhealthy for sensitive groups<\/div>");aqi18n.register('aqi-implication-150-200',"Everyone may begin to experience health effects; members of sensitive groups may experience more serious health effects");aqi18n.register('aqi-level-150-200',"Unhealthy");aqi18n.register('aqi-implication-200-300',"Health warnings of emergency conditions. 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