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Air Sensor Toolbox

Past Research Projects Using Air Sensor Technology

EPA conducts research to advance the development and application of air sensor technologies. Researchers have evaluated custom-built air sensor devices as well as commercially available air sensor technologies. Air sensors have been used in many studies in collaboration with states, communities, tribes, industry, and other groups. Research projects that have been completed are listed below.

Kansas City Transportation and Local-Scale Air Quality Study (KC-TRAQS)

KC-TRAQS was a field study conducted from 2018-2019 in southeast Kansas City, Kansas, to understand air pollution on a microscale, in an area impacted by multiple sources. Air measurements were collected using regulatory grade methods and instruments, air sensors, mobile monitoring, and citizen science.


KC-TRAQS Slideshow: New Measurement Technology Helps Community Learn About Air QualityExit

Village Green Project

The Village Green Project, conducted from 2013-2019, was a community-based research effort to demonstrate near real-time air monitoring technology and engage the public in learning about air quality. Researchers developed eight air quality monitoring systems built into park benches and deployed them in cities across the country in partnership with communities and organizations. The Village Green Project had an active educational component used by teachers, museums and others to educate youth about air quality in their communities.

Village Green Project

Wildland Fire Sensors Challenge

In 2017, EPA and five federal partners issued a challenge to promote innovation through the development of air sensor technologies that could improve smoke monitoring and provide air pollution data to protect public health. Winners of this challenge were awarded in 2018.

Wildland Fire Sensors Challenge

Air Monitoring in Puerto Rico

From 2016-2017, EPA collaborated with a community group in Peñuelas, Puerto Rico to measure local pollutant levels and understand local environmental conditions. Measurements were collected over five months using custom-built, portable air sensors. 

Journal Article on Spatial-Temporal Analysis of PM2.5 and NO2 Concentrations Collected Using Low-Cost Sensors in Peñuelas, Puerto Rico

CitySpace Project

The CitySpace Project was conducted from 2016-2017 to better understand how air sensors could be used when deployed as a network across a city to explore spatial variability in air pollution. Particulate matter sensors were deployed for approximately six months in Memphis, Tennessee.

Journal article on Examining spatiotemporal variability of urban particulate matter and application of high-time resolution data from a network of low-cost air pollution sensors

Sensor Scale Pilot Project

In 2016, EPA conducted a pilot project to evaluate a new tool called a “sensor scale.” This scale could be used with air sensors to help the public understand one-minute air quality data from air sensors and how to use those data for planning outdoor activities.

What Do My Sensor Readings Mean? Sensor Scale Pilot Project 

Community Air Sensor Network Project (CAIRSENSE)

The CAIRSENSE project , conducted from 2014-2016, was a multi-location study that evaluated long-term performance characteristics of air sensors and their limitations. A variety of particulate matter and gas-phase sensors were evaluated against regulatory-grade reference monitors under ambient conditions in Atlanta, Georgia, and Denver, Colorado.

Journal article on CAIRSENSE Atlanta (2014-2015)  

Journal article on CAIRSENSE Denver (2015-2016)

Ironbound Community Air Monitoring Project

In 2015, EPA collaborated with the Ironbound Community in Newark, New Jersey,  to characterize air pollution (specifically nitrogen dioxide and fine particulate matter) using custom-built portable air sensors operated by citizen scientists. The sensors also were evaluated against reference monitors under ambient conditions.

Journal article on Citizen Science Air Monitoring in the Ironbound Community

Report on Citizen Science Air Monitoring in the Ironbound Community

DISCOVER-AQ Air Sensor Evaluations

The DISCOVER-AQ Earth Venture Mission, conducted from 2011-2014, was a multi-location study led by NASA. During two month-long campaigns--one in 2013 in Houston, Texas, and the other in 2014 in Denver, Colorado --EPA evaluated the performance of gas-phase air sensors against reference monitors and deployed the sensors in a citizen science-operated network.

Journal article on Performance Evaluation and Community Application of Low-Cost Sensors for Ozone and Nitrogen Dioxide

Field and Laboratory Air Sensor Evaluations in the RTP Area

From 2012-2014, EPA conducted a number of field and laboratory air sensor performance evaluations at EPA’s campus in Research Triangle Park, North Carolina, or at a near-road sampling site in Raleigh, North Carolina. Sensors evaluated measured a variety of pollutants including particulate matter, ozone, nitrogen dioxide, and volatile organic compounds. The sensors were also evaluated against reference monitors under ambient or controlled laboratory conditions.

Next Generation Air Monitoring (NGAM) VOC Sensor Evaluation Report

Evaluation of Elm and Speck Sensors Report

Evaluation of Field-deployed Low-Cost PM Sensors Report

Sensor Evaluation Report