Comparative evaluation of low-cost particulate matter sensors

There is rising concern from the public due to exposure to particulate matter and the risks it poses to human health. In response, there is an increase in the use of low-cost air quality sensors LCS, as they are affordable, accessible and portable. These qualities make the sensors appealing not just for residential use, but also for research and educational purposes. However, there remain concerns about the ability of these sensors to accurately and reliably monitor PM levels in comparison to higher grade instruments. This study evaluates the performance of several LCS – Purple Air, Aeroqual, BlueSky, Canaree and Davies – in comparison to a reference high grade sensor – the TSI DustTrak. These LCS are tested in a range of different controlled environments (ambient and chamber) and aerosol characteristics [ambient, humidifier (water droplet aerosol) and combustion aerosol (incense)] to assess accuracy and precision. Simultaneous measurements were taken from the DustTrak sensors and the LCS, and their dataset was analyzed in terms of coefficient of determination (R2) and slope regression. The Dataset from the DustTrak sensors showed strong consistency with each other across all environments, establishing their reliability. Compared to the DustTraks, however, all the low-cost sensors underestimated PM concentrations. Among the low-cost sensors, the Purple Air sensors and the Aeroqual sensors demonstrated the best and most stable correlation with the DustTrak sensors. This work demonstrates the need for the expansion of air quality monitoring. While these sensors provide qualitative results that are acceptable, they should be used with an understanding of their limitations in providing quantitative results. They are not replacements for industry-grade sensors but are appropriate for use in specific community and educational purposes. The results point to a continued use of sensors, like the Purple Air Sensors, for citizen use, while also emphasizing the need for further work in quality air pollution monitors.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Environ Engr in Civil Engr

Grantor

University of Illinois Urbana-Champaign

Year dc:date

2025

Author dc:creator

• Nweke, Oluchi

Contributors dc:contributor

• Vishal, Verma

• Air Quality
• Low-cost Sensors
• Air Pollution
• Environmental Monitoring
• Public Heath

Statement dc:rights

• Copyright 2025 Oluchi Nweke

Language dc:language

en, eng

Handle dc:identifier

https://hdl.handle.net/2142/129996

OAI record oai:identifier

https://www.ideals.illinois.edu/oai-pmh?verb=GetRecord&metadataPrefix=etdms&identifier=oai%3Awww.ideals.illinois.edu%3A2142%2F129996