Spatial and Temporal Trends of Air Pollutants in the South Coast Basin Using Low Cost Sensors

Summary

The emergence of small, portable, low-cost air sensors has encouraged a shift toward their use and away from traditional approaches to monitoring air quality. The U.S. Environmental Protection Agency (U.S. EPA), in collaboration with South Coast AQMD's AQ-SPEC, deployed custom-built sensor devices (pods) measuring fine particulate matter (PM_2.5), ozone (O₃), relative humidity, and temperature at nine locations throughout southern California from January 2017 to April 2017 to evaluate their performance under "real-life" conditions. Prior to the deployment, these pods were evaluated within the AQ-SPEC program both in the field and in the laboratory. Southern California is an ideal testing location for air quality sensor technology, as it often experiences elevated air pollutant levels resulting from gasoline and diesel engines, marine ports, and various other industries. The South Coast Air Basin’s particular meteorology (frequent sunny days and little precipitation) and geography also contribute to the elevated pollution levels in the region. The goal of this project was to characterize the performance of these newly developed pods and better understand their potential applications for community monitoring. The report herein, summarizes the AQ-SPEC field and laboratory performance evaluations of the Citizen Science Air Monitor (CSAM) sensor pods designed and developed by the EPA. In addition, this document summarizes the spatial and temporal variability of the PM_2.5 and O₃ measurements collected during the field deployment of the CSAM pods at nine monitoring locations covering approximately a 200 km² area in southern California.

South Coast AQMD CSAM Report to EPA

Authors: ¹Feenstra B., ¹Papapostolou V. and ¹Zhang H.
Reviewers: ¹Polidori A., ²Vallano D., ²Duvall R. and ²Williams R.

¹South Coast Air Quality Management District / Air Quality Sensor Performance Evaluation Center (AQ-SPEC)
²U.S. Environmental Protection Agency