10th International Aerosol Conference September 2 - September 7, 2018 America's Center Convention Complex St. Louis, Missouri, USA
Abstract View
Long-term Performance Evaluation of Commercial Low-Cost PM2.5 Sensors in Houston, Texas
H. LANGLEY DEWITT, Bradley Flowers, Will Ollison, Walt Crow, American Petroleum Institute
Abstract Number: 610 Working Group: Instrumentation
Abstract Advances in air pollution monitoring technologies have enabled the development and proliferation of low-cost and portable air pollution sensors, which can monitor a variety of gas-phase and particulate matter (PM) species. Because of their lower cost, these air quality sensors are more accessible to researchers and the public, enabling collection of air quality data at significantly higher spatial and temporal resolution. As the use of low-cost air quality sensors has increased in recent years, laboratory and field performance evaluations have increasingly been conducted to quantify the quality of data obtained in comparison to EPA federal reference methods and research grade instrumentation. However, many of these sensor evaluations have been short-term; ranging from one week to several months in duration. There remains a need to demonstrate the quality of low-cost sensor data over much longer time periods, which would be more representative of standard usage.
This presentation will focus on the results of a 10-month study conducted by the American Petroleum Institute (API) to examine the long-term performance attributes of two low-cost optical particle counters, a Dylos Model DC1100 and an AirBeam. Field-testing was performed continuously from March 1, 2017 through December 31, 2017 in Houston, TX at an ambient air monitoring station operated by the Houston Regional Monitoring (HRM) network. This site was chosen due to its proximity to the Houston Industrial Complex and the complex nature of emissions sources in Houston. The site experiences wide ranges of temperature and humidity to further evaluate sensor performance under different meteorological parameters. Factory installed and post measurement algorithms for converting optical particle counts to PM2.5 mass concentrations were tested. The results from the low-cost PM2.5 sensors are directly compared with paired continuously operating Met One Model 1020 PM2.5 Beta Attenuation Federal Equivalent Method (FEM) Monitors and a Met One Super SASS PM2.5 chemical speciation sampler. The results from this study highlight the importance of post-processing on the fidelity of low-cost PM2.5 sensor data and potential issues with longer-term deployments, which to our knowledge have not been addressed with previous field campaigns.