Assessing Indoor Air Quality in Educational Buildings Using a Low-Cost Sensor Network

JIANING BAO, Nigel Kaye, Ehsan Mousavi, Christopher Post, Vincent Blouin, Andrew Metcalf, Clemson University

     Abstract Number: 395
     Working Group: Aerosol Science of Infectious Diseases: What We Have Learned and Still Need to Know about Transmission, Prevention, and the One Health Concept

Abstract
The current COVID-19 crisis highlights the need for safer building environments regarding indoor air quality, especially for high-occupancy indoor environments including schools and colleges. Low-cost indoor air quality sensor technology provides the opportunities to measure indoor pollutant concentrations with high temporal and spatial resolution by deploying multiple sensors in indoor spaces horizontally and vertically. The objective of this study is to use a low-cost sensor network to evaluate indoor air quality by measuring the concentrations of particulate matter (PM), carbon dioxide (CO2), total volatile organic compounds (TVOC), temperature, and relative humidity (RH) at multiple locations in a classroom. We conducted experiments with point sources of PM and CO2 into the indoor space. By analyzing the decay of PM and CO2 concentrations with time, we evaluate the effectiveness of the ventilation and filtration system in the classroom. The low-cost sensor network also measures the spatial variability of pollutant concentrations, including horizontal spreading and vertical stratification, which shows the spatial evolution of pollution distribution from point sources. Finally, we evaluate the performance of various indoor air pollution mitigation techniques, including HEPA filters and low-cost, do-it-yourself filtered box fans.