Impact of 4th of July Fireworks on Spatiotemporal PM Concentrations in California Based on the PurpleAir Sensor Network: Implications for Policy and Environmental Justice.

Fireworks are often used in celebration, causing short term, extremely high particulate matter air pollution. In recent years, the rapid development and expansion of low-cost air quality sensors by companies such as PurpleAir has enabled an understanding of air pollution at a much higher spatiotemporal resolution compared to traditional monitoring networks. In this study, real-time PM measurements from 751 PurpleAir sensors operating from June to July in 2019 and 2020 were used to examine the impact of 4th of July fireworks on hourly and daily PM concentrations at the census tract and county levels in California.