Air Quality Monitoring and the Safety of Farmworkers in Wildfire Mandatory Evacuation Zones

The increasing frequency and severity of wildfires due to climate change pose health risks to migrant farm workers laboring in wildfire-prone regions. This study focuses on Sonoma County, California, investigating the effectiveness of air monitoring and safety protections for farmworkers. The analysis employs AirNow and PurpleAir PM_2.5 data acquired during the 2020 wildfire season, comparing spatial variability in air pollution. Results show significant differences between the single Sonoma County AirNow station data and the PurpleAir data in the regions directly impacted by wildfire smoke. Three distinct wildfire pollution episodes with elevated PM_2.5 levels are identified to examine the regional variations. This study also examines the system used to exempt farmworkers from wildfire mandatory evacuation orders, finding incomplete information, ad hoc decision-making, and scant enforcement. In response, we make policy recommendations that include stricter requirements for employers, real-time air quality monitoring, post-exposure health screenings, and hazard pay. Our findings underscore the need for significant consideration of localized air quality readings and the importance of equitable disaster policies for protecting the health of farmworkers (particularly those who are undocumented migrants) in the face of escalating wildfire risks.

Key Points

• The Agricultural Pass program challenges the safety of migrant farmworkers during extreme wildfires
• Regional variabilities in air quality emphasize the importance of localized measurements
• The use of local low-cost sensor data with recommended filtering and smoke correction, enhances health and safety air quality monitoring

Plain Language Summary

In Sonoma County, California, wildfires and wildfire smoke are becoming more frequent and severe due to climate change. This study looks at how wildfire smoke could impact farmworkers, who often work outdoors. By comparing data from different air quality monitors during the 2020 Sonoma County wildfires, we found that farmworkers are exposed to high pollution levels, with some monitors showing more pollution than others. We also found that the system for deciding when farmworkers should labor during wildfires needs to be more consistent and adequately protect their health. Based on our findings, we recommend better air quality monitoring, improved policies to protect farmworkers during wildfires, and more support for those affected by the pollution. This research highlights the need to prioritize the health and safety of farmworkers, especially as wildfires become more common.