Wildfire Smoke and Ash

Wildfire smoke and ash are challenges to California's public health that have the potential to increase with continuing climate change. AQS staff are conducting ongoing investigations with other state, federal, and university partners to identify any unique chemical and physical exposures associated with wildfire events and minimize their impacts. 

Smoldering wildfires can emit particulate matter (PM) and gases that are similar to smoke from wood stoves or crop burning, but can also include emissions from man-made structures burned in the fire.  Community airborne smoke and ash exposures can vary with fire size, location, and local weather patterns. Potential methods to reduce one's exposure include air cleaners, masks, staying indoors, or leaving smoky areas of the state, depending on the severity of an episode and the air monitoring information available. 

More information on AQS studies, current smoke conditions, and general smoke guidance are available at the links below.

AQS smoke and ash studies:

• Filtration for Respiratory Exposure to Wildfire Smoke from Swamp Cooler Air (FRESSCA) (ongoing project with Public Health Institute, Illinois Institute of Technology, University of California - San Francisco , University of Colorado Boulder , and Central California Environmental Justice Network) - Link to US EPA funding project page
  
• Smoke-specific air tracers, heavy metals in smoke, furnace filter sampling, and electron microscopy of wildfire tar balls: "Composition of particulate matter during a wildfire smoke episode in an urban area" (Aerosol Science & Technology, 2021)
  
• Presentation on wildfire smoke chemistry and air cleaners: "Potential Health Impacts of Particles and Gases Emitted by Wildfires" (US EPA Clean Air Spaces web summit, 2019) (PDF)
  
• Air sampling to identify different PM types in urban areas, including wildfire smoke: "Field testing a low-cost passive aerosol sampler for long-term measurement of ambient PM2.5 concentrations and particle composition" (Atmospheric Environment, 2019)
  
• Electron microscopy of smoke from agricultural burns: "Measurement of ambient particulate matter concentrations and particle types near agricultural burns using electron microscopy and passive samplers" (Atmospheric Environment, 2012)
  
• Community air monitoring near agricultural burns: "Agricultural burning monitored for air pollutants in Imperial County; exposure reduction recommendations developed"(CA Agriculture, 2012)
  

External smoke and ash information pages:

• AirNow Fire & Smoke Map

• US EPA wildfires and IAQ resources

• CDPH Emergency Preparedness Office smoke guidance (PDF)
  

• US EPA smoke guidance (PDF)
  

• CDPH Emergency Preparedness Office wildfire resources
  

• CDPH Environmental Health Investigations Branch wildfire pages
  

• CARB Protecting yourself from Wildfire Smoke​