Protecting Yourself from Wildfire Smoke
California is facing increasingly catastrophic wildfire seasons. Wildfire smoke – a complex mixture of air pollutants – is unhealthy to breathe and can be especially dangerous for children, the elderly, pregnant women and people with heart or respiratory conditions. These sensitive groups are advised to limit outdoor activities, especially when the Air Quality Index (AQI) reaches levels considered ‘Unhealthy for Sensitive Groups’ or above. Air quality has regularly been reaching ‘Unhealthy,’ ‘Very Unhealthy’ and even ‘Hazardous’ levels this wildfire season. Even healthy people may experience symptoms in smoky conditions or after exposure. Pets also can be affected by unhealthy air and should be brought indoors, if possible.
Be Ready for Wildfires
California has experienced some of the most destructive wildfire seasons in recent years. There are several steps you can take to keep your family safe before and during wildfire season.
Air Quality Guide for Particle Pollution
- For near real-time updates on air quality and smoke near you, visit the AirNow Fire and Smoke Map or the U.S. Forest Service Wildland Fire Air Quality Response Program
- For mobile devices, access air quality information for more than 150 California locations using BreatheWell
- Check with your local air district for the latest information specific to your community
Wildfires produce a range of harmful air pollutants, from known cancer-causing substances to tiny particles that can aggravate existing health problems and increase the risk of heart attack or stroke. Particulate matter (PM) is the principal pollutant of concern from wildfire smoke for the relatively short-term exposures (hours to weeks) typically experienced by the public. Particles from smoke tend to be very small (with diameters of 2.5 micrometers and smaller). They are small enough to get deep into the lungs and the tiniest, ultrafine particles can pass directly into the bloodstream. The association between PM2.5 and heart and lung health effects is well documented in scientific literature.
Larger and more frequent and intense wildfires are a growing public health problem, contributing to reduced air quality for people living near or downwind of fire. Health problems related to wildfire smoke exposure can be as mild as eye and respiratory tract irritation and as serious as worsening of heart and lung disease, including asthma, and even premature death.
While cloth face coverings offer protection against COVID-19 virus spread, they do not provide protection against smoke particles. People who must be outdoors for long periods, in areas with heavy smoke, or where ash is disturbed, may want to wear an N95 respirator mask. Those with existing respiratory, lung or heart conditions should limit their exposure by staying indoors. Since wearing a respirator can make it harder to breathe, those with lung or heart conditions should check with their doctor before using one.
Due to COVID-19, N95 masks may not be available.
Protecting Yourself from Smoke
Stay Indoors and Keep Indoor Air Clean
The best way to prevent breathing harmful particles in wildfire smoke is to stay indoors.
- When air quality reaches dangerous levels due to wildfire smoke, the most effective way to reduce exposure and avoid the ill effects of smoke is to stay indoors with windows and doors closed.
- If you have a central ducted air conditioning and heating system, be sure to set the system to “on” to ensure air is being filtered constantly, rather than “auto,” which runs the system intermittently.
- If your system brings fresh air into the home, close the fresh-air intake so that it operates in in recirculation mode to prevent outdoor smoke from getting inside.
- Install a high-efficiency filter (MERV 13 rating or higher) with a MERV rating as high as your system can handle, based on the manufacturer’s recommendation.
- Consider using a CARB-certified air cleaner which can greatly reduce indoor particle levels to further reduce impacts from smoke.
- Do not run swamp coolers or whole house fans.
- Avoid activities that increase indoor pollution, such as burning candles, using gas stoves and vacuuming.
Avoid outdoor activities
- People should avoid exercising outdoors during smoky conditions. Exposure and the resulting health effects depend on the amount of time spent outside, level of exertion, level of air pollution, and possible existing health conditions.
- Consider eliminating outdoor activities altogether when the AQI reaches unhealthy levels.
- Officials may call for an evacuation in emergency situations or when the AQI reaches the hazardous level. Always follow evacuation orders. In the event of an evacuation, make sure to operate your vehicle with the windows rolled up and the air conditioner set to recirculate.
Interviews with CARB experts on the following topics are available for attribution, use and download.
- Wildfire Smoke Health Risks
- Protecting Yourself from Wildfire Smoke
- Accessing Local Air Quality Information
- Air Quality Index
- Air Pollution Monitoring
To request graphics for download contact CARB's Office of Communications at (916) 322-2990.
- CAL FIRE: Ready for Wildfire
- CalEPA: Fire Response and Recovery
- Cal/OSHA: Worker Safety and Health in Wildfire Regions
- CDPH: Wildfires
- California Smoke Blog
- U.S. EPA: Wildfire Smoke Guide for Public Officials
- U.S. EPA: Smoke Ready Toolbox
- U.S.F.S. Wildland Fire Air Quality Response Program: Smoke Forecast Outlooks
- CDC: Wildfire Smoke and COVID-19