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Prescribed Burning FAQs
Frequently asked questions about prescribed burns.
What is a prescribed burn?
A prescribed burn is a controlled, low intensity fire conducted under approved plans and defined conditions by trained land and fire managers to reduce vegetation and fuels that can contribute to wildfires. Prescribed burns are sometimes called prescribed fires or controlled burns.
What are prescribed burns for?
Many ecosystems evolved with recurring fire, and vegetation naturally builds up over time in areas where fire has not occurred in a long time. Prescribed burns reduce hazardous fuels, restore ecological processes, and reduce the potential intensity of future wildfires. Over time, proactively reducing fuels can help reduce the frequency and the intensity of wildfires, and in turn, reduce air quality impacts from smoke overall.
Why not just remove vegetation mechanically?
Mechanical methods such as mowing, thinning, grazing, and chipping are important land management tools and are often used before a prescribed burn. However, these methods may not be practical on steep or remote terrain and do not fully replicate the fire prevention and ecological effects that a prescribed burn can achieve.
What roles do the Air District, fire agencies, and burn operators play?
The Air District is responsible for reviewing and approving smoke management plans, monitoring weather and air quality conditions, and burn-day authorization. CAL FIRE and local fire agencies address fire safety and issue applicable permits. The land manager or burn operator is responsible for conducting a prescribed burn under the approved plans and permits.
Does the Air District conduct prescribed burns?
No. The Air District reviews and approves smoke management plans, monitors weather and air quality conditions, and issues burn authorizations, but it does not plan or ignite burns. Prescribed burns are conducted by land managers or fire agencies, who are responsible for planning, staffing, and carrying out a burn under their approved plan and permits.
How does the Air District decide whether a prescribed burn may proceed?
The Air District uses a multi-layered review and approval process to keep prescribed burning both possible and responsive to air quality conditions. At least 30 days before a planned burn, burn operators must submit a Smoke Management Plan to the Air District for review and approval. Closer to the planned date of the burn, the Air District evaluates forecasted weather, air quality, and other relevant conditions and coordinates daily with the burn operator and other partner agencies on whether a burn can proceed (see How Prescribed Burns Are Reviewed and Authorized).
Can the forecasted weather and air quality conditions be wrong?
Air District meteorologists closely evaluate weather and air quality forecasts ahead of a prescribed burn, but local conditions can sometimes be different than expected. The Bay Area’s varied microclimates mean that weather conditions can shift quickly and vary considerably over short distances. This uncertainty is part of why agencies continue monitoring conditions and stay in close coordination throughout a burn.
Can a burn be stopped if smoke affects a community?
Burn operators can slow or stop additional ignition and take other actions if conditions become unfavorable. However, once going, fire cannot always be extinguished immediately without creating safety concerns or generating additional smoke, and fuels may continue to smolder and generate smoke after active flames have stopped.
Why can smoke appear hours after ignition?
Smoke can linger above or near the burn, settle near the ground, or be carried toward a community as winds shift, depending on weather conditions. Smoldering vegetation can also keep producing smoke well after active flames have died down.
How will I know if a prescribed burn is planned near me?
Check the Air District’s Current and Planned Prescribed Burns page, along with announcements from the land manager, local fire agency, county, and municipal alert systems. Because final authorization depends on weather, air quality, and other conditions, planned dates may change with limited notice.
What should I do if smoke reaches my neighborhood?
Check current air quality, reduce outdoor activity, close windows and doors, use effective indoor filtration if available, set your vehicle’s ventilation setting to recirculate to not bring in outside air, and follow health guidance. People with heart or lung conditions should follow their healthcare provider’s recommendations. Seek urgent medical care for severe symptoms (see Prescribed Burning, Smoke, and Health).
Is smoke from prescribed burns harmful?
Prescribed burns produce smoke containing fine particles and other pollutants that can irritate the eyes and respiratory system and worsen heart and lung conditions, among other health impacts. Although burns are carefully planned and controlled to limit impacts on surrounding communities, smoke from an authorized prescribed burn may still temporarily impact nearby communities. People should take steps to protect their health when smoke is present (see Prescribed Burning, Smoke, and Health).
What air pollutants are found in smoke?
Smoke from wildland fires contains several pollutants. A pollutant of specific concern is PM2.5, which refers to particulate matter with particle diameters of 2.5 micrometers or smaller. When inhaled, PM2.5 can travel deep into the lungs and even the bloodstream. Smoke contains a range of other harmful pollutants, including gases such as carbon monoxide and nitrogen oxides and carcinogens such as benzene and formaldehyde.
If smoke from prescribed burns can affect air quality in nearby communities, why are they allowed at all?
Prescribed burns are permitted because the alternative – allowing vegetation to accumulate – tends to produce worse outcomes over time. Unmanaged vegetation can fuel large, high-intensity wildfires that generate far more smoke than a prescribed burn would and can persist for days and weeks at a time.
How does prescribed burn smoke compare with wildfire smoke?
Smoke from any fire contains fine particles and other pollutants that cause health impacts. However, prescribed burns are planned, limited in size and duration, and conducted under certain weather, air quality, and fuel conditions to limit smoke impact in nearby communities. Large wildfires can burn with much greater intensity and produce widespread, harmful smoke for days or weeks.
What is the best place to find current air quality conditions?
You can check current air quality conditions via the AirNow Fire and Smoke Map or the Air District’s Current Air Quality Conditions webpage, among other sources. The Fire and Smoke Map specifically shows data for PM2.5 from regulatory air monitors, such as those operated by the Air District, and publicly available air sensors. The Air District has several fact sheets on air monitoring data and data sources, including:
- Real-Time Air Quality Data Sources in the Bay Area to learn more about different online sources for real-time air quality data and interpreting the Air Quality Index
- Understanding Air Quality Data Sources
to read about strengths and limitations of different online sources of air quality data - Types of Particulate Matter Monitoring for information on regulatory monitors vs. air sensors
- Why Air Quality Maps May Look Different for information on why air quality data may appear different depending on what website you are using
Last Updated: 15/10/2026