California Air Resources Board

Is smoke from a prescribed fire harmful to my health?

Prescribed fires are carried out during carefully selected weather conditions to ensure adequate smoke dispersion and to minimize air‑quality impacts. Although smoke can still irritate your eyes, nose, throat, and lungs, you can stay safe and healthy by taking simple steps, such as checking the Air Quality Index in the California Smoke Spotter App or monitoring the AirNow Fire & Smoke Map, staying indoors, using air filtration, and wearing an N95 mask if you need to go outside. 

Healthy adults are usually at low risk. People with heart or lung disease, older adults, and children are more sensitive to smoke, but they can also stay protected by taking extra precautions—such as spending time in a Clean Air Center during the burn.

People who exercise outdoors are also at risk because they breathe harder during physical activity, increasing their exposure to smoke. They should consider reducing the intensity or duration of outdoor exercise when smoke is present, even when the Air Quality Index is in the moderate range.

How does smoke from prescribed fires affect air quality?

Although prescribed fires are shorter in duration and intensity than wildfires fires, the smoke they produce can temporarily reduce air quality, especially near the burn. To protect public health, burners and air regulators work together to choose weather conditions that help smoke disperse quickly and keep impacts as low as possible while the prescribed fire is taking place.

How is safety ensured during a prescribed fire?

Safety and public health are the highest priorities during a prescribed fire. Agencies follow strict burn plans and emergency procedures, use trained fire specialists, monitor weather closely, prepare containment lines to keep the fire within a safe boundary, and keep firefighting equipment on site. Before the burn begins, managers confirm that weather, vegetation moisture, wind, and air quality conditions meet all safety and smoke dispersion requirements. Crews can pause or stop the burn at any time if conditions change.

Can a prescribed fire get out of control?

It is rare for a prescribed fire to spread beyond the planned burn area because of the rigorous planning and safety protocols involved. Agencies reduce risk by using containment lines, monitoring weather forecasts, setting staffing and operational requirements, preparing contingency resources, and maintaining continuous oversight throughout the burn. If a prescribed fire does extend beyond the planned area, agencies have clear procedures in place to respond quickly and suppress it.

How is it decided when and where prescribed fires will take place?

Agencies choose burn timing and locations based on factors such as the need to reduce dry vegetation that could fuel a future wildfire and the need to keep land and wildlife healthy. They select the time of year when vegetation is likely to burn safely, helping keep the fire manageable.

Before starting a burn, they also consider weather patterns, terrain, places where smoke could affect people’s health or visibility—such as schools, hospitals, or busy roads—expected air quality impacts, available crews, and potential effects on nearby communities.

Are prescribed fires safe for pets and livestock?

Prescribed fires are conducted with strict safety protocols to ensure nearby communities remain safe, including pets and livestock. While the fire itself is carefully contained, the primary impact on domestic animals comes from smoke and changes in air quality. During a burn, owners should provide animals with clean water, keep them sheltered when possible, and limit their exposure to smoke.

Sensitive animals may need to be monitored for signs of respiratory distress and relocated if necessary. If an animal shows respiratory issues, consult a veterinarian.

How do prescribed fires affect wildlife?

Prescribed fires generally benefit wildlife by improving habitat quality, encouraging fresh vegetation growth, and maintaining healthy ecosystems. Direct harm to wildlife is rare, and burns are commonly conducted outside primary nesting and mating seasons. When they occur, most animals temporarily move away from the area and return once conditions improve.

Many wildlife species benefit from healthier vegetation and greater habitat diversity after a burn, and many California ecosystems depend on periodic fire to remain healthy.