What a Burn Day Actually Is
A Permissive Burn Day (sometimes called simply a "burn day") is a daily determination made by an Air Quality Management District (AQMD) or Air Pollution Control District (APCD) that meteorological conditions that day are favorable enough to allow open burning without causing unacceptable air quality impacts.
The designation is made based on weather forecasts: wind speed and direction, mixing height (how high smoke will rise before dispersing), temperature inversions, relative humidity, and existing air quality conditions. On days when the atmosphere will disperse smoke well, burning is permitted. On days when smoke would trap near the ground and accumulate — degrading air quality for surrounding communities — burning is prohibited.
Who Decides Burn Day Status
California has 35 Air Quality Management Districts and Air Pollution Control Districts — each sets its own daily burn day status independently. Most states with air-quality-based burning restrictions operate similarly: regional air quality agencies make independent daily determinations based on local meteorology.
The key agencies by region:
- California (SoCal): South Coast AQMD — aqmd.gov
- California (Bay Area): Bay Area AQMD — baaqmd.gov (publishes Spare the Air alerts)
- California (Central Valley): San Joaquin Valley APCD — valleyair.org
- Oregon: Oregon DEQ — works with local air quality authorities
- Washington: Puget Sound Clean Air Agency — pscleanair.org
- Washington (eastern): Yakima Regional Clean Air Agency, Spokane Regional Clean Air Agency
How to Check Today's Burn Day Status
- Identify your Air Quality District — search your city/county + "air quality management district" to find the right agency.
- Visit the district's website — burn day status is typically on the home page or a dedicated "open burning" section.
- Check by 7 AM on the burn day — most districts post the next day's status by 4 PM the prior day, but confirm on the morning of your planned burn.
- Sign up for alerts — many districts offer email or text notifications for burn day status. This is the most reliable way to stay current.
- When in doubt, call — district hotlines answer burn day questions directly.
Types of Burn Day Designations
Terminology varies by district, but common designations include:
- Permissive Burn Day: Open burning authorized (with valid permit)
- No Burn Day: Open burning prohibited regardless of permit status
- Spare the Air Day (Bay Area): No wood burning of any kind — affects both outdoor burning and wood-burning fireplaces
- Wood Burning Curtailment: Some districts restrict indoor wood burning (fireplaces, stoves) separately from outdoor burning
- Burn Ban: Forestry-issued restriction during high fire danger — separate from air quality designations
What If Conditions Change After You Start Burning
If you started a permitted burn on a Permissive Burn Day and conditions deteriorate — wind picks up, air quality worsens, a No Burn order is issued mid-day — you are legally required to extinguish immediately. A changing burn day status post-ignition is not a defense against a citation for continued burning during prohibited conditions.
Frequently Asked Questions
A Spare the Air day is the Bay Area AQMD's designation for high-pollution days when all wood burning — including indoor fireplaces — is prohibited. The name comes from the public campaign to encourage residents to 'spare the air' from additional wood smoke. Spare the Air days are announced the prior afternoon and are common November–February during weather inversions.
In most districts, burn day restrictions apply to open burning of vegetative debris, not to small recreational campfires. However, some districts (especially in California) restrict all outdoor burning including campfires on No Burn Days. Check your specific district's rules — they vary.
Relatively few. The San Joaquin Valley APCD issues Permissive Burn Day determinations, but the Valley's geography — mountains on all sides trap pollution — means air quality frequently cannot accommodate additional burning. During late fall and winter (temperature inversion season), burn days may be designated only a handful of times per month.