The moment a wildfire starts near you, you'll get an instant alert and simple tips to reduce your smoke exposure.
30xSmaller than a human hair
Fine enough to reach deep into the lungs. A MERV 13 is built to capture it.
It Doesn't Stay Local
Smoke rides the wind far downwind — you can get smoky air with no fire nearby.
Simple steps to reduce indoor exposure.
During smoke events, the EPA recommends upgrading to a MERV 13 filter — or the highest-rated filter your system can handle — to help reduce the fine particles smoke brings indoors. MERV 13 is the level most home HVAC systems can run while still capturing PM2.5, the fine particulate that makes up the bulk of wildfire smoke.
Over 70,000 wildfires burn in the U.S. every year.
Wildfire smoke can travel 1,000+ miles, affecting states that aren't even near the blaze.
Exposure to wildfire smoke can worsen asthma, trigger heart issues, and lead to ER visits.
Indoor air can hold more fine particles during wildfire events unless it's properly filtered.
The EPA advises using MERV 13 filters or portable HEPA air cleaners during wildfire smoke events.
Use the live wildfire smoke tracker and upgrade your air filters today to protect your lungs and your home.
Shop Filters For Smoke Protection
Real-Time Air Quality Guide and Tips
Los Angeles covers beaches, basins, and canyons. Smoke can sit in one neighborhood and clear in the next. In this blog, you will learn how to check today’s live conditions, which LA patterns matter, and how to set a simple plan for your home, building, and commute.
Check the AirNow Fire and Smoke Map in the morning and again after winds shift.
During smoke, close windows, set HVAC to recirculate, and use the highest MERV your system can handle while keeping normal airflow. Add a HEPA purifier.
A two inch or four inch pleated filter often lasts longer than a one inch filter.
Limit outdoor exertion at AQI 101+. If you must be outside in heavy smoke, use a well fitting N95 or P100.
After conditions improve, replace smoke-loaded filters and wipe hard surfaces.
Open the AirNow Fire and Smoke Map. Enter your ZIP code. Tap nearby monitors to see AQI and PM2.5. Use the time slider to check expected changes. Recheck mid to late afternoon when sea breezes or canyon winds can move smoke.
Santa Ana and canyon winds. Offshore flow can push smoke quickly through passes into valley areas.
Marine layer and sea breeze. Coastal areas may clear before inland valleys. Confirm AQI locally before opening windows.
Basin inversions. Overnight inversions can hold smoke near the ground. Air often improves by late morning as mixing increases.
Set HVAC to recirculate and let the fan run so air passes the filter more often. During smoke, install MERV 13 only if airflow and comfort stay normal.
Create one clean air room with a right sized HEPA purifier. Keep the door closed and block the gap at the threshold. Ventilate briefly only after the map shows cleaner air.
Close windows and exterior doors. Seal obvious gaps with painter’s tape as a temporary fix.
Minimize exhaust that pulls outside air. Limit bath and kitchen fans during smoky hours.
Reduce indoor particle sources. Skip frying, candles, incense, and fireplaces.
Keep humidity near 30 to 50 percent to prevent condensation and musty odors.
Inspect the filter weekly during prolonged smoke. Replace early if it looks gray or matted or if airflow drops.
If you cool with a window, wall, or portable unit, set it to recirculate and seal gaps around the unit. Run a HEPA purifier in the same room. Ventilate briefly only after the map shows cleaner air for several hours.
Keep common area doors and windows closed. Run central fans on recirculate. Place HEPA purifiers in gyms, lounges, and mail rooms. Post the day’s AQI in the lobby and schedule maintenance for the cleanest hours shown on the map.
Post the current AQI at the entrance. When levels rise, reduce strenuous activities, keep doors closed, and run HVAC continuously on recirculate with the highest MERV the system supports. Use HEPA purifiers in classrooms, studios, and meeting spaces.
Keep windows closed and set the vehicle to recirculate. Make sure a cabin air filter is installed and in good condition. Plan fuel and rest stops for areas the map shows as cleaner. Avoid long idling when AQI is high.
Check monthly by default. During prolonged smoke, inspect every one to two weeks. Replace early if the media looks gray or matted or if airflow drops at vents. If your cabinet allows it, a two-inch or four-inch pleated filter provides more media and often lasts longer than a one inch filter. Return to your normal schedule after several clear days.
Replace smoke-loaded filters. Vacuum with a HEPA vacuum. Wipe hard surfaces with a damp cloth. Clean supply and return grilles. Confirm the HVAC drain pan is clean and draining.
Use MERV 13 during smoke if your system keeps normal airflow. Order exact-fit pleated filters in standard or custom sizes from Filterbuy. Filters are made in the USA and ship fast with free delivery. Turn on Auto Delivery so replacements arrive on schedule through LA’s smoke season.
Open the AirNow Fire and Smoke Map and search your ZIP code. Tap nearby monitors to see AQI, PM2.5, and health guidance.
Use AQI 101 or higher as your cue to limit outdoor activity and improve indoor filtration. Sensitive groups should be cautious even at Moderate.
Check the map first. Coastal areas can clear before valleys, but conditions often flip later in the day. Ventilate briefly only after AQI has improved for several hours.
Many homes run MERV 11 daily. Move to MERV 13 during smoke if your system keeps normal airflow and comfort. If airflow drops or noise rises, step back to MERV 11 and add a HEPA purifier.
Yes during smoke. Set the system to recirculate so indoor air passes the filter more often.
Set it to recirculate and seal gaps around the unit. Run a HEPA purifier in the same room. Ventilate briefly only when AQI improves.
Choose one bedroom or living area. Keep doors and windows closed. Run a HEPA purifier sized for the room. Block the door gap with a draft stopper or rolled towel.
Check monthly by default. During prolonged smoke, inspect every one to two weeks and replace early if the media looks gray or matted or if airflow drops. Two inch or four inch pleated filters often last longer than one inch.
They can help short term if built safely with a newer certified box fan and a MERV 13 filter. Do not leave them unattended.
A well fitting N95 or P100 respirator can reduce particle exposure. Cloth and surgical masks are not designed for fine smoke.
Keep common doors and windows closed, run central fans on recirculate, post the day’s AQI, and use HEPA purifiers in gyms, lounges, and mail rooms.
Post the current AQI, keep doors closed at elevated levels, reduce strenuous activities, run HVAC continuously on recirculate with the highest MERV the system supports, and add HEPA units in classrooms and meeting spaces.
Keep windows closed, set the vehicle to recirculate, and confirm a cabin air filter is installed and in good condition. Plan stops for areas the map shows as cleaner and avoid long idling when AQI is high.
