Wildfire smoke

What it is

Wildfire smoke is a mix of gases and fine particles from burning plants and buildings. It can travel hundreds of miles, so you can breathe unhealthy air even when the fire is far away.

Who is at risk

Everyone can be affected, but the risk is highest for children, older adults, pregnant people, outdoor workers, and anyone with asthma, lung disease or heart disease.

Get ready now

1. Learn how to check the Air Quality Index for your area at AirNow.gov.
2. Buy N95 or P100 masks that fit each adult in your home. Cloth and surgical masks do not stop smoke particles.
3. Get a portable air cleaner with a HEPA filter for one room, or learn how to make a box-fan filter.
4. If you have central air, ask about the highest-rated filter your system can take (MERV 13 or higher if possible).
5. Choose a clean room in your home with as few windows and doors as possible.
6. If someone in your home has asthma or heart or lung disease, ask their doctor for a plan for smoky days and keep extra medicine.

When it happens

1. Stay indoors with windows and doors closed when the air is unhealthy.
2. Run your air cleaner in your clean room and set air conditioning to recirculate.
3. Avoid things that add to indoor pollution: candles, frying, smoking and vacuuming.
4. Wear a well-fitting N95 or P100 mask if you must go outside.
5. If it gets too hot to stay inside with windows closed, go somewhere with cleaner, cooler air.
6. Get medical help for trouble breathing, chest pain or a fast heartbeat.

After

1. Keep checking air quality; smoke can come back when the wind changes.
2. Replace air filters that are dirty or grey.
3. Air out your home once outdoor air is clean.
4. Wear a mask and gloves when cleaning ash, and dampen it first instead of sweeping it dry.

Official sources

• AirNow.gov: Air quality and smoke
• Ready.gov: Wildfires
• CDC: Wildfire smoke
• National Weather Service: Wildfire safety

This guide summarises public advice. Always follow instructions from local officials and emergency services.