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Installing an air conditioner

How to keep indoor air clean on smoky days

Protect your health on smoky days:

Air quality conditions may change quickly. Go to Puget Sound Clean Air Agency’s website or follow them on Twitter for the current smoke level report for King County.

Keep out of the smoke as much as possible and keep the air indoors as unpolluted as possible (see "Keep indoor air clean" below).
Limit vigorous physical activity when the air quality is poor. This includes running, biking, physical labor, and sports.
  • Close windows and doors as much as possible.

  • Use an air cleaner with a HEPA filter if possible.

  • Use fans or an air conditioner (AC) when it's hot, if possible. Set your AC to recirculate.

  • If you aren't able to leave and it's too hot, it's better to open the windows for a short time to cool the indoor space than to overheat.

  • A DIY air filter fan may be an easy and cost-effective way to clean air inside your home. Information on how to construct an air filter fan and important safety tips are on Puget Sound Clean Air Agency's DIY Air Filter website.
  • Don't pollute the indoor air. Don't smoke, use candles, or vacuum. Avoid frying and broiling when cooking indoors.

Call 9-1-1 if you or someone else has serious symptoms, like trouble breathing. You can also send a text to 9-1-1 if you are Deaf, hard of hearing, speech impaired, and anyone who might be unsafe if they were to be heard by an intruder or abusive partner. Learn more about text-to-911.

Prepare for wildfire smoke season:

  • Wildfire smoke preparedness during COVID-19 pandemic

  • Plan how you will keep indoor air clear on smoky days. Learn how to make a “clean air room” in your home so that you have place to get away from the smoke, even if you need to occasionally open your windows: How to keep indoor air clean on smoky days, Public Health Insider

  • Consider getting an air purifier. Air purifiers with a high-efficiency particulate air (HEPA) filter will reduce the number of irritating fine particles in indoor air. A HEPA filter with charcoal will help remove some of the gases from the smoke. Do not use an air purifier that produces ozone. More information: EPA's Indoor Air Filtration Factsheet (PDF)

  • Make an air filter fan. Learn how on Puget Sound Clean Air Agency's DIY Air Filter website or this quick version with a box fan, a MERV-13 filter, and duct tape: Public Health Crafter's Corner: 1-minute DIY Filter Fan, Public Health Insider

  • If you have asthma or another respiratory condition, make sure you have an inhaler or other medications that you might need. Make an asthma management plan with your healthcare provider.

  • Make plans for indoor activities for kids on smoky days. Consider what your children can do if they need to stay indoors when smoke levels are "unhealthy for sensitive groups" or worse.

  • Schools, camps, sports teams, and daycare providers should make plans for smoky days. Plan to postpone outdoor activities or move them indoors when smoke levels are "unhealthy for sensitive groups" or worse. Air Pollution and School Activity Guide.

Masks and wildfire smoke:

The right mask and proper fit can reduce your exposure to wildfire smoke, but they don't work for everyone. This info is also available in PDF format.

Face coverings protect against COVID-19 but cloth masks don't provide much protection from wildfire smoke. N95 respirators and KN95 masks offer good protection. If you have a pre-existing condition that might make you more sensitive to smoke, consult your medical provider.