Smoke From Fires

Smoke from contains very small particles and gases. These particles can get into your eyes and lungs where they can cause health problems. The main sources of smoke from fires in Washington are:

  • Wildfires
  • Wood stoves, pellet stoves, and fireplaces
  • Agricultural burning
  • Prescribed fires (used to manage forests)

Wildfire smoke in particular is a growing health risk in Washington, especially during the summer and early fall. Exposure can lead to impacts from mild irritation to serious health problems.  Children, older adults, pregnant people, and those with respiratory or heart conditions are at a higher risk of health problems. This guidance will help you reduce exposure, monitor air quality, and protect your health indoors and outdoors. 

Frequently Asked Questions

What health problems can smoke cause?

Exposure to smoke from fires can cause or worsen several health problems that range from minor to severe. When smoke is present, the worst symptoms more often occur in people with pre-existing health conditions, though anyone can have symptoms or health problems. Some symptoms are:

  • Eye, nose, and throat irritation (burning eyes, runny nose and coughing)
  • Fatigue
  • Headache
  • Wheezing and shortness of breath
  • Increased symptoms from existing conditions, particularly lung and heart diseases(asthma attacks, chest pain, irregular heartbeat)
  • Mental health concerns and stress

Seek medical attention if you experience severe symptoms, such as chest pain or difficulty breathing, during wildfire smoke events and in the week after.

Who is especially sensitive to smoke?

Breathing in smoke is not good for anyone. Everyone should take steps to reduce exposure and watch for symptoms during and after smoke events. Most often when people are exposed to lower levels of smoke, they have minor symptoms like sore throats and headaches.

As the smoke levels increase the impacts can worsen and become severe, especially for sensitive groups. Many people are at increased risk of severe health impacts, including:

  • People with lung diseases, such as asthma or chronic obstructive pulmonary disease (COPD), chronic bronchitis, and emphysema.
  • People with current or recent respiratory infections, such as COVID-19, pneumonia, acute bronchitis, bronchiolitis, colds, or flu.
  • People with existing heart or circulatory problems, such as congestive heart failure or coronary artery disease.
  • People with a history of heart attack or stroke.
  • People with diabetes because they are more likely to have an undiagnosed cardiovascular disease.
  • People 18 years old and younger because their lungs and airways are still developing, and they breathe more air per pound of body weight than adults.
  • People 65 years old and older because they are more likely to have unrecognized heart or lung diseases.
  • Pregnant people because both the pregnant person and fetus are at increased risk of health effects.
  • People with access and functional needs who may need additional assistance due to any condition that may limit their ability to act in an emergency.
  • People who smoke or have a history of smoking because they are more likely to already have lower lung function and/or lung diseases.
  • People who work outdoors because they often spend more time outside and could mean they are exposed to smoke longer.
  • Communities of color because they have often experienced social and economic inequities which contribute to increased risk of negative health impacts from smoke.
  • Tribal members and Indigenous peoples because they are often impacted first and worst from climate change hazards, including smoke.
  • People with low income because they may be less likely to have access to health care or to be able to afford interventions to reduce exposure.
  • People who are unhoused or unsheltered because more time outside can increase exposure to smoke and they may not have access to social and health services.

Additional Tips

 Where can I check the current air quality?
  • Washington Smoke Blog Check current and forecasted wildfire and smoke locations. This is the one-stop-shop for all your information during wildfire smoke season (typically July or August-September but can begin as early as May and end as late as October).
  • Department of Ecology’s Washington Air Quality Map webpage – Year-round current and forecasted air quality information.
  • Washington Air Quality Guide for Particle Pollution (PDF) - This graphic provides health recommendations based on EPA's Air Quality Index (AQI).
  • Local air quality reports and news stations – Your local clean air agency and/or news organization may also have resources available  to help you stay informed.
  • Use these mobile apps to check air quality anytime, anywhere:
    • Air Quality Washington – This app uses information from Ecology’s Washington Air Quality Network. The Washington Air Quality Network website also offers a web app download.
What can I do to protect myself and my family from smoke?
  • Stay updated on current and forecasted air quality. See “Where can I check the current air quality?" for more resources.
  • When outdoors, limit the amount of time and intensity of physical activity. See “Should I exercise when it's smoky?”.
  • Stay indoors and take actions to keep indoor air clean
    • Close windows and doors, unless it is too hot to maintain safe temperatures. See “What if I don’t have air conditioning and it’s hot indoors?”.
    • Filter air through an HVAC system, a HEPA portable air cleaner, or DIY box fan filter. See “How can I improve filtration in my home to reduce smoke levels?”.
    • Set HVAC to recirculate mode or close the outdoor/fresh air intake.
    • Don’t add to indoor pollution. This is always good practice, but especially when it’s smoky.
      • Avoid burning candles, incense, and wood in fireplaces.
      • Avoid using sprays, diffused essential oils, or air fresheners.
      • Avoid broiling or frying food and limit use of gas or propane stoves or ovens.
      • Avoid using gas or propane furnaces or heaters.
      • Avoid smoking or vaping indoors.
      • Avoid sweeping or vacuuming unless your vacuum has a HEPA filter.
    • Create a cleaner air room in your home that is set up to keep levels of smoke lower during a wildfire smoke event. Watch a video and learn how to create a clean room, EPA.

      . 

  • During long-term (3-4 days or more) smoke events, take advantage of periods of improved air quality, such as during rain or shifts in wind, to open windows and set your HVAC system to intake fresh air.
  • If cleaner air at home cannot be maintained, go elsewhere, such as a family or friend’s place, an indoor public space, or an unimpacted area.
  • If you must be outside for a limited duration, consider wearing a properly fitted NIOSH-approved particulate respirator, such as an N95 mask.(See “Should I use a respirator when there is outdoor smoke?”).
  • If you have asthma or other lung diseases, follow your health care provider’s advice or asthma action plan, if you have one.
What if it's hot indoors and I don't have air conditioning?

It can be a challenge to keep smoke out when it’s hot, especially without an air conditioner or central cooling system. Pay attention to rising temperatures, as heat-related illness can occur quickly and can be life threatening. If it's hot indoors during poor air quality, these steps can help you stay cool:

  • Close windows, curtains, and shades during the day and use portable fans.
  • Minimize your use of the stove and oven during the hottest parts of the day.
  • Take a cool bath or shower. Be mindful of extreme temperature changes, which can cause life-threatening issues.
  • Use ice packs or put your feet in cool water. Apply wet rags on the back of your neck or mist yourself with water while sitting near a fan.
  • Stay hydrated, especially with water. Avoid sugary or alcoholic drinks since these can be dehydrating.
  • Go to a cooler indoor place – even if only for a few hours. For updated information on cooling centers in your community, visit Washington 2-1-1.
  • Track the air quality (See “Where can I check the current air quality?") and open your windows when the air quality improves.
  • Only open windows when it is cooler outside than inside. An open window is most effective when a door or additional window can be opened to provide a cross draft. For more information, see Cooling Indoor Spaces Without Air Conditioning (PDF). 
  • Take steps to filter indoor air (See “How can I improve filtration in my home to reduce smoke levels?”).
  • To check your area's current and forecasted heat risk and find suggestion precautions, see CDC's HeatRisk. 

For information about preventing heat-related illness, follow DOH's hot weather safety guidance or CDC's Preventing Heat-Related Illness.

Should I use a mask when there is smoke from fires?

When you cannot avoid going outside when there’s smoke, N95 masks can provide some protection. These masks filter out most fine particles in smoke but not harmful gases, such as carbon monoxide. N95 masks can be found at many hardware stores, home repair stores, and pharmacies. Remember, N95 masks require proper size and fit to achieve a seal that provides protection. If worn improperly, they may provide less protection. For example, beards and facial hair may prevent a proper seal, meaning less protection. Watch this video on how to properly use an N95 mask.

Additionally, adult small N95 masks will likely fit children ages 7 and older, however smaller sizes are not available, and N95s have not been tested for broad use in children. See the Western States PEHSU guidance (PDF) for more recommendations for mask use for children.

Wearing a mask makes it more difficult to breathe. Anyone with lung disease, heart disease, or who is chronically ill should consult a health care provider before using a mask.

More information on proper use and fit and how to identify if a mask is NIOSH-approved:

In indoor spaces where you cannot keep windows closed or filter indoor air, wearing an N95 mask for short periods could be helpful if outdoor smoke levels are high. Examples of these indoor spaces include public transportation and commercial or public buildings.

Watch this video on how to properly use an N95 mask.

How can I improve air filtration in my home to reduce smoke levels?

Filtering the air in your home can improve your indoor air quality and reduce your exposure to smoke. Three filtration options are described below. Keep in mind, there are different considerations and supplies with each of these options. Try to buy any needed materials before wildfire season as supplies will sell quickly once wildfire smoke arrives. Wildfire smoke season typically starts in July or August, but can begin as early as May.

1. If you have a heating, ventilation, and/or air conditioning (HVAC) system, use a filter rated for particle removal. This will reduce fine particles from wildfire smoke throughout your home.

  • Consult your HVAC manual or consult with an HVAC professional before making improvements.
  • Use a MERV 13 rated filter or the highest rated filter your system can handle. Select a filter with the deepest pleat your system can accommodate to prevent excess strain on the system. The filter must fit tightly. For more information, see EPA's What is a MERV rating?
  • Set the system fan to recirculate and continuously run on the fan mode. (Make sure your system is set to “on”, not “auto”)
  • If you do not have a MERV 13 filter, close the fresh air intake to keep smoke out. Reopen it when air quality improves (See “How can I find out about the current air quality?” above).
  • Remember to replace the filter when dirty or as indicated by the manufacturer's instructions or an HVAC professional. Filter replacements will be needed more often during long periods of smoke.

2. HEPA portable air cleaners can improve indoor air quality by removing particles from smoke in a single room or designated space. HEPA air cleaners that include carbon filters can also remove some harmful gases from indoor air.

Choose a portable air cleaner that is:

  1. Filter only – no ionic, ozone, or ultraviolet (UV) technologies.
  2. A High Efficiency Particulate Air (HEPA) filter.
  3. The right size for your room.
  4. Not too loud.

For more information see:

3. Making your own box fan filter (also called a DIY box fan filter) can be a less costly option to filter air and improve indoor air quality in a single room or designated space.

  • Select a standard 20” x 20” box fan (2012 or newer)
    • What to look for in a box fan:
      • Look for a fan that says UL-listed or ETL-listed under the product details. Newer models have added safety features.
      • Box fans built before 2012 may pose a fire risk. If you use an older model fan, do not leave it unattended or use while sleeping.
      • It's helpful to select a fan where the control settings and power cord are on the outside rim of the fan so they are accessible after the filter has been attached.
  • Attach a 20” x 20” MERV 13 filter to the box fan. If you are using 1 MERV filter, you can use a bungee cord, clamps, tape, or screw the filter to the fan using brackets. See more information here:
  • You can also consider using two or more filters. Using multiple filters can reduce the burden on the fan motor. See an example of a DIY Box Fan Filter with 2 filters here:
  • See an example of a DIY Box Fan Filter with 4 or 5 MERV filters here:
  • Follow the box fan manufacturer’s instructions, including
    • Do not leave children unattended when in use.
    • Do not use an extension cord.
  • Place the box fan filter in a room where you plan to spend most of your time and where you can keep windows and doors closed. It will be more effective in smaller rooms and where  doorways to other rooms can be closed.
    • Position the filter at least a foot away from walls, furniture, or other objects so the air flow of the fan is not blocked.
    • Do not operate in a window.
    • Puget Sound Clean Air Agency found that it takes at least 10 to 15 minutes to clean a smaller room (15’ x 15’).
  • Keep windows and doors closed.
  • Change the filter when dirty. This may be more often during smoke events.

When building your own box fan filter, it is important to understand its limitations. While testing by UL in collaboration with EPA found no safety concerns with fans from 2012 or later, box fans are not designed to operate with a filter attached, and effectiveness varies with the design and supplies selected. EPA does not recommend them as a permanent alternative to products of known performance, like commercially available HEPA portable air cleaners.

For more information about keeping indoor air free of smoke, see EPA's Indoor Air Filtration Factsheet (PDF).

  Should I exercise outside when it's smoky?

Exercise is very important for health. However, when you exercise, your air intake increases, which means you breathe in more pollution when the air quality is bad. During smoke events, try to exercise indoors. If your indoor air is smoky, keep your activities light. As general guidance, if you are sensitive to smoke, you should limit your activities when air quality is in the Unhealthy for Sensitive Groups category (Orange, AQI 101-150) or worse.

People have a wide range of responses to smoke at low and high levels, and it is important to pay attention to your own symptoms and adjust your activities as needed. It’s also important to remember that even if you feel ok during the activity, smoke exposure can still harm your health, and you may have symptoms hours or days later.

Some people are especially sensitive to lower levels of smoke and may start to have symptoms when air quality is in the Moderate category (Yellow, AQI 51-100), such as people with asthma and lung and heart conditions. If you are especially sensitive to lower levels of smoke, we recommend taking steps to reduce exposure at that level.

You should also avoid giving your pet outdoor exercise during periods of poor air quality. Take pets outside for brief bathroom breaks only. See “What should I do to keep my pets and livestock healthy when it’s smoky?".

What should I do if I have to drive when it's smoky?

Avoid driving, when possible. If you must drive, keep the windows closed. Use the air conditioner and set filtration to recirculate. Most vehicles can recirculate the air inside the car, which will help keep the smoky air out; however, carbon dioxide levels can build up and cause sleepiness. You may have to shift from recirculating air to drawing in fresh air periodically. Remember to maintain your car intake filters and seek service when necessary. Smoke can also impact visibility, and you may need to adjust as you would during other weather hazards to drive safely.

What can parents and schools do to protect children and students during smoky conditions?

Children and youth are more sensitive to health effects from smoke because children breathe in more air for their body weight compared to adults. This increases their total amount of air pollution that is breathed in. The respiratory system also develops until about age 21. Children and youth with health conditions (like asthma and other lung diseases, heart disease, and diabetes) have a higher risk of emergency department visits and hospitalizations compared to children and youth without health conditions. They may also be at risk for declines in academic performance, neurodevelopmental problems, and chronic conditions in adulthood from air pollution exposure.

Parents: 

For additional information, see Protecting Children from Wildfire Smoke and Ash, PEHSU (PDF)

Schools:

Additional technical guidance and risk communication resources for public health, air quality, and other officials is available in the Wildfire Smoke – Partner Toolkit

Can smoke impact my mental health?

Long periods of smoke can impact mental and behavioral health. Wildfire smoke and disasters impact our daily routines, including limiting the time we spend outside and altering our activities. Some people may feel isolated from staying inside or sad from the lack of sunshine. Smoke is also a direct threat to health and safety. Protecting mental and physical health are both extremely important.

Here are some things you can do for your mental health during smoke events:

  • Social connection is key. Identify someone you can ask for help and someone else who may need your help. Check in with loved ones and neighbors.
  • Spend time with loved ones in areas of the home that have cleaner air or go to an indoor public space with cleaner air together, such as a library, mall, or other space with filtered indoor air.
  • Build DIY box fan filters together.
  • Get some light exercise indoors.
  • Spend time and play games indoors with your pets to get them some exercise as well.
  • Read more about Coping with the Stress of Wildfire Smoke (PDF).
What should I do to keep my pets and livestock healthy when it’s smoky?

Smoke can affect animals’ health too. Watch animals when the air quality is bad, especially those with heart or lung conditions. If your animals are showing any signs of smoke irritation, contact your veterinarian:

  • Coughing or gagging.
  • Difficulty breathing, including open mouth breathing, increased noise when breathing, or increased breathing rate, or all three.
  • Nasal discharge.
  • Fatigue or weakness.
  • Disorientation or stumbling.
  • Reduced appetite and/or thirst.

Support your pets by:

  • Keeping them indoors as much as possible and avoid outdoor exercise.
  • Keeping outdoor bathroom breaks short.
  • pending time with them indoors and playing games with them to keep them mentally and physically active.

*Pet birds are particularly sensitive to smoke and poor air quality and should avoid any outdoor exposure. 

For more information, see Protect Your Pets from Wildfire Smoke, EPA (PDF)

Support your livestock by

  • Limiting their exercise and having plenty of fresh water always available near their feed or hay.
  • Soaking hay to prevent them from breathing in dust particles that might further irritate the airways.
  • Limiting dust exposure by feeding low-dust or dust-free feeds and sprinkling or misting the livestock holding area.
Livestock may need several weeks to recover after a poor air quality event. Talk to your veterinarian about how to best monitor your animals and when to return to exercise, handling, moving, or transporting them.

For more information, see Protect Your Large Animals and Livestock from Wildfire Smoke (PDF).

Smoke from Fires Information in Other Languages

Resources

Department of Ecology Resources
Additional Resources