Natural Disasters and Severe Weather
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Environmental Health Division
Wildfire Smoke - a Growing Health Concern
Wildfires are becoming more frequent and intense in the United States and Canada, partly due to climate change. Even if a wildfire is burning far away, the smoke can travel thousands of miles and still harm your health. You might see a hazy sky or smell smoke, even on a clear day.
Wildfire smoke can harm anyone’s health
Wildfire smoke contains fine particles (PM2.5) that are small enough to enter deep into your lungs and even pass into your bloodstream and heart. Short-term effects over just a few days can include:
- Coughing, wheezing, or shortness of breath.
- Burning eyes or throat.
- Headaches, dizziness, or nausea.
- Worsening of asthma and or COPD symptoms.
- Increased risk of heart failure, heart attack, or stroke.
- Increased risk of emergency room visits, hospital admissions, and adverse birth outcomes.
Some people are more at risk
While smoke in the air can affect anyone, certain people are especially vulnerable.
All children (0-18 years)
Are considered sensitive to air pollution, including wildfire smoke.
Adults 65 and older
Have a higher prevalence of lung and heart diseases, and the body’s defenses decline with age.
Pregnant people
Have physical changes like increased breathing rates and blood volumes. Smoke could also impact the health of the developing fetus.
People with breathing or heart conditions
Like heart disease, asthma, or chronic obstructive pulmonary disease (COPD).
Outdoor workers and regular outdoor exercisers
Are at greater risk on alert days since they may be outside longer or doing strenuous activities.
Under-resourced people
Are already burdened by air pollution from roadways, freeways, and heavy industry, or already have higher rates of heart and lung diseases.
Take steps to protect your health
When air quality is poor, here’s what you can do:
Stay indoors when air is unhealthy
- Keep windows and doors closed.
- Run your central air conditioner and make sure the system has the fresh-air intake closed / set on recirculate.
- Use an air purifier – HEPA or MERV-13+.
- Use a portable air cleaner or make a Corsi-Rosenthal box – a simple air cleaner using a box fan and a few air filters.
- Learn more about Ventilation and Filtration.
- Find an indoor public space that has air conditioning, like a library or community center.
- Don’t run bathroom or kitchen fans that pull air in from outside.
- Avoid smoking, frying or broiling food, burning candles or incense, using a gas stove, or vacuuming.
Take care of yourself and others
- Take it easy, listen to your body, and pay attention to your symptoms.
- Monitor your body for any changes in your breathing or health.
- Check on neighbors, especially older adults and people who live alone.
- Managing Your Asthma – MDH
- If you have asthma or other breathing conditions, like COPD, make sure you have your rescue inhaler with you.
- Prevent asthma symptoms and flare ups by staying away from things that make your asthma worse.
- Seek medical attention for difficulty breathing, chest pain, persistent cough or sneezing, eye irritation, or dizziness or confusion.
If you must be outside
- Limit strenuous activities.
- Wear a well-fitting N95, KN95, or P100 mask – don’t rely on dust, cloth, or surgical masks.
- Take breaks in clean-air spaces.
- In your car, close windows and set the ventilation to “recirculate”.
- Choose less congested roadways – avoid unnecessary driving.
- Postpone outdoor burning, gas-powered yard work.
- Limit pets’ time outside and monitor for signs of distress.
Protecting outdoor workers
Outdoor workers often can’t choose to avoid smoke. Employers should:
- Monitor air quality often.
- Reschedule or relocate work indoors when air quality is poor.
- Provide clean air breaks and respirator masks.
The Occupational Safety and Health Administration Wildfires webpage provides information to help workers and employers prepare for a wildfire.
Choosing safe activities for schools and childcare centers
Schools and childcare centers can use the outdoor activity guidelines found at Minnesota Outdoor Air Quality Guidance for Schools and Child Care to determine when and how to adjust outdoor physical activities when air quality starts to reach unhealthy levels.
Know when the air is unhealthy
Check air quality every day, like the weather, to be prepared for unhealthy air.
- Visit the Minnesota Pollution Control Agency’s Current air quality conditions and sign up for air quality alerts.
Understand the AQI
This is a simplified view of the Environmental Protection Agency’s (EPA) index for reporting air quality.
| Daily AQI Color | Levels of Concern | Description of Air Quality |
|---|---|---|
| Green | 0 to 50 | Good |
| Yellow | 51 to 100 | Moderate |
| Orange | 101 to 150 | Unhealthy for sensitive groups |
| Red | 151 to 200 | Unhealthy for everyone |
| Purple | 201 to 300 | Very healthy for everyone |
| Maroon | 300+ | Hazardous for everyone |
Hot weather can make air worse
Wildfire smoke reacts with sunlight to form ground-level ozone, another dangerous pollutant. Hotter, drier conditions during the summer can also result in increased fine particulate matter from wildfire smoke or dust. When heat and smoke combine, the health risks increase – even more than either alone.
Learn more about ways to stay safe during extreme heat at Extreme Heat.