Natural Disasters and Severe Weather
Related Site
Environmental Health Division
Wildfire Smoke

What’s happening
Wildfire smoke is becoming a more frequent part of life in the U.S. and Minnesota – even when wildfires burn thousands of miles away. In the past five years, Minnesota has issued more air quality alerts due to wildfire smoke than ever before. Hotter, drier conditions are creating longer fire seasons and more intense fires. When smoke drifts into our region, skies turn hazy, the air can smell burnt, and health risks rise.
How it affects our health
Wildfire smoke is a harmful mix of pollutants with tiny particles that can get deep into the lungs and even enter the bloodstream.
Short-term exposure, even a day, can cause:
- Coughing, wheezing, shortness of breath.
- Irritated throat, eyes, sinuses.
- Headaches, dizziness, nausea.
- Tiredness.
- Worsened asthma and other lung conditions.
- Increased risk of heart issues and stroke.
Long-term effects we’re still learning about include:
- Pre-term birth and lower birthweight.
- Increased risk of cancer, dementia, and cognitive issues.
- Increased risk of mental health issues.
Who’s most at risk?

Breathing wildfire smoke can affect anyone, but some of us are more at risk, such as:
- Children (0-18 years).
- Older adults (65 years and older).
- Pregnant people.
- People with breathing or heart conditions.
- People with diabetes.
- Outdoor workers and regular outdoor exercisers.
- Under-resourced people and people with multiple exposures, like living near a highway.
What to do
Go to AirNow.gov or use the AirNow app to check current and upcoming air quality conditions so you can plan ahead.
- Breathing wildfire smoke is harmful to everyone, but people in sensitive groups are at higher risk and should take extra steps to protect themselves.
- Sensitive groups include all children; adults age 65 and older; pregnant people; and those with diabetes or heart and lung conditions.
- Wildfire smoke damage is cumulative. Some people might not feel the effects after one day of exposure, but repeated exposure can lead to serious long-term health problems.
Learn what each Air Quality Index or (AQI) color means so you can protect yourself and those you care for.
- When possible, stay indoors with windows and doors closed, and filter the air.
- Run your air conditioning on recirculate with the fresh-air intake closed, and use a MERV 13 rated filter or higher in your heating, ventilating, and air conditioning (HVAC) system. Check the filter at least every month during heavy use and more often during wildfire smoke.
- Use a portable HEPA (high efficiency particulate air) air cleaner, or build a simple Corsi-Rosenthal Box using a box fan, duct tape, and filters.
- Go to an air-conditioned public space like a library or community center.
- Avoid activities that create indoor air pollution, such as smoking, vaping, frying or broiling food, using gas, propane, or wood-burning stoves and furnaces, and vacuuming (unless you use a vacuum with a HEPA filter).
- If you must go outside when air quality is unhealthy, try to limit or reduce outdoor activity – especially exercise – and take it easy.
- Adjust activities as needed to help children stay active while protecting their health. Find more information at Minnesota Outdoor Air Quality Guidance for Schools and Childcare.
- Wearing a well-fitted N95 or KN95 mask can help block smoke particles. Dust, cloth, and surgical masks do not protect against these particles.
- Take breaks in clean-air spaces.
- In your car, close windows and set the ventilation to recirculate.
Have a backup indoor location or an alternate date for outdoor events in case of poor air quality.
- Take it easy and pay attention to how you and others feel.
- Watch for symptoms and monitor any changes in your breathing or overall health.
- Check on neighbors, especially older adults and people who live alone.
- When deciding whether to spend time outdoors on bad air days, consider whether anyone involved is part of a sensitive group, and make the choice that best protects their health.
- If you have asthma or other breathing conditions, such as chronic obstructive pulmonary disease (COPD), keep your quick relief inhaler with you when air quality is poor, make sure it isn’t expired, and follow your medical or asthma action plan.
Seek medical care if you experience difficulty breathing, chest pain, a persistent cough or sneezing, or dizziness or confusion.
Limit your pets’ time outdoors and watch for signs of distress, including coughing, difficulty breathing, or disorientation. Find more information at Wildfire smoke and animals | American Veterinary Medical Association.
What’s the AQI?
The U.S. EPA’s Air Quality Index, or AQI, is a tool to communicate about outdoor air quality and health. It uses a 0 to 500 scale to show how clean or polluted the air is. Higher numbers mean the air is less healthy. A simpler version of that scale can be found at Air Quality Index (AQI) Basics.

Outdoor activity guidance
MDH created a guidance document for schools and childcare centers to use to determine when and how to adjust outdoor physical activities when air quality starts to reach unhealthy levels.
- Download the English version: Minnesota Outdoor Air Quality Guidance for Schools and Childcare (PDF).
- Download the Español/Spanish version: Guía de calidad del aire exterior de Minnesota para escuelas y programas de cuidado infantil (PDF).
Solutions

Reducing wildfire smoke exposure isn’t only about reacting to smoky days - it’s also about addressing the root causes, like climate change. Learn more about Minnesota’s Climate Action Framework, our state’s plan to reduce climate pollution and prepare our communities for climate change.
Resources
- AirNow.gov | U.S. EPA
- Current air quality conditions | Minnesota Pollution Control Agency
- Minnesota Outdoor Air Quality Guidance for Schools and Childcare | Minnesota Department of Health
- Smoke-Ready Toolbox for Wildfires | U.S. EPA
Learn more about Climate and Health at MDH.
