Wildfire smoke in Minnesota: How to best protect your health and your home

A smoky skyline
The St. Paul skyline, seen from Indian Mounds Regional Park, is obscured by wildfire smoke during the air quality alert Tuesday.
Ben Hovland | MPR News

Canada’s wildfire season is off to its worst start on record, and with that comes smoke that’s been drifting over the northern U.S. including Minnesota. The smoke greatly impacts our air quality and produces hazy, smoky skies.

Earlier this month, smoke from Canadian wildfires brought the worst air quality to the Twin Cities since records began in 1980. This week it’s back to smoke from wildfires in Ontario and Quebec. An air quality alert is in effect through midnight on Thursday.

Here’s what you need to know anytime the air is smoky, as this unhealthy air becomes more of a pattern and less of a novelty.

How do I protect myself from unhealthy air due to smoke?

The best way to protect yourself from unhealthy air is to stay indoors as much as possible and limit the time you spend outside. If you do spend time outside, avoid exercising or other strenuous activities.

This guidance goes for all people, said Dr. Zeke McKinney, an occupational and environmental medicine specialist at HealthPartners, in an interview with MPR News. 

While those with pre-existing medical conditions (asthma, COPD, heart disease), people who are pregnant, older people, children and people who work outside are most at-risk for becoming sick, “this is something that we should all take seriously,” McKinney said. 

He also recommends people consider wearing a face mask to protect their lungs from smoke and dust. The best options are N95 or KN95 masks, which are more fitted to the face. A particulate respirator such as a P100 from a hardware store is also a good choice to protect against wildfire smoke and ash, according to the U.S. Environmental Protection Agency. Other types of masks and face coverings do not offer as much protection. 

How does poor air quality from smoke affect people?

“This can affect more than just lungs,” Mayo Clinic’s Dr. Greg Vanichkachorn told MPR News. “We’ve also had reports of stinging eyes, runny noses, headaches and fatigue.” 

Potential symptoms from wildfire exposure include coughing, trouble breathing, wheezing, asthma attacks, stinging eyes, scratchy throat, runny nose, irritated sinuses, headaches, tiredness, chest pain and fast heartbeat, according to the Centers for Disease Control and Prevention.

The Environmental Protection Agency says exposure to smoke can also cause illnesses like bronchitis or aggravate existing chronic heart and lung diseases. The fine, microscopic particles in smoke can enter your eyes or respiratory system whether someone is inside or outside. 

“[Particulates] basically make it more difficult for our lungs to stay healthy and to breathe,” Vanichkachorn said.

How can I protect my home from unhealthy air?

Keeping doors and windows closed will minimize the amount of outside air coming into your home. If you have central air conditioning, set it to recirculate air, if possible.

McKinney also recommended that people make sure their furnace and air conditioner filters are clean. If you have central air conditioning, you can install a high-efficiency filter (MERV 13 or higher) to increase air filtration, advises the EPA.

McKinney and Vanichkachorn both say using air purifiers to improve air quality can be effective.

“I wouldn’t say that it cures everything. And it’s not a reason to just, say, you know, sit next to an air purifier and keep the windows and doors open,” Vanichkachorn said.

Air purifiers can reduce indoor air pollution, but cannot remove all pollutants from the air, according to the EPA.

If buying an air purifier isn’t an option, consider making a Corsi-Rosenthal box, which is a do-it-yourself air purifier made of a box fan and a few air filters. 

Avoid doing things that make indoor air quality worse — burning candles or incense, vacuuming, smoking and using stoves, ovens and fireplaces can increase pollution.

Does breathing smoky air have long-term health effects? 

The Minnesota Pollution Control Agency says long-term exposure to polluted air can cause a variety of health problems. 

“For people with asthma or chronic obstructive pulmonary disease (COPD/emphysema or chronic bronchitis), air pollution can make it harder to breathe, trigger asthma attacks or cause wheezing and coughing,” the agency says. “Air pollution also increases the risk of respiratory infections, heart disease, stroke and lung cancer, and more severely affects people who are already ill.”

How long do you need to be outside to be affected by the air?

Everyone is different, but Vanichkachorn said anything beyond a few minutes is enough to cause symptoms.

“Any breath that you take in with this kind of matter in the air … the smoke can be harmful,” he said. “[The] less time that you could spend out there, the better.”

What impact does poor air have on children and babies?

The CDC says kids are more likely to be affected by health threats from smoke because their airways are still developing and they breathe more air per pound of body weight than adults.

Is unhealthy air dangerous for pets and other animals? 

The EPA says just like humans, bad air can get into pets’ eyes and respiratory systems. The organization has guidance on symptoms to watch for and ways to protect pets from wildfire smoke. The advice is largely the same as for people. 

There’s also advice for large animals and livestock.

How do I improve the air quality in my car? 

Using the recirculation button will reduce the amount of new, polluted air entering your vehicle, as well as closing windows and vents, according to the Minnesota Pollution Control Agency.

The MPCA also recommends taking routes that are less congested if there are air quality concerns. Most cars have cabin air filters intended to protect passengers from harmful air. These should be replaced every 15,000 miles or so.

What can I do to improve air quality, or at least not make it worse?

The MPCA offers these tips: Drive less, keep your car in good repair, don’t idle your car, don’t have fires, don’t burn garbage, plant and take care of trees, use hand-powered or electric lawn equipment and use less energy. Here are more details.

How do I find the current air quality?

The EPA uses the AQI (air quality index) to report air quality. Using AirNow.gov, you can type in your location and get an index read and map of the current air quality. The AQI includes guidance specific to children and sensitive populations.

What do the AQI values mean?

Running from 0 to 500, a higher AQI value means more pollution and greater health concerns. A reading of 50 or under is considered healthy air quality, 51 to 100 is moderate, and anything over 101 goes into increasingly harmful categories of unhealthy. This graphic breaks down and further explains the AQI scale.

Should Minnesota expect annual more air quality alerts than in past years?

The state health department says wildfires are larger and more frequent in the United States and Canada, partially because of climate change. More unhealthy air is to be expected due to wildfires this summer.

Tell MPR News