Consumer Reports has no financial relationship with advertisers on this site.
Every year raging wildfires create hazardous air-quality conditions across the U.S. As of early July, wildfires have burned close to 1.5 million acres across the country, an uptick when compared with numbers from the same time last year, according to the National Interagency Fire Center.
Smoke from a wildfire can cause your eyes to burn and your nose to run. And the microscopic particles in smoke can get deep into your lungs and cause illnesses such as bronchitis, asthma attacks, and even heart attacks and strokes, according to the Centers for Disease Control and Prevention and the Environmental Protection Agency.
These fine particles have even been linked to premature deaths among people with heart and lung disease. Children who breathe in wildfire smoke can experience chest pain and tightness, wheezing, coughing, dizziness, and trouble breathing.
If you live in an area prone to wildfires, it’s important to keep your indoor air as free of smoke particles as possible, and an air purifier can help. Our tests of air purifiers with HEPA filters show they can get rid of these harmful particulates.
Choosing an Air Purifier for Wildfire Smoke
Not all air purifiers do a good job removing smoke particulates. The most effective against smoke have a HEPA filter, which uses a fan to force air through a fine mesh to trap particles.
The very best air purifiers fitted with HEPA filters can reduce particle concentrations by as much as 85 percent, according to the EPA. If you want to get rid of the smell of smoke in addition to particles, you’ll want an air purifier that also has a large carbon filter to absorb odors.
HEPA air purifiers can range from $50 to more than $1,000. Our experts advise against buying one that is marketed for rooms smaller than 150 square feet. These models tend to perform poorly in our tests, plus you’ll always get better results with a unit that is rated well for a larger space than you have. Purifiers for rooms larger than 350 square feet are much better at removing smoke. Most of CR’s recommended air purifiers fall into that category.
“If you look at any of the top-rated air purifiers tested in our labs, they’re physically big because of the big HEPA filter inside of them,” says John Galeotafiore, associate director of product testing at Consumer Reports. “That’s the one thing they all have in common.”
To test how well these machines trap small particulates from smoke, we inject cigarette smoke particles into a sealed room and use a particle counter to measure the number and size of particles, as small as 0.1 micron, in the room as an air purifier works. Because air purifiers typically have a number of speed settings, we test for smoke removal both at the highest speed and at a lower speed. (Some models that perform well at high speeds don’t do as well at low speeds.)
We also measure noise levels at every speed a machine has because you’ll need to run it 24 hours a day for it to be effective. We also calculate annual operating costs, which include filter replacements and energy use.
For more information on air purifiers, check out CR’s air purifier buying guide. Read on for ratings and reviews of five air purifiers from our tests that work well at reducing wildfire particulates. But note that because of high demand, we’ve seen these models go in and out of stock in recent weeks.
Below, we have more tips for how to keep your home’s interior smoke-free, whether or not you’re running an air purifier.
Best Air Purifiers for Wildfire Smoke
These five air purifiers (listed in alphabetical order) top our ratings chart and pass our tests for particle reduction with flying colors at both high and low fan speeds.
More Tips to Protect Yourself From Smoke
Smoke can travel hundreds of miles from the source, so even if you live far away from a fire and are in no immediate danger, you could still have harmful smoke coming into your house. Using an air purifier helps, but there’s more you can do to keep your home as smoke-free as possible.
Close all your windows and doors tight and seal any air leaks (including the mail slot, if you have one) with weather stripping if available. Even masking tape is better than nothing.
If it's too hot to go without using the window air conditioner, close the outdoor air damper if you can and tightly seal any gaps between the unit and the window.
If you need to leave your house, wear goggles and a face mask approved by the National Institute for Occupational Safety and Health that’s designed to block particles from entering your mouth and nose if you can. If you don’t have an air purifier and the smoke is very bad, consider wearing this protective gear indoors when you can as well. While cloth face coverings and surgical masks provide protection from exposure to COVID-19, they will not protect you from smoke inhalation.
Try to spend the bulk of your time in a room with the fewest windows and no fireplace or ventilation ducts that connect to the outside. If you have a fireplace, shut the chimney flue.
If you have an air purifier, use it in this room and keep it running 24/7.
Change the filter as soon as the indicator light comes on or according to the time frame specified in the manual. If you can’t change it right away, continue to use the air purifier until you can. A dirty filter is still better than not using the air purifier at all.
If you have central heating, ventilating, and air conditioning, you can install a high-efficiency filter (MERV 13 or higher) in the system. Run the system’s fan as often as possible to get the most out of the filter. If your system has a fresh air option, turn it off or close the intake.
Shut doors to the laundry room and bathrooms because those rooms often have ventilation ducts that lead to the outside.
Vacuum cleaners with HEPA filters can help remove and trap smoke particles that have settled onto carpet and furniture. But don’t use a vacuum that doesn’t have a HEPA filter; it’ll just kick up more particles into the air. For the same reason, clean hard surfaces with a damp cloth or mop.