In the summer of 2023, a terrible and lingering fog covered the entire East Coast. Record wildfire season in Quebec. New York City’s Air Quality Index reached a hazardous level of 465 as smog spread over cities like Boston, Washington, DC and Philadelphia. Before it was finally cleaned up, more than 350 million people were exposed to record levels of unhealthy air.
Canada is battling hundreds of wildfires again this year. Shifting winds are once again driving wildfire smoke across the U.S., triggering warnings in cities outside of regions typically associated with wildfire risk. Minneapolis, Chicago, and Detroit (where I live) are all in between currently the most affected cities.
If you’re like me and deal with sinus pressure and allergies, you may even be feeling the effects of this air quality warning indoors. Here are three tricks I use to minimize the effects of bad air quality in my car when you have to go outside during a warning.
Check the Air Quality Index
If possible, try to do everything in one trip
The EPA’s AirNow tool takes readings from official monitoring stations across the country and turns them into a simple, color-coded score for your zip code. operates as a website at airnow.gov and as a free app for iPhone and Android.
As for the screenshot above, I know it’s pretty bad in Detroit where I currently live. If there is a similar warning in your area and you are able, try to complete your tasks at another time. in the year interest in better fuel economyI combine my errands and grocery shopping into one trip, but I find that strategy also helps when air quality alerts are forecast.
Several states also have their own air quality trackers, often monitoring at a specific location or even at the neighborhood level. For example, the Texas Commission on Environmental Quality publishes a daily outlook For metro areas throughout the Lone Star state New York Department of Environmental Protection.
You can also search for “(your state) air quality”, which should turn into a more local option if available.
Check your cabin air filter
Look for the “MERV-13 equivalent” rating
Almost every car sold in the last two decades has a cabin air filter attached behind the glove box or under the hood that catches dust, pollen and other particles before they reach the air vents. Prolonged exposure to forest smoke, in addition to dust and pollen on a normal day, can shorten the life of your cabin air filter.
In the dash cam footage above, you can see me driving in metro Detroit, including merging onto I-696. The sky is hazy and gray and you can feel it in your lungs the moment you step outside, even if it’s only a short distance from your car.
If your cabin air filter hasn’t been changed in a year or more, or you can’t remember the last time you changed it, now is a good time. You can do it yourself at home or have it replaced mechanically next time for an oil change.
Even though it uses a different filter rating system than cars, your home is dealing with the same fire smoke as your car. MERV or Minimum Effectiveness Reporting Valuemeasures how well a home HVAC filter captures particles by size, with a range of 1-16 (the higher the number, the smaller the particles it filters). The EPA recommends a rating of 13 or higher to filter indoor fire smoke.
Some aftermarket car brands advertise high-end cabin filters as “MERV-13 equivalent” by comparison, using electrostatic, multi-layer designs to trap fine particles.
Go to recycle mode
Change the cycle on longer trips
In Detroit, I like to cruise the main roads like Telegraph and Woodward with my windows down and sunroof open, but when there are air quality warnings, I just turn on the A/C.
The The HVAC system in your car it draws air from two sources, either outside the car or inside the cabin. On most cars, the recycle button is indicated by a small curved arrow or circle with a silhouette of the car. Pressing it stops the system from drawing in outside air and instead recycles what’s already inside.
The recirculation mode does not heat or cool the air on its own; it just changes where that air comes from. Even when paired with air conditioning, I find that it cools the interior as often as it draws outside air, even on a hot day.
Some new cars are equipped with air quality sensors that detect pollution and automatically switch to recirculation mode.
One last tip while driving
Air quality warnings are usually eased after the weather system has passed and the smoke has cleared, although the timeline varies from event to event. Until then, the above tips can help keep the air inside your car a little cleaner and fresher than the air outside.
As a final tip, remember that the recirculation mode traps your exhaled carbon dioxide inside the cabin. On longer drives, that is may make you feel drowsy. If there is a long road trip on your scheduletry to alternate between a regular routine and a periodic cycle.
