With winter wildfires devastating areas of Los Angeles, you may be wondering about smoke. Large wildfires can spread smoke hundreds of miles, affecting the atmosphere for millions of people and triggering air quality warnings.
You can visit IQAir.com to instantly check your local air quality and to see what the worst regions in North America are (Canada currently has some struggling cities, too). The site estimates that air quality problems cause more than 7 million deaths each year. We asked the experts what you can do to protect yourself.
We spoke with Dan Westervelt and Richard Peltier. Westervelt studies air pollution at the Columbia University Climate School’s Lamont-Doherty Earth Observatory, and he’s served as air pollution advisor to the US State Department. Peltier is a professor in the Department of Environmental Health Sciences at the University of Massachusetts Amherst.
Here’s what we learned.
How dangerous is poor air quality?
Poor air quality can be hazardous for everyone, but especially people with respiratory issues such as asthma; individuals with lung and heart disease; the elderly; and pregnant people.
Wood smoke exposure from trees or homes burning is particularly associated with inducing asthma attacks and aggravating heart disease. That makes people more susceptible to respiratory infections and leads to an increase in deaths.
“Some people might think that wood smoke should be harmless because it comes from a natural resource, in trees, but this couldn’t be further from the truth,” Peltier said. “We know that wood smoke contains many toxic chemicals, some of which are known carcinogens, and there is clear evidence in the scientific research world that links wood smoke exposure to really important adverse health outcomes.”
5 expert-backed ways to protect yourself from smoke
Here are some high-impact steps to take to protect yourself when facing air pollution from wildfires and beyond, according to Westervelt and Peltier.
1. Keep windows and doors closed
Remove any way for smoke to creep into the house, where it can linger. Close doors and windows, and check the insulation around their frames to make sure no air is seeping in.
2. Use air filtration and upgrade filters
Use any air purifiers you have. If you have an air conditioner, switch its filter to a new one to help clean the air.
Peltier also suggested asking your HVAC technician to upgrade your unit’s filters to higher MERV ratings at your next system servicing. MERV is an industry standard that describes how well the filters can remove particulates — the best filters have higher MERV ratings, usually 13 and up. Not all HVAC systems will tolerate higher MERV filters, so it’s important to get expert advice first.
“It’s important to note that most window air conditioning units are not terribly useful to filter out these particles,” Peltier said. “The filter materials they use have a very low MERV rate and don’t do much.”
3. Don’t use appliances that take in outside air
Some appliances, like air conditioners or venting systems, are set to bring in outdoor air as they work. Either turn these appliances off or set them to recirculating modes so they aren’t accessing smoky outside air. When the smoke clears, start moving outdoor air inside to freshen things up.
4. Avoid using gas-powered appliances — or vacuums
Don’t use anything that can worsen the air quality in your home. One of the most common examples are gas-powered appliances, like ovens. I was amazed at how much my air quality plummeted when I used my gas oven in a closed home, and the same can be true of other natural gas or propane appliances.
Also, avoid vacuuming for now. Vacuums stir a lot of dust into the air, worsening air quality and making it hard for filters to do their job. Vacuum once the smoke has cleared.
5. Limit time outdoors and wear a mask
Limiting outdoor time is crucial when air quality is poor, but if you must leave your home, Westervelt suggests wearing a face mask and avoiding strenuous activity that induces heavy breathing, like jogging or running. Both Peltier and Westervelt also recommend that each person in your household wear an N95 or KN95 mask, though a well-fitting surgical mask can also help block the majority of particulate matter.
Air purifiers can help — if you get the right one
Though air purifiers became more mainstream during the COVID-19 era, experts are divided on how effective they are. Manufacturers in the US aren’t allowed to market air purifiers as health products, though CNET’s hands-on testing has shown some to effectively filter particulate matter from the air, especially if they use a HEPA filter.
“For indoor air quality, many air purifiers work well, especially the ones that use high-efficiency particulate filters,” Westervelt said.
We have a guide on choosing an air purifier specifically to deal with wildfire smoke like what we’re seeing right now in California. As someone who’s had to deal with Cali smoke for quite a few years, my personal favorite is the affordable but effective Levoit Air Purifier ($100), which includes HEPA filtering and a constant monitoring of particles in the air so you can check air quality at a glance.
Westervelt recommends avoiding air purifiers that generate ozone, which will be identified as electrostatic and ionizing air purifiers. The US Environmental Protection Agency also warns about the risk of ozone-generating purifiers, since ozone molecules can lead to harmful health consequences such as damage to the lungs.
Peltier said air purifiers can be an effective method for cleaning air, but there are two important aspects to remember: They must be the right size for the space you’re trying to keep clean, and these spaces have to remain closed to the outdoors. He recommends using them only in the places where you spend most of your time and shifting the machine from room to room. For example, moving it to your bedroom at night or into the living room during the day.
Stay informed and be prepared
Westervelt also mentioned that air quality forecasts can give you an accurate read on the air quality index for a given region. He recommends airnow.gov as a real-time source for finding air quality data for your city, state or ZIP code.
Peltier said to hope for the best but be prepared for the worst, considering the health risks associated with ongoing smoke exposure.
“We take about 20,000 breaths per day, and this happens whether the air is polluted or clean,” Peltier said. “When we take a breath, we inhale air, but also the contents suspended in that air, including pollutants, and we draw this into the deepest parts of our lungs. This delivers a wide range of different chemicals into our bodies that cause many adverse health effects.”
For more tips to stay safe, read about how air purifiers can protect you from poor air quality and what to keep in mind when shopping for the best air purifier. You should also make sure your air purifier is in the right place and is clean to ensure it’s working properly.