Global Courant
As smoke from hundreds of out-of-control wildfires dances and lingers over hundreds of North American communities, experts warn of the risks to human health from toxic particles that clouds carry.
And because no home is perfectly sealed, indoor air quality can still be compromised.
“On average, whatever the level of air pollution is outside, it’s probably about half that indoors,” explained Dan Westervelt, an associate professor in Columbia University’s Climate School.
“And when you talk about the kind of levels we’ve seen in the Mid-Atlantic US, half of that is still pretty dangerous.”
So what are some ways this smoke can enter our homes?
Check doors, windows, vents
Of course, the largest openings in our homes to the outside are usually the doors and windows. But even when they’re closed, says Amy Li, an air quality expert at Waterloo University, smoke particles can still “peer into your room through all the cracks and leaks in the building’s fence.”
Experts recommend closing all open windows to keep out harmful particles in wildfire smoke. (Ben Nelms/CBC)
Another source that people may not think about is the ventilation system in some buildings. Li says the particles through these systems are intentionally designed to bring fresh air into an apartment or apartment.
“It’s interesting because we typically need fresh air outside to deal with indoor pollutants,” Li said, recalling the need for fresh air in recent years to reduce COVID transmission. “But in this case, we don’t want it if it’s not filtered.”
Seal the leaks
Closing those doors and windows is the first step during days where the Air quality health index indicates a high health risk, experts say.
Li also suggests that if you know of areas in your home that leak air from the outside or have drafts, they can be blocked with cloths or towels.
Check your air filters
It’s important to keep the air circulating indoors, as these wildfire seasons usually coincide with hot summer temperatures. The effect of heat on the human body can take many forms and air conditioning systems can help – with the right filtration and air source.
“You want to make sure that your ventilation system is turned on and that you have good quality air filters on your ventilation system,” suggests Roshini Kassie, a specialist with Health Canada’s Water and Air Quality agency.
Kassie reiterates that systems should recirculate air, not draw it from the outside. For apartments, Li suggests examining the air handling unit, which is typically located in its own closet.
“Check that it has a high-efficiency filter,” Li described. “If you find that the existing filter is very dirty, maybe consider replacing the filter.”
Use portable air purifiers
For people who don’t have a ventilation system, several experts point to a portable air purifier as a solution. However, not all of these devices are created equal, so Kassie references Health Canada’s advice what to search for.
Some general guidelines are:
Look for HEPA (High Efficiency Particulate Air) filters. Make sure the device is suitable for the size of the room you have. Avoid devices that produce ozone as it can harm your health (it is part of the calculation of the AQHI).
If you have one of these devices, Li says it’s important to use them as often as possible and place them where people will be.
“The goal here is really to protect the occupants,” Li told CBC News, pointing to an air filter placed right behind her seat.
Portable air purifiers with these types of HEPA filters have been used to reduce COVID transmission by capturing small particles in the air. (Evan Mitsui/CBC)
“If you have a large family room where most people gather, maybe after dinner, put a portable air purifier there to help improve the air quality.”
Visit safe common areas
Experts stress that these strategies — the use of portable air purifiers, filtered indoor ventilation, and restrictions on outdoor activities — aren’t always accessible. So the solution may lie outside.
Experts suggest cities could set up shelters for smoky days, similar to refrigeration centers that help people avoid the dangers of extreme heat. (Ben Nelms/CBC)
“A lot of people, if they can’t control or keep the air in their homes clean, they need to go somewhere that has clean air,” Kassie said, using examples of community centers, shopping malls and public libraries. She points to more Health Canada Guidance for cities and counties to create these safe zones in anticipation of and during wildfires.
“Various municipalities can put up that building or such a space to invite people to come out of the smoke.”
Trust your nose
An important reminder as smoke and alert warnings are lifted for some communities, experts say, is to get some fresh air back in.
While checking the Air Quality Health Index can be a good indication of when to do it, Li says it’s still valuable to track your nose.
“I think it’s even more important to rely on your own sense or smell about the smoke,” Li said, because air quality monitoring stations aren’t always near your home.
LOOK | More on reducing the risks of wildfire smoke:
Wildfire Smoke and Your Health: What You Need to Know | About that
Millions of people are receiving air quality advisories as wildfires overshadow large parts of Canada and the US. About That producer Lauren Bird explores how it affects your health – and what you can do to protect yourself.
