N.W.T.'s chief medical official says healthy people whose lungs get irritated by forest fire smoke will recover a few days after the smoke clears.
Dr. Andre Corriveau, the territory's chief medical officer of health, says data from previous wildfires in California and Australia help determine what effects smoke can have on a person's health.
He says "prolonged" exposure to smoke is measured in years, not in weeks.
"It does have a health impact that can be quite serious for people who have predisposing conditions but for the average person they seem to recover fairly well, and whether it's one week or six weeks it's still considered relatively short exposure," he says.
Corriveau cautions people with pre-existing health conditions like heart problems, asthma or other lung problems, to stay indoors and limit outdoor activity when the smoke is noticeably thick.
Corriveau says this applies especially to the elderly, pregnant women, newborn babies and young children.
Air pollution levels in Yellowknife have frequently gone off the chart in recent weeks as smoke from some the territory's nearly 300 forest fires blows into the city.
Earlier this week, Yellowknife resident Dale Bouchard said she was getting out of town so her kids could breathe some clean air.
"I'm getting sick of it and I'm really, really disappointed and actually very confused as to why the territorial government hasn't done something for the people of Yellowknife and the Northwest Territories," she said.
"The kids have been smelling this heavy smoke all summer. They're coughing, got headaches. We have to keep them indoors all the time and it's just been awful, even for adults."
Resident Jonathan Churcher said he has taken to wearing a face mask.
"What are we actually breathing? What toxins are in the air," he said.
He said his mask isn't airtight, "but it does flex as I breathe in and out so I know a lot of the air is actually coming through the filter."
Masks have pros and cons
For workers who spend most of the day outside, Corriveau suggests taking more frequent breaks, longer breaks and going indoors to a place where they can recuperate.
He says workers can also ask a supervisor for a specialized face mask.
"An N95 mask can make a difference although they're uncomfortable to wear, especially if you're exerting yourself," he said.
"People can take more frequent breaks, longer breaks and go indoors and go to a place where they can recuperate."
Corriveau says only N95 or N99 masks will make a difference in filtering particulates. But he warns that, besides being uncomfortable, the mask will stop working as soon as it gets humid and on a hot day, and an N95 or N99 mask will only last half an hour before it has to be changed.