The sharp decrease in air quality is mostly due to small particles from the fires that can irritate people's lungs.
The highest concentration of particulate matter in the air has been found in North Burnaby, where levels are not far behind those found in Beijing.
"I would say that the air quality that we've experienced recently and are experiencing now is unfortunately something that residents in a lot of cities in China experience on quite a regular basis," said Fraser Health Medical Health Officer Dr. Lisa Mu. "Which I think is quite concerning because these are certainly levels that pose a risk for human health and wellbeing."
Particulate matter numbers
Beijing: 144 µg/m3
Burnaby north: 112 µg/m3
Vancouver: 60.1 µg/m3
Abbotsford: 58 µg/m3
Paris: 56 µg/m3
Note: These figures are accurate for 7 p.m. PT on Monday. Source: Air Quality B.C.
Air quality advisories issued across the region
The province has issued air quality warnings for Metro Vancouver, the Fraser Valley, Howe Sound and the Sunshine Coast.
"We've seen some short-term concentrations of particulates that are around as much as four times the normal levels," said Roger Quan, the director of air quality policy and climate change for Metro Vancouver.
"It's going to take a change in the weather and an improvement in the fires themselves to clean out the air that we're seeing here in Metro Vancouver," said Quan.
Avoid strenuous exercise, stay indoors
Heath experts warn that vulnerable segments of the population are the most at risk of adverse health effects due to poor air quality.
"People with pre-existing heart or lung conditions, with diabetes, pregnant women, the very young, the very old ... those are the people we're most concerned with," said UBC School of Population and Public Health Professor Michael Brauer.
He said anyone who fits in any of those categories should consider staying indoors and not exert themselves too much.
Brauer advises that even healthy people should avoid strenuous activity outdoors to keep from inhaling too much smoke.
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