Calls for vigilance are increasing around smog and deteriorating air quality in several regions of Quebec, due to forest fires in the north of the province. But what are the exact risks, and especially for whom? At home, at work, what behaviors should be adopted?
“Bad” air quality
Deemed good Monday morning again, the air quality has since deteriorated rapidly to be considered “poor” over most of the island of Montreal, with an AQI (air quality index exceeding 50 In the west, the index was 80 and above, while in the north it was around 70. Note: this index is calculated from the concentration of five contaminants: ozone, carbon dioxide sulphur, nitrogen dioxide and carbon monoxide, but also fine particles, which are particularly on the rise during this fire season.
Caution for the most vulnerable
“Anyone can be affected by the smoke from the fires, regardless of their age,” notes Marie-Claude Lacasse, spokesperson for the Ministry of Health and Social Services (MSSS). “People might experience tearing, itchy eyes and throat, mild cough, sinus irritation,” she says. But smoke from wildfires “may have a greater impact on people with asthma and those with heart or respiratory conditions, such as emphysema and chronic bronchitis.” These people are advised to be very careful. In the most affected regions, it is recommended to avoid outdoor activities and close the windows, or even close the air exchanger.
Stay isolated first, says Public Health
The Dr Stéphane Perron, of the National Institute of Public Health (INSPQ), says the most important thing – especially for people at risk – “is to stay indoors”. “For the general population, that said, it is not a health concern. The level of particles would have to rise a lot more for parents to be told to stop playing with their children outside, ”he argues. As for wearing an N95 mask, “it’s not really the solution at the moment,” adds Mr. Perron. “We especially want the people who need it to avoid exposure, rather than wearing equipment that is of variable quality installation, and therefore of variable efficiency,” he says.
“Incomplete”, judges an intensivist
For the DD Amélie Boisclair, intensivist, the position of Public Health is however “incomplete”. “It’s okay to say that we can stay indoors when possible, except that in real life, we often have to go outside. Not everyone can stay at home either. They should make it clear: especially if you have lung health issues, having a properly fitted N95 can help,” Ms.me Clear wood. It also draws a parallel with exposure to the sun. “Obviously the best thing would be to stay at home, but because we’re not Dracula, we put on sunscreen. It is a protection tool, like the N95, and it must be said. »
In the workplace, measures to take
The Commission for Standards, Equity, Health and Safety at Work (CNESST) recalls that it is essential to “reduce the exposure of workers and employers to this smoke, to prevent they are inconvenienced”. In buildings, it recommends in particular to “shut down the extraction and ventilation systems using the air recirculation mode when possible”. As much as possible, any work performed outside should also be postponed. If this is unavoidable, the Commission for its part calls on companies to “prefer the performance of tasks inside a filtered and closed cabin or, as a last resort, wear N95 type respiratory protection”.
Why is the sky orange?
No, you are not dreaming: the sky has been orange since Monday in several sectors of the province. But beyond saying that the phenomenon is linked to fires, how can we explain it? It is that “the particles of smoke released into the air increase rapidly”, making the air more polluted, observes the Dr Peron. “The orange halo that we see is the most visible result, but what happens in Montreal depends on the intensity of the fires and especially the winds. As soon as there are changes at this level, it completely changes the situation, since all these particles travel less,” he explains.