Adequate ventilation reduces up to 82% of COVID-19 virus infections in classrooms, according to an Italian study.
Research funded by think tank David Hume compared the circulation of the virus in 10,441 Italian classrooms, 316 of which were equipped with so-called “mechanical” ventilation.
When this system changes the air in a classroom 2.4 times per hour, the number of infections decreases by 40%. If ventilation replaces the air in a classroom 4 times every hour, this rate rises to 66.8%. In an optimal system where the air is changed 6 times per hour, scientists report an 82.5% drop in infections.
These are “preliminary data” that should be taken with a grain of salt, adds Stéphane Bilodeau, a Quebec expert in the field of ventilation and heating, although he considers that “the methodology has meaning and the results have just as much.
“It matches so many other elements. The WHO has confirmed that there is a link between ventilation and infections in the fall of 2020,” he notes.
Quebec is “very, very behind the pack” in this measure to prevent COVID-19, attests Mr. Bilodeau. More than half of the 90,000 classrooms in Quebec are not mechanically ventilated. In primary schools, 64% of premises lack such ventilation.
However, this “mechanical ventilation” involves the circulation of air from the outside to the inside, a system that is not well suited to the winters here.
“Personally, I don’t think that’s an excuse,” says Stéphane Bilodeau, especially since there are solutions other than air change ventilation.
In Ontario, for example, the government will install 40,000 air purifiers in its schools this year, in addition to the 70,000 air filters already purchased last year.
In Quebec, only “a few hundred classrooms are equipped with air filtration,” says Mr. Bilodeau.
“We should consider studies like that here. I wouldn’t be surprised to see the same results. »
This text is taken from our newsletter “Coronavirus mail” of March 28, 2022. To subscribe, click here.