Pardon the source, but this article has some decent information on Health Canada's recommendation for better quality masks. I wonder if the change has anything to do with the new variants that are starting to spread.
Canada's mask guidance has changed. Here's why you might need an upgrade
COVID-19 mask use: Advice for community settings - Canada.ca
"In general, while non-medical masks can help prevent the spread of COVID-19, medical masks and respirators provide better protection," the Public Health Agency of Canada (PHAC) said on its COVID-19 mask information webpage, which was updated on Nov. 12.
The updated guidance also recommends medical masks or respirators for people "who are at risk of more severe disease or outcomes from COVID-19" and those "at higher risk of exposure to COVID-19 because of their living situation."
Respirators (such as N-95 and KN-95 masks) are considered the highest level of mask protection and were previously recommended only for health-care workers coming into direct contact with infectious patients. In those high-risk areas, respirators require a "fit test."
Responding to a CBC News inquiry about why PHAC's recommendations have changed, the agency said in an email it was "based on the latest scientific evidence on SARS-CoV-2 virus variants of concern, increased understanding of the impacts of vaccination and immunity in the population, and new data available on mask types and their effectiveness."
In addition to the updated online guidance, Dr. Theresa Tam, Canada's chief public health officer, recently posted a series of tweets illustrating how COVID-19 could spread through the air, using the analogy of second-hand smoke.
Many doctors, scientists and engineers say this shift in messaging reflects a growing body of evidence suggesting that COVID-19 is largely spread through aerosols (tiny particles that can hang in the air), and not just through respiratory droplets (larger particles) transmitted by close contact with an infected person.
In turn, that means it's important to re-evaluate the masks we're using, they say.
"This marks a transition in Canada toward a recognition of how important aerosol, airborne-based transmission is in transmission of this virus," said Dr. Brooks Fallis, a critical care physician at the Toronto-area William Osler Health System.
more at link