But what about airflow — and simply how hermetic are they?
“For any mask or fancy filter, one thing we need to keep in mind is how well they fit, tightly, to the face,” mentioned Chenyu Sun, an internist at Saint Joseph Hospital in Chicago who just lately co-authored a examine on face masks efficacy.
Dr. Sun mentioned well being care staff usually get specifically fitted for N95 masks, and the one-size-fits-all strategy of outlets is troubling. So is the dearth of steerage for correct use.
“Inside out, upside down, probably even less people know how to take masks off properly without contamination. This also applies to these devices,” mentioned Dr. Sun, who added that sporting doomsday gear could have unintended psychological penalties. “Will the general public really accept these? Now, even for regular masks, there is a lot of debate.”
“People double-take, but I think Canada is very polite so nobody stares too long,” mentioned Mr. Al-Qasi, who wears the BioVyzr round downtown Toronto, the place the corporate relies.
Raina MacIntyre, the top of the Kirby Institute’s biosecurity analysis program on the University of New South Wales and the lead writer on a current face masks evaluation, warns that if these masks don’t “provide a perfect seal on all contact surfaces, unfiltered air will flow preferentially through the gaps. HEPA filters are good for filtering pathogens, but these devices need to be tested for fit and filtration.”
She added: “The reason for needing a perfect seal is to force the air through the filter.”
Real efficacy, she mentioned, means approval by the F.D.A. and the National Institute for Occupational Safety and Health, the company that regulates this type of powered air respirator. “The virus is present in aerosols, so such a device will not be protective.”