OHS Canada Magazine

From double masking to medical grade masks, is it time to ramp up protection?

Public Health Agency of Canada currently does not recommend doubling PPE


By Melissa Couto Zuber

Increasing concerns over more infectious COVID-19 variants has led some to wonder whether our face masks need an upgrade.

Should we layer two masks on top of each other, as politicians and spectators at the U.S. presidential inauguration did earlier this month? Should we replace cloth masks with medical-grade ones, like some countries in Europe are now recommending? And should we wear masks even when outside?

The Canadian Press asked medical experts these common questions.

Double-masking

Dr. Anthony Fauci, the chief medical advisor to the U.S. president, said recently that wearing two masks “makes common sense,” but experts say there are caveats to that claim.

The idea behind wearing two masks is to add extra layers of filtration, making it harder for viral droplets to spread from person to person.

Advertisement

Dr. Jane Wang, a clinical instructor at UBC who’s studied face masks extensively, said in an email that double-masking might improve fit and can increase that “filtration efficiency.”

If the two masks aren’t snug around the face, however, that won’t matter.

Stephen Barr, an expert in viral pathogens at Western University says masks work by filtering air in and out as we breathe. If too much can sneak through gaps around the sides, “it’s not going to be as effective.”

So a proper-fitting single mask would be better than a doubled-down approach if gaps are still there.

“Without that seal around the skin, there’s no point, in my opinion,” Barr said.

Breathability can become an issue with layering masks, and Barr foresees people pulling at or removing their doubled-up face coverings more often, giving them “more chance to get infected.”

Wang agrees double-masking loses its effectiveness if it causes “overheating, poor breathability or (carbon dioxide) retention problems.”

To shave or not to shave: How do beards impact the effectiveness of face masks?

The Public Health Agency of Canada (PHAC) doesn’t currently recommend double-masking, saying in a statement that “Canada’s context is different from that of the U.S.”

“We will continue to monitor the situation and will adapt our guidance if further such evidence emerges,” PHAC said in an email to The Canadian Press.

The U.S.-based CDC has also not issued guidance on wearing two masks at once.

Dr. Lisa Bryski, a physician in Winnipeg, isn’t aware of any studies on double-masking efficacy, but she still agrees with Fauci’s claim.

“Anything that increases the barriers or ‘obstacle course’ as it’s being referred to, and is still safely breathable, that does make sense,” she said.

Bryski says there are things to keep in mind when layering up face coverings, however. The two masks should be worn with the correct side as inside layer, and “should both fit snugly over your nose, mouth, and chin, with no gaps.”

“And consider making one or both of them medical grade,” she added.

Upgrading to medical-grade masks

Places like France and Germany now recommend surgical masks or medical-grade respirators instead of home-made cloth coverings to slow the spread of more transmissible variants.

Health Canada’s current guidance for the general public is to use a three-layer non-medical mask that fits properly, adding that surgical masks and N95s should be kept for health-care providers and those taking care of COVID-19 patients.

Bryski believes Canadians should consider upgrading to medical-grade disposable masks, which are available at many pharmacies and grocery stores, or even N95s with proper NIOSH or ECAN95 designations, which she expects will become more widely available.

Surgical masks are made of three layers of medical-grade material, including non-absorbable outer sections and a non-woven polypropylene middle that makes it more effective at filtering viral particles.

They are rated by the American Society for Testing and Materials according to the level of protection they provide, from Level 1 to 3.

Byrski also suggests face shields on top of masks, as the new variants take the pandemic “almost back to square one” in terms of what we know of transmission.

“Anything we can do to bump protection we should be doing,” Bryski said, adding that recommendations can be flexible as more info emerges. It’s better to be cautious and downgrade if needed, she explained.

Barr says cloth face coverings might still suffice in most scenarios, but we should also keep a good distance from others while wearing them now — and consider increasing that distance from six feet to 12.

While studies are underway to assess how transmissible the new variants are, Barr says spread could happen with less contact with an infected person, and less droplet exposure.

“In that case, you probably would want more of a form-fitting mask, or keep your distance even more than the normal recommendation,” he said.

Wang says masking is an intervention aimed at “risk reduction not risk elimination,” and the focus should be on wearing masks correctly.

“If this criteria is not satisfied it doesn’t matter if it’s a three-layer mask, double mask, N95 (or) surgical mask,” she said.

Wearing masks outdoors

Outdoor settings have generally proven safer as fresh air and the ability to spread out lowers risk of transmission. That should still hold true with the variants, Barr says, but we do need to be more careful.

Even a brief interaction, like walking by someone on a sidewalk, could be enough to transmit more contagious forms of the virus, Barr says, though the exact amount of time is yet to be determined.

Going for a solo walk with no one around may not necessitate a mask, but a crowded path might.

“It comes down to how long the virus is going to stay in the air,” he said. “Once it’s confirmed that the variant is conclusively more transmissible, I would definitely double the distance to 12 feet if I wasn’t wearing a mask.”

Bryski says we should normalize wearing face masks whenever we leave our homes and suggests carrying multiples that can be switched out if one gets soiled.

The cold winter climate also makes masking outdoors easier, she adds, providing the extra benefit of warmth.

“Canada is lucky in some ways to have that,” she said with a laugh. “But I do think we should start wearing masks outdoors because we don’t know how much more contagious this virus is now and in what environmental capacities.

“We should take a step back and bump up our protections of each other and ourselves.”


Print this page

Related

Tags



Leave a Reply

Your email address will not be published. Required fields are marked *

*