How protective are masks when I’m wearing one and others are not?
Masks are most effective when they are blocking particles from entering your mouth and leaving others’ mouths. But N95s and KN95s — considered the gold standard of masks — are still an effective shield against the coronavirus even when you are wearing them and others are not, experts say. The 95 in their name means the mask filters out 95 percent of particles that you would otherwise breathe in.
Linsey Marr, a Virginia Tech engineering professor who has conducted research on covid and masking, emphasized that masks need to fit properly to effectively reduce exposure to coronavirus particles.
“The relationship between infection and exposure is not necessarily linear, so this does not necessarily translate to a 90-95% reduced risk of infection, but there will be a big drop in risk of infection,” she said in an email.
Natascha Tuznik, an infectious-disease specialist at UC Davis Health, notes health-care workers wear N95s for hours on end and are well protected even when patients do not have their faces covered.
“Oftentimes the patients in the hospital aren’t wearing masks … and it confers very good protection,” she said.
