Should You Double Mask in the Workplace?
Wearing a single mask is not effective if air is going around it and not through it, says Dr. Bruce Hirsch, an infectious disease doctor at Northwell Health. But if you only have a surgical mask, you can make it more effective by knotting the ear loops and then tucking in and flattening the extra material close to the face to get a tighter fit.
Both methods substantially reduce your exposure to the aerosol droplets that cause Covid-19. Dr. Hirsch notes that you shouldn't go overboard and wear more than two masks at a time, however. Three is not better than two. If the air resistance through the mask becomes too great, it's more likely you'll lose the tight fit around the mask, which is crucial.
Of course, you also don't want the mask to be uncomfortable. "The most important mask is the one you're going to wear all the time when you're in high-risk situations," says Dr. Bob Bollinger, a professor of infectious diseases at the Johns Hopkins University School of Medicine and inventor of Emocha Health, a medtech company that helps patients adhere to medication. "There's no point in wearing masks if you're not going to use them consistently."