How Well Do Face Masks Work Against COVID?

Do the masks we own now protect against new variants like delta and omicron? Researchers say it's too early to tell.
Posted at 5:46 PM, Dec 21, 2021

Face coverings will continue to be a part of our lives for the foreseeable future. But do the masks we own now protect against new variants like delta and omicron? Experts say it depends on the type of mask.

A University of Minnesota study looked at how long it takes a person to be infected by COVID-19 according to the type of mask they're wearing around an infected person. For example, if the infected person is maskless and you have on a cloth mask, the study found that you have 20 minutes before you're infected. It takes 30 minutes if you're wearing a surgical mask, and 2 and a half hours if you're wearing a fit-tested n-95 or equivalent like a kf94 or kn95. Your protection time increases if the person is also masked. The study suggested the max protection is if both you and the person wear a fit-tested n-95 or equivalent, you're good for 25 hours. 

Infectious disease doctor Christian Ramers says the caveat of this study is that it doesn't account for new variants. 

Unlike last winter, there is no significant PPE shortage, so people do have access to these higher grade masks now, which were originally intended for hospital settings. But if folks still have difficulty finding them, Dr. Ramers says there is another option in a pinch: double-masking.