Expert advises doubling or upgrading face masks

Some experts are recommending that people wear two face masks or a high-quality N95 mask, depending on the situation, to maximize protection against the spread of coronavirus, according to news reports.

A January 22, 2021 Boston Globe article that examined the science behind the trend toward two masks featured Joseph Allen, associate professor of exposure assessment science at Harvard T.H. Chan School of Public Health. Allen recommended that people tailor their mask choices based on the situation. “If going on a walk outdoors with a friend, a simple two- or three-layer mask will do,” Allen said. “If you’re going to the grocery store or you are an essential worker coming in contact with a lot of people, I recommend wearing a cotton mask over a surgical mask which can catch more than 90% of respiratory aerosols.”

Allen also wrote a January 26, 2021 Washington Post opinion piece in which he urged people to wear N95 masks, which filter 95% of respiratory aerosols, especially if they are indoors. If people are unable to obtain these masks, Allen reiterated that they should use a two- or three-layer cloth mask.

“Choose masks based on the level of risk for that activity. If you’re out for a jog with no one around or on a walk outside with a friend, a simple two- or three-layer cloth mask is fine,” Allen wrote. “But use a hi-fi mask or double-mask if you head indoors. If you’re an essential worker, a hi-fi mask is critical.”

Read the Boston Globe article: Why more people are starting to wear two masks

Read the Washington Post article: Opinion: Everyone should be wearing N95 masks now