Public health officials are suggesting double masking as a way to increase the level of protection from the coronavirus and its multiple, more contagious variants. The change can be as simple as slapping a second mask over the one you already wear, or better yet, donning a fabric mask on top of a surgical mask.
The CDC encourages Americans to choose well-fitting masks with “two or more layers of washable, breathable fabric” and to avoid surgical masks and other face coverings meant for health-care workers.
"If you have a physical covering with one layer, you put another layer on, it just makes common sense that it likely would be more effective, and that's the reason why you see people either double masking or doing a version of an N95," Dr. Anthony Fauci, now chief medical adviser to President Joe Biden, told NBC's Savannah Guthrie.
In mid-December, Linsey Marr, a professor of civil and environmental engineering at Virginia Tech and a leading expert in aerosol transmission of viruses, and Dr. Monica Gandhi, a professor of medicine at UCSF/San Francisco General Hospital, published a commentary calling for double masking.
"For maximal protection," Marr and Gandhi suggested the public could "wear a cloth mask tightly on top of a surgical mask where the surgical mask acts as a filter and the cloth mask provides an additional layer of filtration while improving the fit."
A second option, they said, could be to wear a three-layer mask made from a flexible, tightly woven fabric that conforms to the face, with an insert of a "non-woven high-efficiency filter material," such as a vacuum bag.
When you choose your cloth mask, you should look for a tight weave, according to studies. Use the light test to check the weave: If you can easily see the outline of the individual fibers when you hold up the mask to the light, it's not likely to be effective.
Sources: CDC, The Washington Post, USA Today