By now you know how effective face masks are at slowing the spread of COVID-19. But perhaps you’ve noticed lately that some people are donning not one, but two face masks when out in public. From top infectious disease expert Anthony Fauci, M.D. to inaugural poet Amanda Gorman, double-masking is definitely becoming more common. So, should you be following their lead? Here’s what the experts say about double-masking for COVID-19.
Why Mask-Wearing Is Important
The Centers for Disease Control and Prevention (CDC) cites multiple studies supporting the effectiveness of wearing a face mask to protect against COVID. In one such study, researchers looked at a “high-exposure” event in which two hairstylists (both wearing masks) who had symptomatic COVID-19 interacted with 139 clients (also wearing masks) during an eight-day period, for an average of 15 minutes with each client. Despite that exposure, the research showed that, of the 67 clients who consented to COVID testing and an interview for the study, none of them developed an infection, according to the CDC. Therefore, the salon policy requiring masks to be worn by stylists and clients “could mitigate the spread of infection in the general population,” researchers concluded in the study.
Another study of a COVID outbreak on the USS Theodore Roosevelt plane found that, even in the tight quarters of the aircraft, using a face mask on-board was associated with a 70 percent reduced risk of developing COVID-19, according to the CDC.
Does Double-Masking Double the Protection?
While there isn’t any published research on double-masking just yet, the approach is Fauci-approved. “It likely does [offer more protection against COVID-19],” Dr. Fauci said in a recent interview with Today. “This is a physical covering to prevent droplets and viruses from getting in. So, if you have a physical covering with one layer, and you put another layer on it, it just makes common sense that it likely would be more effective.”
Different than double-masking, the emphasis on wearing a mask with multiple layers isn’t new. For the past several months, the CDC has recommended wearing masks that have “two or more layers of washable, breathable fabric” rather than a single-layer scarf, bandana, or neck gaiter. More recently, infectious disease experts Monica Gandhi, M.D. and Linsey Marr, Ph.D. published a paper in which they wrote that based on the COVID-19 science currently available, they recommend wearing “a cloth mask tightly on top of a surgical mask” for “maximal protection.” “The surgical mask acts as a filter and the cloth mask provides an additional layer of filtration while improving the fit” so the masks sit more snugly against your face, they wrote in the paper. That said, the researchers also wrote that they’re proponents of wearing just one “high-quality surgical mask” or one “fabric mask of at least two layers with high thread count” for “basic protection.”
Translation: Double-masking probably offers more protection, but filtration and fit are the key details to pay attention to here, says Prabhjot Singh, M.D., Ph.D., chief medical and scientific advisor of CV19 CheckUp, an online tool that helps evaluate your risks associated with COVID-19. “To make it simple, there are two types of masks out there — low filtration (low-fi) and high filtration (hi-fi),” explains Dr. Singh. “A typical cloth mask is ‘low fi’ — it captures about half of the aerosol that comes out of our mouths.” A “high-fi” mask, on the other hand, catches more of those aerosol droplets, he continues. “A blue surgical mask gets you 70 to 80 percent [of the aerosol droplets], and an N95 captures 95 percent,” he explains. So, wearing two “low-fi” masks (i.e. two cloth masks) will certainly offer more protection than just one, and opting for two “high-fi” masks (i.e. two N95 masks, for example) is even better, he explains. FTR, though, the CDC recommends prioritizing the use of N95 masks for people working in high-risk environments, such as hospitals and nursing homes.
However, extra layers of filtration are essentially useless if the masks just don’t fit, notes Dr. Singh. “A snug fit is critical,” he explains. “Filtration doesn’t matter if you have a big hole between your face and masks. Some people do the ‘blow a candle test’ [i.e. try to blow out a candle while wearing your mask; if you can, that means your mask isn’t protective enough] to see if they can feel any air come out past their mask, or you can read something out loud to see how your mask moves” while you talk, he says. If your mask seems to slip and slide all over the place while you’re speaking, then it’s probably not tight enough, says Dr. Singh.
When should you double-mask?
It really depends on how high-risk of an environment you’re in. “Normally speaking, a simple cloth mask (not double-masking) would suffice in everyday situations where you can mostly social distance,” says Edgar Sanchez, M.D., infectious disease specialist and vice chairman of Orlando Health Infectious Disease Group. “However, if you are in a situation where you cannot socially distance for prolonged periods of time — such as a crowded airport or a crowded line at the store — then it would be beneficial to double layer if you can, especially if you have only cloth masks available.”
If you’re a high-risk worker with lots of exposure (i.e. those who work in a nursing home), double-masking can help reduce your risk of catching (or spreading) COVID as well, says Dr. Singh. (In fact, you’ve probably already seen health care workers doubling up on masks throughout the pandemic.)
Double-masking might also be a good idea if you’re sick with COVID-19 and want to ensure optimal protection for both yourself and those around you while you’re infected, adds Dr. Singh.
If you’re wondering whether it’s safe to double-mask while exercising, Dr. Singh says it depends on the person. Overall, though, “a tightly woven cloth mask should be fine” for workouts, he says. “Put your masking choice in the context of what you’re doing,” he adds. “For people with breathing difficulties, they should consult with their doctor about the best way to protect themselves and those around them.”
How to Double-Mask to Protect Against COVID-19
While N95 masks are the gold standard, again, the CDC still recommends that only high-risk health-care workers should use them at this time to avoid shortages.
“For those of us who have bought cloth masks and surgical masks, there are a few combinations that are a step up” from a typical single-layer cloth mask, says Dr. Singh. One option is to double-mask with “tightly woven cloth masks,” which you can easily find on Etsy, Everlane, Uniqlo, and other retailers. (See: These Are the Most Stylish Cloth Face Masks)
Double-masking with a surgical mask (which you should be able to find at your local drugstore or on Amazon) and a cloth mask is “even better,” notes Dr. Singh. In their paper, Marr and Dr. Gandhi recommended wearing the cloth mask on top of the surgical mask for the best protection and the best fit. Similarly, if you happen to have an N95 mask, Dr. Sanchez recommends layering the cloth mask on top of the N95 for the best protection and fit.
Bottom line: Experts aren’t exactly urging the public to double-mask as a necessity, but they’re definitely on-board with the approach. Considering there are multiple new (and potentially more contagious) COVID-19 strains circulating around the globe right now, it might not be such a bad idea to double up.
The information in this story is accurate as of press time. As updates about coronavirus COVID-19 continue to evolve, it’s possible that some information and recommendations in this story have changed since initial publication. We encourage you to check in regularly with resources such as the CDC, the WHO, and your local public health department for the most up-to-date data and recommendations.