Discussion of double masking has come to light since the discovery of COVID-19 virus variants. Scientists believe it’s possible that some of these new variant strains can spread more easily and quickly than the original. While double masking could help better protect some people from COVID-19, it’s important now more than ever to continue wearing a mask in public, physical distancing, regularly washing your hands, and staying home when sick. Jeremy Biggs, MD, MSPH, the medical director for occupational medicine at University of Utah Health, offers advice for when to double mask and what types of mask will better protect you.

Three layers are better than one

At the start of the COVID-19 pandemic, surgical masks weren’t widely as available as they are now. People were advised to make their own face masks using breathable fabric. It’s now time to ditch those single-layer masks and switch to a multi-layer one. “I would recommend a surgical mask with several layers over a cloth mask,” Biggs says. Cloth masks are still okay to use, but make sure they have multiple layers. Those who don’t have access to multi-layer face masks can double up their single-layer masks to better protect themselves against the virus.

The Centers for Disease Control and Prevention (CDC) recently provided guidance on masking based on two experiments. Scientists found that wearing a tight-fitting mask can help limit spread of COVID-19 by about 95 percent. This includes wearing a cloth mask over a medical procedure mask, and by knotting the ear loops of a medical procedure mask and then tucking in the sides.

Choose the right mask

According to the Centers for Disease Control and Prevention (CDC), a surgical mask provides barrier protection against large-particle droplets, keeping it from reaching your mouth and nose. Biggs suggests looking for a polypropylene surgical mask that has two or three layers and has been approved by the National Institute for Occupational Safety and Health (NIOSH). Surgical masks are graded by their protection level:

Level 1: Low barrier protection

Level 2: Moderate barrier protection

Level 3: Maximum barrier protection

To better protect yourself from COVID-19, Biggs recommends a level two or level three surgical mask. “In general, the higher the number, the better it is because it has additional moisture barriers,” Biggs says. “The higher-level mask filters out more bacteria than a lower level surgical mask.”

Wearing N95 respirators

N95 respirators reduce exposure to bacteria and viruses by filtering out at least 95% of airborne small virus-sized particles and providing a very close facial fit and filter material that you breathe through. Although the CDC does not recommend for the general public to wear N95 respirators and to reserve them for health care workers and first responders, Biggs says it’s important to keep two things in mind:

1. Whether a person is medically capable of wearing an N95 respirator, and
2. Whether an N95 respirator fits correctly

If there are no medical reasons to wear an N95 respirator, it’s probably best to stick to a surgical mask. N95 respirators are supposed to fit tight around the mouth so that they force air through the filter. “N95 respirators might not work as well if they are not well-fitted,” Biggs says. “If air is passing by the bridge of the nose or under the chin, then the air is not being filtered or blocked in any way. So, it’s just like wearing a regular surgical mask.” The CDC also recommends people with chronic respiratory, cardiac, or other medical conditions that make breathing difficult to check with their health care provider before using an N95 respirator.

Wearing KN95 respirators

KN95 respirators are the standard used in China and are expected to provide equivalent protection against COVID-19 as N95 respirators, according to the CDC. However, Biggs points out these masks don’t fit extremely tight like the N95s because they wrap around the ears instead of the head. “You need to pull KN95 respirators tight, which most people can’t tolerate, or the ears just won’t hold the mask in place,” Biggs says. This is why it’s important to have a KN95 respirator fit tested before wearing one in public to ensure it’s protecting you in the manner you expect.

If you are considered high-risk for COVID-19

People who are immunocompromised should consider a more protective face mask. Biggs suggests choosing a mask that has multiple layers or one that has a pocket where you can add a moisture barrier insert.

Older adults should also look for a high-level surgical mask that has several layers. Keep in mind, the more layers you add, the harder it is to breathe. Make sure you choose a mask that allows you to breathe but also protects you.

Don’t double mask if…

Wearing two masks could provide better protection against COVID-19, but it could also cause shortness of breath for some people, especially if your mask is too robust. In these situations, it can make breathing more restrictive and cause people to take their masks off. Biggs says it’s better to have one good mask than to wear two that restrict breathing and cause people to take their mask off.

When to toss the mask

Cloth masks should be washed every day, particularly if you are wearing them for a long period of time. If you are only wearing them for five to ten minutes, then you can go several days before washing them.

Surgical masks should be discarded every day if they are used for long periods of time. For the average person who uses surgical masks to run errands, they can be used three to four times before tossing them out. Biggs says to also keep in mind how often you are touching the outside of your mask and whether you are practicing good hand hygiene.