A mask brace can make your regular surgical mask almost as effective as an N95, research finds

• As new variants of the coronavirus spread, masking and distancing are more important than ever.
• Double masking may help, but mask fitters likely offer even better protection.
• Here are experts' pointers for how to know if your mask fits, protects, and seals well.

When Dr. Anthony Fauci heads to work at the White House or the National Institutes of Health, the nation's top infectious-disease expert is often sporting not one but two face masks.

He's said this double-masking strategy helps his masks fit more snugly and comfortably. But double masking hasn't been backed up by any studies or scientific recommendations.

Scientists at the Centers for Disease Control and Prevention are testing whether two masks are better than one, but they don't have enough evidence to recommend it.

In the meantime, there's one lab-tested solution that can make almost any mask more effective: the mask brace.

Also called a mask fitter, the brace goes on over a single face mask to ensure a snug, secure fit and to close any gaps where contaminated air could rush in or escape. In scientific studies from research universities around the US, it's performed nearly as well as N95s, considered gold-standard medical face masks.

Surgical and cloth masks allow particles to leak out

Mask fitters are designed to help the mask hug the contours of your face.

"These reusable devices help improve the fit of a cloth or a medical mask by creating a tight fit," Dr. John Brooks, the chief medical officer for the CDC's COVID-19 response, recently told reporters during a virtual briefing from the Infectious Diseases Society of America.

Unlike double masking, he said, "fitters have been scientifically demonstrated to improve filtration performance by as much as 90% or more, which, again, is getting into that range of filtration efficiency afforded by N95 respirators."

Fitters have been tested by independent scientists at the University of Wisconsin, the University of North Carolina, and the University of Iowa. Each institution found that they improved how well masks worked to keep your germs away from other people and to keep other people's germs away from you.

"Most masks, like surgical-style masks or just a simple knit cloth mask, they're leaking," David Rothamer, a mechanical engineer who coauthored the University of Wisconsin's recent study on mask fitters, told Insider. "Like 70% or 80% of the air is bypassing the mask."

Double masking could create more leaks if it's not done properly

Rothamer also said that double masking could, in some cases, do more harm than good.

"It's not as simple as a 'two is better than one' equation," he said. By creating more pressure between a person's face and their mask, double masking could increase leaks out of the sides and the top of the masks.

But it's hard to know whether that's the case, because there haven't been good, clear protocols established to help you know whether your mask is working well.

"I wish the government would have kind of stepped in and, at least from the mask side, given better guidance," Rothamer said. "The somewhat frustrating thing is I think there was an opportunity to say, 'OK, we can use scientists to design this, use experts, design something that's cheap to produce, do it at high quantities, and get these things out there.'"

That didn't happen. Sabrina Paseman, a former Apple engineer, created a crowdfunding campaign last spring to get the job done. Her brace is what researchers including Rothamer have used in their studies. It has also been unofficially endorsed by many leading coronavirus scientists, including Don Milton, a virus expert from the University of Maryland, and Linsey Marr, an air-quality pro from Virginia Tech.

Mask fitters can make simple medical masks nearly as effective as N95s

Paseman's company, Fix the Mask, has estimated that 30,000 of its mask fitters are in use on faces around the world. (Some of those are DIY versions from a rubber template the company shares on its website.)

"There are three things that matter with your mask: how well it filters, how breathable it is, and how well it fits," Katherine Paseman, the chief operating officer of Fix the Mask, told Insider.

To make sure your mask is breathable, put the mask on with a fitter or with your hands cupped around your nose and mouth to seal it, and ensure that you can still breathe comfortably. It may inflate a little as you're doing this test, but it should feel like air is being filtered through the mask, not escaping out the sides or the top.

Then ensure that it fits snugly and that there aren't large gaps above the mask on your cheeks or on the sides.

One way to secure the fit is to tighten the ends of your ear loops using rubber bands or rubber fasteners. But research has found that mask fitters can make your mask even more effective - closer to the effectiveness of an N95 mask.

"It's one compression-molded piece made out of silicone," Paseman said, adding that this avoids leakage so that "I know I'm actually getting the real filtration performance out of the mask."

Fix the Mask is hoping to receive certification from the National Institute for Occupational Safety and Health for its product in the coming months. That could mean it's recommended for use - along with compatible, approved masks - for millions of workers in high-risk environments across the country.

How to navigate the wild west of face masks

Whether you're double masking, using a mask brace, or doing neither, it's important to know that most masks on the market aren't rated to any uniform medical-grade standard.

"You have basically an unregulated bunch of products," Rothamer said. "Nobody really knows how they perform, unless you're someone like me who has a couple hundred thousand dollars' worth of equipment to test it."

If you want to ensure that you're wearing a mask of good filtration quality, try to find one that's ASTM-certified level one, two, or three: Level one is good enough for general use in everyday clinical settings, while level three is for filtering heavy levels of aerosols.

Whichever mask you choose, and whether you decide to double mask or not, pick a solution that you'll actually wear and feel comfortable in - one that keeps both your nose and your mouth inside.

"If we could just get people to wear masks properly, that would be a huge first step," Rothamer said. "You've got to wear the mask, and it has to fit well."

All the experts can agree on that.

"Any mask is better than no mask," Brooks said. "Regardless of what we use, it's critical that as many of us as possible mask up."