The coronavirus pandemic has heralded many a cultural disruption, but perhaps none is as important–or as telling–as what we now wear: masks.
Face coverings have become a staple as essential as underwear (though there will always be naysayers–about face coverings and underwear), with the CDC recommending wearing masks in public settings as well as in private spaces shared with outsiders.
Experts say there’s evidence that, despite an Ipsos poll revealing that 77 percent of Americans wear a mask some or all of the time when leaving the house, many don’t understand the effectiveness of one face covering over another, nor why some pack the shelves while others sell out so fast they can’t be found anywhere.
One example is the N95 versus KN95 respirator conundrum.
Both are coverings reminiscent of a duckbill that press firmly against the face, unlike the relatively loose fit of a cloth face mask or bandana. But there are subtle differences between these two coverings that you should understand.
What Makes N95 and KN95 Masks Different?
“I think people are really confused about what is a respirator and what is a mask,” says Dr. Nikki McCullough, a technical and regulatory manager at 3M, the largest manufacturer of N95 respirators in the United States.
She explains that your average face mask doesn’t filter small particles while you breathe, acting instead as a “barrier” to catch large particles and droplets.
KN95s and N95s, on the other hand, are respirators. While a cloth face mask might allow some gaps–such as at the bridge of the nose or near the cheeks–respirators, McCullough says, should seal completely to the skin.
These respirators filter out 95 percent of particles that are 0.3 microns or larger in diameter, explains Dr. Michael Schivo, a pulmonologist and an associate professor of internal medicine at UC Davis Health.
“That’s important because most bacteria are larger than 0.3 microns,” he says. “Many virus particles are small, and some are smaller than 0.3 microns, but they’re suspended in water droplets that make them effectively bigger. So these masks filter out 95 percent of those small particles.”
What’s the Difference Between N95 and KN95 Masks?
The single biggest difference between the two comes down to regulation.
KN95s are typically regulated by the Chinese government, while N95s are regulated by the National Institute for Occupational Safety and Health in the U.S.
Approved KN95s will perform almost identically to N95s–they have virtually the same filtration rate and are therefore equally safe if they’re properly certified. KN95s might have ear loops; most N95s only attach via head straps. And KN95s might be more readily available for purchase as demand for N95s continues to rise.
“We started out making in the twenties of millions per month of [N95] respirators,” says Jennifer Ehrlich, a representative for 3M. “We now make more than 50 million a month. And we expect to make 95 million a month in October. That’s just in the U.S.”
Can Anyone Wear an N95 or KN95 Mask?
Respirators are currently not recommended for the general public, according to CDC guidelines.
Instead, N95s and KN95s should be directed to healthcare workers and other first responders. Why? Because they’re essential protective equipment, and as single-use products, they can run out fast.
Mark Hersam, a professor of materials science and engineering at Northwestern University, is working to change that. Through a grant from the National Science Foundation, he and his team are working to develop reusable N95 respirators that can be decontaminated with ultraviolet light.
In particular, he’s developing elastic straps that do not degrade under UV exposure. “The cloth mask definitely prevents a lot of the vapor that you exhale from spreading around a room, which is good, and that’s why everyone is encouraged to wear one,” he says. “But if you really want to capture a significant fraction of the virus particles going either way, in or out of the mask, then [N95s and KN95s] are much more effective.”
How Do You Wear a N95 or KN95 Mask?
Experts stress that both N95s and KN95s require fit-testing, unlike cloth masks. “Somebody needs to make sure you put it on properly, it’s sealed correctly, and so that it’s doing what it’s supposed to do,” says Dr. Timothy Brewer, a professor of medicine and epidemiology at UCLA.
But so long as the respirator is properly attached, there’s little reason to worry over choosing an N95 versus a KN95.