N95 vs. KN95 masks: What’s the difference?

COLORADO SPRINGS, Colo. (KRDO) - The terms N95 and KN95 for masks have been used interchangeably by many since the pandemic began in 2020. But there's a reason for the K, and the difference has to do with who's regulating the mask you wear.

"N95 refers to a NIOSH-approved filtering respirator or face mask," said Dr. Chris Urbina, Interim Medical Director for El Paso County Public Health. "NIOSH stands for the National Institute for Occupational Safety and Health. N95s have been used primarily by healthcare workers to filter and protect themselves from a horrible variety of infections, not just COVID 19, but tuberculosis, any infection that might be spread respiratory."

K95 masks are not approved by NIOSH. They typically meet international standards, according to the Centers for Disease Control and Prevention.

“The CDC has pointed out their concerns that the quality control of the KN95 is not of the same level of quality as the N95," said Dr. William Plauth, Chief Medial Officer for Penrose-St. Francis Hospital. "A frequently-cited study shows that in 2020 and 2021, as many as 60 percent of the KN95s did not meet their stated goal.”

However, that doesn't mean KN95s don't offer strong protection against Covid-19.

"The N95 and KN95 have the same goal of filtering down 95 percent of very small particles that are most likely to transmit disease," said Dr. Plauth.

The most important feature of a mask is how well it fits on your face, without gaps. If a KN95 is snug on your face, it likely is offering great protection.

"Early on in the pandemic, we had very little N95 masks and we were trying to reserve those for health care workers," said. Dr. Urbina. "Now we have a slew of them, which is great. So it doesn't matter which one you use, as long as they fit snugly enough to allow or decrease the amount of respiratory aerosolization or as well as droplet spread."

The CDC has recently announced "loosely woven cloth products provide the least protection" against Covid-19 and encourages Americans to wear other options like surgical masks, N95s, and KN95s.

"Let's talk about the quality of those masks," said Dr. Urbina. "The N95 and K95 have multiple filters, usually three to five layers of protection. So that allows [fewer] droplets to be spread. Cloth masks as you know, you can actually sneeze through a cloth mask, so they don't have the same kind of filtration."

Dr. Urbina says if you have a lot of cloth masks at home or in your car collecting dust, a great use for them is to layer the masks on top of surgical masks.

"The message is: wear a mask, and if you don't have access to that N95, wearing a surgical mask with a cloth mask on top of it actually makes it snugger on your face," said Dr. Urbina. "You can stop the air from going outside, above your nose, and around your cheeks by adding another cloth mask."

KN95s are readily available to buy since they don’t have to undergo rigorous approval, so be smart when shopping online.

"The main thing is, just make sure to look up on the site that you're getting it from, that it's a reputable manufacturer," said Dr. Plauth. "If you have the opportunity to get an N95, I would preferentially get that over a KN95. But a well-made N95 should be just as good."

"The problem with buying online, is you can't tell if it fits your face until you actually get the product," said Dr. Urbina.

If you're confused whether you've bought an N95 or KN95, it's easy to find out.

"It's actually written on the the mask itself, it'll say an N95 NIOSH approved, or KN95,” said Dr. Urbina.