What's the difference between N95, KN95, KF94 and surgical masks?

Oct 19, 2023

View from above of N95, KN95, surgical, and homemade protective face masks.

Deep into 2022, wearing masks in public began to feel like a bygone practice of the COVID-19 pandemic — not entirely gone, but more of an optional precaution. With the three-pronged rise in transmissions of COVID, flu and respiratory syncytial virus (RSV) late in the year, however, the need for masking has reappeared, right as peak holiday travel approaches.

Even since mask mandate enforcement stopped in April, the Centers for Disease Control and Prevention has continued to recommend "properly wearing a high-quality mask or respirator over the nose and mouth in indoor areas of public transportation (such as airplanes, trains, buses, ferries) and transportation hubs (such as airports, stations, and seaports)."

While 2021 was about preventing the spread of COVID, and 2022 is about preventing the spread of three different viruses, the guidance on masking hasn't changed: "The point of masks is to block respiratory droplets and aerosols containing viral particles," according to the National Institute of Health. More importantly, "the masks are agnostic as to what virus is in the particles."

It's important to understand what designations such as "N95" and "KN95" mean when it comes to masks and the level of protection those designations offer, versus, say, a cloth mask made at home. Choosing the right mask this winter could spell the difference between spreading holiday cheer alone or simultaneously spreading a potentially deadly virus, too.

Honeywell Safety NIOSH-Approved N95, 20-pack

"N95" is a certification provided by the National Institute for Occupational Safety and Health, an agency within the CDC. According to the CDC, N95 masks are "the most common of the seven types of particulate filtering facepiece respirators." The "95" refers to the fact that they filter out 95% of airborne particles. In order to fit properly, N95s require an elaborate "fit test," where the wearer moves their head around and tries to detect a bitter odor.

In January 2021, former CDC Director and CEO of Resolve to Save Lives Dr. Tom Frieden tweeted that N95s are "the most protective mask."

For most of the pandemic, the CDC recommended laypeople not wear N95 masks so as to reserve them for healthcare and frontline workers amid production shortages. But as of August 2022, the Food and Drug Administration removed N95s from its device shortage list as supply chains met demand. Supplies of N95 masks are available at Amazon, Walmart and Home Depot, among others.

WWDOLL KN95 Face Mask 25 Pack

KN95 is a safety qualification in China, and KF94 is a qualification in South Korea, for the standards those countries use to determine the effectiveness of face masks.

These standards are generally considered to be less stringent than those enforced by NIOSH, but the CDC does keep a whitelist of manufacturers whose KN95 masks passed an N95 qualification test, though these masks do not receive the N95 qualification. One of the main differentiators between these masks and N95s are the presence of ear loops, as opposed to the dual head straps required for an N95.

Powecom KN95 Face Mask 10-pack

EN149 is the European standard of testing face masks, and it sorts masks into three categories of Filtering Face Piece (FFP):

3 Ply Black Disposable Face Mask (100 count)

While less convenient or stylish than cloth face masks, the 3-ply surgical masks’ three layers are better than traditional cloth masks due to the non-woven materials, which are more effective at blocking particles than most ordinary cotton.

Of course, since there is so much variety in how unregulated cloth masks are manufactured, it's more difficult to be definitive on the efficacy of masks at this level.

In 2021, there was some speculation that neck gaiters were worse than not wearing a mask at all. This, along with the reports that cloth masks may not be effective enough to stop the spread of the pandemic, led some to conclude that cloth masks don't work at all.

But, as the CDC says, "any mask is better than no mask." If you can't get an N95 or KN95 in time for travel, consider a double-layer mask. Whichever you choose is a simple solution to protect you and your loved ones — and the choice is yours.