How can you spot a counterfeit N95 or KN95 face mask?

The CDC says about 60% of the KN95s it evaluated in 2020 and 2021 were counterfeit: That is, the items did not work as they were supposed to. Fake N95s, meanwhile, are so prevalent CDC has published

As for KN95: That's an international designation, and, per the CDC, filtration standards may vary. There is no KN95 on the market that's been officially graded by a U.S. agency

NIOSH markings on KN95s. This is an obvious sign of a counterfeit because, as discussed, the NIOSH has not certified any KN95s

Respirators bedecked in sequins or other "decorative fabric." Real N95s are all business

Respirators that you loop around your ears (surgical masks) instead of around your head, à la genuine N95s

The CDC's page on counterfeit respirators is a great resource, and contains examples (and pictures!) of N95s and KN95s that the agency has flagged

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