The main difference between the two is where they are certified. N95 masks are approved by the NIOSH and meet U.S. standards. The CDC estimates that 60% of KN95 masks sold in the U.S. are fake.

WSJ put eight N95 and KN95 masks to the test and found not all tested at the required 95% filtration efficiency. Here are experts’ tips for spotting a lesser quality mask. Photo illustration ...

What is the difference between N95 and KN95 masks? The main differences between the N95 and KN95 masks are fit and breathability. The KN95 is required to go through a fit test, but the N95 isn’t.