The new coronavirus is transmitted through droplets, and the particles of droplets are still larger, because they carry water molecules, so general masks can also prevent the new coronavirus, but the problem of efficiency, KN90 and KN95 are mainly efficient when preventing particles below 0.3 microns, KN95 can prevent more than 95%, KN90 can prevent more than 90%. Medical personnel who rush to the front line should be given the best protection, so the use of N95 is best. But when the normal human life environment or ordinary contact, even ordinary medical masks can be. Content source: Dr. You Lai