Must I choose a mask with bacterial filtration efficiency (BFE) ≥95% (or 99%)?

Bacterial filtration efficiency greater than 95% is not equivalent to N95 ! This is a concept that some sellers and purchasers are confusing!

Bacterial filtration efficiency does not directly reflect the filtration capacity of droplets / droplets.

The detection of bacterial filtration efficiency is carried out with bacterial aerosol particles with an average particle diameter of about 3.0 μm, and the filtration efficiency of non-oily particles is detected with particles with a median diameter of about 0.075 μm .

●  Medical protective masks , N95 / KN95 have no requirements for bacterial filtration efficiency , but the filtration efficiency of non-oil particles is ≥95%, and the protective effect is better than medical surgical masks and disposable medical masks with bacterial filtration efficiency ≥95% .

●  In addition to bacterial filtration efficiency ≥95%, medical surgical masks also require non-oily particle filtration efficiency ≥30, so they can also play a better protective effect

●  Disposable medical masks (or other common medical masks) only meet the bacterial filtration efficiency ≥95% (or ≥99%), no requirements for particle filtration efficiency, and the protection effect is relatively poor.