N95/N90 face mask is one of nine NIOSH certified particle respirators. Taking N95 mask as example, “N” means not resistant to oil. “95” means that the particle concentration in the mask is 95% lower than that outside the mask, when exposed to a specified number of special test particles. 95% is not the average filter rate, but the minimum value. N95 is not a specific product name. As long as the product meets N95 standard and passes NIOSH review, it can be called “N95 mask”. The degree of protection is N95, which means that under the test conditions specified in NIOSH standard, the filtering efficiency of the filter material of the mask for non oily particles (such as dust, acid mist, paint mist, microorganism, etc.) reaches 95%.
Except N90 and N95 face mask, we also have flat disposable face mask (surgical mask/medical mask).