The two are the same, there is no difference.
KN95 is one of the levels specified in the Chinese standard GB2626-2006. N95 is one of the levels specified in the American standard 42CFR84. The technical requirements and test methods of these two levels are basically the same, and the filtration efficiency reaches 95% under the corresponding standards.
N95 masks actually belong to respirators. Respirators are a kind of respiratory protection equipment. Compared with ordinary masks, they fit the face tighter in design, and can filter particles in the air very effectively.
Among them, N means Not resistant to oil, which can be used to protect non-oily suspended particles; 95 means that the filtration efficiency is greater than or equal to 95%, indicating that after careful testing, this respirator can block at least 95% of very small (0.3 Micron level) test particles.
In terms of design, if ranked according to the priority of the wearer’s own protection capabilities (from high to low): N95 mask>surgical mask>ordinary medical mask>ordinary cotton mask. If worn correctly, the filtering capacity of N95 is better than ordinary masks and medical masks. However, even if it is worn in full compliance with the requirements, the risk of infection or death cannot be eliminated 100%.