What is the specific standard for N95 masks?
2022-02-06
"N" means "not resistant to oil". "95" means that the particle concentration inside the mask is 95% lower than the particle concentration outside the mask when exposed to the specified number of special test particles. Among them, the value of 95% is not the average value, but the minimum value, so the average value of actual products is mostly set above 99%.
Other anti-particulate mask levels certified by NIOSH include: N99, N100, R95, R99, R100, P95, P99, P100, these protection levels can cover the protection range of N95, where "R" means, suitable for oily or non-oily Particulate, if used for oily particulate protection, the use time should not exceed 8 hours; "P" means, suitable for oily or non-oily particulates, if used for oily particulates, the use time should follow the manufacturer's recommendations. And "99" and "100" refer to the filtration efficiency level, respectively.
It is divided into "N", "R", and "P" according to oil resistance, and "95", "99" and "100" according to the capture rate. "R" means "resistant to oil", "P" means "oilproof", "99" in the catch rate means more than 99%, and "100" means more than 99.7%.
In addition, when N100, P100, and R100 three-type masks are tested with 0.3 micron particles, the barrier efficiency must reach more than 99.7%. above 95%.
Therefore, N95 masks are tested with 0.3 micron sodium chloride particles, and the barrier rate must be more than 95%. When the wearer's face is tested for tightness, it is ensured that the air can enter and exit through the mask when it is close to the edge of the face. Only those who meet this test are issued an N95 certification number.
At present, there is a certain gap between the testing methods of domestic protective masks and foreign testing methods. Generally speaking, protective masks that have passed the existing domestic standard certification cannot yet reach the N95 level standard.
