N95, N99, N100. Which is suitable for ordinary people?

N95 masks are masks that can filter pollutant particles in the air. The National Institute of Occupational Safety and Health (NIOSH) has approved 7 grades of air filter masks, including “N series”, and N95 is one of them.

N stands for Not resistant to oil, which means to protect against “non-oily airborne particles”, such as dust or droplets with bacteria and viruses. N series masks are divided into 3 grades according to their filtration efficiency: N95 grade, with a minimum filtration efficiency of 95%; N99 grade, with a minimum filtration efficiency of 99%; N100 grade, with a minimum filtration efficiency of 99.97%.

For example, if there are 100 suspended particles in the air, N95 means that only 5 particles will pass through the mask. In contrast, N99 and N100 masks have better filtering effects. But at the same time, the last two types of masks have greater respiratory impedance, which makes it easier for people to feel breathing difficulties and the masks cannot be worn. Therefore, only a few professionally necessary personnel can use them.