The dust barrier efficiency of the medical mask is based on the barrier efficiency of its breathable dust, especially less than 2.5 microns. Because this particle size dust can directly enter the alveoli, there is a great impact on human health. Dust mask, its filtration material is an activated carbon fiber mat or a nonwoven fabric, which is less than 2.5 microns to pass the filtration material.
Many masks are arched, not only guaranteeing good fit with face, but also maintains a certain space at the mouth, wearing comfort.