An N95 mask's material and filtration ability aren't “going to degrade unless you physically rub it or poke holes in it,”
N95 respirators protect against exposure to airborne particles.
Medical surgical masks are divided into three layers: the outer layer is a water-blocking layer (anti-adhesive non-woven fabric), which can block splashing liquid.
The production of medical masks also has requirements for the production environment.
Face masks that have not been unpacked can still be used. In fact, as long as the surgical mask, medical mask or N95 mask produced by regular manufacturers is not damaged and the mask is not contaminated
China was the first in the world to use masks. In ancient times, people in the court began to cover their mouths and noses with silk scarves in order to prevent dust and breath pollution.
