1. Diffusion deposition: Brownian motion of particles diffuses and shifts to filter fibers, and is adsorbed by molecular gravity. It is easy to capture small-scale particles, fine fibers and low-speed moving particles.
The smaller the particles, the stronger the deposition effect of 1, 4, and the larger the particles, the better the effects of 2, 3, so the smaller the particles, the more difficult it is to filter. Synergistic effects of various filtration mechanisms, the easy-penetrating particle size range of ordinary mechanical filter media is 0.1m～0.3m.
Main filter material: such as polypropylene melt blown cloth, etc. Other materials: metal (used for nose clips), dyes, elastic materials (used for mask straps), etc.
According to the shape of the mask, it can be divided into flat shape, duckbill shape, arch shape or folding type. According to the wearing style, it can be divided into ear-hook style, strap style or headband style.