What are the functions of masks

Cotton masks: only provide protection against cold and warmth

The surface of the mask has large pores and cannot withstand particles with a particle size of only 2.5 microns. Some cotton masks with a filtering effect of more than 90% have very high airflow resistance, and people will have difficulty breathing after wearing them.

Ordinary gauze mask: no barrier to PM5 or less

The most common flow blocking principle of gauze masks is a mechanical barrier. Through this layer of mechanical barriers, large particles can be blocked, but particles with a diameter of less than 5 microns cannot be blocked, let alone PM2.5. particulates.

Ordinary medical masks: very useful for PM4

Medical surgical masks and medical disposable masks can block particles larger than 4 microns in diameter. According to general medical standards, for 0.3 micron particles, the permeability of medical surgical masks is 18.3%, and that of ordinary disposable medical masks is 85.6%.

Activated carbon mask: does not increase protection efficiency

Activated carbon masks can reduce some peculiar smells, but the protection efficiency of particles is not significantly enhanced. Activated carbon itself is a kind of particles, but it is a hazard for patients with chronic respiratory diseases or infirm.

N95 masks: most PM2.5 is blocked

Medical N95 masks can block the flow of large particles. When tested in the airtight laboratory of the mask, the transmission rate of medical N95 masks is only 0.425%. It can be said that more than 99% of the particles are blocked.