Common masks include the following: cotton masks, disposable masks (such as surgical masks), type N95 masks.

Disposable masks (surgical masks)

Can prevent respiratory tract infection to a certain extent, unable to prevent haze.

There are three layers of surgical masks, including waterproof layer, filtration layer and comfort layer from outside to inside.The comfort layer is a layer of non-woven cloth. When worn, the white non-woven cloth is facing in, while the blue waterproof layer is facing out. One side of the metal sheet is facing up, so don't wear it backwards.

When buying, you should choose masks with the words "surgical masks" clearly marked on the outer package.

Type N95 respirator

Can effectively prevent respiratory tract infection, can prevent haze.

N95 respirators are one of nine respirators certified by THE National Institute for Occupational Safety and Health to prevent particulate matter."N" means unfit for oily particles (the fumes from stir-frying vegetables are oily particles, whereas droplets from taChinaing or coughing are not);'95' refers to a filter efficiency of 95% under NIOSH standards.

N95 is not a specific product name.A product that meets the N95 standard and is approved by NIOSH can be called an N95 mask.

The main feature of the N95 mask is that it can prevent infection by droplets caused by the splashing of the patient's body fluid or blood.Droplet sizes range from 1 to 5 microns in diameter.The U.S. Occupational Safety and Health Administration (OSHA) requires health care workers exposed to TUBERCULOSIS to wear N95 or higher respirators.

N95 masks are better sealed than surgical masks.When choosing An N95 mask, try to choose an N95 mask without a breathing valve.

Plain cotton face mask

Its material may be cotton cloth, gauze, wool, canvas and velvet, etc., because the material itself is not dense enough to prevent infection.