The function of the front and back of the mask is different. Many masks use a three-layer design type, in which the filter layer for filtering bacteria is located in the middle, the outer layer is a waterproof layer, and the inside is a water-absorbing layer. If it is worn backwards, the water-absorbing layer will become a waterproof layer, and the waterproof layer will become a water-absorbing layer, which will cause the saliva to adhere to the surface of the mask, and the more it accumulates, the more the mask may get wet and the mask will lose its filtering function.
How do you distinguish the front and back of the mask?
Judging by the appearance
Generally, we see a blue medical surgical mask, the blue side is the outside, and the light-colored (white) side is the inside (attached to the face). Other colored masks can also be judged according to this principle. If the mask or brand name is printed on the mask, the side with the logo or embossing is the outside.
Judging by the direction of the fold
Judging by the fabric material
The inner side of the mask is a water-absorbing layer, the fabric is softer, the outer side is a waterproof surface, and the fabric is stiffer than the inner side. With a drop of water, the hydrophilic side (water will infiltrate the surface) is facing inwards, and the hydrophobic side (water is not infiltrating and spherical) facing outwards.