for children are white, and there are many types on the market: the first type is medical white masks. One of the tricks to distinguish the front and back is to look at the ears first, if the ears have obvious fit. , It means that this is the reverse side; another way to judge is to look at the nasal patch of the mask. If the nasal patch is more obvious, it means it is on the inside, and the smooth side is on the outside.
No matter what is white or colored, wear it on the outside with the folds facing down! The thread ends are more reliable than looking at the connection!
The white mask is really difficult to distinguish, but we can easily distinguish the front and back through the two items of crease and thread.
1. Differentiation of creases
The side with the crease upward is the inner face, and vice versa is the outer face
In addition, I also found a picture from the Chinese Medicine Fangnet. It can be seen that the mask worn by this doctor is on the outside with the crease downwards:
The side with the thread is the outside, and vice versa, the side without the thread is the opposite.
Metal strip distinction
Generally, the side of the metal strip that is above and protruding to the outside is the outside, and the opposite side is on the inside.
According to the degree of smoothness, the outer part of the mask is mostly smooth because it has a water blocking function; while the inner part is mostly made of a material with good air permeability, which is close to the skin and facilitates breathing.