However, public health officials continue to emphasize that N95 masks and surgical masks should be reserved for first-line doctors and nurses in urgent need of protective equipment.
With the outbreak of new coronary pneumonia in the world, many countries attach great importance to the problem of wearing a mask, because wearing a mask is not only a personal hygiene problem, but also to prevent the virus from spreading each other.
Door-to-door pickup has become a new way for countries to protect mask supplies.
Why should we correctly distinguish the front and back of the mask?
