1. Prevent the virus from invading
The air is mixed with a lot of dust, bacteria, viruses and a variety of harmful gases, they may breathe into the nose, pharynx, trachea, lungs. When the body resistance is weak, people sick, and wear a mask, as if to the respiratory tract set up a "barrier." So that the inhalation of air play a filtering effect.
2. to prevent the virus out
Wearing a mask also blocked their own nose and mouth bacteria because of speech, cough, sneezing and infected with other people. Such as the SARS period, we all national wear masks, as is to prevent the spread of respiratory diseases. The same time as the above-
3. Avoid cold air stimulation
Cold air will directly stimulate the baby's nasal mucosa, causing allergic reactions, masks can play a warm role.