The situation of disease outbreak due to new strain of Corona family (nCoV) is increasingly complicated. Preventive measures are very important in that the proper use of masks is an important measure for each person to protect themselves and contribute to fighting the disease.
Facing the community rushing to buy masks, the Health Ministry of several countries has made the following recommendations:

People who have a fever, cough or runny nose or who are recovering should wear a mask as this is a good way to prevent spreading germs to others.
– Healthy people do not need to wear masks, unless they are in direct contact with the sick person, especially those who are coughing / sneezing without wearing a mask.
– Also, consider wearing a mask when going into a crowded place, in a closed room because you do not anticipate the risk of infection in that environment.
The Vietnamese market currently has a variety of masks with different designs, but in the prevention of respiratory infections, there are two types of official masks.

The first type is a medical mask / surgical mask with 3 layers, the outer layer is usually green or yellow. The Vietnam Institute of Applied Medicine adds that ordinary medical masks have 3 layers with different uses
The outer layer has waterproof properties, effectively preventing the liquid particles from splashing out when the patient sneezes, coughs, breathes hard … The outside surface is usually light blue to distinguish easily, wear a mask It is true that the color layer will turn out.

The inner layer is always white, very easy to distinguish from the outer layer. The face of the cloth turns inwards, close to the skin of the face, so it must be pure and smooth, without fiber fibers causing discomfort. In addition, it must be waterproof to sweat to create comfort for the user.

The middle layer prevents particles from splashing and must filter dust and bacteria. This is the layer that determines the quality of the mask. A “right” filter layer must allow air to pass easily, creating a sense of ventilation for users, but must have a structure sufficient to filter out particles of microscopic dust and bacteria.