The breathing valve in N95 mask is mainly to make the human body more comfortable and can help the exhaled air out of the mask quickly. At this time, it is suitable to use the N95 mask with the breathing valve in some hot and humid or poor ventilation, or large labor environments.

The principle of the respiration valve, the positive pressure of the gas is the time to exhale, which will blow the valve open, mask of exhaust fumes can quickly, reduce the sticky feeling when using a mask, and breathing under negative pressure can make the valve automatically shut down, can avoid the absorption into the external environment of the pollutants, so can make human body at the time of use is more comfortable.