N95 mask refers to a mask with a protection efficiency of not less than 95% for non-oily particles certified by the United States NIOSH (National Institute of Occupational Safety and Health).
The N95 mask is one of the nine anti-particulate masks certified by NIOSH (National Institute of Occupational Safety and Health). "N" means that it is used to protect non-oily particles (such as viruses, bacteria, dust, etc.); "95" means that the filtration efficiency of the mask is ≥95% under the testing conditions specified by the standard. N95 mask can effectively protect the particles suspended in the air.
Why can I wear N95 masks during the new coronavirus epidemic?
1. The spread of the new coronavirus requires a host vector. Once it leaves the body of the host (such as animals, humans), it will die in a short time, but the virus can be spread through contact (such as hand pollution), droplets, etc., among which coughing, In speech, droplets produced when sneezing are the main carriers of transmission. If a new coronavirus carrier sneezes in a confined space (such as a train or airplane, etc.), the dropped droplets are easily inhaled by another person and may be infected. Therefore, it is necessary to wear a mask for protection.
2. Since the virus and its transmission medium (droplets) also exist in the form of particles, and the diameter of the particles is relatively small, the N95 mask filtering mechanism is to filter these fine particles through the high-performance filter material in the mask. The efficiency test method uniformly uses particles with an aerodynamic diameter of 0.3 microns, which is the most difficult to filter among the diameters of particles with a known normal distribution. At the same time, N95 masks also have strict requirements for their tightness. Therefore, the correct wearing of N95 masks can reduce the exposure to pathogenic microorganisms in the air and effectively prevent viruses from entering the human body from the respiratory tract. However, the wearer should also pay attention to the prevention of hands, eyes, etc., so as not to be infected through other means.
How often do I replace N95 masks?
Under normal circumstances, if it is used outdoors, such as subways, buses, supermarkets, shopping malls and other public places, N95 masks need to be replaced every 4-6 hours, but if it is in a new pneumonia virus-affected area, it is recommended to be in time in 2 hours Replace the N95 mask once.