This article explains the difference between ordinary civilians and medical masks, and how to choose reliable medical masks.
Masks are mainly composed of a three-layer structure. The melt-blown non-woven fabric in the middle is the core part. It has the function of preventing dust, droplets, bacteria and viruses, and other pathogenic microorganisms. It can be divided into ordinary civilian, medical or surgical grades.
The ordinary civilian grade is also called Disposable Face Mask. The melt blown cloth used in the middle layer is an ordinary melt-blown cloth that has not undergone polarization treatment to add electric charges. The pore size of this kind of meltblown cloth is generally between a few microns to more than ten microns, and the large droplets have a diameter of 100 microns; if they lose moisture in the air, they can quickly be reduced to less than 1 micron, so it only has the effect of blocking large droplets. There is no electrostatic adsorption effect. When inhaling, bacteria and viruses will enter the body with the air pressure difference, and the protective effect can be imagined. When the supply of melt-blown cloth was tight, many small workshops' non-compliant melt-blown cloth flowed into the civilian mask market.
Disposable Medical Mask or Disposable Surgical Mask uses a polarized meltblown cloth to make the meltblown cloth charged with static electricity and maintain this state for a long time. Even if the particles in the air are smaller than the pore size of the meltblown cloth, they will be attracted by the increased static electricity when they pass through the mask due to the strong adsorption force of the surface of the meltblown cloth. Medical masks must also meet other strict protection standards, such as bacterial filtration efficiency (BFE) must be more than 95%, and some can reach 99%. In addition, the waterproof and airtight performance is relatively good, which can be used by hospital staff as well as ordinary people.
The wearing time of a medical mask is generally four hours, and it is recommended to replace it after four hours of use. Once saliva splashes are contaminated, it must be replaced immediately. Masks should not be reused, because breathing moisture will reduce the electrostatic adsorption effect of the meltblown cloth and reduce the barrier effect of bacteria and viruses. If you have a choice, it is recommended that you try not to use washable traditional textile cloth masks, because cloth masks have larger fiber pores.
China's medical device production license or medical device registration certificate is a reliable qualification certificate because to obtain this certificate, it must go through the on-site inspection of the production environment by the China National Medical Products Administration and strict testing by third-party agencies; a large number of products will be converted after the epidemic Non-compliant manufacturers of masks are usually not available.
China Customs also currently stipulates that masks produced by manufacturers without a medical device production license or medical device registration certificate cannot be exported. Therefore, it is recommended to look for the words "Medical" or "Surgical" (Medical or Surgical) masks on the packaging box. If you can afford it or go to a crowded place, try to choose a regular medical mask.