1.
Medical surgical masks are divided into three layers: the outer layer is a water-blocking layer (anti-adhesive non-woven fabric), which can block splashing liquid; the middle layer is a filter layer (melt-blown non-woven fabric), which can effectively block particles from 0.3 to 1.0 pm ; The inner layer is a water-absorbing layer (anti-adhesive non-woven fabric), which can absorb moisture in the wearer's mouth and nose. It must also be equipped with a nose clip and lace.
It should be noted that the electret-treated meltblown cloth in the middle layer is commonly known as the "heart" of the mask. When the virus-containing droplets approach the meltblown cloth, the droplets will be blocked, and the virus will be electrostatically adsorbed on the fiber surface and cannot pass. Can play a role in blocking the spread of the virus. And the meltblown cloth must reach a certain weight to reach the standard, generally 20g.
2. The quality of the meltblown fabric in the middle layer of disposable medical masks is poor or has no meltblown layer, and some have not undergone electret treatment, which has much poorer virus barrier effect and medical surgery.
3. Non-medical disposable/protective masks. At present, most of the products on e-commerce have three layers, and they also use meltblown cloth. Some also say that the meltblown layer of their masks is n95 medical Level. But whether it is melt blown cloth or not, even if it can meet the standard, whether the weight is enough, it depends on the conscience of the business. Because there is no national level supervision, it is difficult to judge whether it is comparable to the medical level. But don’t see that there is no non-medical product, just think it is a three-no product. After all, certain conditions are required for manufacturers to obtain the qualification to produce masks. Masks of this level can still be used in some low-risk situations.
