2, medical masks. There are two kinds sold in general pharmacies: non-woven disposable medical masks, and gauze masks, usually around one in 3 yuan. Citizens who are sensitive to climate change can choose to wear disposable medical surgical masks or gauze masks with more than 12 layers. It should be noted that the sterilization grade and ordinary grade marked on the outer packaging of medical care masks refer to the cleanliness of the masks themselves, and have nothing to do with the filtering effect. When choosing, you can look for the "Drug Administration Machinery Standard".
3. Activated carbon mask. Drugstores, convenience stores and online stores all sell this kind of masks. Depending on the quality of activated carbon in the masks, the price ranges from 20-60 yuan/pack, with 50 pieces in a pack. It can also be sold individually, but generally, most people buy a whole package now because of the rapid upgrading.
4.N95 mask. N95 mask is a professional dust mask. Ordinary pharmacies generally don't sell N95 and N90 masks, and hospitals don't take them out, let alone ordinary patients. People need to go to pharmaceutical companies to buy. Experts advise ordinary citizens not to blindly wear professional protective masks. Wearing this professional protective mask requires training. If you don't know this knowledge, you'd better not wear it at will.