Medical masks are one of the important materials for the prevention and control of the new coronavirus pneumonia epidemic. They are an important line of defense against respiratory infectious diseases and can reduce the risk of new coronavirus infection. Medical-grade face masks can not only prevent patients from spraying droplets, reduce the amount and speed of droplets, but also block virus-containing droplet nuclei to prevent the wearer from inhaling.
Ⅰ. Medical-grade face masks are classified according to the form of the cover
Usually there are straps, head-mounted, ear-hook and so on. The strap type and head-mounted type medical-grade face masks are suitable for medical staff who wear it for a long time. It is troublesome to wear, but has no burden on the ears; ear-mounted type: easy to wear, suitable for frequent wearing and taking.
Ⅱ. Medical grade masks are classified according to the shape of the mask
Flat, folded, duckbill, fish and arched, etc. Flat masks are easy to carry, but have poor tightness; foldable, duckbill, and fish-shaped masks are easy to carry; arched breathing space is large, and the tightness is good, but it is not convenient to carry.
Ⅲ. Medical grade masks are classified according to the implementation standards
1. Disposable medical masks
Disposable medical masks implement recommended industry standards, which are applicable to disposable masks that cover the user's mouth, nose and jaw, and are used in ordinary medical environments to block exhaled or exhaled pollutants from the oral and nasal cavities. The main performance indicators of breathable medical face masks include bacterial filtration efficiency, ventilation resistance, microbial indicators, ethylene oxide residues, biological evaluation, etc. The filtration efficiency of bacteria should not be less than 95%. A typical disposable medical mask structure is an ear-hook type.
2. Medical surgical masks
Medical surgical masks implement mandatory industry standards, which are applicable to disposable masks worn by clinical medical staff during invasive operations and other processes. The main technical indicators include filtration efficiency, pressure difference, microbial indicators, ethylene oxide residue, biological evaluation, synthetic blood penetration, flame retardant performance, etc. The filtration efficiency of non-oily particles is not less than 30%, and the bacterial filtration efficiency is not less than 30%. Not less than 95%. A typical medical surgical mask structure is an ear-hook or strap-type plane.
3. Medical protective masks
Medical protective masks implement mandatory national standards, which are suitable for self-priming filtering medical protective masks that filter particulate matter in the air and block droplets, blood, body fluids, secretions, etc. in medical environments. The main technical indicators of protective medical-grade masks include filtration efficiency, airflow resistance, microbial indicators, ethylene oxide residue, biological evaluation, synthetic blood penetration, flame retardant performance, surface moisture resistance, adhesion, etc. The filtration efficiency grade of particles is divided into grade 1 (≥95%), grade 2 (≥99%), and grade 3 (≥99.97%). Typical medical protective masks are folded or arched.
Medical-grade face masks can be divided into two types: non-sterile and sterile according to the microbial status of the product. Non-sterile masks should meet microbial control standards, that is, a certain amount of microorganisms are allowed, but they must be within a controllable range, and there is no related pathogenic bacteria. The sterile mask is guaranteed to be sterile within the validity period after the corresponding sterilization process.