The medical mask consists of a mask body and a tension band. The mask body is divided into three layers: the inner layer is made of skin-friendly materials (ordinary sanitary gauze or non-woven fabric), the middle layer is made of isolation filter layer (ultra-fine polypropylene melt-blown material layer), and the outer layer is made of special material antibacterial layer (non-woven fabric or ultra-thin polypropylene melt-blown material layer). [ 1]
classify
According to the performance characteristics and scope of application, medical masks can be divided into: medical protective masks, medical surgical masks and ordinary medical masks.
1. Medical protective mask
Medical protective masks are suitable for medical staff and related staff to protect against airborne respiratory infectious diseases. It is a self-priming and filtering medical protective article with high protection level, which is especially suitable for patients who are in close contact with respiratory infectious diseases spread by air or droplets in medical activities. It can filter particles in the air and block droplets of blood, body fluids, secretions, etc. It is a disposable product. Medical protective masks can prevent most pathogens such as bacteria and viruses. WHO advises medical staff to wear protective masks against particles to prevent virus infection in hospital air. [2]
The medical protective mask conforms to GB 19083-2003 Technical Requirements for Medical Protective Masks, and its important technical indicators include filtration efficiency of non-oily particles and airflow resistance. Specific indicators are as follows: [3]
1) filtration efficiency: under the condition of air velocity of (85 2) l/min, the filtration efficiency of sodium chloride aerosol with aerodynamic median diameter of (0.24 0.06) micron is not less than 95%, that is, it meets the grade of n 95 (or FFP2) and above. Diameter that will hinder air transmission