The main technical indexes are as follows: (1) filtration efficiency: under the condition of air flow rate of (30 ± 2) l / min, the filtration efficiency of sodium chloride aerosol with aerodynamic median diameter of (0.24 ± 0.06) μ m is no less than 30%; (2) Bacterial filtration efficiency: under the specified conditions, the filtration efficiency of Staphylococcus aureus atcc6538 should not be less than 95%; (3) pressure difference: under the specified conditions, the pressure difference between the two sides of the mask for gas exchange should not be greater than 49pa; (4) Penetration of synthetic blood: after 2ml of synthetic blood is sprayed at the pressure of 16.0kpa (120mmhg) to the outer side of the mask, there should be no penetration on the inner surface of the mask. It is used to wear on the mouth and nose of medical staff in the operating room to prevent dandruff and respiratory tract microorganisms from spreading to the open surgical wound surface, and prevent the body fluid of surgical patients from spreading to the medical staff, so as to play the role of two-way biological protection. Proper wearing of masks is an effective way to block the transmission of respiratory secretions. Medical surgical masks can prevent the spread of respiratory infectious diseases. The wearing methods are as follows: (1) before wearing the mask, hands should be cleaned to avoid touching the inner side of the mask to reduce the possibility of contamination; (2) when wearing the mask, distinguish the inside and outside, up and down of the mask, the light color side is inside, the dark side is outward, one end of the metal strip (nose clip) is above the mask, and the folding surface is fully unfolded; (3) Clamp the two ends of the bandage to the upper and lower ends of the nose band, and then fasten the bandage to the lower end of the nose band or the lower end of the nose band. (1) When purchasing and using medical surgical masks, you should purchase them in regular hospitals and pharmacies. At the same time, pay attention to the production batch number, production date and service life of the product's outer packaging. Production license, product registration number and other information, as well as detailed product instructions; (2) before use, please check whether the package is in good condition, confirm the external packaging mark, production date and validity period, and use it within the sterilization validity period; (3) ensure that the mask covers the nose bridge to the mandible after unfolding, so as to obtain the expected protective effect; (4) Disposable medical surgical masks are prohibited to be reused; (5) medical surgical masks should not be used if the package is damaged before use; (6) use with caution for those allergic to nonwovens; (7) medical surgical masks should be treated according to the requirements of the hospital and environmental protection department.