Performance standards of medical protective masks

Medical protective masks are suitable for the protection of airborne respiratory tract infectious diseases by medical staff and related staff. It is a close-fitting self-priming filter medical protection article with a high protection level, especially suitable for contact with airborne transmission during diagnosis and treatment activities. Or worn by patients with respiratory infections transmitted by droplets at close range. It can filter the particles in the air, block droplets, blood, body fluids, secretion droplets, etc. It is a disposable product. Medical protective masks can prevent most pathogens such as bacteria and viruses. WHO recommends medical personnel to use protective masks against particles to prevent viral infections in hospital air.

Medical protective masks comply with GB19083-2003 "Technical Requirements for Medical Protective Masks". Important technical indicators include non-oily particle filtration efficiency and airflow resistance. The specific indicators are as follows: Filtration efficiency: Under the condition of air flow (85 ± 2) L / min, the filtration efficiency of aerodynamic median diameter (0.24 ± 0.06) μm sodium chloride aerosol is not less than 95%, which is in line with N95 (or FFP2) and above. It can block infectious agents with a diameter of less than 5 μm transmitted by air or close contact with infectious agents transmitted by droplets.

Inhalation resistance: Under the above flow conditions, the inhalation resistance does not exceed 343.2Pa (35mmH2O). For the samples sprayed on the mask under the pressure of 10.9Kpa (80mmHg), no technical indicators such as penetration should appear on the inside of the mask. The nose mask must be equipped with a nose clip, which is made of a bendable plastic material and has a length of> 8.5cm. Synthetic blood is sprayed towards the mask sample at a pressure of 10.7 kPa (80 mmHg), and there should be no penetration inside the mask.