Filtration efficiency: Under the condition of air flow (30 ± 2) L / min, the filtration efficiency of aerodynamic median diameter (0.24 ± 0.06) μm sodium chloride aerosol is not less than 30%. Bacterial filtration efficiency: Under specified conditions, the filtration efficiency of aerosols of Staphylococcus aureus with an average particle diameter of (3 ± 0.3) μm is not less than 95%; the filtration rate of bacteria should be ≥95%; Should be ≥30%.
Breathing resistance: Under the condition of filtration efficiency flow, the inhalation resistance does not exceed 49Pa, and the exhalation resistance does not exceed 29.4Pa. When the pressure difference △ P of gas exchange on both sides of the mask is 49Pa / cm, the gas flow rate should be ≥ 264mm / s.
Nose clips and mask straps: Nose clips should be provided on the mask. The nose clips are made of plastic materials and the length of the nose clip should be greater than 8.0cm. The mask band should be easy to wear and take, and the breaking strength at the connection point between each mask band and the mask body should be greater than 10N.
Synthetic blood penetration: After 2ml of synthetic blood is sprayed at the pressure of 16.0kPa (120mmHg) towards the outer side of the mask, no penetration should occur on the inner side of the mask. Flame retardant performance: The mask material should be made of non-flammable materials, and the mask burns less than 5s after leaving the flame.
Residual amount of ethylene oxide: For masks sterilized by ethylene oxide, the residual amount of ethylene oxide should be less than 10 μg / g. Skin irritation: The primary irritation index of the mask material should be ≤0.4, and there should be no sensitization. Microbial indicators: total bacterial colonies ≤20CFU / g, no coliform bacteria, Pseudomonas aeruginosa, Staphylococcus aureus, hemolytic streptococci and fungi can be detected