Speaking of the shell mask, everyone should be familiar with it. Now the medical staff needs to wear it when performing surgery or dressing change, but there are often some misunderstandings when using medical surgical masks, so the disposable mask is small. Edited to give a simple introduction to the majority of users.
Medical surgical masks must comply with YY 0469-2004 "Technical Requirements for Medical Surgical Masks". Important technical indicators include filtration efficiency, bacterial filtration efficiency and respiratory resistance:
1. Filtration efficiency: under the condition of air flow rate (30±2) L/min, the filtration efficiency of aerodynamic median diameter (0.24±0.06) μm sodium chloride aerosol is not less than 30%;
2. Bacterial filtration efficiency: under the specified conditions, the average particle diameter of (3 ± 0.3) μm of Staphylococcus aureus aerosol filtration efficiency of not less than 95%;
3. Respiratory resistance: Under the condition of filtration efficiency flow rate, the inspiratory resistance does not exceed 49Pa, and the expiratory resistance does not exceed 29.4Pa.