Medical surgical masks are generally made of three layers of non-woven fabrics. The material of the three-layer non-woven fabric is spun-bonded non-woven fabric + melt-blown non-woven fabric + spun-bonded non-woven fabric. You can also use a layer of staple fiber to improve skin feel, that is, ES hot-rolled nonwoven fabric + meltblown nonwoven fabric + spunbond nonwoven fabric. The outer layer of the mask has anti-spray design, the middle layer filters, and the memory absorbs moisture. Meltblown cloth is generally selected to weigh 20 grams.
The national YY0469-2004 “Technical Requirements for Medical Surgical Masks” standard stipulates that important technical indicators that medical surgical masks must achieve include filtration efficiency, bacterial filtration efficiency and respiratory resistance: 1. Filtration efficiency: at air flow (30 ± 2) L / min Under the conditions, 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 is ) The filtration efficiency of μm Staphylococcus aureus aerosol is not less than 95%; 3. Respiratory resistance: under the condition of filtration efficiency flow rate, the inhalation resistance does not exceed 49Pa, and the exhalation resistance does not exceed 29.4Pa.
Medical surgical masks have a strong resistance to bacteria and viruses. In daily life, they can be used to prevent the spread of infectious diseases such as influenza and respiratory system, and can also prevent patients from transmitting viruses to others.