Medical masks can be divided into: medical protective masks, medical surgical masks, ordinary medical masks
cooking equipment 1. Medical protective 3 ply mask Medical protective 3ply face mask are suitable for the protection of airborne respiratory tract infectious diseases by medical staff and related staff. face mask 3 ply is a close-fitting self-priming filter medical protection article with a high protection level, especially suitable for contact with airborne in diagnosis and treatment activities. Or the disease occurs in patients with respiratory infections spread by droplets at close range. It can filter the particles in the air, block droplets, blood, body fluids, secretion droplets, etc., which are disposable products. Bacteria, viruses and other pathogens, 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 Induction cooker. The specific indicators are as follows: 1) Filtration efficiency: Under the condition of air flow (85 ± 2) L / min, the filtration efficiency of the aerodynamic median diameter (0.24 ± 0.06) μm sodium chloride aerosol is not less than 95%, which is in accordance 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 Gas stove. 2) Inhalation constraint: under the above flow conditions, the inhalation constraint does not exceed 343.2Pa (35mmH2O). 3) The sample sprayed to the mask under the pressure of 10.9Kpa (80mmHg), the mask enters the technical indicators such as penetration . 4) Nose clips must be installed on the mask. The nose clips are made of bendable plastic materials, and the length is> 8.5cm. 5) Synthetic blood is sprayed towards the mask sample at 10.7kPa (80mmHg) pressure. The mask is clogged and infiltrated. 
2. Medical surgical 3ply mask Medical surgical ffp3 respirator mask are suitable for the basic protection of medical staff or related personnel, as well as the protection against blood, body fluids and splashes during the invasive operation. The protection level is medium and has certain respiratory protection performance. It mainly occurs in a clean environment with a degree of cleanliness of less than 100,000, working in the operating room, nursing patients with low immune function and performing body cavity puncture and other operations. Medical surgical masks can block most bacteria and some viruses, prevent medical staff from being infected, and can also prevent medical staff from calling for gas surgical masks. The filtration efficiency of bacteria is required to reach more than 95%. Disposable medical surgical masks should also be issued to suspicious respiratory patients to prevent the threat of infection to other hospital personnel and reduce the risk of cross-infection, but to avoid infections that are not as effective as medical protective masks. It complies with YY0469-2004 "Technical Requirements for Medical Surgical Masks", and important technical indicators include filtration efficiency, bacterial filtration efficiency and respiratory resistance. The specific indicators are as follows: 1) 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%. 2) Bacterial filtration efficiency: Under the specified conditions, the filtration efficiency of the aerosol of Staphylococcus aureus with an average particle diameter of (3 ± 0.3) μm is not less than 95%; the bacterial filtration rate should be ≥95%; for non-oily particles The filtration rate should be ≥30%. 3) Breathing 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. When the pressure difference △ P of gas exchange between the two ends of the mask is 49Pa / cm, the gas volume should be ≥ 264mm / s. 4) Nose clip and mask band: Nose clip should be added to the mask. The nose clip is made of plastic material, 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. 5) Synthetic blood penetration: After 2ml of synthetic blood is sprayed at the pressure of 16.0kPa (120mmHg) to the outer side of the mask, the inner side of the mask appears to penetrate. 6) Flame retardant performance: mask ffp3 material should be made of non-flammable materials, and ffp3 mask burns less than 5s after leaving the flame. 7) Residual amount of ethylene oxide: The residual amount of propylene oxide should be less than 10μg / g in a sterilized mask through capillary implantation. 8) Skin irritation: The primary irritation index of the mask material should be ≤0.4, and there should be no sensitization reaction. 9) Microbial indicators: total bacterial colonies ≤20CFU / g, no coliform bacteria, Pseudomonas aeruginosa, Staphylococcus aureus, hemolytic streptococci and fungi shall be detected 3. Ordinary medical mask Ordinary medical masks are used to block spouts exhaled from the oral cavity and nasal cavity, and can be used for one-time hygiene care in ordinary medical environments with the lowest protection level. It is suitable for general hygiene care activities, such as sanitation, liquid preparation, cleaning bed units, etc., or the blocking or protection of particles other than pathogenic microorganisms such as pollen. 
