It is quite cost-effective to see a self-operated store in Bai Yue, with an average of one yuan, which is already very low. I placed three orders in a row. When I bought it for my relatives, I found that N95 had a fish mouth. Many people said that this mask was more comfortable than ordinary masks, so I decisively placed another order (100). After receiving the goods, I found that there was no N95 on either the outer packaging or the mask. In fact, for ordinary people, they will recognize N95 and will not ask about the implementation standards.
After communicating with customer service, it was said that the manufacturer didn't print it, and the implementation standard was GB 19083-20 10, which is the standard of medical protective masks and N95. I was thinking, why? How good is it to print it directly? ? So I searched the relationship between GB 19083-20 10 and N95.
1. Medical protective mask
Medical protective masks are suitable for medical staff and related staff to infect respiratory tract through air; The medical protective mask conforms to GB 19083-2003 Technical Requirements for Medical Protective Masks, and its important technical indicators include filtration efficiency of non-oily particles and airflow resistance. Specific indicators are as follows: [3]
1) filtration efficiency: under the condition of air velocity of (85 2) l/min, the filtration efficiency of sodium chloride aerosol with aerodynamic median diameter of (0.24 0.06) micron is not less than 95%, that is, it meets the grade of n 95 (or FFP2) and above. Diameter that will hinder air transmission
2) Suction resistance: Under the above flow conditions, the suction resistance shall not exceed 343.2Pa(35mmH2O).
3) The samples sprayed on the mask under the pressure of 10.9Kpa(80mmHg) shall have no technical indicators such as penetration.
4) The mask must be equipped with a nose clip, which is made of flexible plastic material with a length of >; 8.5 centimeters.
5) Synthetic blood is sprayed at a pressure of 10.7kPa(80mmHg) on the mask sample, and there should be no infiltration inside the mask.
2. Medical surgical masks
Medical surgical masks are suitable for the basic protection of medical personnel or related personnel, as well as the protection against blood and body fluids from spreading and splashing during invasive operations. The protection level is moderate and it has certain respiratory protection performance. It conforms to YY0469-2004 Technical Requirements for Medical Surgical Masks, and its important technical indicators include filtration efficiency, bacterial filtration efficiency and respiratory resistance. Specific indicators are as follows:
1) filtration efficiency: under the condition of air flow of (30 2) l/min, the filtration efficiency of sodium chloride aerosol with aerodynamic median diameter of (0.24 0.06) micron is not less than 30%.
2) bacterial filtration efficiency: under specified conditions, the filtration efficiency of Staphylococcus aureus aerosol with an average particle size of (3 0.3) micron is not less than 95%; The bacterial filtration rate should be ≥ 95%; The filtration rate of non-oily particles should be ≥30%.
3) Respiratory resistance: Under the conditions of filtration efficiency and flow rate, the inspiratory resistance should not exceed 49Pa and the expiratory resistance should not exceed 29.4Pa. When the pressure difference △P between the two sides of the mask is 49Pa/cm, the gas flow rate should be ≥ 264 mm/s. ..
4) Nose clips and mask straps: the mask should be equipped with nose clips, the nose clips should be made of plastic, the length should be more than 8.0cm, the mask straps should be easy to wear, and the breaking strength of the connection point between each mask strap and the mask body should be greater than 10N.
5) Penetration of synthetic blood: After 2ml of synthetic blood is sprayed on the outside of the mask at a pressure of 16.0kPa( 120mmHg), the inside of the mask should be impermeable.
6) Flame retardancy: The mask material should be nonflammable and burn for less than 5s after leaving the fire.
7) Residual amount of ethylene oxide: The residual amount of ethylene oxide in the mask sterilized by ethylene oxide should be less than.
10 μ g/g.
8) Skin irritation: The first-class irritation index of the mask material should be ≤0.4, and there should be no allergic reaction.
9) Microbial indicators: the total number of colonies is ≤20CFU/g, and coliform bacteria, Pseudomonas aeruginosa, Staphylococcus aureus, hemolytic streptococcus and fungi shall not be detected.
3. Ordinary medical masks
Ordinary medical masks are used to block the splashes exhaled by oral cavity and nasal cavity, and can be used for disposable health care in general medical environment, with the lowest protection level. It conforms to the relevant registered product standards (YZB), and generally lacks the requirements for particulate matter and bacteria filtration efficiency, or the requirements for particulate matter and bacteria filtration efficiency are lower than those for medical surgical masks and medical protective masks. Only the aerosol with a diameter of 0.3μm can achieve a protective effect of 20.0%-25.0%, but it can not effectively prevent the filtration efficiency of particulate matter and bacteria, can not be used for clinical invasive operation, and can not protect particulate matter and bacterial viruses.
? As the Spring Festival approaches, you must do personal protection every day and try to avoid going to closed and crowded places. Be sure to wear a mask.
Come on! ?