Quality standards and protective effects of various masks
The epidemic situation of the new type of coronavirus in this period is very serious, and the sales volume of masks has increased greatly in many places, but many people do not understand the quality standards of various masks and their protective effects. This article explains the quality standards of several common masks on the market for your reference. Reasonably choose different types of masks for different functions.
1. Medical protective mask
Medical protective mask is suitable for the protection of airborne respiratory infectious diseases by medical personnel and related staff. It is a kind of self-adhesive filtering medical protective equipment with high protection level, especially suitable for contact with airborne transmission during diagnosis Or wear it for patients with respiratory infections that are transmitted by droplets at close range. It can filter the particles in the air and block droplets, blood, body fluids, secretion droplets, etc. It is a disposable product. Medical protective masks can prevent most bacteria, viruses and other pathogens. WHO recommends that medical personnel use protective masks against particulate matter to prevent virus infection in the hospital air.
Medical protective masks meet the GB19083-2003 "Technical Requirements for Medical Protective Masks" standards. Important technical indicators include non-oily particle filtration efficiency and airflow resistance. The specific indicators are as follows:
1) Filtration efficiency: Under the condition of air flow rate (85 ± 2) L / min, the filtration efficiency for aerodynamic median diameter (0.24 ± 0.06) μm sodium chloride aerosol is not less than 95%, which is in line with N95 ( Or FFP2) and above. Can block airborne infection factors <5μm in diameter or close contact with droplet-borne infection factors.
2) Inspiratory resistance: Under the above flow conditions, the inspiratory resistance does not exceed 343.2Pa (35mmH2O).
3) The sample sprayed to the mask under the pressure of 10.9Kpa (80mmHg) should not have any technical indicators such as penetration inside the mask.
4) The mask must be equipped with a nose clip. The nose clip is made of a flexible plastic material with a length of> 8.5cm.
5) The synthetic blood is sprayed on the mask sample at a pressure of 10.7kPa (80mmHg), and the inside of the mask should not penetrate.
2. Medical surgical mask
Medical surgical masks are suitable for basic protection of medical personnel or related personnel, as well as protection against blood, body fluids and splashes during invasive operation. The protection level is medium and it has certain respiratory protection performance. It is mainly worn in a clean environment with a cleanliness of less than 100,000, operating in the operating room, nursing patients with low immune function, and performing body cavity puncture.
Medical surgical masks can block most bacteria and some viruses, prevent medical staff from being infected, and prevent direct discharge of microorganisms carried by medical staff, which poses a threat to patients undergoing surgery. Medical surgical masks require a filtration efficiency of more than 95% for bacteria. For suspicious respiratory patients, disposable medical surgical masks should also be distributed to prevent other hospital personnel from posing a threat of infection and reduce the risk of cross-infection, but to avoid infections less effective than medical protective masks.
It complies with the YY0469-2004 "Technical Requirements for Medical Surgical Masks" standard. 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 for aerodynamic median diameter (0.24 ± 0.06) μm sodium chloride aerosol is not less than 30%.
2) Bacterial filtration efficiency: Under specified conditions, the filtration efficiency of Staphylococcus aureus aerosols with an average particle diameter of (3 ± 0.3) μm is not less than 95%; the filtration rate of bacteria should be ≥95%; The filtration rate should be ≥30%.
3) Breathing resistance: In the condition of filtering efficiency and flow rate, the inhalation resistance does not exceed 49Pa, and the exhalation resistance does not exceed 29.4Pa. When the pressure difference △ P for gas exchange on both sides of the mask is 49Pa / cm, the gas flow rate should be ≥264mm / s.
4) Nose clip and mask strap: The nose clip should be equipped with a nose clip made of a plastic material, and the length of the nose clip should be greater than 8.0cm. Mask strips should be easy to wear, and the breaking strength at the connection point between each mask strip and the mask body should be greater than 10N.
5) Synthetic blood penetration: After 2ml of synthetic blood is sprayed on the outer side of the mask at a pressure of 16.0kPa (120mmHg), the inner side of the mask should not penetrate.
6) Flame retardant performance: Non-flammable materials should be used for mask materials, and the mask will burn for less than 5s after leaving the flame.
7) Ethylene oxide residue: Ethylene oxide sterilized masks should have less than 10 μg / g of ethylene oxide.
8) Skin irritation: The primary irritation index of the mask material should be ≤0.4, and there should be no allergic reaction.
9) Microbiological indicators: The total number of bacterial colonies is ≤20CFU / g. Coliform bacteria, Pseudomonas aeruginosa, Staphylococcus aureus, hemolytic streptococcus and fungi shall not be detected.
3. General medical mask
Ordinary medical masks are used to block the spray from the mouth and nasal cavity. They can be used for disposable sanitary care in the ordinary medical environment with the lowest protection level. Suitable for general health care activities, such as sanitary cleaning, dosing, cleaning bed units, etc., or the blocking or protection of particles other than pathogenic microorganisms such as pollen.
It meets the relevant registered product standards (YZB), and generally lacks the filtration efficiency requirements for particles and bacteria, or the filtration efficiency requirements for particles and bacteria are lower than medical surgical masks and medical protective masks, and only reach 20.0% for aerosols with a diameter of 0.3 μm -25.0% protection effect, can not reach the filtration efficiency of particles and bacteria, can not effectively prevent pathogens from invading through the respiratory tract, can not be used for clinical invasive operations, can not protect particles and bacterial viruses, only limited to dust particles Or aerosol plays a certain mechanical barrier.
Q / GZBWK 1-2015 type
Q / GZBWK 1-2015 is an enterprise standard for a manufacturer of labor protection supplies. The meaning of its code:
Q / —— enterprise standard code;
GZBWK-Pinyin prefix of the company name;
1-2015-Standard No. 1 issued in 2015
Q / GZBWK 1-2015 Non-woven masks 1 Scope This standard specifies the definition, technical requirements, test notes, inspection rules, marking, packaging, transportation and storage requirements of non-woven masks. This standard applies to protective masks worn to filter out droplet-type pollutants in air pollution environments in daily life. This standard does not apply to hypoxic environments, underwater operations, escape, firefighting, medical and industrial dust and anti-respiratory respiratory protection products.
The N95 mask has a filtration efficiency of more than 95% for particles with an aerodynamic diameter ≥ 0.3µm. The aerodynamic diameter of air bacteria and fungal spores mainly varies between 0.7-10µm, and it is also within the protective range of N95 masks. Therefore, N95 masks can be used for respiratory protection of certain particulates, such as dust generated during grinding, cleaning and processing of minerals, flour and certain other materials. Hazardous volatile gas particles. Can effectively filter and purify the inhaled abnormal odors (except toxic gases), help reduce the exposure level of certain inhalable microbial particulates (such as mold, anthrax, tuberculosis, etc.), but it doesn't eliminate the risk of contact transmission, illness of death.
The US Department of Labor has recommended that medical personnel use N95 masks to prevent microbial airborne diseases such as influenza and tuberculosis.
N95, N99, N100, R95, R99, R100, P95, P99, P100, a total of 9 types. These protection levels can cover the protection range of N95.
"N" means non-oil-resistant, suitable for non-oily particulate matter, and there is no limitation on the use time.
"R" means resistant to oil, suitable for oily or non-oily particles. If used for the protection of oily particles, the use time should not exceed 8 hours.
"P" means oil proof, suitable for oily or non-oily particles. If used for oily particles, the usage time should follow the manufacturer's recommendations.
"95", "99" and "100" refer to the level of filtration efficiency when tested with 0.3 micron particles. "95" means the filtration efficiency is above 95%, "99" means the filtration efficiency is above 99%, and "100" means the filtration efficiency is above 99.7%.
1. Buy medical surgical masks with production license and product registration number, and beware of "three-none" products.
2. To prevent virus droplets, the mask must meet at least the YY 0469-2011 standard (ordinary medical masks do not work).
3. For ordinary people in ordinary environment, genuine KN90 or N90 and above masks (in accordance with GB 2626-2006) are more than enough, no exhalation valve is preferred; an exhalation valve is also acceptable.
4. Frontline medical personnel who may be directly exposed, please use GB 19083-2010 medical protective masks to protect themselves.
5. You can only buy ordinary masks, and you must wear them! Can block part, but the effect is limited.