- Leukemia (AML): Bristol-Myers Squibb Onureg was approved by EU
- Diet can change intestinal and breast flora and affects breast cancer risk
- WHO: Delta variant will become the world main popular variant virus strain
- Clinical application of interleukin in tumor immunotherapy
- Red meats: DNA damage and colorectal cancer-related gene mutations
- Why reversing intravenous thrombolysis after DOAC is not recommended?
Classification and standards of masks
Classification and standards of masks. Mask standards of China, US, EU, Austrilia, Japan and South Korea.
Classified by shape
According to the shape of the mask, there are three types: flat type, folding type and cup-shaped. Flat masks are easy to carry, but have poor adhesion; folding masks are easy to carry; cup-shaped breathing space is large, but not convenient to carry.
Classified by wearing style
- Head-wearing style: suitable for workshop workers who wear it for a long time, and it is troublesome to wear.
- Ear-wearing style: easy to wear, suitable for frequent wearing and taking off.
- Neck-wearing style: Use S-hooks and some soft material connectors. The connecting ear straps are converted to neck straps. It is suitable for long-term wear and is more convenient for workshop workers such as wearing helmets or protective clothing.
Classified by materials used
- Gauze masks: There are still some workshops using gauze masks, but the GB19084-2003 standard they follow is low, and it does not meet the GB2626-2019 standard, and can only protect against large particles of dust.
- Non-woven masks: Disposable protective masks are mostly non-woven masks, mainly physical filtration supplemented by electrostatic adsorption.
- Cloth masks: Cloth masks only have the effect of keeping warm without filtering out the effect of very small particles such as PM.
- Paper mask: suitable for food, beauty and other industries, with good air permeability, easy to use and comfortable, etc. The paper used follows the GB/T22927-2008 standard.
- Masks made of other materials, such as new biological protective filter materials.
Classified by scope of application
- Medical masks: There are three types in China, general medical masks, medical surgical masks, and medical protective masks.
- Particulate protective masks: industrial use conforms to the GB2626-2019 standard, special labor protection products safety mark certification (LA certification), in 2015 from compulsory certification to voluntary certification. If it is used to prevent smog, it needs to use the insert type, which must meet the GB/T32610-2016 standard. Civilian use complies with GB/T32610-2016 standard.
- Warm cloth masks: Warm masks, suitable for winter wear, only need to meet the relevant standards of fabrics.
- Other special industries: such as chemical industry.
Classified by protection level
Different countries and different industries have formulated different standards, which are divided into different protection levels according to different particle filtration efficiency, which will be described in detail in the standard section.
Respiratory protective masks can be divided into filter type and isolated type. Filter type can be divided into air supply filter type and self-priming filter type.
The latter can be divided into half mask and full mask; isolated type can be divided into air supply type and air-carrying type. The two types include positive pressure and negative pressure respectively.
Technical standards for masks
China’s Mask Standards
China produces more than 50% masks in the world and is the biggest market of various masks . 3M and Honeywell also produce masks under Chinese standard. Chinese companies make hug quantity of masks per other countries’ standard.
Different types of masks in China follow different standards, and the scope of application of different masks is different. Several major standards for Chinese masks are
- GB2626-2019 respiratory protection self-priming filter particulate respirator,
- GB/T32610-2016 technical specifications for daily protective masks,
- YY/T0969-2013 disposable medical masks,
- YY0469-2011 medical surgery Masks,
- GB19083-2010 medical protective mask technical requirements．
The main Chinese standards are described in detail below:
The first edition of this standard was released in 1981 (GB2626-1981). It was updated three times in 1992, 2006, and 2019. The 2019 edition was changed to “Respiratory protection self-priming filter type anti-particulate respirator”, without The word “supplies”.
The GB2626-2019 version was released on 2019-12-31 and implemented on 2020-07-01. The standard specifies the classification and labeling, technical requirements, detection methods and identification of self-priming filter anti-particulate respirators.
This standard was proposed by the State Administration of Work Safety and under the jurisdiction of the National Standardization Technical Committee for Personal Protective Equipment (SAC/TC112). Compared with the 2006 version, on the basis of following the basic principles of science, standardization, coordination, timeliness, etc., according to the trend of scientific progress and product development, adjust the respiratory resistance index and improve the detection method without reducing the protection ability. , Optimize the lower field of vision of the half mask, and improve the comfort of the product.
The standard filter element is divided into two categories (KN and KP) according to the filtering performance. The KN category is only suitable for filtering non-oily particles, including KN90 (≥90%), KN95 (≥95%), KN100 (≥99.97%). level. KP type is suitable for filtering oily and non-oily particulate filter elements, including KP90 (≥90%), KP95 (≥95%), KP100 (≥99.97%) three levels.
The number after KN and KP refers to the level of filtration efficiency. The higher the number, the better the filtration effect. KN masks have not tested synthetic blood penetration and surface moisture resistance. Therefore, such masks can block the virus when used for a short time, but cannot be used to contact patients who may be splashed or contact patients for a long time.
GB/T 32610-2016 Technical Specification for Daily Protective Masks is a civil mask standard. This standard was proposed by the China Textile Industry Federation and under the jurisdiction of the National Textile Standardization Technical Committee (SAC/TC209). The scope of application is shown in Figure 6.
According to the filtration efficiency, it is divided into: Ⅰ, Ⅱ, and Ⅲ. The corresponding filtration efficiency: salty medium is ≥99%, ≥95%, ≥90%; oily medium is ≥99%, ≥95%, ≥ 80%. The protective effect of masks is divided into A, B, C, and D levels from high to low. The ambient air quality applicable to masks at all levels is severe pollution, severe pollution and below, severe pollution and below, and moderate pollution and below.
Masks at all levels should be able to reduce the concentration of inhaled particulate matter (PM) to ≤75μg/m (air quality index category and above) under the corresponding air pollution environment. When the protective effect level of the mask is A, the filtration efficiency should reach Ⅱ and above; when the protective effect of the mask is B, C, D, the filtration efficiency should reach Ⅲ and above.
This standard is an industry standard for disposable medical masks. It was released on 2013-10-21 and implemented on 2014-10-01. Ordinary medical masks meet this standard, are suitable for general protection of medical staff, and are only used in ordinary medical environments (see Figure 6). There are many names for general medical masks, including medical care and disposable medical care. Medical masks without the words “protection” or “surgical” in the name are all ordinary medical masks. The core indicators of this level of masks include bacterial filtration efficiency and ventilation resistance. They are not required to have a barrier effect on blood or have no tightness requirements. See Chart 3.
Medical Surgical Masks (YY0469-2011) is the industry standard for medical surgical masks. It was issued on December 31, 2011 and implemented on June 1, 2013. The first edition of the medical surgical mask industry standard (YY0469-2004) has been replaced by the 2011 edition. It is suitable for disposable masks worn by clinical medical staff during invasive operations (see Figure 6). They are commonly used medical masks in operating rooms and other environments where there is a risk of body fluids and blood splashing. The outer packaging must be clearly marked as medical surgical masks. The core indicators of this type of mask include bacterial filtration efficiency, particle filtration efficiency, synthetic blood penetration resistance, and ventilation resistance (see Table 3). There is no strict requirement for facial fit like the medical protective mask standard, and the filtration efficiency of bacteria is ≥ 95%, the filtration efficiency of particles is limited (≥30%).
GB 19083-2010 for Medical Masks
The technical requirements of GB19083-2010 for medical protective masks were released on 2010-09-02 and implemented on 2011-08-01. The first version is GB19083-2003, which was formulated under the general situation of China’s fight against SARS. It was issued urgently on April 29, 2003. Implementation, there were no medical protective masks before SARS.
This standard is applicable to the medical working environment to filter particles in the air, block droplets, blood, body fluids, secretions, etc., including various infectious viruses (see Figure 6). The core indicators of this type of mask include particle filtration efficiency, synthetic blood penetration resistance, ventilation resistance, surface moisture resistance, good adhesion, and total fitness factor (see Table 3). Medical protective masks have a good fit with the wearer’s face. According to the filtration efficiency of non-oily particles, medical protective masks are divided into level 1 (≥95%), level 2 (≥99%), and level 3 (≥99.97%).
Medical protective masks stipulate that the filtration efficiency of masks for non-oily particles is ≥95%, and it is in line with N95 or FFP2 and above.
The protective capabilities of Chinese medical masks are medical protective masks, medical surgical masks, and ordinary medical masks in descending order.
▲The main standards and scope of application of masks in China from “Chinese Journal of Infection Control”
U.S. Mask Standard
The American NIOSH standard classifies the filter material and filtration efficiency of masks, and this standard is highly recognized worldwide. According to the filter material of the middle layer of the mask, it is divided into three types: N, R, P series, and each can be divided into three levels according to the filtration efficiency.
- N is used to protect against non-oily suspended particles. Generally, non-oily particles refer to coal dust, cement dust, acid mist, microorganisms, etc. The droplets produced by talking or coughing are not oily. In the current haze pollution, most of the suspended particles are non-oily. Oily particulate matter refers to cooking fume, oil mist, asphalt fume, etc., such as cooking fume produced by cooking is oily particulate matter.
- R and P are used to protect non-oily and oily suspended particles. Compared with R series,
- The P series has been used for a relatively long time, and the specific use time is based on the labels of different manufacturers.
- N95 mask is a type of mask in the N series with a filtration efficiency of ≥95%. When the wearer’s face is tested for tightness, it is ensured that air can enter and exit through the mask when it is close to the edge of the face. Only those that meet this test will be issued N95 Certification number. During the special period of SARS prevention, WHO temporarily recommends medical staff to use N95 masks certified by the United States NIOSH.
- N95 masks are not equal to medical protective masks. Medical protective masks require that the filtering effect of masks meet the requirements of N95, and have surface moisture resistance and blood barrier capabilities.
The ASTMF2100 standard is a medical standard that divides masks into three levels: low protection (Level1), medium protection (Level2) and high protection (Level3). The higher the level, the better the protection performance. Level1 and Level2 masks are usually called procedure masks; Level3 masks can be used in the operating room, also called surgical masks. When the chance of exposure to the virus is particularly high, a higher level of protection should be selected.
ASTM certification requires masks to meet relevant standards in four aspects: bacterial filtration efficiency, particle filtration efficiency, synthetic blood penetration resistance and pressure difference.
- Level1：It can block 95% of bacterial particles, even if it only reaches low protection standards, it is enough to protect general community users;
- Level2 and Level3 (medium to high protection standards) require masks to block at least 98% of bacteria and particles, and the pressure difference is only lower than 49.0Pa/cm. The lower protection standards are looser, because it is difficult to achieve better protection At the same time maintain breathability.
- The main difference between Level3 medium and high protection standards is that the high protection (Level3) standards have higher requirements for the ability to block liquids.
Medical N95 masks need to not only meet the FDA Surgical Masks-Premarket Notification Submissions Guidance for Industry and FDA Staff standards, but also meet NIOSH requirements for N95 masks. The synthetic blood penetration and surface moisture resistance have been tested. The FDA standard is basically Follow the ASTMF2100 standard.
The European Union’s European Union (Conformite Europeenne, CE) certification standards for masks include：
Among them, BSEN149 is widely used and is a filter half mask that can protect against particles. According to the tested particle penetration rate, it is divided into P1 (FFP1), P2 (FFP2), P3 (FFP3) three levels, FFP1 low filter effect ≥80%, FFP2 low filter effect ≥94%, FFP3 low filter effect ≥97%. The filtration efficiency of FFP2 masks is very close to that of medical protective masks, KN95 masks, and N95 masks mentioned above.
Medical masks must follow the BSEN14683 standard (Medical face masks-Requirement sand test methods), which can be divided into three levels: low standard Type I, then Type II and Type IIR. See Table 3. The previous version is BSEN14683:2014, which has been replaced by the new version BSEN14683:2019. One of the main changes in the 2019 version is the pressure difference. The Type I, Type II, and Type II R pressure differences have increased from 29.4, 29.4, and 49.0 Pa/cm in the 2014 version to 40, 40, and 60 Pa/cm, respectively.
Australia AS/NZS1716:2012 is the standard for respiratory protection devices in Australia and New Zealand. This standard specifies the procedures and materials that must be used in the manufacture of anti-particle masks, as well as certain tests and performance results to ensure their safe use. The standard is divided into three categories, P1: low filter effect ≥ 80%; P2: low filter effect ≥ 94%; P3: low filter effect ≥ 99%. The Australian medical mask standard is AS4381:2015, which is divided into Level1, Level2, and Level3 according to the core indicators.
Japan’s JIS T8151: 2018 standard
Japan’s JIS T8151: 2018 standard is the standard for respiratory protection devices, and it is also the verification standard of the Ministry of Health, Labour and Welfare (MHLW) of Japan. The common disposable salt particle filtration specifications are as follows, DS1: low filtration effect ≥ 80%; DS2: low filtration Effect ≥99%; DS3: low filtration effect ≥99.9%. T
South Korea’s Standard
The KF (Korean filter) series of mask standards in South Korea. The KF series of standards are the Korean mainstream mask standards (Regulations on the Approval, Notification, and Evaluation of) issued by the Ministry of Food and Drug Safety (MFDS). Quasi-Drugs). KF series are divided into KF80, KF94, KF99. KF80: ≥80% (salt medium only); KF94: ≥94% (oily and saline medium); KF99: ≥99% (oily and saline medium)