"Medical mask", "medical nursing mask", "medical surgical mask", "medical protective mask" There are "N95", "kn95", and even "FFP2" and so on Are you blind? It looks like a mess. Do you really choose such a variety of masks with different names and types?
Medical surgical mask: yy0469-2011
The medical surgical mask must be manufactured according to the medical standard yy0469-2011. If the enterprise standard set by the enterprise meets or even exceeds the requirements of yy0469, it can also be printed on the outer packaging of the mask (therefore, it is not necessary to have yy0469 to be qualified, but depends on the name of the mask and the content of the enterprise standard for identification); the surgical mask is mainly used for invasive operations, tube placement, etc. in hospitals The key monitoring departments of operation and sensory control also generally require the use of such masks.
Yy0469 has the requirements for bacterial filtration performance of surgical masks. Generally, the filtration efficiency of non oil particles should be more than 30%, and the filtration efficiency of bacteria should be more than 95% (note, this is not the meaning of N95, not to be confused with medical protective masks). In addition, the medical surgical masks also have the requirements for synthetic blood penetration (it can be simply understood as impermeability). Enterprises When making, the mask is generally divided into three layers: the internal absorbent layer, the intermediate filter layer, and the external waterproof layer. Each layer has a special role.
Kn mask: gb2626-2006 / 2019
Due to different workplaces, the particles people come into contact with can be generally divided into two categories: oily and non oily. Among them, the "kn" type mask is mainly used to protect non oily particles, while the "KP" type mask can protect both oily particles and non oily particles. For example, the chemical industry is mostly exposed to oily particles (such as paraffin oil steam), which is generally used KP masks are mainly used in other industries, including ordinary civil use (of course, KP masks can also be used in some civil haze masks).
According to the requirements of gb2626 standard, kn respirator, according to its filtration performance of non oil particles, can be divided again, so that you are familiar with Kn90, kn95 and kn100 respirators. Kn95 respirator is one of the most common respirators, which has a filtration performance of more than 95% for non oily particles (detected by sodium chloride).
See here, I don't know if you have found a problem. Just now, I have told you that the filtering performance of medical surgical mask (yy0469-2011) for non oil particles is ≥ 30%, which is much lower than the requirement of kn95 mask ≥ 95%, so many people naturally think that: kn mask, especially kn95 mask, must be better than medical surgical mask! Is this absolute?
Surgical masks have the requirements of impermeability, generally divided into three layers, the outermost layer is waterproof layer. The main reason for using masks in medical environment is to isolate bacteria. Once bacteria are attached to the outer surface of masks, it is very easy to follow the wet masks to penetrate directly into the inner part of masks. Therefore, impermeability is very important!
However, throughout gb2626, there is no standard requirement for kn respirator to be waterproof, not only kn respirator, but also KP respirator, that is to say, qualified respirators meeting all gb2626 standards have no requirements for anti penetration. At this point, kn mask is not as good as surgical mask!
Is breathing valve good or bad?
Because the doctors and patients who wear masks cannot guarantee that they are healthy and virus-free (infectious in the incubation period), and the respirator air flow with exhalation valve is only one-way protection, which can not cut off the transmission way very well. From the perspective of epidemic control, two-way protection is the most correct way, so this kind of respirator is not recommended.
Standard for protective masks: gb19083-2010
There is no "N95" in gb19083, but "level 1", "level 2" and "level 3" are used to express the filtration efficiency level. Generally, level 1 can meet the requirements of "N95 / kn95". That is to say, as long as any "medical protective mask" in line with gb19083 standard is met, the filtering efficiency of N95 and kn95 will definitely be achieved. In addition, like the medical surgical mask of yy0469-2011, gb19083 also puts forward the requirement of "synthetic blood penetration", and there is an additional parameter requirement of "surface moisture resistance", which clarifies the protective effect of medical protective mask on blood, body fluids and other liquids, which are not available in gb2626 (KN type).
1. Kn respirator conforming to gb2626 can not be used for medical operation, especially for high-risk operations such as tracheotomy and endotracheal intubation, because it can not be guaranteed not to be wet.
2. According to gb19083, the respirator above level 1 can not only achieve 95% filtration, but also prevent liquid penetration, which can be used in various operations of medical institutions.
3. The medical surgical mask conforming to yy0469 is less than 95% filterable, but it can prevent liquid penetration. Because its tightness with the face is not as good as the medical protective mask, it is generally not used for the protection of high-risk operation, but it can meet the ordinary risk operation.
All of the above are for the choice of medical institutions. How should the public choose?
1. Can choose medical surgical mask, try to choose surgical mask, impermeable. If it doesn't use kn type, the respirator conforming to gb19083 level I (available on the packaging box) basically reaches the filter level of N95 / kn95, and the other... Actual protection effect is not ideal.
2. Can choose masks without breathing valve, try to choose masks without breathing valve.