What is the difference between KN95 mask, N95 mask, medical mask, medical surgical mask FFP2 and other masks

Wuhan pneumonia epidemic broke out, everyone put on masks! In addition to the difficulty of buying masks, there is also the problem of the difficulty of buying masks. Nowadays, there are so many kinds of masks. In all kinds of masks, how do we distinguish and choose?

It is mainly classified into two categories: one is medical masks and the other is civilian masks. Medical surgical masks, medical protective masks, N95, FFP2 can be used for the protection of medical institutions, KN95 can not be used in medical institutions, but ordinary people can choose their own, what is the difference between other masks, first look at this table.

2. Medical: Medical surgical mask: YY0469-2011
Medical surgical masks must be produced according to the medical standard YY0469-2011. If the enterprise standard set by the company meets or exceeds the requirements of YY0469, it can also be printed on the outer packaging of the mask (thus, it is not necessary to have YY0469 to be qualified, specific It still depends on the name of the mask and the content of the enterprise logo to identify); surgical masks are mainly used for invasive operations such as surgery and tube placement in hospitals, and key monitoring departments of sensory control generally require the use of such masks.

YY0469 has requirements for bacterial filtration performance for surgical masks. Generally, the filtration efficiency of non-oily particles should reach more than 30%, and the filtration efficiency of bacteria must reach more than 95% (note that this is not the meaning of N95, and should not be confused with medical protective masks ) In addition, medical surgical masks also have requirements for the permeability of synthetic blood (which can be simply understood as anti-permeability). When the company manufactures, the mask is generally divided into three layers: the inner water absorption layer, the middle filter layer, and the outer waterproof layer Each layer has a special role (focus here, we will use it later).

3. Medical: Medical protective mask
Medical protective masks, followed by disposable medical nursing masks, also called medical protective masks, comply with the GB19083-2003 standard. Important technical indicators include non-oily particle filtration efficiency and airflow resistance. The filtration efficiency of sodium oxide aerosol with diameter (0.24 ± 0.06) μm is not less than 95%, which is in line with N95 and above. Inhalation resistance does not exceed 343.2Pa.

4. Civil: KN mask: GB2626-2006 / 2019
Due to the different workplaces, the particulates that people are exposed to can generally be divided into two categories: oily and non-oily. Among them, "KN" masks are mainly used to protect non-oily particulates, while "KP" masks can protect oily particulates. It can also protect non-oily particulates. For example, the chemical industry is more exposed to oily particulates (such as paraffin oil vapor, etc.). Generally, KP masks are used; other industries including ordinary civilians, KN ​​masks are mainly used (of course, there are also some civilian fog Haze masks can use KP masks).

According to the requirements of the GB2626 standard, KN masks are divided again according to their filtration performance for non-oily particulate matter, and there are three masks that are familiar to everyone, KN90, KN95, and KN100. Among them, the KN95 mask has a filtration performance of more than 95% for non-oily particulate matter (tested with sodium chloride), which is one of the most common masks. See the table below for details
See here, I do n’t know if you have found a problem. Just now, I have told you that medical surgical masks (YY0469-2011) require that the filtering performance of non-oily particulates is ≥30%, which is ≥95% of KN95 mask The requirements are much lower, so many people naturally think that: KN masks, especially KN95 masks, are definitely better than medical surgical masks! Is this absolute?

Surgical masks have anti-penetration requirements and are generally divided into three layers. The outermost layer is a waterproof layer. The main reason for using masks in the medical environment is to isolate bacteria. Once bacteria are attached to the outer surface of the mask, it is easy to follow the wet mask Penetration into the inside of the mask, so anti-penetration is very important!

Throughout the entire GB2626, no standard requirements for waterproofing of KN masks have been found, not only KN95 masks, but also KP masks. That is to say, qualified masks that meet all the standards of GB2626 have no requirements for penetration resistance. At this point, KN masks are not as good as surgical masks!