1 Is there a difference between KN95 and N95 masks?
N95 is the certification level of American respirators, certified by the National Institute of Occupational Safety and Health (NIOSH). This type of mask can filter out more than 95% of non-oily particulate matter (aerosol) under the specified air flow (85L / min), so it is named N95. If it can filter more than 99% of particulate matter (aerosol), it is called N99 mask. In addition, corresponding to N95, KN95 is a mask certified by China's GB2626-2006 Respiratory Protection Products Self-Suction Filtering Anti-Particle Respirator Standard.
KN95 and N95 masks have the same protection level, but only follow the test standards of different countries. KN95 masks follow Chinese standards, and N95 masks follow American standards, both of which have a protection efficiency of not less than 95% for non-oily particulates (sodium chloride particulates for experiments).
2 Can KN95 masks be used for first-line protection?
Both KN95 masks and N95 masks include medical and non-medical types. Among them, the masks with the "Medical" mark in the KN95 / N95 masks can be used for the first-line protection of the medical staff during the anti-epidemic period. The masks without the "Medical" mark are not recommended for the medical staff, and can be used by ordinary people. Masks of level 1 and above conforming to GB19083 can not only achieve 95% filterability, but also prevent liquid penetration, and can be used for various operations in medical institutions.
3 Why can KN95 / N95 masks be anti-virus?
Viruses usually do not exist alone in the air, but attach to particles such as droplets, dust, dander, etc. The filtering mechanism of the KN95 and N95 masks is to block these fine particles through the high-performance filter layer in the mask to build a Protective barrier.
Therefore, when wearing KN95 / N95 respiratory protective equipment self-priming filter anti-particulate respirator masks, pay attention to the tightness, should be close to the face, and never leave a "gate of convenience" for viruses and bacteria. There are "exhalation valve" type masks.
4What is the difference between medical and non-medical masks in KN95 / N95 masks?
The main difference is that the outer surface of the medical type mask has been hydrophobically treated. The medical surgical masks of GB19083-2010 and YY0469-2011 clearly put forward the requirements of "synthetic blood penetration", the parameter index of "surface moisture resistance", and the medical protective mask Protective effect on blood, body fluids and other liquids. In layman's terms, just like a water drop falling on a lotus leaf, the liquid cannot penetrate on the surface of the mask, which can prevent medical staff from often touching alcohol, blood, etc. to prevent it from quickly penetrating; it is not the medical type KN95 / N95 masks will not go through this special treatment.
The most protective function of KN95 and N95 protective masks is the filter layer. The filter layer is made of polypropylene melt-blown microfiber electret material. The outer surface of the mask has not been treated with water repellent. The application of water and alcohol will destroy the material The structure of the filter greatly reduces the filtering effect. What's more, the blood often contains bacteria, viruses, etc., and the hospital's application scenario determines that the medical staff will be exposed to the patient's blood environment with a high probability. Therefore, the hydrophobic treatment of the surface of the medical mask is essential. And ordinary people have little chance of encountering alcohol and blood. As long as the mask is changed regularly, the outside will not be harmed without this treatment.
5 What is the protective effect of KN95 / N95 mask with breathing valve?
KN95 / N95 masks are also divided into breathing valve and no breathing valve. For masks, breathability and filtration efficiency are always a contradiction. If the filtration effect is good, you will often feel suffocated. Breathing valve is designed to relieve suffocation.
The exhalation valve and the inhalation valve are a mechanical switch. When inhaled, the valve is opened when exhaled. The air is "screened" through the filter layer. The valve is opened during exhalation to reduce the sense of resistance. The problem is that it is unclear whether this mechanical switch will suddenly break when worn, or it will be caught by fine particles, allowing harmful particles of air carriers that have not passed through the filter layer to take advantage of it. Therefore, all medical type masks have no breathing valve. At the same time, we also appeal that during this anti-epidemic period, especially when the surrounding environment is relatively poor, ordinary people also try to choose KN95 / N95 masks or medical surgical masks without breathing valves.