Everyone knows that KN95 masks can protect against the new crown pneumonia virus. But how should I choose a mask? Today, I will introduce you to the knowledge of KN95 masks.
1. What is a KN95 mask?
KN95 masks are China's national non-oily particulate matter filtering effect greater than or equal to 95% of the level of masks. China is KN95 masks. The KN standard is a dust mask standard formulated by China on the basis of the US NIOSH standard. The common protection efficiency is divided into 90, 95 and 100, of which 90 means that the effect of resisting non-oily particles is greater than 90%, and the other 95 and 100 are mask types that prevent non-oily particles greater than 95% and 100%.
2. What is the use of KN95 masks?
KN95 masks can protect against all kinds of dust, non-oily particles, and viruses in the air. For this new type of pneumonia virus, the best protection effect is KN95 masks. If KN95 is worn correctly Masks can resist the attack of the new pneumonia virus.
3. How often do KN95 masks be replaced?
Under normal circumstances, if it is used outdoors, such as subways, buses, supermarkets, shopping malls and other public places, KN95 masks need to be replaced every 4-6 hours, but if it is in a new pneumonia virus-affected area, it is recommended to be in time in 2 hours Replace the KN95 mask once.
At present, foreign countries, including WHO, have not made clear conclusions on the best wearing time of N95 masks, and my country has not yet made relevant regulations on the use time of masks. Some researchers have done relevant studies on the protection efficiency and wearing time of KN95 medical protective masks. The results show that KN95 masks are worn for 2 days, the filtration efficiency remains above 95%, and the respiratory resistance does not change much; the filtration efficiency is reduced to 94.7 after wearing for 3 days. %. The advice given by the US CDC is that if there is no sufficient supply of masks, as long as the equipment is not obviously dirty or damaged (such as creases or tears), you can consider reusing it.
The regular KN95 level protective masks have a shelf life because they will lose static electricity and become waste products if they are stored for a long time. KN95 masks can indeed be reused, but they need to be handled with professional knowledge. Don't take it for granted.