The kn95 face mask is China's national non-oily particle filtering effect greater than or equal to 95%. China is the kn95 face mask. The KN standard is a dust mask standard formulated by China on the basis of the NIOSH standard in the United States. 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 the types of masks that resist non-oily particles greater than 95% and 100%.
KN95-level masks can protect against all kinds of dust, non-oily particles in the air, and viruses in the air. For this new crown pneumonia virus, the best protective effect is the KN95 level mask. If you wear the kn95 mask correctly, it can resist the invasion of the new crown pneumonia virus.
Under normal circumstances, if it is used outdoors, such as subways, buses, supermarkets, shopping malls and other public places, KN95-level masks need to be replaced every 4-6 hours. Replace the KN95 level mask once.
At present, foreign countries, including WHO, have not made a clear conclusion on the best wearing time of N95 masks, and China has not yet made relevant regulations on the use time of masks. Some researchers have done relevant research on the protection efficiency and wearing time of KN95 medical protective masks. The results show that the filtration efficiency of kn95 face masks remains above 95% after wearing them for 2 days, and the respiratory resistance does not change much; the filtration efficiency drops to 94.7% after wearing them for 3 days. %. The advice given by the US CDC is that in the absence of sufficient supplies of masks, as long as the equipment is not visibly soiled or damaged (such as creases or tears), it can be considered for reuse. Regular KN95 grade protective masks have a shelf life because they will lose static electricity and become waste products if stored for a long time. The kn95 face mask can indeed be reused, but it needs professional knowledge to deal with it, so don't take it for granted.
Correct use of kn95 face masks: The most common way to wear a surgical mask is with the white side facing outwards. In fact, generally speaking, the blue side should be facing outwards. Orientation, the metal strip protruding outward or the fold downward is usually the outside. Generally speaking, if the mask is worn correctly, the glasses of the eyes will not fog up. If it fogs up, it is usually because the top of the mask does not fit the face, and the airflow will flow to the gap when breathing, which will reduce the filtration of the mask. effect.