Original title: About the use of KN95 masks: All the answers you want to know are here! Say it again: why wear a mask! Coronavirus is spread from person to person, usually when someone comes into contact with the secretions of an infected person. The infectivity of the virus directly affects the route of transmission. The current transmission route of the new coronavirus is not yet clear, but according to past experience, exposure to body fluids splashed by coughing or sneezing of infected people, or shaking hands with infected people may lead to infection. You can also get the virus if your hands touch something that an infected person has touched, and then touch your own mouth, nose, or eyes. Normally, there is about 1 liter of liquid in the lungs, and every time you sneeze, the lungs spray the liquid like a squeezed mineral water bottle. Once outside the body, they divide into more than 40,000 small droplets, each containing a large number of viruses and bacteria. Due to the influence of huge thrust in the body,Virus Prevention Mask 3 Ply with Earloop, the velocity of these liquids can be as high as 35 meters per second, and the propagation distance can reach 3 to 8 meters. Come on, this picture is more intuitive. The reason why SARS in 2003 was so terrible was that it spread through droplets so fast that it was difficult for people to control it. Influenza in Southeast Asia arrived in South China on Monday, and spread to the whole country on Monday. So be sure to wear a mask!!! Even if you come into contact with an infected person, wearing a mask can prevent you from inhaling the virus directly in the droplets. Be sure to wash your hands frequently! Even if the virus is left on the hand, washing the hand can block the virus from entering the body through the hand. Is there a difference between KN95 and N95? N95 mask is actually a respirator,Full Body Disposable Coverall, which is a kind of respiratory protective equipment, designed to fit the face more closely than ordinary masks, and can filter particles in the air very effectively. Where N stands for Not resistant to oil, which can be used to protect against non-oily suspended particles; 95 means that the filtration efficiency is greater than or equal to 95%, which means that after careful testing, the respirator can block at least 95% of very small (0.3 micron level) test particles. In terms of design, according to the priority of the wearer's own protection ability (from high to low): N95 mask surgical mask ordinary medical mask ordinary cotton mask. Expand the full text If worn correctly, the filtering ability of N95 is better than that of ordinary masks and medical masks. However, the risk of contracting disease or death cannot be 100% eliminated even if the wear is fully compliant. KN95 is one of the levels specified in Chinese standard GB2626-2006. N95 is one of the levels specified in American standard 42 CFR 84. The technical requirements and test methods of these two levels are basically the same. The filtration efficiency reaches 95% under the corresponding standard. How long can the KN95 mask be used? At present, there is no clear conclusion on the best wearing time of N95 mask in foreign countries, KN95 Face Mask ,Against Bacteria Breathable KN95 Face Mask, including WHO, and there is no relevant regulation on the use time of masks in China. Some researchers have done relevant research on the protective efficiency and wearing time of N95 medical protective mask. The results show that the filtering efficiency remains above 95% N95 mask wearing for 2 days, and the respiratory resistance changes little; the filtering efficiency decreases to 94.7% after wearing for 3 days. The CDC advises that in the absence of an adequate supply of masks, as long as the device is not visibly soiled or damaged (such as creased or torn), it can be considered for reuse. Replace the mask in time when the following conditions occur: 1. When the respiratory impedance increases significantly ； 2. When the mask is broken or damaged ； 3. When the mask and the face can not fit tightly ； 4. The mask is contaminated (In case of blood stains or droplets and other foreign bodies); 5. Used in individual ward or patient contact (Because the mask has been contaminated); Do you need a breather valve? N95 is divided into two types with and without exhalation valve. For people with chronic breathing problems, heart disease, or other conditions with symptoms of dyspnea, an N95 respirator may make it more difficult for the wearer to breathe, so a N95 mask with an exhalation valve can help them exhale more easily and help reduce heat buildup. The exhalation valve is exquisitely designed with several layers of flaps. When inhaling, the flap closes tightly to ensure that no particles enter. When you exhale, the flap opens, allowing the hot, humid air to escape. At the same time, there is a soft cover inside, which can ensure that no small particles enter. In the past two days, there have been many misunderstandings about N95 with exhalation valves. Some people think that there is no protective effect with exhalation valves. A study published in 2008 specifically investigated whether the exhalation valve affects the protective effect of the wearer. The conclusion is that: Whether there is an exhalation valve or not does not affect the respiratory protection of the wearer. Simply put, an N95 with an exhalation valve protects the wearer, but not the people around it. If you are a virus carrier, please choose N95 without exhalation valve, do not spread the virus. If you want to maintain a sterile environment, you can't use N95 with an exhalation valve, because the wearer may exhale bacteria or viruses. Correct wearing method of KN95 mask Ear-band wearing method Headband wearing method Ear band: Easy to wear and pick up, suitable for short time out. Headset: Closer fit, more comfortable to wear for a long time than the ear band It can be selected according to actual needs. Precautions for wearing KN95 mask 1. Wash hands before wearing a mask ? Or avoid touching the inner side of the mask to reduce the possibility of contamination of the mask. 2. Distinguish the inside and outside of the mask , up and down; that prin side of the KN95 mask is the outside; one end of the metal strip/sponge strip is the upper part of the mask. 3. Don't squeeze the mask with your hands. Including N95 mask, can only isolate the virus on the surface of the mask, if you squeeze the mask with your hands, so that the virus with droplets through the mask, there is still a chance of infection. 4. Be sure to make the mask fit the face as well as possible. 。 The simple test method is: After putting on the mask, exhale hard, and the air can not leak out from the edge of the mask. Masks are not omnipotent, but wearing masks correctly and washing hands regularly can greatly reduce the risk of infection! If you are a virus carrier, please choose N95 without exhalation valve, do not spread the virus! For the last time,3 Ply Disposable Protective Face Mask, wear a mask + wash your hands frequently, go out less, and don't go to crowded places! I hope everyone is safe and healthy! Return to Sohu to see more Responsible Editor:. zjyuan-group.com