This article mainly introduces the KN95 air valve, like the anti-smog mask, there is a breathing valve switch like a button, the design of the breathing valve is one-way air out, and there are several layers of flaps on it.
When you buy masks recently, you will find that KN95 masks/N95 masks are divided into two types: with breathing valve and without breathing valve. Why do masks have breathing valves? If mask wearers, people with chronic respiratory diseases, heart diseases or other diseases accompanied by breathing difficulties, use KN95 masks/N95 masks, it may make it more difficult for the wearers to breathe. why? We know that KN95 or N95 masks have a relatively high level of protection. It can be understood that this type of mask with good protection effect is thicker, so the breathing force needs to be stronger than ordinary masks. Therefore, the use of the KN95 air valve can make their exhalation easier and help reduce heat build-up.
When inhaling, the mouth cover will be closed tightly. At this time, the air inhaled by the wearer enters through the mask, that is, the air is filtered through the mask before entering the human body. At this time, the mouth cover is closed to ensure that no particles enter.
When exhaling, the mouth cover will open. At this time, the air exhaled by the wearer passes through the exhaust port, allowing the hot and humid air to escape. At this time, the exhausted air is not filtered by the mask. In the figure below, the function of the breathing valve can also be clearly seen.
Some people may think that the effect of KN95 air valve is better and the protection effect is better. The fact is, the same, whether a mask has a breathing valve or not can protect the wearer. The difference is that the N95 with an exhalation valve can protect the wearer, but because the breathing valve mentioned above is a one-way design, the gas exhaled by the wearer is not filtered, and the droplets or germs and viruses exhaled by the wearer will pass through the breathing valve To the surroundings, so the mask with breathing valve only protects the wearer but not the people around. Mainly used in industrial dust masks and anti-smog (PM2.5) masks, not suitable for medical institutions. If you are a virus carrier, please use N95 without an exhalation valve and do not spread the virus. At the same time, readers are reminded that if you see a confirmed patient wearing a mask with a breathing valve, readers should be careful!
You can watch the news program, you will find that the front-line doctors and nurses wear masks without breathing valves. Therefore, for medical use, they do not have breathing valves. Only civilians have breathing valves.