As the novel coronavirus epidemic continues to spread, everyone is rushing to buy commercially available medical-grade masks. However, in fact, when the supply of masks is insufficient, many people find some old masks from home, or signs that were given away before the election. Unknown masks, but do these masks have any anti-epidemic effect? It turns out that a preliminary judgment can be made through the "air purifier" in the home.
Generally speaking, medical masks meet the CNS14774 standard, which means that under normal pressure, they can filter out 95% of bacteria. Let us first assume that the bacteria are the size of Staphylococcus aureus, which is about 1 micron. If the mask can filter out about 1 micron, you can know whether the mask meets the specifications. Three simple steps to test the effectiveness of the mask
Simply use the air purifier at home to test, because the air purifier can display the concentration of PM2.5 micron particles. In theory, the air passing through the mask can reduce the PM2.5 The value can be effectively reduced.
Step 1:
Find the place where the air purifier detects the air. Most of them are on the back of the machine. There will be a small fan inside to suck the air in.
Step 2:
Cover the detector with a mask and seal it with tape around it.
Step 3:
Light the incense stick and wait at the air detection port for about 30 seconds. Use your hands to block the smoke from gathering in the air detection area. If the mask is ineffective, you can find that the air purifier value keeps rising.
The results show:
Generally, the value of three-layer masks continues to soar, but if a medical-grade three-layer mask is used, the value drops significantly. As long as it complies with medical regulations, the value will be within a certain dozen, and if it has no medical effect, the value will exceed 100. In a simple way, you can know at home whether the mask you are wearing has a protective effect!
If you don’t have an air purifier at home, you can also use a mobile air quality monitor. However, the scientific platform also emphasized that masks cannot filter out viruses, but can only filter out droplets. However, viruses are transmitted through droplets. In addition to wearing a mask, washing hands frequently is also the only way.
This detection method is non-academic and will vary according to different devices, but it can be easily operated by the general public.
Articles, videos/excerpts compiled from LIS situational science textbooks