Now, the most commonly worn mask is this disposable medical mask
. The price of this mask is relatively affordable, and a mask is only about one yuan. First of all, when we buy a mask, we need to look at the outer packaging of the mask to see if it is a disposable medical mask. If it is some other disposable dust masks and thermal masks, these masks cannot isolate bacteria when worn. role, this should be remembered.
Next, let's take a look at the production date on the outer packaging of the disposable mask, as well as the date of expiration. The two dates are exactly two years apart, which means that the medical disposable mask that Xiaobian bought, it The shelf life of the mask is two years, and it is still within the validity period. As long as we use the mask within the validity period of the mask, this kind of mask can give us a good protection effect.
Then, let's take a look at the internal structure of the mask. We use scissors to cut off one side of the mask. Generally, this disposable medical mask has three layers of cloth inside, one in the front and one in the middle, and three layers in total. Cloth, with this three-layer structure, can filter and isolate bacteria when we wear it. And if the inside of the mask we buy has only two layers, then it is best not to wear such a mask.
We can do a small experiment to see the effect of the comparison. We poured some water into the disposable medical mask. Let's see that after pouring in the clean water, the water inside did not penetrate into the bottom, which means that this kind of three Layered disposable medical masks, the isolation effect is still very good.
Next, we tore off the middle layer of the mask, and now we pour some water into the mask, we can find that the water inside will slowly penetrate, so if your disposable mask The internal structure has only two layers. Without the isolation filter layer in the middle, it will not be able to isolate bacteria. Therefore, it is best not to wear two-layer disposable masks.
After reading the above little common sense about disposable masks, I believe you have understood that when we buy masks, we must buy disposable medical masks. Also remember to check the production date and expiration date of the mask, and do not use expired disposable masks. If the internal structure of the mask is only two layers, without the isolation filter layer in the middle, it is best not to wear it.
EN149:2001+A1:2009 FFP2 NR
Filtration efficiency ≥ 94%
Effectively block dust, smoke, fog and microorganisms
Better air tightness, easy to carry with