The lung cancer epidemic of the new coronavirus infection always touches people’s hearts. Everyone is trying various ways to protect themselves. Wearing a mask as an important measure to prevent this outbreak is the focus of everyone’s attention. The medical mask science knowledge explained by Dr. Xin Wei from Case Western Reserve University in Cleveland, USA, is for your reference, so that everyone can understand how the mask is anti-virus and how to effectively prevent infection. I hope everyone can actively wear a mask.
Although there are many kinds of medical masks, they are mainly divided into two categories, general surgical masks and N95 respirator. Initially, the purpose of surgical masks was to prevent liquid splashing and prevent the person wearing the mask from transmitting germs to others, so the mask was designed so that the inner lining is matte and the outer layer is smooth. Later surgical masks were more widely used and also used to prevent infections.
N95 means that it can block 95% of bacteria. The N95 mask is a respirator, which needs to be sealed, and the air is exchanged through the mask, instead of going in and out like a mask. Therefore, the use of N95 masks needs to pass a fitting test. Speaking and deep breathing will not affect the seal. At this time, fat people have an advantage and the seal is good. 1860 is hard, generally better than the 1870 (soft) seal, but it is more uncomfortable; the better the seal, the more difficult to breathe. The N95 mask is suitable for low-intensity work, otherwise the breathing is difficult. The masks with valves are not real medical masks. They can’t be used to prevent infections. It is possible to prevent smog.
The N95 mask sounds good, but because the minimum pore size of the fiber can only be 0.3 microns, although the coronavirus is relatively large, the maximum is not more than 0.15 microns. No matter how many layers are made, it can only be delayed and cannot completely block the virus, because the virus is alive.
The MIT study found that the sneeze liquid velocity is 35m / s, and it depletes with distance. There is basically no velocity after 2 meters; it spreads in the air for about 8 meters; so if the patient is not protected, the N95 mask cannot be protected; Wearing a mask, especially the lining of N95, most of the virus is left behind. The virus that goes out has no speed, and it is impenetrable to penetrate N95 for a while. Why effective time? This is an estimate of how long a mask has virus on the surface and how long it can penetrate.
Therefore, everyone should wear a mask in public, and people infected with the virus wear masks, which is much more important than healthy people.
Viruses are not like bacteria. Viruses must have cell receptors in the body. Only the receptor cells in the body will be infected. It is reported that the receptor for Wuhan’s new coronavirus is ACE2; ACE2 receptors mainly exist in tracheal epithelium and alveoli The virus has a great effect on the respiratory system; ACE is present on all vascular epithelium, so any wound can enter.
Ebola’s receptors are on the conjunctiva, so it can pass through the eye; at least there is no scientific basis for this virus to prove that there are receptors on the conjunctiva, unless there is damage, and I don’t know how the conclusion of the eye infection comes from, unless I later prove that there are receptors on it.
Taking screenshots of two studies, one suggests that the surgeon is not as simple as wearing a face shield; the other study is that many people have used it to prove that surgical masks are as effective as N95. This research design is only suitable for normal conditions and not suitable for epidemic areas.
All in all, if you pass through the epidemic area, if other people do n’t wear masks, even if you wear three N95 masks, if everyone wears, ordinary surgical masks are enough. Wearing a leaky N95 mask is not as economical as a regular surgical mask. N95 masks also have the difference between large and small, so they can be used without being caught.
I hope everyone can put on a mask, do it for themselves and others, and work together to prevent virus infection!