Masks, as a common hygiene product in our lives, are widely used in medical, environmental protection, and even personal dress up. Recently, the mask frequently boarded the hot search, has become the hearts of the public “hot goods.” But there is no denying that there are still many people on the street who do not wear the mask properly, do not wear the right mask, do not even know how to disinfect the mask every time it is used up or should throw away for a new one? Here, we strive to through an article, to science and technology to take a look at this “little thing”, tell everyone what to know.
From animal bladders to N95, mask development is a life-saving history in the West
The world’s first use of masks or record the use of “type mask” products is China.
In ancient times, people in the palace in order to prevent dust and breath pollution and began to cover the mouth and nose with silk scarves, such as “courtesy dredging” said: “cover the mouth, fear of breath touch people.” “It’s unhygienic to cover your nose with your hands or sleeves, and it’s not convenient to do anything else, and then someone uses a cloth to cover their mouths and noses.
In the first century AD, the Western philosopher and naturalist, Old Pliny (also associated with a diamond brand), used loose animal bladder skin to cover his nose to filter out dust to avoid inhaling the toxic mercury sulphide when it was crushed.
It can be seen that, although the East and West “mask” form is more crude and random, but more or less to meet the user’s needs. At this time, “mask” is not civilian, but has become the “court” and “celebrity” exclusive.
Later, with the deepening of microbial research in Western medicine and the scientific community, masks were further developed.
In 1876, the German surgical physician Mikuriz proposed that medical personnel should wear a sterilizing gauze mask that covers the mouth and nose to prevent bacterial infection, known as the Mikriz mask, the first medical mask in modern history.
However, the mask was also very simple, just with one or a few layers of gauze to simply wrap the face compactly, convenience and comfort and real modern mask gap.
In addition to Western scholars, in the course of the development of masks, there is a Chinese also made an indelible contribution – he is a pioneer of modern Chinese medicine, China’s quarantine, epidemic prevention cause founder Wu Liande.
In December 1910, pneumonic plague became endemic in the Northeast. The epidemic spread rapidly, with 39,679 deaths in Jilin and Heilongjiang provinces, accounting for 1.7% of the population of the two provinces at the time, especially in The Harbin area.
At the end of the Qing Dynasty, the Qing government did not have a special epidemic prevention agency. Forced by the situation, the Qing government sent Woolende as the plenipotentiary general medical officer to the northeast to lead the epidemic prevention work.
During this time, in order to stop the spread of the plague droplets, Woolende invented a mask made of two layers of gauze, known as the “Wood mask” mask is simple to make, easy to obtain materials, low production costs, so widely distributed.
In the severe situation of the epidemic at that time, less than four months to put out the shock of the plague epidemic in China and abroad. The Wu’s mask also became the first mask to be used in public vaccination.
If masks had previously been used mainly in the field of health care, then it would have been the “Spanish flu” of the early 20th century that was widely used by ordinary people as a product of mass life.
The pandemic spread through the war to Europe’s World War I battlefield and then swept the globe, killing 50 million people, more than the total number of wars in World War I and World War II. Masks became a national necessity during the flu epidemic, and people from all countries are required to wear them in order to combat the outbreak. For example, on the bus, without a mask can not go on!
Since then, the large-scale use of masks is significantly frequent, in the history of the history of influenza, masks in the prevention and blocking of the spread of bacteria several times play an important role. Such as SARS …
The principle of the function of mask: cut off the transmission of the virus
From the current public situation, the recent epidemic of the virus has three main ways of transmission, its main spread is the spread of droplets, the virus can be closely through coughing, sneezing, conversation discharge of secretions and droplets by the inhaler inhalation and infection.
It is understood that under normal circumstances, people’s lungs will have about 1 liter of liquid, each time a sneeze, the lungs will be like a crushed bottle of mineral water sprayed out of the liquid in fog. When they are in vitro, they are divided into more than 40,000 small droplets, each containing a large number of viruses and bacteria.
Due to the effects of huge thrust in the body, these liquids can reach speeds of up to 35 m/s and travel distances of 3 to 8 meters.
At this point, the role of the mask will appear! The multi-layered structure of the mask effectively blocks large particles, which in turn are adsorbed to the internal fibers because of the electrostatic effect. That is, the sick wear a mask, coughing droplets (with viruses) will be blocked by the mask, to prevent infection of others. Healthy people wear masks that can block their own droplets (with viruses) that can be called into others.
Not all masks can withstand the “attack” of droplets.
Because the mask is widely used in various fields, therefore, all areas will have their corresponding masks, rather than a mask can be worn. The following are not recommended for use.
1, star with sponge material mask
Common in airports – star low-key appearance essential. Little sister go out too late to make up, wear this kind of mask still hold half-mask, but also has a certain dust protection effect, but for virus protection is not recommended, sponge existence of a number of large gaps are very easy to adsorption and viruses, the risk is very high.
2, ordinary cotton mask
Most commonly seen in the northern friends in the winter, or some sanitation workers used to block wind and sand, such masks are used to prevent large particles of dust and keep warm, for the barrier droplets and viruses also do little.
3, and ta.
DIY “anti-virus mask” – only left in a friend’s circle.
Why do people prefer the N95?
The self-media paper clip indicates that if we use the diameter of the particles as horizontal coordinates and the filtration efficiency as the ordinate, the filtering effect of these masks is actually a U-shaped curve. As you can see, the most difficult to filter is actually particles about 0.3 microns in diameter.
This is why most masks use 0.3 micron sodium chloride filtration capacity as a test indicator, which filters more than 95% of the N95 in tests. So what’s so special about the N95?
First, it’s important to note that the N95 is not a specific product name, but a standard, and a product that is reviewed by the National Institute of Occupational Safety and Health (NIOSH) can be called an “N95 mask.”
At present, although China’s daily production of masks more than 10 million, but the N95 medical protective mask son mask daily production capacity of only 600,000. Experts call for the best possible protection of the epidemic prevention and control of the first-line medical staff use.
It is understood that compared to the production process of disposable masks is simple, the production process of N95 masks is much more complex, and there are certain requirements for technology.
Earlier, Southern Weekend pointed out that, for example, a company that specializes in making KN95 masks could take up to a year to produce 40 million KN95 masks. Due to the effective management of the environment in recent years, the mask industry is not depressed, the whole industry is in the production capacity stage, many manufacturers do not have too many mask reserves, now can sell is also a small amount of inventory.
Fortunately, studies have shown that the vast majority of droplet nuclei are concentrated between 0.74um-2.12um, so even ordinary medical masks can capture the vast majority of particles. So, we can not go out without going out, can not use N95 without N95 !!!
How do I choose a mask?
Nowadays, in the e-commerce platform, the mask is also a rush, so how to choose the appropriate mask? Here are three things to share.
1, check the seller’s business qualifications
Social platform has been organized by netizens nearly a hundred dishonest business stores, most belong to the medical device sales qualification, and this kind of is also easy to trample, offline purchase is also recommended to relatively well-known pharmacies.
2, check the manufacturer
Through the manufacturers of packaging, enter the medical device column under the State Drug Administration for query and check.
3, look at the outer packaging logo
China’s medical masks belong to class II medical devices, management is also more stringent, manufacturers factory medical masks need to be labeled “production license number”, “product registration number”, “product technical requirements number”, so there is no such information as a medical mask to pay attention. Seller no problem, manufacturer no problem, and then compare the purchase of the product technical requirements number is in line with the corresponding standards of the product described above, you can judge whether they bought the mask is the right one.
So, how do you wear the mask correctly?
Choosing the right mask is important, but it’s more important to wear it right. Proper wear can be divided into four steps.
Step 1: Clear the front and back. Masks are divided into fronts and backs, upper and lower, the front (outward) is mostly light blue or dark, the opposite side (facing inwards) is mostly white or light color.
Step 2: Wash your hands. Wash your hands before wearing a mask, because the mask is relatively sterile, and if your hands are dirty, touch the mask, and you will put dirt on your hands on the mask. (Wash your hands after taking off your mask)
Step 3: Put it on. Make sure that the mask is facing inwards, with one end of the metal bar facing up, and the rope sits on the ears at both ends.
Step 4: Press and stretch. Press the metal bars on both sides of the nose bridge with both hands so that the upper end of the mask is close to the nose bridge, and then stretch the mask down so that the mask does not leave wrinkles, better covering the nose and mouth. If the comparison is not tight to create a gap, then the droplets may be through the gap infection, such as a head higher than you, you accidentally sneezed. For details, refer to the droplet propagation diagram.
What about the mask after use?
In the N95 mask is a large number of purchase, use at the same time, the use of the back mask how to deal with the spread of pneumonia has become a new problem. We can use a picture of CCTV News to learn how to deal with used masks.
Finally, don’t forget to wash your hands.
Whether it’s wearing a mask, removing a mask, or doing something else, it needs to be done by hand. Most importantly, wash your hands because you may well have a live coronavirus on your hands.
In the case of SARS viruses, experts say they can survive on glass, plastic and metal for at least two days, and they stay in various places with droplets, and your hand is likely to be touched. When you rub your eyes and suck your fingers, the virus comes into contact with mucous membrane cells and completes the infection. Therefore, wash your hands frequently at home and wash your hands more often.
It can be seen that the mask is not only a barrier to protect people from germs, but also a witness to the struggle of humans against germs.
The wheel of history rolling forward, we have overcome many major disasters, this time must also be!
Come on! Final tip: can not go out do not go out! Can not use N95 without N95! Wash your hands more!