Function of disposable protective face mask：
Layer of disposable protective face mask：
1.Outer non-woven fabric : effectively blocking visible objects such as droplets
2.Medium meltblown layer : filtering fine particles, low breathing resistance
3.Inner non-woven fabric : skin-friendly material, non-irritating, absorbs the hot air exhaled from the body
Nose bridge clip of disposable protective face mask：
After wearing, press the nose clip and adjust the fit at will to prevent particles from seeping into the gap
Moderate elasticity, allowing ears to feel free
360 ° three-dimensional breathing space with a larger protective area
Reticulated structure, more firm and not easy to fall off
Precautions for wearing disposable masks
Generally used disposable mask materials (below N95) on the market have an efficiency of 13-92% and a penetration rate of 8-87% at 0.3 μ m, that is to say, the performance of disposable masks on the market is very different, which can be said that the quality is more than 10 times (87 / 8 >10) The international standards for high-efficiency disposable masks are very complete, but for daily disposable masks, the standards need to be strengthened, especially in case of epidemic.
The tightness of disposable masks is very important
When wearing masks, pay special attention to sealing. If the sealing is not good, the effect of filtering bacteria and viruses will be greatly reduced. Especially for medical staff, they need to wear more efficient disposable masks (above N95, R, P grade). Take N95 disposable masks as an example, many N95 disposable masks have an efficiency of more than 99% at 0.3 μ m (penetration rate < 1%), Even if there is only a small amount of air leakage, for example, 3%, it means that the protection force is greatly reduced. Compared with 1% penetration rate, there is a difference of at least three times. If there is air leakage in daily wearing of mask, it will be more than 3%. In advanced countries, for the staff working in the environment with severe infectious patients, they need to pass the sealing test after wearing the disposable mask to make sure that they have enough protection force before entering the medical institutions and wards. High efficiency disposable mask, although high efficiency, has high resistance to inhalation. Sometimes it is difficult to wear it for a long time, especially for people with poor cardiopulmonary function. Therefore, people who work in the dangerous area of infectious patients will directly wear a full-scale gas mask with pump (battery operated) and 100% efficiency filter tank, because the filtered air is put into the mask, It's positive pressure. It won't cause breathing difficulties. In addition, it can prevent the virus from entering the human body from other organs (such as eyes and nose). It is also important to remember that wearing a mask is not a form, but a protection. Without this layer of protection, the consequences may be very serious. If there is medical tape, it can be used to stick the tape on the place where disposable mask and face contact to reduce air leakage.
Selection of disposable masks
There are many kinds of disposable masks on the market, and the classification is also very complex. When the supply of various disposable masks is sufficient, they can be worn by category. But if the supply is insufficient, the focus will be on wearing masks instead of masks.
N95 disposable mask has high efficiency, but it is not necessary due to large suction resistance. Disposable masks below N95 can be selected. But when the medical staff work in the polluted environment, they can choose N95 or even full-scale gas masks on the premise that their bodies can bear the load.
Is there any difference between stereo disposable mask and plane disposable mask?
The answer is: Yes, the tightness of the three-dimensional mask is better than that of the plane mask. In addition, the efficiency of electrostatic cotton in disposable respirator is sensitive to the face velocity of the gas. With the increase of the face velocity, the time for the aerosol to pass through the filter material will be reduced, so the attraction of electrostatic field to the aerosol in electrostatic cotton will also be reduced, and the filtration efficiency will be reduced, which means the protection ability will be reduced. Generally speaking, the inspiratory capacity of human respiration is about 5-8 LPM (liter / min), and the capacity of one inspiratory and expiratory is about 500 cc. Relatively speaking, but not absolutely. The usable filter material area of the three-dimensional mask is larger and more uniform than that of the plane disposable mask. The effective filter area of the plane mask is mostly limited near the mouth and nose, especially under the nose. The surface velocity of the local area will be higher when inhaled, so the average filter effect and efficiency may not be as high as that of the three-dimensional disposable mask.
The service life of disposable mask
When the supply is sufficient, use it according to the instructions, but in the current situation that the supply of disposable masks is in short supply and there is epidemic situation, the problem of prolonging the use time is generally not big. As for the length of prolonging the use time, it depends on the time of wearing disposable masks every day, the concentration of aerosols in the environment and the supply of disposable masks. The premise is to wear a mask at one time.
Generally, if you are not working in a high-risk environment, there is no problem with a disposable mask for 3-5 days. After all, epidemic prevention materials should be left to the people who need them most.
The frequency of changing masks may be higher than usual. This is why the front-line medical staff must have sufficient protective equipment.
In TV or daily life, it's helpful to see someone wearing several layers of disposable masks. The answer is true! If there are several layers of materials in the filter material of the air screening program, the calculation formula of efficiency is ptotal = P1 * P2 * P3, where p is the penetration rate, and someone wearing two layers of disposable masks, the efficiency of the first layer is 40% at 0.3 μ M (the penetration rate is 60% = 0.6), the efficiency of the second layer is 70% (the penetration rate is 30% = 0.3), the total penetration rate of the two layers is 0.3 * 0.6 = 0.18 (18%), the efficiency can be increased to 82%, but the suction resistance will also increase (the sum of the two). When there is no efficient screening program, and the environment needs efficient screening program, this is a way to solve the problem.