TU-TESL

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With the development of the epidemic, the management and control measures are becoming more and more strict. Wearing masks has become a new daily code of conduct. How to prevent and control the epidemic when driving out as little as possible as a private car? As mentioned in the last article, many brands of passenger cars are equipped with air purification devices as standard, which to a certain extent is equivalent to the "Mask" of private cars. However, generally speaking, the vehicle air purifier is not completely isolated from the virus. On the one hand, we need to understand the transmission mode of the virus. At present, there are three officially determined transmission channels, one is spray, the other is aerosol, and the third is contact, which is why we must wear masks and wash hands frequently. Second, we need to understand the working principle of automobile air purifier, which can filter and purify. Generally speaking, vehicle air purification device includes anion generator, breeze fan, air filter device, etc. The breeze fan can make the air in the car circulate and flow. After the air in the car is filtered by PM2.5 filter screen and active carbon filter element in the air filter, it will generate ionization through the negative ion generator, and then generate negative ions, which will be sent out by the micro fan to achieve the purpose of air purification. In this process, most of the dust, particles, formaldehyde, benzene and other harmful substances in the air will be removed. It should be noted that the second major route of transmission of the virus causing this epidemic is aerosol, which is a combination of virus carrying droplets and floating dust in the air. According to the working principle of vehicle mounted air purifier, aerosol can be effectively filtered and isolated, which can greatly reduce the breeding and transmission of the virus in the vehicle. In fact, the air conditioning filter element of the car can also be used as a kind of vehicle air purification device. Someone will say: my car has no air purifier, can I clean the virus by relying on the air conditioning filter element? It depends on what type of filter element you have. Generally speaking, the common filter paper type filter element or active carbon filter element of the air conditioner filter element of most common models can filter large dust and pollen, etc., and the effective filter element can also absorb and filter foreign matters and peculiar smell with a diameter greater than 10 microns, but the two filter elements have no good effect on viruses. There is also a more advanced HEPA filter element. Some middle and high-end models will use this air conditioning filter element, such as Volvo S60. According to the data, DOE American energy has set the standard of HEPA filter element, that is to say, the filtering efficiency of 0.3 μ m dust particles should be over 99.97%. In other words, HEPA filter element can effectively filter the air carrying virus. HEPA is very powerful. In fact, it is divided into many levels. The higher the level, the better the filtering effect. As shown in the figure below, when the level is E11, it will have the same effect as our N95 mask. The higher the level, the better the filtering effect, of course, the greater the power consumption. Here we recommend several HEPA filter elements for you. If you want to change your car, you can refer to them, including man brand, Mahler, Bosch, etc. In fact, the on-board air purification device is mostly used for daily air purification. In the face of virus, it can not absolutely guarantee the killing effect, especially for the air purifier that has been used for a long time. Because the filter element absorbs too much dust and harmful substances, the effect will be greatly reduced. Therefore, if the air quality outside the vehicle is good, it does not pass through the area where people gather (this time It's hard to meet the place where people gather). Then, it's still necessary to open windows and ventilate every other period of time. It's afraid of cold. You can start the external circulation to ensure the fresh air in the car. For virus prevention, the most important thing or outside the car, whether it's droplets or aerosols, are easy to produce and contact in areas where people are easy to gather (such as food market, supermarket, etc.), so masks are essential! Masks are essential! Masks are essential! Important things are to be repeated for 3 times. Once out, back in the car, remember to disinfect your hands. Some people say that they can't wash their hands when getting off the car. First, they can disinfect their hands with hands free disinfectant. Second, they can cut cotton gloves. Experts say the virus has a short life span in rough objects. If possible, spray atomized disinfectant, including 75% alcohol, into the car. However, it should be noted that chlorine containing disinfectant will corrode the leather surface, and it is not suitable to spray directly on the seats and other places. Back home, the best way is to use alcohol, or disinfectant wipes to wipe the steering wheel and other places where the hands have been in contact with the car, and then the car is best left standing for a period of time, so that the virus that may be left in the car will die.