Are there really “anti-virus” cars during the COVID-19 epidemic?

It’s too difficult. The start of 2020 is really difficult. The spread of the new coronavirus epidemic has brought all domestic industries to a state of shutdown, and the automotive industry is also facing a huge test. In the face of the epidemic, in addition to donating money, some car companies have also taken practical actions to actively transform and open mask production lines. Some car companies have taken advantage of the situation to launch "N95 mask-level" mass-produced vehicles. What is going on? Woolen cloth?

Geely’s “N95 Mask Production Vehicle”

The first one is of course the “Vehicle-mounted N95 Mask Production Vehicle” launched by Geely in response to the epidemic. Of course, this is not a car, but a newly developed IAPS vehicle purification system that can meet N95 mask-level standards. The first batch of systems that meet mass production standards will be installed on 150 Geely Jiajis.

Of course, the power system of this mask version of Geely Jiaji is no different from that of the regular version. The special feature is the upgraded air-conditioning filter element. According to Geely, the system will adopt N95 mask filtration standards and use high-efficiency composite air-conditioning filters to intelligently and quickly purify the air in the car. In addition to conventional step-by-step filtration of dust, harmful gases, PM2.5 particles, etc., it will also filter particles with a particle size of 0.3 microns and above. The dust filtration efficiency reaches more than 95%. Especially for droplets with a diameter usually greater than 0.74 microns, which the new coronavirus often adheres to, it has a better filtration effect, achieving an "N95 mask-level" purification effect.

This is the truth, but in reality, the problem cannot be seen this way. When a person sneezes, he can spray 100,000 saliva droplets at a time, which can spread in the air at a speed of 145km/h. The range is about 2 meters, and most of the aerosol particles containing germs are concentrated at about 1 meter, which is also the recognized disease-causing and infectious area. If the droplets are smaller, they have a larger range and remain suspended in the air as aerosols.

The great thing about the Jiaji air purification function is the filtration effect of the air-conditioning filter. Therefore, its filtration of the environment outside the car is naturally stronger than that of the ordinary version. Although the speed of droplets may be extremely fast, there should be no He might sneeze into the air intake outside the car. However, this is only good for isolating outside the car. Suppose there is a patient in the car, he carries the virus, and he sneezes. At this time, the droplets will fly in the car at an extremely fast speed. At this time, he is in front of the co-pilot. The air conditioning filter has no filtering effect in a short period of time. And the droplets will stick to car windows, seats, etc. You can imagine what will happen next.

So this function is useless? Of course you can't say that. After all, the Internet of Vehicles is so developed that remote purification is not a problem. Geely Jiaji has this function. Through the mobile APP, you can pre-start the vehicle and turn on the air conditioner for filtering. However, I wonder if the "mask version" Jiaji has settings in the APP to increase the air volume of the air conditioner to improve purification efficiency. One more reminder, if there are other passengers in the car besides the driver, please wear a mask.

Roewe's "N99 level" protection/MG's "triple protection"

Recently, Roewe Motors also issued a promotional slogan, claiming that all mainstream models are covered with "N99 level" protection, and MG The slogan "triple protection" is also used. What's going on?

In fact, both Roewe and MG have already equipped their models with "N95-level" air-conditioning filters. The filter material of this filter is composed of a pre-filter layer of spunbond process and an ultra-fine filter layer of melt-blown process. It is composed of fiber layers and is made through an electrostatic electret process. It not only has a mechanical blocking effect, but also can capture bacteria, dust, etc. for a second time. It is said to be able to filter more than 95% of droplets carrying coronavirus. Seeing this, it is actually somewhat similar to the Geely Jiaji we just talked about. We definitely don’t have to worry about the filtration of the air outside the car, but what about inside the car? Roewe also has a second line of defense, a negative ion generator and an independent air purifier. According to Roewe official introduction, the negative ion generator can quickly reduce bacteria in the air within an hour, with a sterilization rate of >85%; the air purifier is antibacterial and anti-allergic. The antibacterial rate of the functional layer exceeds 99% within 24 hours.

It looks really powerful. The dust removal principle of the negative ion generator is to use high-voltage corona to increase the negative ion component in the air, and the negative ions will absorb fine dust and settle to the ground. Among them, the ones that can absorb viruses are small-particle negative ions. This kind of negative ions is also closest to the negative ions in nature and is also called "ecological-grade negative ions."

The authoritative book "Environment, Health and Negative Oxygen Ions" in the field of negative ions clearly states that when the concentration of negative ions in the indoor air reaches 20,000 per cubic centimeter, the amount of floating dust in the air will be reduced by more than 98%. In the air containing high concentrations of small particle size negative ions, the most harmful dust particles, bacteria, viruses, etc. with a diameter of less than 1 micron in PM2.5 are almost zero.

Then if you drive the negative ion generator in your Roewe car, wouldn’t it mean that there is no virus?

The reality is very skinny. Negative ions can be divided into three types according to their size: large, medium and small. Small-sized negative ions that can absorb viruses require a generator that can produce small-sized negative ions. Yes, they only absorb. ,settlement. What really sterilizes is that it produces a large amount of negative ions while also producing trace amounts of ozone. The combination of the two makes it easier to absorb various viruses and bacteria, causing them to undergo structural changes or energy transfer, leading to their death. As for how powerful the negative ion generator in the Roewe car is, I really want to try it.

▲The air purifier at the armrest box

Roewe MG’s third line of defense is service. Simply put, it provides after-sales in-car sterilization and disinfection services, using ultraviolet lamps and high-temperature sterilization , and then clean it up with a purifier. I still agree with this line of defense. Regardless of whether it is a publicity stunt or not, being able to remotely activate the air conditioner, filter, negative ion generator, and purifier through a mobile phone APP before using the car can indeed make the car cleaner!

Volvo

The CLEANZONE? system is Volvo’s complete solution for cleaning the cabin, including interior air, non-sensitive contact materials, interior emissions and new car odor. Among them, the standard IAQS intelligent circulation system can identify harmful substances in the air. When there are odors or harmful substances outside the car, it will automatically start internal circulation; the standard active cabin purification system will automatically activate the air-conditioning system when the owner unlocks the vehicle remotely. Ventilate the car for one minute; the enhanced activated carbon air conditioning filter element, in addition to effectively filtering PM2.5, can also filter PM0.4, which is particles with a diameter of less than or equal to 0.4 microns.

On mid-to-high-end models, the Volvo S60 is also equipped with a dual-effect enhanced air purification system (AAC). This system was developed as early as 2014. It uses a negative ion generator to block up to 95% of PM2.5 particulate matter through electrostatic adsorption and air conditioning filters under specific usage environments and conditions.

Volvo CLEANZONE? This independent in-car purification system certainly has better filtration efficiency and effect on the air in the cabin than filtering through the on-board air conditioning system alone. In fact, similar configurations can be seen on many domestically produced models, but most of them just have an extra air conditioning filter element.

Tesla Model? S/X

Tesla’s biochemical defense mode sounds particularly resistant to viruses. Is this true?

In fact, to put it simply, this defense mode is mainly based on the HEPA (High Efficiency Particulate Air Filter) air conditioning filter element. The air conditioning filter element in the Model? S/X car has a huge area, and it uses a HEPA filter element. This filter element has a filtration effect of 99.97% for particles in the air with a diameter of 0.3 microns. This level is more than enough to filter PM2.5, and it can resist most bacteria, pollen and dust.

▲Two-layer air conditioning filter element on Model? An appropriate amount of positive pressure is established inside the vehicle to prevent air from outside the vehicle from entering the vehicle. In theory, it can resist biochemical attacks from outside the vehicle. In fact, this working principle is also applied to other brands, but Tesla designed the air conditioning filter element to be larger, and designed the cabin sealing and details to be more perfect.

Similarly, the HEPA filter element of Model? S/X plus the "biochemical defense mode" has good adsorption and isolation for droplets larger than 0.74 microns that viruses often attach to.

So, can the cars mentioned above be able to withstand the new coronavirus?

NO! !

The reason is that viruses are much smaller than bacteria. According to the fourth edition of the "Diagnosis and Treatment Plan for Pneumonia Infected by New Coronavirus" issued by the state, the new coronavirus belongs to the genus β and has Coated, the particles are round or oval, often polymorphous, with a diameter of 60-140nm, which is 0.06-0.14 microns. Therefore, even though HEPA filters and biochemical defense modes are used, they cannot truly effectively filter viruses. And if you are in a car, you will have the opportunity to come into direct contact with objects in the car. If there is a virus carrier among the passengers, you will also be at risk of being infected.

So, if you really need to drive out in an emergency, what should you do?

1. If there are other passengers in the car, remember to wear a mask. You are not only responsible for yourself, but also for others;

2. Do a good job of disinfection, if possible Use 75% alcohol to wipe your hands and wipe door handles, trunk switches, one-button starters, cup holders and other frequently touched places. However, it should be noted that the locations of leather fabrics and chrome-plated materials cannot be wiped directly with alcohol or disinfectant;

3. When the environment outside the car is good, remember to open the windows for ventilation and enhance air circulation. In crowded places, or in parking lots, underground garages, etc., it is recommended to close the windows and turn on the internal circulation of the air conditioner.

4. Pay attention to controlling the temperature of the air conditioner. Although the new coronavirus is relatively sensitive to heat and can be eliminated at 56 degrees in 30 minutes, it is obviously impossible to achieve it in the car. The method of using heating to reduce virus activity has not been proven. What's more, if the temperature difference between the inside and outside of the car is too large, it can easily lead to colds, so just adjust the temperature to a suitable temperature.

So, during this special period, if there is nothing urgent, it is better to actively respond to the country’s call and stay at home. Finally, I wish all netizens to take good care of themselves, enhance their resistance, maintain a good attitude during this special period, and refrain from gathering, dining, partying, spreading rumors, believing rumors, or spreading rumors until the epidemic is over. It’s when spring comes and flowers bloom.

This article comes from the author of Autohome Chejiahao and does not represent the views and positions of Autohome.