The longer commuting time means that people spend more time in the car. Data show that about 90% of people's life is spent in semi-enclosed space, of which indoor space accounts for 5.5%. According to the age of 80, there are 29,200 days in life, and the time spent in the car is about 1445 days.
People stay in semi-enclosed space for a long time, and air quality becomes an important factor affecting health. In fact, for a long time, the number of complaints about the air quality inside the car has been high. As of 20 19, 12, 17, the cumulative number of complaints about the odor inside the train reached 10059, ranking 11th in the list of network failures of train quality.
In recent years, consumers have almost realized that the taste changes color, but the smell inside the car and the air quality inside the car are two different concepts. Some pollutants will be perceived by the occupants in the car in the form of odor, but many pollutants are colorless and tasteless, which can be described as "invisible killers" in the car.
What should I pay attention to in-car air quality?
The interior environment of a car is composed of roof, door trim, seats and other structures and interior decorations. With the function of air conditioning equipment, the climate inside the car is different from that outside the car. The air quality inside the car is affected by many factors, which are mainly divided into four parts at present:
1, air pollution outside the vehicle: pollutants such as smoke, hydrogen sulfide and inhalable particles in the atmospheric environment will enter the vehicle through the air outlet;
2. Engine combustion products: the gas generated by engine combustion will enter the car through the gaps and seams of the car body;
3. Volatile organic compounds in the car: harmful gases released by automobile interior materials;
4. Bacteria in the car: Because the condenser part of the automobile air conditioning system is humid, it is easy to breed bacteria, and internal circulation may lead to the spread of bacteria in the car.
Although there are various sources of automobile air pollution, at present, the standards for evaluating indoor air quality in countries all over the world mainly target at volatile organic compounds (VOC), and focus on controlling eight substances, namely benzene, toluene, xylene, styrene, ethylbenzene, formaldehyde, acetaldehyde and acrolein.
Taking formaldehyde as an example, when its concentration is greater than 0.08 mg/m3, it will cause jealousy, throat discomfort and other symptoms; When the concentration exceeds 0. 1 mg/m3, the eyes and mucosal cells will be damaged. When the content reaches 30 mg/m3, people will die immediately. Even if the formaldehyde content in the environment is low, if it is exposed to the environment for a long time, it will cause serious diseases such as chronic respiratory diseases, nasopharyngeal carcinoma and leukemia. These eight substances, which are called "pentaphenyltrialdehyde", have high content and frequency in automobiles and are highly toxic, so they have become the key control objects.
What is the standard for judging VOC in the car?
At present, many countries have formulated relevant standards, among which KOR is the national standard of South Korea and JAMA is the independent action plan of Japan? The new version of the domestic standards office is still in the stage of soliciting opinions.
Compared with Korean and Japanese, China's standards are quite high. For example, in the process of car inspection, South Korea only needs to close the door for 2 hours, while in China it is 16 hours. The longer the vehicle is closed, the higher the concentration of volatile harmful substances in the vehicle.
Unfortunately, GB/T27630-20 1 1 "Guidelines for the Evaluation of Air Quality in Passenger Cars" is only instructive, suggestive and not mandatory, which also causes the dilemma of consumers.
How to do a good job of VOC protection in the car?
The VOC in the car mainly comes from parts and interior materials. To reduce the VOC in the car, car companies need to meet GB/T? 27630-20 1 1 limit index, set the VOC emission control target of the vehicle. However, the national standard is not mandatory, so consumers can't know whether the VOC content of a car is qualified, and the VOC detection equipment requires high standards, involving ion chromatography and reflection interference spectrometry, which is too expensive for ordinary users.
Based on the awakening of consumers' awareness of automobile health, China Automobile Research Institute initiated and dominated the research resources of automobile industry, medical industry and communication industry. Evaluation of China Automobile Health Index. At present, the automobile health index of China mainly aims at volatile organic compounds (VOC), odor (VOI) and electromagnetic radiation (EMR) in the car, and will also include the assessment of particulate matter (PM) and sensitization risk (VAR) in the later period.
At present, China Automobile Health Index has evaluated 28 models. Through the score, consumers can directly judge whether the VOC content of a car is qualified, whether the odor inside the car is strong, and whether the electromagnetic radiation inside the car exceeds the standard. In the future, China automobile health index will actively carry out evaluation and expand the evaluation dimension, and strive to provide consumers with a broader and more comprehensive reference.
In addition to buying healthy models, consumers can also reduce the VOC content in the car through some techniques.
Although many people will recommend products such as activated carbon, photocatalyst and negative ion purification, the effects of these black technologies are often very limited. For example, activated carbon belongs to passive physical adsorption, formaldehyde is its prey, and activated carbon is a trap without bait and can only be trapped by prey.
In fact, ventilation is an effective way to reduce VOC in the car. Some studies have found that good ventilation helps to reduce VOC content, and after 30 minutes of ventilation, VOC content will be significantly reduced. At the same time, there are also experimental data showing that the concentration of VOC in the car will increase with the increase of temperature. Is the boiling point of formaldehyde 19? Above 29 degrees Celsius, formaldehyde volatilizes faster.
The new car can accelerate VOC volatilization through high temperature exposure, and then effectively remove VOC in the car by ventilation. It should be noted that old cars are not suitable for exposure. Because with the passage of time, the VOC in the car will gradually decrease and reach a stable state, but exposure to the sun is very likely to make the originally stable materials emit harmful substances again, and the car will also accelerate aging.
Therefore, in daily use, it is necessary to open more windows for ventilation, and at the same time try to avoid entering the carriage at high temperature.
Under the epidemic environment, the requirements for automobile air filtration system are becoming more and more strict, but the concern about the air quality in the car should not stop there, and the VOC and VOI in the car should also be the focus of attention. Now people spend more and more time in the car, and the air quality inside the car can not be ignored.
This issue of automobile health clinic mainly explains the harm of VOC in the car. If you have any questions, please ask them. See you next time.
This article comes from car home, the author of the car manufacturer, and does not represent car home's position.