There are fewer cars, the heating season has passed, but the smog has come again. Isn't burning coal the main cause of heavy air pollution?

Haze is a combination of fog and haze. Smog is very common in cities. In many areas of China, fog and haze are combined as disastrous weather phenomena for early warning and forecasting, which are collectively called "haze weather". Haze is the result of interaction between specific climatic conditions and human activities. The economic and social activities of high-density population will inevitably emit a large number of fine particles (PM 2.5). Once the emission exceeds the atmospheric circulation capacity and carrying capacity, the concentration of fine particles will continue to accumulate. At this time, if it is affected by calm weather, it is easy to have a wide range of smog.

In addition to heating and burning coal, there are other reasons for smog:

First: it's automobile exhaust. Large vehicles that use diesel are "recidivists" who emit PM 10, including buses, shuttle buses of various units and large transport trucks. Sources of toxic particulate matter in cities: firstly, automobile exhaust. Cars that use diesel are "habitual criminals" who emit particles. Small cars that use gasoline emit gaseous pollutants, such as nitrogen oxides, which are easily converted into secondary particulate pollutants in foggy days, aggravating smog.

Second: the waste gas emitted by industrial production. For example, metallurgy, kilns and boilers, electromechanical manufacturing, automobile repair and paint and building materials production produce a lot of waste gas from kiln combustion.

Third: Dust generated by construction sites and road traffic.

Fourth, particles can grow. The particle size of bacteria and viruses is equivalent to PM 0. 1 ~ PM 2.5. When the humidity and temperature in the air are appropriate, microorganisms will attach to particles, especially oil fume particles. After absorbing oil droplets, microorganisms will be transformed into more microorganisms, which will increase the number of biological toxic substances in smog.

5. Dust "smog" will also occur in home decoration. Indoor dust is pervasive, which is not only harmful to the health of staff and users, but also increases the cleaning burden. When the dust is serious, it also brings many hidden dangers to the decoration project.