Sources and classification of atmospheric pollution.

In previous issues of the “Human, Society & Nature ”, we met with a group of the main air pollutants - greenhouse gases, oxides of nitrogen, sulfur, carbon and solid particles. In this issue we will get acquainted with the sources and classification of atmospheric pollution.

Based on the nature of the phenomenon, the following types of air pollution are distinguished: chemical, physical and biological.

          - In the first case, an increased concentration of hydrocarbons, heavy metals, sulfur dioxide, ammonia, aldehydes, nitrogen oxides and carbon is observed in the atmosphere.

          - During biological pollution in the air there are vital products of various organisms, toxins, viruses, spores of fungi and bacteria.

         - A large amount of dust or radionuclides in the atmosphere indicates physical effects. The effects of thermal, noise and electromagnetic emissions are attributed to the same species.

         The composition of the air is affected by both man and nature. Natural sources of air pollution: volcanoes during the period of activity, forest fires, soil erosion, dust storms, decomposition of living organisms. A tiny fraction of the influence also falls on cosmic dust resulting from the combustion of meteorites.

Anthropogenic sources of air pollution:

 - enterprises of the chemical, fuel, metallurgical, engineering industries;

 - agricultural activities (spraying pesticides with the help of aviation, animal waste);

- heat power plants, heating of premises with coal and firewood;

- transport (the most "dirty" types - airplanes and cars).


How to determine the degree of air pollution?


When monitoring the quality of atmospheric air in a city, not only the concentration of substances harmful to human health is taken into account, but also the time period of their exposure. Atmospheric pollution is assessed by the following criteria:

  • Standard Index (SI) - an indicator obtained by dividing the largest measured single concentration of polluting material by the maximum permissible concentration of impurities.
  • The Atmospheric Pollution Index (API) is a complex value, which, when calculated, takes into account the hazard coefficient of the polluting substance, as well as its concentration - the average annual and maximum permissible daily average.
  • Maximum Repeatability (MR) - expressed as a percentage of the frequency of exceeding the maximum permissible concentration (maximum one-time) for a month or a year.

The level of air pollution is considered low when SI is less than 1, API varies between 0–4, and MR does not exceed 10%. With an increased level of atmospheric emissions, SI is 1–5, API- 5–6, MR - 10–20%. The cities with indicators are distinguished by a high degree of air pollution: SI - 5–10, API- 7–13, MR - 20–50%.

How to make air cleaner?

The introduction of technologies that regulate the volume of emissions allows reducing atmospheric pollution at industrial enterprises.

In the fight for clean air, an important strategy element is a comprehensive waste management program. It should be aimed at reducing the amount of garbage, as well as its sorting, recycling or reuse. Urban planning aimed at improving the environment, including the air, involves improving the energy efficiency of buildings, building a bicycle infrastructure, and developing high-speed city transport.