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Aerosols are called suspensions of solid or liquid particles in a gas. There are many classifications of aerosol particles. The researchers select one or another classification depending on the goals
specific research and accents, placed in it.
In the physics of aerosols, the classification of particles by size is considered to be the most rational. Thus, aerosols with dimensions <0.1 μm are called finely dispersed. Further, in increasing order, medium-dispersed - from 0.1 to 1 μm and coarsely dispersed -> 1 μm follow. Such a
the gradation of particles can be used to study and describe the behavioral characteristics of aerosols in strict dependence on their morphometric characteristics, or when it is very important to emphasize
specific particle size and its specific properties, such as the ability to penetrate the respiratory tract.
There is also a well-known classification of Young particles,
proposed by him in 1953. Aerosol particles ranging in size from 10* -9 to 10* -7 belong to the Aitken nuclei (Aitken mode). The main process for the formation of these particles was the nucleation of nuclei or primary photochemical reactions. In the same group he attributed and viruses. The next largest particles (from 10* -7 to 10* -6) are called large and the main way of their formation is coagulation. This group includes particles of sea salt, as well as the smallest of dust particles.
Aerosols with sizes from 10* -5 are called giant and are formed by dispersing the substance. This includes biogenic and dust particles. This classification is very popular, because the most
The most frequently studied group of particles is in the Aitken mode.
In ecosystem studies, the genetic classification of aerosols is used, according to which aerosols should be subdivided into natural and anthropogenic, primary and secondary.
Natural aerosols are all particles formed due to natural processes of dispersing a substance, namely:
- mineral dust (products of weathering of the soil cover,
volcanic particles);
- marine aerosol (drops of sea solution, sea salt particles);
- biogenic particles (direct removal, chemically transformed);
- organic aerosol (for example, smoke from burning biomass);
- products of natural transition of particles from the gas phase to the solid (produced directly from the gas phase).

Traditionally, anthropogenic aerosols include those particles that arise in the process of human economic activity. For example, when extracting minerals by the open method, agricultural activities, the operation of TPPs, the impact of automotive
exhaust fumes, natural fires, explosions.
Separation of marine and terrigenous aerosols is used by many authors, and their basic difference is not only the composition, but also the methods of formation and the form of particles in the atmosphere.