a natural or artificial aerosol with a radioactive dispersed phase.
Natural radioactive aerosols form as a result of the decay of radon isotopes emitted from the soil surface into the atmosphere, as well as during the interaction of particles of cosmic radiation with the nuclei of atoms of elements that are components of the air. The radioactive atoms thus formed precipitate onto particles of nonradioactive atmospheric dust. In addition, dust containing radioactive isotopes of potassium, uranium, and thorium is carried from the soil surface into the atmosphere by winds. A certain quantity of radioactive aerosols enters the atmosphere with cosmic dust and meteorites.
Artificial radioactive aerosols containing fission products and radioactive isotopes with induced radioactivity are formed within a certain radius from the explosion of a nuclear bomb, as well as in industrial or accidental radioactive emissions at atomic industry plants, in uranium mines, and in enrichment plants.
The composition of radioactive aerosols depends on their origin and on atmospheric conditions.