A study of the mechanism of formation of radon daughter aerosols

Abstract

The formation of radon daughter aerosols in air is found to be markedly influenced by the presence of charges and vapours. Experiments have been carried out with natural radon in the air to show that radon daughter products behave as single ions of high mobility in filtered dry air whereas they are attached to cluster aerosols formed in the presence of certain charges and vapours. In these experiments the cluster aerosols have been formed with ethanol vapour in the presence of small negative ions. Knowledge of this mechanism of attachment of radon daughters to cluster aerosols has also been used for the estimation of airborne radon. The radioactivity of these aerosols is studied by filtration through membrane filters. The degree of equilibrium between radon and its daughters in atmospheric air has been studied on the basis of this mechanism. The mechanism is of fundamental importance in understanding the nature of radon daughter products in the air under different environmental conditions. DOI: 10.1111/j.2153-3490.1966.tb00284.x