ABSTRACT
During the period from May, 1986 to November, 1987 the aerosol samples were collected around the Chernobyl nuclear power plant to define radioactive aerosol particle sizes by filter pack technique. The parameters of lognormal distribution (activity median aerodynamic diameter, AMAD, and geometric standard deviation) were defined for various radionuclides in aerosol form. The submicron aerosol particle were only shown to be produced by the damaged block-4 during the initial period after the accident. AMAD was increased up to 4–6 μm at the following stages when the secondary updraft of aerosol particles from contaminated surfaces became the dominant source of radioactive aerosols.
