Radiation exposure or the population living in the area of NPP 'Kozloduj' by gas-aerosol radionuclide releases in the ground layer of the atmosphere for the period 1996 - 1997

The assessment of radiation exposure of the population living in the area of NPP 'Kozloduy' was carried out for a period of 2 years on the basis of a mathematical model method of distribution of radioactive substances in the air. The method is based on a Gaussian model for division of radioactive substances, and meteorological, demographic, soil and other characteristics of the area of the NPP. The factors forming the individual doses of radiation exposure are: external radiation exposure by radioactive gases and aerosols contained in the air; external radiation exposure by radioactive substances precipitated on the ground; internal radiation exposure by radionuclides penetrating the body by inhalation. The collective doses of radiation exposure have been calculated for separate zones and in total for the population from the area. The values of the annual individual effective doses for the population around NPP are between 109 Sv and 107 Sv. This is below 0,1 % from the background radiation. Assessment of radiation exposure of the population was done in comparison with the maximum allowable annual dose, set by the Basic Standards of Radiation Protection - 1992 and in comparison with the background radiation to which the Bulgarian population is exposed