Nuclear Seminar - Alžbeta Brandýsová (31.3.2021)
Wednesday 31.3.2021 at 14:00, online
Mgr. Alžbeta Brandýsová:
Study of the relationship between the content of radionuclides in the soil and possibility of using radon potential maps for identification of radon-prone areas
Abstract:
Natural radioactivity is mainly characterized by a small number of primordial radionuclides, among which the most relevant ones are 40K and the members of 238U and 232Th decay chains. Based on their concentrations in the soil, it is possible to calculate the gamma dose rate at 1 m above the ground, and also to estimate the exhalation rate of 222Rn from the soil. In order to study the relationships between terrestrial radionuclides 40K, 232Th, 226Ra and 222Rn, the Mochovce area (~ 24x22 km2) was chosen because radionuclide content in this locality has been well documented due to the presence of a nuclear power plant. The main interest of several scientific studies in the field of determining the radon potential of the soil follows from the existence of a possible health risk due to exposure from radon and its decay products on human body. The high content of radon in the soil is also the precursor of its increased indoor radon levels. Inhabited areas, in which a high level of indoor radon concentration is achieved due to natural (geogenic) reasons are called ,,radon-prone areas”. These areas can be identified via direct measurements of radon concentration or through indirect methods which use parameters of the soil (222Rn and 226Ra concentration, porosity, soil gas permeability, etc.) The map of radon potential after its rescaling served as a basis for the identification of high-risk localities, where measurements of indoor radon in the houses of some villages were performed and evaluated. In 53% of cases, the reference level (300 Bq/m3) of indoor radon concentration measured in winter season was exceeded. The results of the measurements show, that after appropriate rescaling the radon potential map can be an effective tool for identification of areas with high indoor radon concentration.