[Factors determining the formation of radon levels inside buildings].

The theoretical and experimental investigation of radon levels inside dwellings of Tomsk was carried out. The statistical analysis of gathered results let us to reveal the significant factors, which define the formation of radon levels inside the buildings and dependencies of radon distribution. The significant factors are: building type (urban or rural), year season, floor level (is significant only for buildings of rural type), daytime and social factor includes habits and life stile of inhabitants. The distribution of mean radon levels in buildings obeys the log-normal law. The distribution of radon level among the floors for urban type of buildings obeys the normal law, for rural type of buildings--exponential law.