Soil gas radon, indoor radon and gamma dose rate in CZ: contribution to geostatistical methods for European atlas of natural radiations.

A comparison of Czech indoor radon data, soil gas radon data and gamma dose rate was performed on the data sets of 92,276 indoor radon measurements in existing dwellings (National Radiation Protection Institute - NRPI), database of 9500 test sites of soil gas radon measurements (Czech Geological Survey - CGS) georeferenced to levels of gamma dose rate map. Three methods were used for the study of soil gas Rn-indoor Rn relationship: (1) based on the vectorised point soil gas and indoor data related to vectorised areas of gammadose rate, (2) vectorised soil gas-indoor data based on vectorised geological units and (3) soil gas and indoor data related to grid squares 10 x 10 km2. The first and second methods seem to express the closer correlation compared with the third one, however the correlation using the third method is influenced by the representativeness of data value in the square of 100 km2 area. On the other hand, the third method can be used for the overview coverage of the continental areas with lack of input information.