Radon-~(222) concentrations and the environmental radiation dose rates at Misasa spa districts, Japan

摘要

We have been carrying out continuously the measurements of Rn-~(222) concentrations in air with a set of indoors and outdoors using the convenient and highly sensitive Pico-rad detectors with active carbon adsorber for several years at Misasa spa districts. Rn-~(222) concentrations in air on geologically formed granite layers were higher than those basaltic layers. And the mean y radiation dose rates at Misasa spa districts measured by means of optically stimulated luminescence (OSL) dosemeters for 3 months, they showed the similar tendency to those of Rn-~(222) on geological map.