Comparison between indoor and outdoor measurements of Rn-220 decay product concentrations and meteorological parameters

摘要

Data from continuous measurements of the potential alpha energy of thoron progeny (Rn-220) in several dwellings within the same village, located in the south of Germany, show that there is a typical seasonal dependency of the Rn-220 concentration.rnAdditional measurements of Rn-220 outdoor concentrations in the vicinity of these houses allows testing for a correlation between indoor and outdoor concentrations. Decay product concentrations of Rn-222 at all locations are also evaluated for the comparison of exposure by thoron and radon progenies.rnFor collecting these data a computer controlled filter device with a silicon a-detector and a flow meter controlling the air flux was used. The peak areas of Po-214, Po-218 and Po-212 can be calculated by special procedures from the a-spectra to get the equilibrium equivalent concentration for thoron and radon decay products.rnA meteorological station at a distance of not more than 500 m of each outdoor and indoor measuring location was installed to collect data of temperature, air pressure, humidity, wind velocity and wind direction. The comparison of these parameters with the thoron and radon concentrations shows the influence of the weather conditions on the radon and thoron exposure in the dwellings and outdoors.