An Investigation of Radiological Risk in Test Dwelling through Experimental and Simulation Approaches

Study of radon, thoron and their progeny are important from radiological point of view. This work is towards their prediction, measurement, decay behavior, estimation of associated factors and effective dose for different room conditions (open and closed). The levels are measured experimentally using active monitors, dosimeters and deposition-based progeny sensors. Radon is found uniformly distributed for the open room condition while thoron shows complex behavior. A decrease in radon concentration is found through prediction and measurement for open room condition with increase of homogeneity. The solid radon progenies got distributed uniformly in the closed room. Total equilibrium equivalent concentration (EEC) for thoron is found comparatively more for the open room condition, EEC (unattached) found more for the closed environment, while for radon both are higher for closed room condition. The gas levels along with distribution are found to be affected by the vent ambiance. The average of unattached factors is estimated to be f_Rn (0.1) for open, (0.2) for closed while f_T (0.1) for open, (0.3) for closed room. Comparison of measurement and simulation approach shows reasonable matching of the results and validation of the simulation code. Different doses and conversion factors are also estimated and found within the recommended limits.