Due to the legislation and general concern of radiation levels in dwellings in India, there is a need to continuously monitor the indoor concentrations of radon and Thoron in different geographical areas of Bangalore, which could be of great significance to exposure to occupants, particularly in living places. This paper presents the 222Rn and 220Rn concentrations measured in houses in 10 different locations in Bangalore. The data was continuously obtained for a period of 2 years since 2007, covering more than 150 dwellings. The arithmetic mean values of 222Rn and 220Rn were found to be 35.0 and 21.5 Bq · m-3. The effective dose rate received by the population in the study area ranged between 0.1—0.5 mSv · y-1, the arithmetic mean concentration was 0.2 ± 0.03 mSv · y-1. The result shows no significant radiological risk for the inhabitants.
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