Study of ambient gamma exposure rate in Mandya, South India

The gamma exposure rates were measured at the height of 1m from the ground level in Hill stations, houses, Schools, Hostels, Bus stand, diagnostic centers, Railway station, Temples and Churches in and around Mandya, using a portable GM tube based Environmental radiation dosimeter. Outdoor measurements were also made in an open air next to each indoor site. The range and mean values of indoor gamma absorbed dose rates for different places are found to be 83.5 to 349.7 nGy/h and 149.8 ± 59.2 nGy/h respectively. The outdoor absorbed dose rate ranges between 74.8 to 309.7 nGy/h with a mean value of 131.2 ± 49.9 nGy/h. The highest indoor absorbed dose rate of 349.7 nGy/h is found at Adichunchanagiri new temple. The highest outdoor dose rate of 309.7 nGy/h is found outside the temple in M K Koppal. Higher dose rates are found in hill stations compared to other places. The results are systematically analyzed, discussed and reported. (author)