LAUSR

Gamma-ray dose rates have been measured in the indoor and outdoor air of Hassan City. The measurements were done from 25 locations of Hassan City at 1 m above the ground surface for radiometric, geophysical and environmental surveys using a lightweight portable radiation survey meter (scintillometer). The meter reading fluctuates around a mean value and is proportional to the count rate detected by the unit. This is because of the random nature of radioactivity. In the present study, the absorbed gamma dose rates in indoor and outdoor air varies from 69 ± 2 to 481 ± 18 nGy h-1 with a geometric mean of 180 ± 6 nGy h-1 and 20 ± 0 to 371 ± 14 nGy h-1 with a geometric mean of 107 ± 3 nGy h-1. The annual effective gamma dose rates in indoor and outdoor air varies from 0.34 to 2.36 mSv y-1 with a geometric mean of 0.88 mSv y-1 and 0.02 to 0.45 mSv y-1 with a geometric mean of 0.12 mSv y-1. The gamma dose rates of Hassan City is higher compared to the world average value and lower when compared to other locations of India.