Natural Radioactivity, Radon Exhalation Rates and Radiation Doses in the Soil Samples Collected from the Vicinity of Kolaghat Thermal Power Plant, West Bengal, India

Natural radioactivity has been determined by means of a highly efficient thallium-doped sodium iodide detector in soil sample from surface vicinage “Kolaghat Thermal Power Plant” The activity concentration (specific activity) is found to vary 23.70 ± 3.41 33.90 4.33 Bqkg-1 for 226Ra, 6.67 2.01 21.60 2.11 232Th and that 40K 461.01 66.16 610.25 80.87 with expected value 29.26 3.50, 4.86 2.03 517.53 71.61 Radium-226, Thorium-232 Potassium-40 correspondingly. radon exhalation rates were also computed all samples using the "Sealed Can Technique”. due fluctuates 47.9 6.2 157.6 11.3 Bqm-3 having an arithmetic mean 89.3 7.9 Bqm-3. rate mass estimated fluctuate from17.3 2.2 56.8 4.1 mBqm-2h-1 expectation 32.1 3.0 0.6 0.1 2.1 0.2 mBqkg-1h-1 averaged out 1.2 mBqkg-1h-1respectively. Radiation doses calculated these samples. Indoor outdoor annual effective doses, Absorbed dose rates, External Hazard index inhalation exposure, known as dose, was varied 0.19 0.25 mSv y-1, 39.30 51.61 nGyh-1, 0.048 0.063 mSvy-1, 0.21 0.28 0.29 0.36 2.04 6.70 μSvy-1 respectively. values which obtained this study are be well below allowed permissible limits, so may used building construction material.