Measurement of natural radioactivity in rock samples using gamma ray spectrometry

Abstract

Natural radioactivity due to 226Ra, 232Th and 40K in the rock samples collected from Dhanbad city of Jharkhand, India was measured using gamma-ray spectrometry. The concentrations of 226Ra, 232Th and 40K in the studied rock samples range from below the detection limit to 3.08 Bq/kg, 5.35-37.39 Bq/kg and 168.8-416.9 Bq/kg, respectively. The concentrations of these radionuclides are compared with the recommended values. To evaluate the radiological impact of the natural radioactivity, the radium equivalent activity, the annual effective dose rate, the values of both external and internal indices and the gamma index were estimated and compared with the internationally acceptable values.