Assessment of Radionuclide Concentration and Exhalation Rates in some NORMs and TENORMs of Shivalik Region

Abstract

226Ra, 232Th, their decay products 222Rn, 220Rn and 40K significantly contribute to the mean dose from natural background radiation. This study reports the concentration of radionuclides in Naturally Occurring Radioactive Materials (NORMS) and Technologically Enhanced Naturally Occurring Radioactive Materials (TENORMS) of the Shivalik region of Punjab and Himachal Pradesh. The activity of radionuclides 226Ra, 232Th and 40K in different NORMS (soil, sand, rocks) and TENORMS (tiles, marble, cement) were calculated by Gamma spectrometry method using an HPGe detector. Radon mass exhalation and thoron surface exhalation rates were also determined using a Smart RnDuo monitor for the above samples. From the results, it could be concluded that the radon mass exhalation rate and radium activity were obtained to be maximum for tile no. 2 and minimum for white marble samples. Similarly, the thoron surface exhalation rate and thorium activity occurred maximum in tile no. 2 and minimum for safedi. The radium equivalent activity (Raea), gamma activity concentration index (I), internal hazard index (Hint) and external hazard index (Hext) were computed using appropriate relations. The values range between 5.858 to 188.944, 0.0403 to 1.377, 0.028 to 0.615 and 0.015 to 0.510 having mean values of 107.256, 0.685, 0.325, and 0.256, respectively.