Measurement of Natural Radioactivity, Radon Exhalation Rate and Radiation Hazard Assessment in Indian Cement Samples

AbstractBuilding materials are assumed to be the second source of Radon inside buildings. Due to low level of radon emanation from these materials, long term measurements are needed. Radiation doses from the building materials vary depending upon the natural radionuclides 226Ra, 232Th and their daughter products and 40K present in them. Cement is the main and important component used in the construction of buildings in many countries. These radio nuclides pose exposure risk due to their gamma ray emission and internally due to radon and its progeny that emit alpha particles. In the present study radon exhalation rate and the activity concentration of 226Ra, 232Th and 40K radionuclides in cement samples used in Aligarh region (U.P.), India have been measured by “Sealed Can technique” using LR-115 type II detectors and a low level NaI (Tl) based gamma ray spectrometer, respectively. From the measurements activity concentration of radionuclides 226Ra, 232Th and 40K vary from 9 to 28 Bq kg-1, 21 to 43 Bq kg-1 and 280 to 554 Bq kg-1 with overall average value of 19 Bq kg-1,35 Bq kg-1 and 406.7 Bq kg -1 respectively. Radon equivalent activity (Raeq) and external hazard index (Hex) have been found to vary from 60.8 to 121 Bq kg-1 and 0.16 to 0.30 respectively. The values are lower than the recommended safe values

Distribution of natural radionuclide along Main Central Thrust in Garhwal Himalaya

Study of natural radionuclide is important to assess the radiation level in a particular area. Radionuclide present in earth's crust is different for different geological areas because of the variety of soil and rocks present in a particular area. In present study, the estimation of natural radionuclides have been carried out along the Main Central Thrust (MCT) in Uttarkashi, Budhakedar, Ukhimath and Healang regions of Garhwal Himalaya, India. The large variations in the radionuclide distribution have been estimated along the Main Central Thrust. The 226Ra, 232Th and 40K contents in MCT area varies from 8 ± 1 Bq.kg−1 to 285 ± 28 Bq.kg−1 with an average of 64 Bq.kg−1, 7 ± 1 Bq.kg−1 to 136 ± 15 Bq.kg−1 with an average 69 Bq.kg−1 and 115 ± 18 Bq.kg−1 to 1588 ± 162 Bq.kg−1 with an average 792 Bq.kg−1, respectively. The radon exhalation rate and radon concentration in the soil of study area varies from 2.20 × 10−5 Bq.kg−1h−1 to 3.2 × 10−5 Bq.kg−1h−1 and 287 Bq/m3 to 417 Bq/m3, respectively. It was observed that the distribution of natural radionuclide in the soil of study area is not uniform and concentrated along geological active region. These values of radionuclide and radon mass exhalation rate may be used as baseline data for further study in the area. Keywords: Radionuclide, Radium, Thorium, Radon, Dos

Natural Radionuclide Analysis in Chattrapur Area of Southeastern Coastal Area of Odisha, India

The energy released in a spontaneous decay process of naturalradionuclides is the main source of the total radiation dose to humanbeings. Natural radionuclides are widely distributed in soil, rocks, air,and groundwater. In present investigation, the analysis of terrestrialradionuclides such as 226Ra, 232Th, and 40K in soil and sand of Chattarpurarea of southeastern coast of Odisha has been carried out using NaI(Tl)gamma ray detector. The higher activity concentrations of naturallyoccurring radionuclides have been reported from the study area. Thegamma radiationdose originating from the terrestrial radionuclides wasfound to vary from 95 to 1813 nGy/h with an average of 700 nGy/h. Thisstudy is important to generate a baseline data of radiation exposure in thearea. Health hazard effects due to natural radiation exposure arediscussed in details