An Assessment of Naturally Occurring Radioactive Materials (NORM) in Environmental Samples of Kailashtila and Salda Nadi Gas Fields of Bangladesh

An assessment of activity concentrations in the naturally occurring radioactive materials have been carried through gamma ray spectroscopy method for the environmental samples from two gas fields of Bangladesh. Besides, the radiological hazard parameters are also estimated. The observed activity concentrations of
²²⁶
Ra were varied from 0.90 Bq/kg to 67.73 Bq/kg whose average value was found to be 14.46 Bq/kg. The concentrations of
²³²
Th were varied from MDL to 58.56 Bq/kg whose average value was found to be 17.62 Bq/kg. The activity concentrations of
⁴⁰
K were varied from 179 Bq/kg to 647 Bq/kg whose average value was found to be 327 Bq/kg. A comparison of the average values of samples of two fields was made. Moreover, the radiological hazards parameters were estimated for each sample and compared them with world average value as well as safety limits. The findings of radium equivalent activity and external hazard index for all samples are lower than the safety or permissible limit. In addition, the findings of absorbed dose rate and annual effective dose of most of the samples are lower than world average value except sludge sample in Kailashtila. In this research, it is revealed that, most of the samples of these fields contain lower activity concentrations and so, these areas are not threatening to workers, people and the atmosphere.