In the aftermath of devastating tsunami, studies were undertaken to assess its impact on the environmental radioactivity profile in the beach sands along the entire east coastal region of Tamil Nadu state (~1000 km) and compared with previously established pretsunami distribution profile. The results of the present study clearly indicate that the radioactivity content of ²³²Th and ²³⁸U in the beach sands registered a steep fall (52% and 41%, respectively), whereas the ⁴⁰K activity has increased by 26%. This is attributed to the hydrodynamics of tsunami waves, which removed huge quantities of beach minerals that have been built-up over a few decades. The individual activity content of the three primordial radionuclides, total activity content, comparison between pre- and post-tsunami data for all the 32 sites, and their statistical analyses are covered in the paper.

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Black powder solids are formed inside the sales gas pipelines as a result of internal corrosion due to condensed moisture and the presence of corrosive gases, namely, H₂S, CO₂, and O₂. Naturally occurring radioactive material, principally the radionuclides lead-210 and polonium-210, and naturally occurring mercury (NOM) (Hg) have been identified in black powder. A detailed investigation into both the radiological components and the presence of NOM associated with black powder was carried out by Saudi Aramco. The aim of the investigation was to determine if waste produced during pipeline scraping operations presented a workers protection or environmental control problem due to the radioactivity and mercury present. The investigation looked at Saudi Aramco's entire sales gas pipeline network and spanned scraping operations over a 3-year period. This article details the sampling and analysis methods used to assess black powder samples, the results of sample analysis and advice provided to ensure workers' protection, and environmental control of the waste produced during pipeline scraping activities.

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In this study, a comparison is made between the selection of the most proper and accurate methods for ²³⁵U activity determination according to the available conditions with the smallest error possible. The detection of ²³⁵U activity is used to determine the mass of the ²³⁵U in the samples and consecutively, the uranium enrichment which is important for the nuclear safeguards' needs and the monitoring of the radionuclides in the environment. Various methods have been studied to distinguish between counting rate contributions from both²³⁵U and ²²⁶Ra to the 186 keV energy region in samples of uranium in natural form.

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Use of diagnostic reference levels (DRLs) is an important tool for patient dose optimization in interventional radiology. DRLs are normally expressed in terms of kerma-area product (P_ka). However, no direct method is available to estimate the probability of skin reactions using system displayed quantities. The aim of this work was to measure skin entrance doses (SEDs) in patients undergoing coronary angiography (CA) and percutaneous coronary interventions (PCI) using Gafchromic films and establish DRLs. The details of patients, exposure parameters, and dose quantities were recorded for 572 patients. Out of these, skin doses were measured for selected 64 patients using Gafchromic film. Measured SEDs are in the range of 48.2–740 mGy and 84–1242 mGy for CA and PCI, respectively. The data of 572 patients were analyzed, and 75^th percentile of P_kawas calculated. DRLs for CA and PCI in terms of P_kaare found to be 34 and 134 Gy.cm², respectively. DRLs for CA and PCI in terms of cumulative air kerma (K_a) at reference point are found to be 590 mGy and 1930 mGy, respectively. SED has a good correlation with K_a, however, it does not correlate well with P_ka.

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In this study, 16 water samples collected from homes and the water tanks in various districts from two different natural water sources, supplying Adıyaman's domestic drinking water. Measurements of radon gas activity concentrations in collected samples have been performed by AlphaGUARD PQ2000 PRO radon detector. The average radon (²²²Rn) activity concentrations of samples taken from the natural water resources and homes were found to be 0.39 ± 0.11 and 0.51 ± 0.14 Bq/L, respectively. In addition, the annual effective dose equivalent that exposed due to radon gas in drinking water is also calculated and found to be 1.30 ± 0.36 μSv/y. The upper limit for radon gas activity concentrations in drinking waters has been defined by the United States Environmental Protection Agency (USEPA), United Nations Scientific Committee on the Effects of Atomic Radiation, and World Health Organization to be 11, 40, and 100 Bq/L, respectively. The measured values of radon gas activity concentrations are lower than that of limit value defined by the USEPA.

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In India, a single type of dosimeter is used all over the country for estimation of occupational doses due to X, beta, and gamma radiations. The quality assurance program of external personnel monitoring in India includes an annual announced test and periodic blind tests. The announced test carried out by a central agency includes various energies and angles of irradiation. Blind tests are carried out by specified users of personnel monitoring service who are distributed throughout the country. Due to the lack of easy availability of various energy sources, blind tests are mostly carried out for a single energy. Analysis of the results is carried out by means of ANSI criteria or trumpet curve analysis which may not be sufficiently stringent given that a single energy and angle are used. In view of this and also to meet the specific requirements of the Indian monitoring scenario, keeping in mind existing practices, an attempt is made to have a new look at the analysis of blind test results. The criteria which have been considered are zeroing of dosimeters, coefficient of variation, and bias. The results of a blind test based on harmonized procedures can be utilized to understand the actual quality of service and also identify deviations in procedures, if any.

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A new class of clay bricks designed, developed, and tested for their radiation shielding efficiency. The bricks were prepared using natural clay, lake clay, and lightweight clay and loaded with different concentrations of Pb (NO₃)₂. The gamma-ray shielding parameters were measured for these bricks with a transmission type of good geometry setup and operated at 511 and 662 keV energies. The gamma-ray spectrometer consists of a 2“×2” NaI (Tl) detector, 8K multichannel analyzer. The ²²Na and ¹³⁷Cs point isotropic gamma-ray sources were used in this study. To evaluate the efficiency of these bricks, various shielding parameters, such as linear attenuation coefficient, mass attenuation coefficient, mean-free path, half-value layer and tenth-value layer were calculated. The X-COM software was used to calculate these parameters theoretically, and both the experimental and theoretical values were compared, and they are in good agreement. These results suggest that the clay bricks prepared with the natural and lake clay attenuate more radiation than the lightweight clay bricks. It is also observed that the lightweight bricks prepared with the solutions with higher loadings of lead nitrate showing increased attenuation, this may be attributed to the reason that at higher loadings of LN, the porous gaps of lightweight bricks are being filled by the LN particles and contributed to the attenuation of radiation.

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Preliminary results of ambient indoor and outdoor gamma dose rates estimated in 20 distinct areas of Amritsar city, Punjab, are exhibited by utilizing Dosimeter-Radiometer MKS-03 (SARAD). This study was planned in such a way to get a uniform and representative distribution of estimations. The indoor to outdoor dose rate ratio was ascertained which showed that the indoor gamma dose rate as contrasted with outdoor gamma dose rate has elevated levels of exposure due to confined space and poor ventilation. The indoor and outdoor annual effective dose rate was likewise estimated from the exposure point of view, and it varied from 0.35 to 1.61 mSv/y and from 0.11 to 0.44 mSv/y. The average values of outdoor and indoor effective dose rate levels in all of these locations were well below the world average value prescribed by the United Nations Scientific Committee on Effects of Atomic Radiations.

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Introduction: Tantalite and other solid mineral deposits in Oke-Ogun occupy a very large landscape, and the possibilities of further exploration in new landscape and abandoning unproductive sites cannot be ruled out. These landscapes when abandoned become hideout for criminals and ritualistic activities which pose a great threat to the wellness of the people in the area and Nigerians at large. Objectives: This study attempts to investigate the radiological safety of these abandoned mines so as to convert them to economical valuable sites that can serve as a means of employment for population of the unemployed youth in the area and Nigeria at large. Materials and Methods: A total of seventeen soil samples were randomly selected. These samples were processed and analyzed for activity concentrations of ²²⁶Ra, ²³²Th, and ⁴⁰K using Hyper Pure Germanium Gamma Spectrometer. RESidual RADioactivity software version (6.5), a computer program developed by the Environmental Assessment Division of Argonne National Laboratory, was used for dose prediction for 70 years using the activity concentrations of soil samples from all the selected sites as its input parameter for the software. Predicted doses were estimated with respect to the three exposure pathways, namely external gamma irradiation from radionuclides in the soil samples, inhalation of dust particles, and inadvertent ingestion of soil. Results: The measured activity concentrations of radionuclides: ²²⁶Ra for all the sites is in the range of (17–177) Bq/kg, ²³²Th in the range of (2–107) Bq/kg, and ⁴⁰K in the range of (650–1667) Bq/kg. The predicted dose for all the sites is within the range of 0.05–0.35 mSv/y with Eluku mining site having values greater than the permissible limit of 0.25 mSv/y. The health implication of these values is that three of the sites (Gbedu, Sepenteri, and Komu) are safe for other usages. Conclusion: Any of these three mining sites may be used for re-creational purposes, fishing and building of estates to mention but a few.

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