Comparative study of precise measurements of natural radionuclides and radiation dose using in-situ and laboratory γ-ray spectroscopy techniques

Abstract

In this study, in-situ and laboratory γ-ray spectroscopy techniques were compared to evaluate the activity concentration of natural radionuclides in soil. The activity concentrations of U (Ra), Th, andK in the soil in 11 sites were simultaneously measured with in-situ portable HPGe and the NaI(Tl) detectors. In parallel, 55 soil samples collected from these sites were analyzed with a laboratory γ-ray spectroscopy technique (HPGe). A strong correlation was observed between the in-situ and laboratory HPGe techniques with a linear correlation coefficient (R) of 0.99 for Ra andTh and 0.975 for K, respectively. The in-situ HPGe technique shows a strong correlation with the NaI(Tl) detector. γ-Rays cps ofRa, Th, andK of the NaI (Tl) detector were then converted to specific activities (Bq kg unit) in soil using the empirical formulas obtained in this study. The absorbed dose rate in air at 1 m height above ground due to these radionuclides was calculated using the Beck's formula and the results were compared with measured values obtained with an high pressure ionization chamber. The results of the calculated and measured dose rate show a strong correlation of R = 0.96. The reliability and precision of analytical spectroscopy techniques of radioactivity and radiation dose were confirmed in this work.

Radiation Hazard evaluation and spatial dose rate mapping in mineralized region of Siwaliks: A case study from Una, Kangra and Hamirpur distt, Himachal Pradesh, India.

“…A weak correlation was observed between the activity concentrations of 226 Ra and 232 Th with a correlation coefficient of r 2 = 0.51. No correlation was observed between the measured radionuclides 232 Th and 40 K and 226 Ra and 232 Th (Fig 12) Authors have observed contrasting correlation among the radionuclides (Kovacs et al 2013;Baeza et al 2016, Hassan et al 2018 however in this case it indicates that these radionuclides 226 Ra , 232 Th and 40 K are of different geochemical origin.…”

Uranium migration and radioactive characteristics of the Sarıçiçek and Sarıhan Granodiorites

“…The ranges of the activity concentrations of 238 U, 232 Th, and 40 K were 6.055-72.86 Bq/kg, 19.48-95.81 Bq/kg, and 287.96-1633.86 Bq/kg for the in-situ measurements, and 6.71-70.89 Bq/kg, 16.08-83.62 Bq/kg, and 208.72-1262 Bq/kg in the laboratory, respectively. The determined radionuclide activity concentrations were compared with studies in the literature for similar rock types [63][64][65][66][67]. As a result, no significant difference was found between in-situ and laboratory measurements.…”

Development of a standard method for primary monitoring of exposure to environmental radiation

“…It is possible to find in scientific publications several studies on the evaluation of external (environmental) dose rates on different types of surfaces [17][18][19]. Several methods and detectors allow the quantification and detection of radiation [20].…”