Evaluation of natural radioactivity for building materials samples used in Tall Al Ubaid Archaeologist in Dhi-Qar governorate - Iraq
Keywords:Gamma ray spectrometry, natural radioactivity, Building materials, NaI (Tl) Detector.
In this study, the levels of natural radionuclide concentrations were measured for radium ), thorium and potassium ) in the building materials used in Tall Al Ubaid Archaeologist site of Dhi-Qar Governorate-Iraq. Using one of gamma-ray spectroscopy techniques, which consists of a scintillation detector sodium iodide activated by thallium NaI (Tl) with dimensions of (3"×3"), measurements performed at the laboratory of environmental and radiation pollution research in the department of Physics, College of Science, University of Dhi-Qar. The obtained results for radionuclides in all of building materials samples were analyzed and tabulated against the global average and the allowed limits as recommended by international scientific agencies. The average value of specific radiative activity concentrations values of natural radioactive elements ( and ) and the equivalent activity of Radium ) ( for samples of building materials are (15.17- 21.47, 11.04-20.92 and 192.75-291.45) Bq⁄Kg and (49.60-71.78) Bq.⁄Kg, respectively. The absorbed dose rate (nGy/h), annual effective dose (mSv/y), estimated gamma coefficient (Bq/Kg) were calculated. All values in the four studied areas were lower of the allowable limits, all values of the risk index (internal and external) in units (Bq/Kg) in the studied archaeological sites are less than one. All the results indicate that all concentrations of radioactive elements targeted in the study were within the allowable limits despite the differences in the concentration values of these elements according to the samples.