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In this paper, the natural radioactivity levels in a total of 117 samples of 14 different building materials collected from building construction sites and from the retailers in Adana were studied by means of gamma-ray spectrometer with HPGe detector. The mean activity concentrations of 226 Ra, 232 Th and 40 K measured in the studied building material samples ranged from 2.1 to 88.2 Bq kg À1 , 1.8 to 52.7 Bq kg À1 and 68.1 to 847.5 Bq kg À1 for 226 Ra, 232 Th and 40 K radionuclide, respectively. The external and internal index, the indoor absorbed dose rate and the corresponding annual effective dose were evaluated for potential exposure risks from the usage of the building material samples. The evaluated values of the external and internal index were below the recommended upper level. All the values of effective annual dose determined were lower than recommended exemption level of 0.3 mSv. The results suggest that the use of the studied building material samples in the construction of buildings is unlikely to give rise to any significant radiation exposure to the residents.

Variable dose (VD), T m-T stop , initial rise (IR), variable heating rate (VHR), peak shape (PS) and computerized glow curve deconvolution (CGCD) methods are used to determine the number of peaks, the order of kinetics (b), the activation energy (E a) and attempt-to-escape frequency (s) associated with the glow peaks in CaF 2 : Dy (TLD-200) after β-irradiation between the dose level 0.1 and 110 Gy. The T m-T stop procedure indicates that the glow curve of this crystal consists of at least nine glow peaks. The dose variation experiment indicates that seven of them, namely peaks 1-6 and 8, are of first-order kinetics and peaks 7 and 9 are of general-order kinetics. However, the T m-T stop procedure and the CGCD method have indicated that peak 6 has general-order kinetics too. The activation energy found with the IR, VHR, PS and CGCD methods for peak 4 yield very close values. For all other peaks, there is no agreement between the results of all the applied methods. This work also indicates that the post-irradiation annealing and the heating rate have pronounced effects on the evaluated kinetic parameters of all glow peaks.

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