Natural radioactivity in some building materials and assessment of the associated radiation hazards

The results of the specific activities of ²³²Th, ²²⁶Ra and ⁴⁰K measured in samples of commonly used building materials in Bosnia and Herzegovina are presented. Measurements were performed by gamma-ray spectrometer with coaxial HPGe detector. The surface radon exhalation and mass exhalation rates for selected building materials were also measured. The determined values of specific activities were in range from 3.16 ± 0.81 Bq kg^-1 to 64.79 ± 6.16 Bq kg^-1 for ²³²Th, from 2.46 ± 0.95 Bq kg^-1 to 53.89 ± 3.67 Bq kg^-1 for ²²⁶Ra and from 28.44 ± 7.28 Bq kg^-1 to 557.30 ± 93.38 Bq kg^-1 for ⁴⁰K. The radium equivalent activity, the activity concentration index, the external and internal hazard indices as well as the absorbed dose rate in indoor air and the corresponding annual effective dose, due to gamma-ray emission from the radioactive nuclides in the building material, were evaluated in order to assess the radiation hazards for people. The measured specific activities of the natural radioactive nuclides in all investigated building materials were compared with the published results for building materials from other European countries. It can be noted that the results from this study are similar to the data for building materials from neighbouring countries and for building materials used in the EU Member States. The radiological hazard parameters of the building materials were all within the recommended limits for safety use.