Evaluation of radionuclide concentrations and associated radiological hazard indexes in building materials used in Egypt

Radionuclide concentrations of Ra-226, Th-232 and K-40 in different types of building materials used in Egypt were measured using gamma-ray spectroscopy. The results showed relatively moderate radionuclide concentrations for all samples except granite, which showed extremely high concentrations of 78.752.36, 2.820.11 and 2.370.07 kBq kg(1) for Ra-226, Th-232 and K-40, respectively. The radiological hazard indexes of radium equivalent activity (Ra-eq), external hazard index (H-ex) and internal hazard index (H-in), due to the presence of those radionuclides in the investigated building materials, were calculated. The released radon from the selected samples was measured using the AlphaGUARD radon monitor in order to use its value to calculate the radon emanation coefficient and the radon exhalation rate. The alpha equivalent dose (dose from indoor radon generated from building materials) was calculated using the measured values of the radium concentration and the radon emanation coefficient.