Abstract
Percentage and radionuclides content in the brick material used in construction depend on the origin and the geological condition of the source material. Bricks used as building materials in Egypt were manufactured from clay and rocks extracted from deposited sediments of Nile River. The aim of the study was to determine the radiation activity resulting from a different kind of bricks used in the construction process in Egypt. In the present work, 20 samples of three types of bricks, clay brick (CB), making facade brick (MFB) and firebrick (FB) were selected from different regions and plants in Egypt. The activity concentration of Ra-226, Th-232 and K-40 in many brick under investigation were measured using gamma ray spectroscopy system. Results showed that, the radium equivalent concentration (Raeq) calculated and compared well with the world reported values. As shown in the results, the mean values of radioactivity concentrations of Ra-226, Th-232 and K-40 for CB bricks, which represent the highest ??? in many bricks in the present study with values (39, 38 and 199 Bq/kg), respectively. Radium equivalent activities calculated for many bricks in the study???. The average values of radium equivalent activities 110, 88 and 83 Bq/kg, for bricks type were found to be below the global level of 370 Bq/kg of building materials. The maximum values of Ra-eq calculated for all studied samples were found to be 152.79 Bq/kg for (CB4) sample, 112.0 for (MFB10) sample, and 118.77 Bq/kg for (FB20) sample. To test the radiological hazard of the natural radioactivity, the potential radiological hazards were assessed by calculating the indoor absorbed gamma dose rate (DR), the annual effective dose rate, outdoor and indoor (Deff), the alpha index (I alpha), the gamma index (I gamma), and the external hazard (Hex) and internal hazard (Hin) indices. Considering that the values of the risk indicators were lower than the recommended levels, we have concluded that the buildings constructed from these brick samples in our study are safe for the population.