THE RADIOACTIVITY OF BRICKS PRODUCED IN SERBIA

Natural radioactivity of the brick, one of the most used building materials was investigated. The content of natural radionuclides in the samples was measured by HPGe gamma-spectrometry. The average values of specific activities of 226Ra, 232Th and 40K in the samples are: 31 ± 9, 40 ± 11 and 460 ± 118 in Bq kg-1 , respectively. The absorbed dose in the air was computed by the method of buildup factors for the standard model of the room. The obtained values for the absorbed dose are in the range of 9 – 47 (nGy h-1 ), with the average of 36 ± 9 nGy h-1 . The radiation hazard was estimated calculating the corresponding gamma index and the effective dose. The gamma index belongs to the range of 0.11 to 0.56, and the effective dose is in the range of 0.044 – 0.23 (mSv), far below the reference limit of 1 mSv.