Investigation of natural radioactivity in building materials commonly used in Sudan

Investigation of radioactivity content of commonly used building materials in Khartoum State is carried out during the year 2010. A total of 25 samples of natural and manufactured materials from different types of building materials have been collected and measured using gamma spectrometry system. The activity concentrations have been determined for radium (2''2''6''Ra), thorium (''2'3''2Th) and potassium (''4''0K) in each sample. The concentrations of radium (represents activity of uranium and its decay series) have been found to rang from 2.8 Bq/kg in (gravel) to 108.2 Bq/kg (porcelain), thorium between 48 and 302 Bq/kg and the potassium concentration varies between 82.3 Bq/kg in (gravel) to 1413.3 Bq/kg in (marble). The activity index has also been calculated and found that it is less than 1 (mean value of 0.77 range between 0.33 and 1.97), and less than 6 for surface materials. The results have been compared with European previous studies. It is concluded that the measured radioactivity of building materials are within acceptable levels and dose not poses any risk from radiation protection point of view. (Author)