ASSESSMENT OF RADIATION HAZARDS FOR SOIL SAMPLES FROM VICINITY OF AL-BAYDA CITY, YEMEN

In this work the radioactivity concentrations of the natural radioactive nuclides 226Ra, 232Th and 40K were calculated in the surface soil samples from Al-Bayda governorate, middle of Yemen. Gamma spectroscopy is used to analyze the samples and the concentrations of radioisotopes were determined using hyper-pure germanium (HPGE) detector in Bq kg-1 dry-weight. The measured average activity concentrations of 226Ra, 232Th and 40K were 27.657±1.7, 35.071±2.1 and 544.713±16.8 Bqkg-1, respectively. Different hazard indices were also determined. The results showed that the average radium equivalent activity (Raeq), the absorbed dose rate (Dr), absorbed dose rate in indoor air, annual effective dose, the external hazard index (Hex), internal hazard index (Hin) and representation level index (Iγ) were: 119.75 Bqkg-1, 56.42 nGyh-1, 78.986 nGy h-1 , 46 µSv, 0.32, 0.40 and 45, respectively. The mean value of (Raeq) obtained in this study was in good agreement with that of the international value while the mean values of the other indices were found to be higher than the international reference values. The data were discussed and compared with those given in the literature.