RAGHAD SABBAR HADI, HUSAIN HAMAD AL-GAZALY AND ALI ABID ABOJASSIM*
Department of Physics, Faculty of Science, University of Kufa, Iraq
*(e-mail : ali.alhameedawi@uokufa.edu.iq)
(Received : June 22, 2019; Accepted : August 18, 2019)
ABSTRACT
In the present study, natural radioactivity (238U, 232Th and 40K) was measured in soils of selected schools of Al-Mishkab district at Al-Najaf Governorate. These measurements were carried out by the use of NaI (TI) detector, that has the dimensions of (3″× 3″). The results showed that the average specific activity for 238U was found to lie in the range of 0.79±0.10 to 9.30±0.34 Bq/kg with an average value of 5.44±0.27 Bq/kg. The values for 232Th was found to lie in the range of 0.77±0.06 to 8.43±0.10 Bq/kg with an average value of 3.68±0.16 Bq/kg and the value for 40K was found to lie in the range of 73.51±1.0 to 246.28±1.83 Bq/kg with an average of 159.89±1.415 Bq/kg. The resulted average radioactivity was compared with the average values reported by UNSCEAR 2008 for 238U, 232Th and 40K which were 33, 45 and 420 Bq/kg, respectively, so they were within the permissible limits. The average value of radium equivalent activity, absorbed dose rate in air, external hazard index, internal hazard index, the annual effective dose (indoor and outdoor) and excess life mite cancer risk were calculated. It was concluded that all the results of natural radioactivity and radiological hazard in the present study were within the permissible limits.
Key words : Natural radioactivity, adiological hazard, gamma-ray, radiation in school, Al-Mishkab district