Performance, Measurements and Potential Radiological Risks of Natural Radioactivity in Cements Used in Jordan

This study examined the cement properties and potential radiological risks of natural radioactivity in cements used in Jordan. The results showed that all cement types were compliant with the Jordanian and European standard specifications (JSS. 30-1/2007) and (EN. 19-1/2000), respectively. The maximum value of compressive strength was found in white Portland cement. Ambient temperature for all samples occurred between 330 min and 500 min and was released with approximately the same rate values. The activity concentration of Ra-226, Th-232, and K-40 were detected in all cement samples. The maximum value of activity concentrations (in Bq/kg +/- SD) of Ra-226 was 79.52 +/- 4.67, while it was for Th-232 and K-40 30.99 +/- 2.85 and 354.70 +/- 19.64, respectively. The highest value of the dose rate was 117 +/- 8 nGy/ h. The annual effective dose due to absorption and radium equivalent crest values were 574 +/- 8 mu Sv/h and 343 +/- 16 Bq/kg, respectively. The external hazard, activity concentration index and alpha index were less than unity for all samples. All measurements and calculations were within the recommended international standard values (ISVs), except for S3 & S5 samples. The results were compared with those of other studies from different countries all over the world.