Radioactive analysis of cement and its products collected from Shaanxi, China

This note presents a study of Ra-226, Th-232, and K-40 in cement and its products manufactured in some areas of Shaanxi, China. The concentrations of Ra-226, Th-132, and K-40 were 46.2, 28.4, and 137.4 Bq kg(-1), respectively, for cement brick; and 64.7, 48.7, and 161.3 Bq kg(-1), respectively, for cement plaster. The concentration of 226Ra, Th-232, and 4 K in cement ranges from 34.7 to 68.3 Bq kg(-1) with a mean value of 56.5 Bq kg(-1),18.5 to 51.7 Bq kg(-1) with a mean value of 36.5 Bq kg(-1), and 126.8 to 224.6 Bq kg(-1) with a mean value of 173.2 Bq kg(-1), respectively. The measured activity concentrations for these radionuclides were compared with the reported data of other countries. The radium equivalent activities (Ra-eq), external hazard index (Hex) and internal hazard index (Hi) associated with the radionuclides were calculated. The Raeq values of cement and cement products are lower than the limit of 370 Bq kg(-1), equivalent to a gamma dose of 1.5 mSv y(-1). The values of Hex and Hi are less than unity.