title: Assessment of natural radioactivity levels of cements and cement composites in the Slovak Republic.
abstract: The radionuclide activities of 226Ra, 232Th and 40K and radiological parameters (radium equivalent activity, gamma and alpha indices, the absorbed gamma dose rate and external and internal hazard indices) of cements and cement composites commonly used in the Slovak Republic have been studied in this paper. The cement samples of 8 types of cements from Slovak cement plants and five types of composites made from cement type CEM I were analyzed in the experiment. The radionuclide activities in the cements ranged from 8.58-19.1 Bq·kg(-1), 9.78-26.3 Bq·kg(-1) and 156.5-489.4 Bq·kg(-1) for 226Ra, 232Th and 40K, respectively. The radiological parameters in cement samples were calculated as follows: mean radium equivalent activity Ra(eq) = 67.87 Bq·kg(-1), gamma index Iγ = 0.256, alpha index Iα = 0.067, the absorbed gamma dose rate D = 60.76 nGy·h(-1), external hazard index H(ex) = 0.182 and internal hazard index H(in) was 0.218. The radionuclide activity in composites ranged from 6.84-10.8 Bq·kg(-1) for 226Ra, 13.1-20.5 Bq·kg(-1) for 232Th and 250.4-494.4 Bq·kg(-1) for 40K. The calculated radiological parameters of cements were lower than calculated radiological parameters of cement composites.
authors.affiliation: Faculty of Civil Engineering, Institute of Environmental Engineering, Technical University of Košice, Vysokoškolská 4, Košice 042 00, Slovakia. adriana.estokova@tuke.sk.
authors.forename: Adriana
authors.initials: A
authors.lastname: Eštoková
authors.forename: Lenka
authors.initials: L
authors.lastname: Palaščáková
mesh_terms: D000512:Alpha Particles; D003252:Construction Materials / Q000032:analysis*; D004784:Environmental Monitoring; D005720:Gamma Rays; D006801:Humans; D011188:Potassium / Q000032:analysis; D011197:Potassium Radioisotopes / Q000032:analysis; D011834:Radiation Monitoring; D011868:Radioisotopes / Q000032:analysis*; D011883:Radium / Q000032:analysis; D018570:Risk Assessment; D012588:Scintillation Counting; D018154:Slovakia; D013910:Thorium / Q000032:analysis
chemical_list: D011197:Potassium Radioisotopes; D011868:Radioisotopes; D013910:Thorium; D011188:Potassium; D011883:Radium