title: Gamma activity and radiation dose in concrete building blocks used for construction of dwellings in Jos, Nigeria.
abstract: Radioactivity concentrations of concrete building block samples made and used in Jos, Nigeria, were determined using a gamma ray spectrometry method. The mean values of the radioactivity concentrations were calculated as 66, 126 and 589 Bq kg(-1) for (226)Ra, (232)Th and (40)K, respectively. The radium equivalent activities ranged between 131 and 712 Bq kg(-1), with six of the samples exceeding the UNSCEAR reported maximum permissible level of 370 Bq kg(-1). The mean radium equivalent activity (292 Bq kg(-1)) is higher than the values available in the literature for some countries by factors ranging between 2 and 5, a situation that can be traced to the practice of sourcing sand aggregates from mining sites. The indoor annual effective dose for a dwelling of dimension 3.6 x 3.6 x 3.0 m(3) was calculated as 0.81 mSv.
authors.affiliation: Department of Physics, University of Ibadan, Ibadan, Nigeria. jaaademola@yahoo.com
authors.forename: J A
authors.initials: JA
authors.lastname: Ademola
authors.forename: I P
authors.initials: IP
authors.lastname: Farai
mesh_terms: D001822:Body Burden; D003252:Construction Materials / Q000032:analysis*; D005720:Gamma Rays; D006798:Housing; D006801:Humans; D009549:Nigeria; D011829:Radiation Dosage; D011835:Radiation Protection / Q000379:methods*; D011868:Radioisotopes / Q000032:analysis*; D011874:Radiometry / Q000379:methods*; D012062:Relative Biological Effectiveness
chemical_list: D011868:Radioisotopes