A study on natural radiation exposure in different realistic living rooms

The second part of this paper deals with a study of natural radionuclide contents of samples collected from the building materials of the rooms under investigations in part one. Analyses were performed in Marinelli beakers with a gamma multichannel analyzer equipped with a NaI(Tl) detector. The samples revealed the presence of the uranium-radium and thorium radioisotopes as well as 40K. Nine γ-lines of the natural radioisotopes corresponding to 212Pb, 214Pb, 214Bi, 228Ac, 40K and 208Tl were detected and measured. The activity concentrations of 226Ra, 232Th and 40K were determined with mean activity concentrations of 58 ± 19, 31 ± 11 and 143 ± 62 Bq kg−1, respectively. These activities amount to a radium equivalent (Raeq) of 113 Bq kg−1 and to a mean value of external hazard index of 0.31.