Natural radionuclides contents and radon exhalation rates in building materials used in South Korea

The natural radionuclide (Ra-226, Th-232 and K-40) contents of building materials commonly used in South Korea have been determined by a gamma ray spectroscopy system using a high purity germanium detector. The radon exhalation rates and emanation coefficients of building materials have also been studied. The average concentrations of Ra-226, Th-232 and K-40 in building materials were in the range of 6.47-271 Bq.kg(-1), N.D.-89.9 Bq.kg(-1) and 16.8-1081 Bq.kg(-1), respectively. The average radon exhalation rates and emanation coefficients were in the range of 0.0061-0.2404 Bq.kg(-1).h(-1) and 2.39-11.5%, respectively.