Speaker
Description
A new soil reference material (RM) to improve the quality assurance and quality control of the gamma radioactivity measurement in environmental samples was developed by the Korea Research Institute of Standards and Science (KRISS). Depending on the user's request, the type and specific radioactivity of radionuclides to be included in the soil RM can be selected. In this study, the homogenized raw materials were put in the drum container and the standard solution containing the 137Cs and 60Co radionuclides was slowly sprayed into the drum container. Ten samples were randomly selected for among-bottle homogeneity and two samples were taken from each bottle for within-bottle homogeneity. The homogeneity test for the soil RM fulfilled the requirement of the ISO Guide 35. The self-absorption correction factor and the coincidence summing correction factor were calculated by the Monte Carlo N-Particle (MCNP) code and the efficiency transfer (EFFTRAN) code, respectively. In conclusion, the reference values of 137Cs and 60Co in the soil RM were determined to be 118.7 and 124.4 Bq/kg, respectively. And the expanded uncertainties of the radionuclides were around 8.0%.
