Sarayköy Nuclear Research and Training Centre, Turkey
Meryem Seferinoğlu has completed her PhD at the age of 33 years from Hacettepe University, Institute of Pure and Applied Sciences, Department of Chemistry (Turkey). She worked as a postdoc at Luleå University of Technology, Division of Physics & Division of Process Metallurgy (Sweden) and worked as a researcher at European Commission-Joint Research Center-Institute fort reference Material and Measurements. She has been working Turkish Atomic Energy Authority, Sarayköy Nuclear Research and Training center, Radionuclide Metrology Department since 2007.
The measurement uncertainty is an essential part of the assessment of the measurement result. Previously the uncertainty in the radioactivity measurements was defined by the standard deviation of repeated measurements or was not reported. The standard deviation in a radioactive measurement given by the square root of the number of counts reflects only the statistical uncertainty of counting. Recently, more attention is given to the evaluation of the measurement uncertainty and to the preparation of uncertainty budget. There is, however, no common procedure for the estimation of a realistic uncertainty. The ISO Guide “Guide to the Expression of Uncertainty in Measurement” sets up general rules for evaluating and expressing uncertainty in a physical measurement. Some recent European documents give further details about calculating uncertainty in calibration and in quantitative chemical analysis. Nonetheless, the application of these concepts to environmental radioactivity measurements involving radiochemistry is not as straightforward as it should be, because the evaluation of uncertainty requires the analyst to take into account all stage of the method and all possible sources of uncertainty. The main purpose of this study is to demonstrate a procedure for evaluation of the measurement uncertainty in the analysis of plutonium isotopes in bilberry using a radiochemical separation method and alpha-particle spectrometry. The steps in the analytical procedure that contribute considerably to the combined measurement uncertainty are also identified. Identification of these steps might help lower the overall uncertainty of the measurements through decreasing the uncertainties in these steps.