Glavic-Cindro D, Korun M
Jozef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia.
Appl Radiat Isot. 2004 Feb-Apr;60(2-4):217-20. doi: 10.1016/j.apradiso.2003.11.020.
Due to biased potassium activity results in the proficiency test soil samples, measurements of a set of control samples containing potassium compounds with known concentrations of potassium were performed in order to establish the traceability of potassium activity results in to the unit of mass. The radius and the mass of the control samples were equal to the radius and the mass of the proficiency test samples. The density of samples in both cases varied between 1 and 2g/cm(3). No influence of sample density on the potassium activity results could be detected at the accuracy level achieved. The source of disagreement could not be found within the participating laboratory.
