Comparison of intercomparison results of gamma ray spectrometry of spiked and real samples.

The quality and comparability of results of different comparison schemes depend strongly on how the samples were prepared and how the reference values were determined. To test the influence of different approaches to preparing comparison samples and determination of reference values on the final evaluation of participants' results, analyses of S-shapes for Cs-134 and Cs-137 in different comparison schemes in time period 1986-2016 were performed. This study pointed out significant improvement in the quality of performance of comparison tests of selected providers.