An overview of results obtained in intercomparison exercises for determination of actinides

•The goal of this study is an overview of results obtained in intercomparison exercises for determination of actinides.•The disagreement of results for Np-237 was evaluated.•Improvements in separation procedures were done.

In recent years the Jožef Stefan Institute participated in numerous intercomparison exercises for determination of natural and man-made radionuclides. The reported values were mostly in good agreement with the resulting reference values. This paper describes an analysis of the measurement results obtained in intercomparison exercises for determination of actinides in the period from 2009 to 2011, organised by the National Physical Laboratory and the Bundesamt für Strahlenschutz. The review covers neptunium, plutonium and americium radioisotopes over this period.