Since 1979, nine national metrology institutes (NMIs) and an international laboratory have submitted 16 samples of known activity of ¹⁹²Ir to the International Reference System (SIR) for activity comparison at the Bureau International des Poids et Mesures (BIPM), with comparison identifier BIPM.RI(II)-K1.Ir-192. The activities ranged from about 0.4 MBq to 4.2 MBq. The degrees of equivalence, between each equivalent activity measured in the SIR and the key comparison reference value (KCRV), have been calculated and the results are given in the form of a matrix for three laboratories. A graphical presentation is also given. The results of a CCRI(II) comparison held in 2002 for this radionuclide, with comparison identifier CCRI(II)-K2.Ir-192 are linked to the BIPM comparison through individual measurements of the comparison ampoules in the SIR. This has enabled six NMIs and one international laboratory to update their earlier SIR results, and another eight NMIs and the BIPM to have degrees of equivalence in the key comparison database (KCDB). Consequently, the enlarged matrix and graphical presentation are for 19 laboratories in total.

Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/.

The final report has been peer-reviewed and approved for publication by Section II of the Consultative Committee for Ionizing Radiation (CCRI(II)), according to the provisions of the Mutual Recognition Arrangement (MRA).