Key comparison BIPM.RI(I)-K5 of the air-kerma standards of the CIEMAT, Spain and the BIPM in 137Cs gamma radiation

Abstract

Main textA first comparison of the standards for air kerma of the Laboratorio de Metrología de Radiaciones Ionizantes - Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (LMRI-CIEMAT), Spain, and of the Bureau International des Poids et Mesures (BIPM) was carried out in the 137Cs radiation beam using the radiation protection facility of the International Atomic Energy Agency (IAEA) in Seibersdorf, Austria, in September 2023. The comparison was done using the CIEMAT and the BIPM primary standards and a transfer instrument belonging to the CIEMAT. The direct comparison result, evaluated as a ratio of the CIEMAT and the BIPM standards for air kerma, is 0.9992 with a combined standard uncertainty of 2.2 parts in 103. The result for the indirect comparison is in agreement with the direct result at the level of 2.2 parts in 103. The results are analysed and presented in terms of degrees of equivalence, suitable for entry in the BIPM key comparison database, to update the 2014 APMP comparison result.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 https://www.bipm.org/kcdb/.The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).