Key comparison BIPM.RI(I)-K1 of the air-kerma standards of the IST-LPSR, Portugal and the BIPM in 60Co gamma radiation

Abstract

A comparison of the standards for air kerma of the Instituto Superior Técnico, Laboratório de Proteção e Segurança Radiológica (IST-LPSR), Portugal and of the Bureau International des Poids et Mesures (BIPM) was carried out in the 60Co radiation beam of the BIPM in December 2015. The comparison result, evaluated as a ratio of the IST-LPSR and the BIPM standards for air kerma, is 1.0026 with a combined standard uncertainty of 1.7 × 10−3. The results for an indirect comparison made at the same time are consistent with the direct results at the level of 1.1 parts in 103. The results are analysed and presented in terms of degrees of equivalence, suitable for entry in the BIPM key comparison database.Main textTo 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 the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).