Key comparison BIPM.RI(I)-K1 of the air-kerma standards of the KRISS, Republic of Korea and the BIPM in ⁶⁰Co gamma radiation

Main text A new key comparison of the standards for air kerma of the Korea Research Institute of Standards and Science (KRISS), Republic of Korea, and the Bureau International des Poids et Mesures (BIPM) was carried out in the 60Co radiation beam of the BIPM in March 2022. The comparison result, based on the calibration coefficients for two transfer chambers and expressed as a ratio of the KRISS and the BIPM standards for air kerma, is 1.0006 with a combined standard uncertainty of 1.8 parts in 103. The result agrees within the uncertainties with the direct comparison carried out in 2010. The results are analysed and presented in terms of degrees of equivalence, suitable for entry in the BIPM key comparison database. 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).