CIPM Mutual Recognition Arrangement (CIPM MRA)García Gallegos, JaimeMitter, HelmutAbe, HisashiBenyon Puig, RobertCarroll, P.Choi, B. I.Deschermeier, ReginaEbert, V.Fernicola, VitoWang, L.Meyer, C.Smorgon, DenisVicente Mussons, Tomás2026-01-092026-01-092025-02-04Metrologia 62: 030010026-1394https://iopscience.iop.org/article/10.1088/0026-1394/62/1A/03001https://hdl.handle.net/20.500.12666/1612The final report has been peer-reviewed and approved for publication by the CCT, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA). 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 report summarises the results of the CCT-K8 key comparison in the field of humidity. The main target of this comparison was to obtain the degree of equivalence (DoE) between realizations of local scales of dew point temperature of humid gas (air), in the range from 30 °C to 95 °C, among the participating national metrology institutes. The report gives details of the scheme, procedure and analysis of the comparison. The overall results display a very good agreement of the nine participating laboratories. The results show excellent agreement between the realized scales with no detected outliers. The performance of the travelling standards was excellent and can be attributed to the intensive preconditioning and selection of the platinum resistance thermometers, prior to their integration into the measuring head assembly, that led to insignificant drift. In the conclusion, some lessons learned are reported that could be beneficial for future key comparisons.engAttribution-NonCommercial-ShareAlike 4.0 Internationalhttp://creativecommons.org/licenses/by-nc-sa/4.0/info:eu-repo/semantics/article10.1088/0026-1394/62/1A/03001info:eu-repo/semantics/openAccess