Final report of COOMET.T-K7: Regional key comparison of water triple point cells (COOMET theme No 395/BY/07)

Abstract

Key comparison COOMET.T-K7 is a regional key comparison of water triple point cells. Seven national metrology institutes—VNIIM (Russian Federation), BelGIM (the Republic of Belarus), NSC IM (Ukraine), INSM (the Republic of Moldova), KazInMetr (the Republic of Kazakhstan), GEOSTM (Georgia) and INIMET (the Republic of Cuba)—participated in this regional COOMET comparison and BelGIM was appointed as the pilot laboratory and the coordinator.The transfer standards were water triple point cells.The comparison was performed in three stages: (1) each participating laboratory carried out comparisons of the transfer cell with its national standard cell in local conditions; (2) the transfer cells were forwarded together with measurement results to BelGIM, where they were compared with the standard BelGIM cell using its laboratory equipment; and (3) the transfer cells were sent back to laboratories, where they were compared again to the national standard cells in order to determine the stability of the transfer cells.The degrees of equivalence of the national standards that took part in the regional COOMET comparison were determined relative to the reference value of the CCT key comparison CCT-K7 through the measurement results of the linking national metrology institute VNIIIM, which took part in both comparisons.The report provides the results of this comparison and detailed information about the method of estimation of the degrees of equivalence of the standards of the participating laboratories and their uncertainties.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 the CCT, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).