The Working Group for Electricity and Magnetism of the Inter-American Metrology System (SIM) initiated the key and supplemental regional comparisons SIM.EM-K1-K2-S6 to provide the first internationally recognized comparisons of precision resistance measurements for nations of the western hemisphere. These comparisons include the official metrology institutes of six members of SIM and follow the guidelines for key comparisons under the 1999 CIPM Mutual Recognition Arrangement (MRA). The National Institute of Standards and Technology (NIST) provided the comparison standards and acted as the pilot laboratory in the SIM.EM-K1-K2-S6 comparisons, which began in January 2006 and were completed in September 2007.

By means of procedures for linking key comparison data, the SIM.EM-K1-K2 comparisons will help to provide assurance of equality in measurements between the nations organized in SIM and the participants in the CCEM key comparisons. The analysis included in this report (Appendix A) specifically provides methods for calculating the degrees of equivalence and their uncertainties between the national measurement standards of the participating laboratories (Appendix B). A subsequent analysis (Appendix G) provides methods and results linking this regional comparison to CCEM key comparison CCEM-K2 and a recent BIPM–NIST bilateral comparison at the 1 Ω level.

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 CCEM, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).