Final report on international comparison APMP.QM-S4: Carbon dioxide in nitrogen at 2000 µmol/mol

This report presents the results of APMP.QM-S4, a supplementary comparison. This comparison is designed to test the capabilities of the NMIs to measure and certify carbon dioxide at a nominal amount fraction of 2000 µmol/mol in nitrogen. The previous key comparisons regarding carbon dioxide, CCQM-K1.b and CCQM-K52, had been done at a lower range than that in this comparison. This comparison gives an opportunity to the NMIs to submit supporting evidence for CMC at a higher range. 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 CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).