Ongoing Key Comparison Research Articles

Final report, ongoing key comparison BIPM.QM-K1, ozone at ambient level, comparison with NMC-A*STAR, July 2022

Main textAs part of the ongoing key comparison BIPM.QM-K1, a comparison has been performed between the ozone national standard of Singapore maintained by the National Metrology Centre, A*STAR (NMC, A*STAR) and the common reference standard of the key comparison, maintained by the Bureau International des Poids et Mesures (BIPM), via a transfer standard maintained by the National Institute of Standards and Technology (NIST). The instruments have been compared over a nominal ozone amount-of-substance fraction range of 0 nmol/mol to 500 nmol/mol.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 CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

The CCL-K11 ongoing key comparison. Final report for 2023

Main textSix lasers from six national metrological institutes (NMIs) were compared in the year 2023 as part of the CCL-K11 ongoing key comparison, initiated by the 13th meeting of the Comité Consultative des Longueurs (CCL) in 2007. The absolute frequency of theses lasers was measured in three different node laboratories following the technical protocol for CCL-K11. All are practical realisations of the definition of the metre according to the MeP for the definition of the metre.Five standards are He-Ne-lasers stabilized on the f component of the R(127) 11-5 transitions of molecular iodine 127I2 with a wavelength of approximately 633 nm.The sixth standard is a fibre laser stabilized to the P(16) (ν1+ν3) transition of molecular acetylene 13C2H2 with a wavelength of approximately 1542 nm. The technical protocol was deliberately designed to accommodate artefacts of different wavelengths in a common framework.The results of these measurements are compiled in the present report. The comparison reports, as communicated by each participant, are included in the main document.This document constitutes the thirteenth final report for the ongoing key comparison CCL-K11.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 CCL, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

Final report, ongoing key comparison BIPM.QM-K1, ozone at ambient level, comparison with NIM, Oct 2023

Main textAs part of the ongoing key comparison BIPM.QM-K1, a comparison has been performed between the ozone national standard of China maintained by the National Institute of Metrology (NIM) and the common reference standard of the key comparison, maintained by the Bureau International des Poids et Mesures (BIPM). The instruments have been compared over a nominal ozone amount fraction range of 0 nmol mol−1 to 500 nmol mol−1.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 CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

Final report, ongoing key comparison BIPM.QM-K1, ozone at ambient level, comparison with FMI, March 2023

Main textAs part of the ongoing key comparison BIPM.QM-K1, a comparison has been performed between the ozone national standard of Finland, maintained by the Finnish Meteorological Institute (FMI) and the common reference standard of the key comparison, maintained by the Bureau International des Poids et Mesures (BIPM). The instruments have been compared over a nominal ozone amount fraction range of 0 nmol mol-1 to 500 nmol mol-1.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 CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

Final report, ongoing key comparison BIPM.QM-K1, ozone at ambient level, comparison with EMPA, June 2023

Main textAs part of the ongoing key comparison BIPM.QM-K1, a comparison has been performed between the ozone standard of the World Meteorological Organization maintained by the Swiss Federal Laboratories for Materials Science and Technology (EMPA) and the common reference standard of the key comparison, maintained by the Bureau International des Poids et Mesures (BIPM). The instruments have been compared over a nominal ozone amount fraction range of 0 nmol mol−1 to 500 nmol mol−1.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 CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

The CCL-K11 ongoing key comparison. Final report for 2022

Main textTwo lasers from two national metrological institutes (NMIs) were compared in the year 2022 as part of the CCL-K11 ongoing key comparison, initiated by the 13th meeting of the Comité Consultative des Longuers (CCL) in 2007. The absolute frequency of R(127) 11-5 (≈633 nm) transitions of molecular iodine was measured for these lasers following the technical protocol for CCL-K11. The results of these measurements are compiled in the present report. The comparison reports, as communicated by each participant, are included in the main document.This document constitutes the twelfth final report for the ongoing key comparison CCL-K11.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 CCL, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

Final report, ongoing key comparison BIPM.QM-K1, ozone at ambient level, comparison with NPL, June 2022

Main textAs part of the ongoing key comparison BIPM.QM-K1, a comparison has been performed between the ozone national standard of United Kingdom maintained by the National Physical Laboratory (NPL) and the common reference standard of the key comparison, maintained by the Bureau International des Poids et Mesures (BIPM). The instruments have been compared over a nominal ozone amount fraction range of 0 nmol mol−1 to 500 nmol mol−1.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 CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

Final report, ongoing key comparison BIPM.QM-K1, ozone at ambient level, comparison with CMS/ITRI, March 2024

Main textAs part of the ongoing key comparison BIPM.QM-K1, a comparison has been performed between the ozone standard of Chinese Taipei maintained by the Industrial Technology Research Institute/Center for Measurement Standards (CMS/ITRI) and the common reference standard of the key comparison, maintained by the Bureau International des Poids et Mesures (BIPM). The instruments have been compared over a nominal ozone amount fraction range of 0 nmol mol−1 to 500 nmol mol−1.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 CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

Final report, ongoing key comparison BIPM.QM-K1, ozone at ambient level, comparison with VSL, April 2024

Main textAs part of the ongoing key comparison BIPM.QM-K1, a comparison has been performed between the ozone standard of the Netherlands maintained by the Van Swinden Laboratorium (VSL) and the common reference standard of the key comparison, maintained by the Bureau International des Poids et Mesures (BIPM). The instruments have been compared over a nominal ozone amount fraction range of 0 nmol mol−1 to 500 nmol mol−1.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 CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

Final report, ongoing key comparison BIPM.QM-K1, ozone at ambient level, comparison with DHMZ, July 2022

Main textAs part of the ongoing key comparison BIPM.QM-K1, a comparison has been performed between the ozone national standard of Croatia maintained by the Croatian Meteorological and Hydrological Service (DHMZ) and the common reference standard of the key comparison, maintained by the Bureau International des Poids et Mesures (BIPM). The instruments have been compared over a nominal ozone amount fraction range of 0 nmol mol-1 to 500 nmol mol-1.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 CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

Final report, ongoing key comparison BIPM.QM-K1, ozone at ambient level, comparison with NIST, July 2022

Main textAs part of the ongoing key comparison BIPM.QM-K1, a comparison has been performed between the ozone national standard of the United States maintained by the National Institute for Standards and Technology (NIST) and the common reference standard of the key comparison, maintained by the Bureau International des Poids et Mesures (BIPM). The instruments have been compared over a nominal ozone amount fraction range of 0 nmol mol−1 to 500 nmol mol−1.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 CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

Final report, on-going key comparison BIPM.QM-K1, ozone at ambient level, comparison with NIMT, September 2022

Main textAs part of the ongoing key comparison BIPM.QM-K1, a comparison has been performed between the ozone national standard of Thailand maintained by the National Institute of Metrology (Thailand) (NIMT) and the common reference standard of the key comparison, maintained by the Bureau International des Poids et Mesures (BIPM). The instruments have been compared over a nominal ozone amount fraction range of 0 nmol mol−1 to 500 nmol mol−1.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 CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

Final report, ongoing key comparison BIPM.QM-K1, ozone at ambient level, comparison with LNE, March 2023

Main textAs part of the ongoing key comparison BIPM.QM-K1, a comparison has been performed between the ozone national standard of France maintained by the Laboratoire National de métrologie et d'Essais (LNE) and the common reference standard of the key comparison, maintained by the Bureau International des Poids et Mesures (BIPM). The instruments have been compared over a nominal ozone amount fraction range of 0 nmol mol−1 to 500 nmol mol−1.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 CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

Final report, ongoing key comparison BIPM.QM-K1, ozone at ambient level, comparison with ISCIII, May 2023

Main textAs part of the ongoing key comparison BIPM.QM-K1, a comparison has been performed between the ozone national standard of the Instituto de Salud Carlos III (ISCIII) and the common reference standard of the key comparison, maintained by the Bureau International des Poids et Mesures (BIPM). The instruments have been compared over a nominal ozone amount-of-substance fraction range of 0 nmol mol−1 to 500 nmol mol−1.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 CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

Final report of CCQM-P225a and b, international comparison on carbon dioxide in air and nitrogen at ambient levels (350 μmol/mol to 800 μmol/mol)

Main textThe pilot studies CCQM-P225a and b aimed at validating the performance of the pVT−CO2 manometric reference facility maintained at the BIPM as a reference for the planned ongoing comparisons BIPM.QM-K2a and b for CO2 in air and nitrogen standards, respectively, over the range 350 μmol mol−1 to 800 μmol mol−1. The planned launch date of the BIPM.QM-K2a and b comparisons is 2024 and will enable NMIs and DIs to have access to on-demand comparisons for their CO2 in air and nitrogen standards over the range 350 μmol mol−1 to 800 μmol mol−1.The pilot studies supplemented the validation activities on the BIPM reference facility already reported in CCQM-P188, and ongoing validation studies against NIST, NOAA and VSL gas standards. A description of the BIPM facility performance will be submitted for publication in a peer-reviewed journal in 2023, with a full uncertainty analysis showing that it can operate with a standard uncertainty of 0.1 μmol mol−1 over the amount fraction range of the comparison (Viallon et al 2023b).The comparison was organised using a sufficient number of independent standards, to demonstrate the performance of the BIPM system, whilst limiting the duration of the pilot study, allowing the key comparison to start as planned in 2024. Following discussions at the 44th GAWG meeting it was decided that comparisons with 3 independent standards at 3 nominal amount fraction values (380, 480 and 800 μmol mol−1) in the two matrices (air and nitrogen) would be sufficient.Results presented in this report show a good agreement between values assigned by participants and those measured at the BIPM, over the entire range of the comparison and for both matrices (air and nitrogen). The BIPM pVT−CO2 facility is ready to act as reference facility for the ongoing key comparison BIPM.QM−K2.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 CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

Final report, ongoing key comparison BIPM.QM-K1, ozone at ambient level, comparison with DMDM, September 2022

Main textAs part of the ongoing key comparison BIPM.QM-K1, a comparison has been performed between the ozone national standard of Serbia maintained by the Directorate of Measures and Precious Metals (DMDM) and the common reference standard of the key comparison, maintained by the Bureau International des Poids et Mesures (BIPM). The instruments have been compared over a nominal ozone amount fraction range of 0 nmol mol-1 to 500 nmol mol-1.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 CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

Final report, ongoing key comparison BIPM.QM-K1, ozone at ambient level, comparison with CHMI, September 2021

Main textAs part of the ongoing key comparison BIPM.QM-K1, a comparison has been performed between the ozone national standard of Czechia maintained by the Czech Hydrometeorological Institute (CHMI) and the common reference standard of the key comparison, maintained by the Bureau International des Poids et Mesures (BIPM). The instruments have been compared over a nominal ozone amount fraction range of 0 nmol/mol to 500 nmol/mol.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 CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

Final report, ongoing key comparison BIPM.QM-K1, ozone at ambient level, comparison with INRIM, February 2022

Main textAs part of the ongoing key comparison BIPM.QM-K1, a comparison has been performed between the ozone national standard of Italy maintained by the Istituto Nazionale di Ricerca Metrologica (INRIM) and the common reference standard of the key comparison, maintained by the Bureau International des Poids et Mesures (BIPM). The instruments have been compared over a nominal ozone amount fraction range of 0 nmol/mol to 500 nmol/mol.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 CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

The CCL-K11 ongoing key comparison. Final report for 2021

Main textFour lasers from three national metrological institutes (NMIs) were compared in the year 2021 as part of the CCL-K11 ongoing key comparison, initiated by the 13th meeting of the Comité Consultative des Longuers (CCL) in 2007. The absolute frequency of R(127) 11-5 (≈633 nm) and of R(56) 32-0 (≈532 nm) transitions of molecular iodine was measured for these lasers following the technical protocol for CCL-K11. The results of these measurements are compiled in the present report. The comparison reports, as communicated by each participant, are included in the main document.For the very first time in this key-comparison a standard working on a different operating principle is reported. CMI participated with a frequency doubled Nd:YAG laser stabilized to an iodine transition (Designation: CMI-YAG1). The technical protocol was deliberately designed to accommodate artefacts of different wavelengths in a common framework. Moreover, CMI participated with a second laser standard also. The institute has different CMC entries for the two laser types. Both entries refer to the same service category of highest metrological level, but are technically well separated. Due to the layout of CCL-K11 the KCRV is immune to a multiple participation of a single NMI. It was thus considered to include both measurements in this report.This document constitutes the 11th final report for the ongoing key comparison CCL-K11.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 CCL, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

The CCL-K11 on-going key comparison. Final report for the period 2018 to 2020

Main textTo 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 CCL, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).