The first key comparison on carbon dioxide in nitrogen dates from 1993–1994 (CCQM-K1.b). Since then, numerous national metrology institutes (NMIs) have been setting up facilities for gas analysis, and have developed claims for their Calibration and Measurement Capabilities (CMCs) for these type mixtures. In the April 2005 meeting of the CCQM Gas Analysis Working Group, a policy was proposed to repeat key comparisons for stable mixtures every 10 years. Consequently in 2007 the key comparison CCQM-K52 'Carbon dioxide in synthetic air' was carried out. This comparison is consistent with the proposed policy and enables NMIs that could not participate in the previous comparison to take part. This report describes the results of a key comparison for carbon dioxide in synthetic air. The amount-of-substance fraction level of carbon dioxide chosen for this key comparison (360 µmol/mol) represents the ambient level of this component in air. In total 18 NMIs and one WMO laboratory participated in the comparison. The agreement of the results in this key comparison is very good. With a few exceptions, the results agree within 0.3% (or better) with the key comparison reference value. Most of the participants that did not participate in CCQM-K1.b do very well. In some cases, the uncertainties claimed are quite large in comparison with the NMIs for which this comparison is a true 'repeat', but the observed differences with the KCRV usually reflect that these claims are realistic. All participants in CCQM-K1.b that participated in this key comparison show improved results.
International Comparison CCQM-K52 carbon dioxide in synthetic air / Wessel, R. M.; VAN DER VEEN, A. M. H.; Ziel, P. R.; Steele, P; Langenfelds, R; VAN DER SCHOOT, M; Smeulders, D; Besley, L; DA CUNHA, V. S.; Zhou, Z; Qiao, H; Heine, H. J.; Martin, B; Macé, T; Gupta, P. K.; AMICO DI MEANE, E; Sega, Michela; Rolle, F; Maruyama, M; Kato, K; Matsumoto, N; Kim, J. S.; Moon, D. M.; Lee, J. B.; Murillo, F. R.; Nambo, C. R.; AVILA SALAS, M. D. J.; Castorena, A. P.; Konopelko, L. A.; Kustikov, Y. A.; Kolobova, A. V.; Pankratov, V. V.; Efremova, O. V.; Musil, S; Chromek, F; Valkova, M; Milton, M. J. T.; Vargha, G; Guenther, F. R.; Miller, W. R.; Botha, A; Tshilongo, J; Mokgoro, I. S.; Leshabane, N.. - In: METROLOGIA. - ISSN 0026-1394. - 45:(2008), pp. 08011-08011. [10.1088/0026-1394/45/1A/08011]
International Comparison CCQM-K52 carbon dioxide in synthetic air
SEGA, MICHELA;ROLLE F;
2008
Abstract
The first key comparison on carbon dioxide in nitrogen dates from 1993–1994 (CCQM-K1.b). Since then, numerous national metrology institutes (NMIs) have been setting up facilities for gas analysis, and have developed claims for their Calibration and Measurement Capabilities (CMCs) for these type mixtures. In the April 2005 meeting of the CCQM Gas Analysis Working Group, a policy was proposed to repeat key comparisons for stable mixtures every 10 years. Consequently in 2007 the key comparison CCQM-K52 'Carbon dioxide in synthetic air' was carried out. This comparison is consistent with the proposed policy and enables NMIs that could not participate in the previous comparison to take part. This report describes the results of a key comparison for carbon dioxide in synthetic air. The amount-of-substance fraction level of carbon dioxide chosen for this key comparison (360 µmol/mol) represents the ambient level of this component in air. In total 18 NMIs and one WMO laboratory participated in the comparison. The agreement of the results in this key comparison is very good. With a few exceptions, the results agree within 0.3% (or better) with the key comparison reference value. Most of the participants that did not participate in CCQM-K1.b do very well. In some cases, the uncertainties claimed are quite large in comparison with the NMIs for which this comparison is a true 'repeat', but the observed differences with the KCRV usually reflect that these claims are realistic. All participants in CCQM-K1.b that participated in this key comparison show improved results.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
