The key comparison CCQM-K76 was designed to test the capabilities of the participants to measure and certify sulfur dioxide in nitrogen, and to provide supporting evidence for the CMCs of these institutes for sulfur dioxide. Also, as sulfur dioxide is designated a core compound, and the 100 µmol/mol concentration is within the designated core compound concentration range, this comparison was also designed to demonstrate core capabilities of institutes which qualify under the rules of the Gas Analysis Working Group.The results of all 16 participants in this key comparison, except for three, are consistent with their key comparisons reference values. The three participants which are outside the KCRV interval are NIM, SMU and NPLI. This comparison may be used to demonstrate core analytical capabilities in accordance with the rules and procedures of the CCQM Gas Analysis Working group.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 (MRA).

The capabilities for the preparation of certified reference materials of carbon monoxide, carbon dioxide, and propane in nitrogen have been compared. The participating national metrology institutes each submitted a gravimetrically prepared gas mixture of a specified target composition typical for the automotive industry to the coordinating laboratory. All mixtures were analyzed by the coordinating laboratory using a gas chromatograph equipped with a thermal conductivity detector in three runs under repeatable conditions. Based on the calibration curve, reference values were assigned to the amount fractions of carbon monoxide, carbon dioxide, and propane. The degrees of equivalence were established as the difference between the gas composition as calculated from preparation and the measured one, and its associated uncertainty. All participants obtained satisfactory results.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 EURAMET, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

The first key comparison on carbon monoxide (CO) in nitrogen dates back to 1992 (CCQM-K1a). It was one of the first types of gas mixtures that were used in an international key comparison. 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 mixtures. Furthermore, in the April 2005 meeting of the CCQM (Consultative Committee for Amount of Substance) Gas Analysis Working Group, a policy was proposed to repeat key comparisons for stable mixtures every 10 years. This comparison was performed in line with the policy proposal and provided an opportunity for NMIs that could not participate in the previous comparison. NMISA from South Africa acted as the pilot laboratory.Of the 25 participating laboratories, 19 (76%) showed satisfactory degrees of equivalence to the gravimetric reference value. The results show that the CO concentration is not influenced by the measurement method used, and from this it may be concluded that the pure CO, used to prepare the gas mixtures, was not 13C-isotope depleted. This was confirmed by the isotope ratio analysis carried out by KRISS on a 1% mixture of CO in nitrogen, obtained from the NMISA.There is no indication of positive or negative bias in the gravimetric reference value, as the results from the different laboratories are evenly distributed on both sides of the key comparison reference value.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 (MRA).

This paper aims to present the developments performed by the Brazilian Metrology Institute (NMI) – Inmetro, considering the environmental demand. Inmetro addresses great part of its activities to the study of the traceability transference based on production and dissemination of certified reference material (CRM) of different areas in chemistry. It will be presented results from certification of the following reference materials developed: BTEX and PAH in solution, besides automotive emission gas mixtures and bioethanol. So, the achievements made are the growth in developing CRM, in order to support the needs of the national industry and to disseminate traceability among the society.

This chapter aims to present the developments performed by the Brazilian Metrology Institute (NMI) – Inmetro, considering the environmental demand. Inmetro addresses a great part of its activities to the study of the traceability transference based on production and dissemination of certified reference material (CRM) of different areas in chemistry. The chapter presents results from certification of the following reference materials developed: BTEX and PAH in solution, besides automotive emission gas mixtures and bioethanol. So, the achievements made are the growth in developing CRM in order to support the needs of the national industry and to disseminate traceability among the society.