TY - JOUR A1 - Pogány, A. A1 - Balslev-Harder, D. A1 - Braban, Ch. F. A1 - Cassidy, N. A1 - Ebert, V. A1 - Ferracci, V. A1 - Hieta, T. A1 - Leuenberger, D. A1 - Martin, N. A. A1 - Pascale, C. A1 - Peltola, J. A1 - Persijn, S. A1 - Tiebe, Carlo A1 - Twigg, M. M. A1 - Vaittinen, Olavi A1 - van Wijk, J. A1 - Wirtz, K. A1 - Niederhauser, B. T1 - A metrological approach to improve accuracy and reliability of ammonia measurements in ambient air N2 - The environmental impacts of ammonia (NH3) in ambient air have become more evident in the recent decades, leading to intensifying research in this field. A number of novel analytical techniques and monitoring instruments have been developed, and the quality and availability of reference gas mixtures used for the calibration of measuring instruments has also increased significantly. However, recent inter-comparison measurements show significant discrepancies, indicating that the majority of the newly developed devices and reference materials require further thorough validation. There is a clear need for more intensive metrological research focusing on quality assurance, intercomparability and validations. MetNH3 (Metrology for ammonia in ambient air) is a three-year project within the framework of the European Metrology Research Programme (EMRP), which aims to bring metrological traceability to ambient ammonia measurements in the 0.5–500 nmol mol−1 amount fraction range. This is addressed by working in three areas: (1) improving accuracy and stability of static and dynamic reference gas mixtures, (2) developing an optical transfer standard and (3) establishing the link between high-accuracy metrological standards and field measurements. In this article we describe the concept, aims and first results of the project. KW - Ammonia in ambient air KW - Traceability KW - Reference gas standards KW - Optical transfer standard KW - Validation and testing infrastructure PY - 2016 DO - https://doi.org/10.1088/0957-0233/27/11/115012 SN - 0957-0233 VL - 27 IS - 11 SP - 115012 EP - 115026 PB - IOP Publishing Ltd. AN - OPUS4-39130 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - van der Hout, J. W. A1 - van der Veen, A. M. H. A1 - Ziel, P. R. A1 - Kipphardt, Heinrich A1 - Tuma, Dirk A1 - Maiwald, Michael A1 - Fernández, T. E. A1 - Gómez, C. A1 - Cieciora, D. A1 - Ochman, G. A1 - Dias, F. A1 - Silvino, V. A1 - Macé, T. A1 - Sutour, C. A1 - Marioni, F. A1 - Ackermann, A. A1 - Niederhauser, B. A1 - Fükő, J. A1 - Büki, T. A1 - Szilágyi, Z. N. A1 - Tarhan, T. A1 - Engin, E. T1 - International Comparison Euramet.QM-K111 – Propane in Nitrogen N2 - This key comparison aims to assess the core capabilities of the participants in gas analysis. Such competences include, among others, the capabilities to prepare Primary Standard gas Mixtures (PSMs), perform the necessary purity analysis on the materials used in the gas mixture preparation, the verification of the composition of newly prepared PSMs against existing ones, and the capability of calibrating the composition of a gas mixture. According to the Strategy for Key Comparisons of the Gas Analysis Working Group, this key comparison is classified as an RMO track A key comparison. The artefacts were binary mixtures of propane in nitrogen at a nominal amount-of-substance fraction level of 1000 μmol/mol. The values and uncertainties from the gravimetric gas mixture preparation were used as key comparison reference values (KCRVs). Each transfer standard had its own KCRV. The results are generally good. All results are within ± 1 % of the KCRV. KW - EURAMET.QM-K111 KW - Propane in nitrogen PY - 2017 DO - https://doi.org/10.1088/0026-1394/54/1A/08020 SN - 0026-1394 VL - 54 IS - Technical Supplement SP - 08020, 1 EP - 34 PB - IOP Science AN - OPUS4-44471 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Oudwater, R. J. A1 - van Wijk, J. I. T. A1 - Persijn, S. A1 - Wessel, R. M. A1 - van der Veen, A. M. H. A1 - Mace, T. A1 - Sutour, C. A1 - Couette, J. A1 - Milton, M. A1 - Harling, A. A1 - Vargha, G. A1 - Uprichard, I. A1 - Haerri, H.-P. A1 - Niederhauser, B. A1 - Tuma, Dirk A1 - Maiwald, Michael A1 - Boissière, Claudia T1 - Final report on EURAMET QM-S8: Analysis of impurities in pure and balance gases used to prepare primary standard gas mixtures by the gravimetric method N2 - This project concerns the purity analysis of nitrogen as used in reference gas mixture preparation. This project was carried out without adding impurities to the gas used for this comparison, and is therefore more representative to evaluate the analysis of CO, CO2, CH4, O2, Ar and H2O impurities in high purity nitrogen. The analysis of the amount–of–substance fraction water was optional. Two 50 litre high purity nitrogen cylinders were purchased from a well-qualified supplier of specialty gases. The listed components were expected to be present in the pure nitrogen at the target levels as a result of the purification of the nitrogen. From the start of this comparison it was clear that the comparison may not lead to reference values for the constituents analysed. The results indicate that analyses of high purity gases are often limited by the limits of detection of analytical equipment used. The reports of the participating laboratories also indicate that there is no agreed method of determination of the uncertainty on a detection Limit value. The results provide useful information on the Performance of participants. For all analysed components there is reasonable agreement in results for LNE, VSL, Metas and NPL. For BAM only the Argon result is in agreement. KW - Gas analysis KW - Nitrogen KW - Purity analysis PY - 2013 DO - https://doi.org/10.1088/0026-1394/50/1A/08023 SN - 0026-1394 SN - 1681-7575 VL - 50 IS - 08023 SP - 1 EP - 58 PB - Institute of Physics Publishing CY - Bristol AN - OPUS4-35896 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -