TY - JOUR A1 - Urquiza, M.P. A1 - Torres, M.M. A1 - Mitani, Y. A1 - Schantz, M.M. A1 - Duewer, D.L. A1 - May, W.E. A1 - Parris, R.M. A1 - Wise, S. A. A1 - Kaminski, Katja A1 - Philipp, Rosemarie A1 - Win, Tin A1 - Rosso, A. A1 - Kim, D.H. A1 - Ishikawa, K. A1 - Krylov, A.I. A1 - Kustikov, Y.A. A1 - Baldan, A. T1 - Final report on CCQM-K47: Volatile organic compounds in methanol N2 - KEY COMPARISON At the October 2005 CCQM Organic Analysis Working Group Meeting (IRMM, Belgium), the decision was made to proceed with a Key Comparison study (CCQM-K47) addressing the calibration function for the determination of volatile organic compounds (VOCs) used for water quality monitoring. This was coordinated by CENAM and NIST. Benzene, o-xylene, m-xylene and p-xylene were chosen as representative VOCs. The solvent of choice was methanol. Key Comparison CCQM-K47 demonstrated the capabilities of participating NMIs to identify and measure the four target VOCs in a calibration solution using GC-based methods. The measurement challenges in CCQM-K47, such as avoiding volatility loss, achieving adequate chromatographic resolution and isolating potential interferences, are typical of those required for value-assigning volatile reference materials. Participants achieving comparable measurements for all four VOCs in this Key Comparison should be capable of providing reference materials and measurements for VOCs in solutions when present at concentration levels greater than 10 µg/g. PY - 2013 DO - https://doi.org/10.1088/0026-1394/50/1A/08021 SN - 0026-1394 SN - 1681-7575 VL - 50 SP - 08021, 1 EP - 24 PB - Inst. of Physics Publ. CY - Bristol AN - OPUS4-31071 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Richter, Matthias A1 - Baldan, A. A1 - Beelen, R. A1 - de Boed, E. J.J. A1 - Tuma, Dirk A1 - Kipphardt, Heinrich A1 - Wilke, Olaf A1 - van der Veen, A. M.H. T1 - Primary gas standards for the determination of sulfur-based impurities at trace level in hydrogen N2 - Hydrogen fuel quality needs to comply with ISO 14687:2025 to avoid harmful impact on applications using proton-exchange membrane (PEM) fuel cells. For total sulfur as one of the most impactful contaminants, an amount fraction of 4 nmol/mol has been set as threshold (so-called Grade D quality). In this study, novel gaseous primary gas standards (PGS) of seven sulfur compounds were prepared either gravimetrically at 1000 nmol/mol, 100 nmol/mol, and 10 nmol/mol, or dynamically diluted down to 4 nmol/mol in hydrogen and argon matrices with relative expanded uncertainties well below 10 % (k = 2) and proven stability of at least 9–12 months. Two different cylinder passivation treatments were compared, with one treatment identified as unsuitable since reactions took place within the mixture. By performing a cross-check study, equivalence between both sets of PGS could be demonstrated (≤ 5 % relative deviation for most of the sulfur species). KW - Hydrogen quality KW - ISO 14687 KW - Sulfur impurities KW - Primary gas standards KW - TD-GC/SCD PY - 2026 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-656759 DO - https://doi.org/10.1016/j.ijhydene.2026.154461 SN - 0360-3199 VL - 224 SP - 1 EP - 13 PB - Elsevier Ltd. AN - OPUS4-65675 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - de Krom, I. A1 - Heikens, D. A1 - Horn, Wolfgang A1 - Wilke, Olaf A1 - Richter, Matthias A1 - Baldan, A. T1 - Metrological generation of SI-traceable gas-phase standards and reference materials for (semi-) volatile organic compounds N2 - EN 16516 sets specifications for the determination of emissions into indoor air from construction products. Reliable, accurate and International System of Unit (SI)-traceable measurement results of the emissions are the key to consumer protection. Such measurement results can be obtained by using metrologically traceable reference materials. Gas-phase standards of volatile organic compounds (VOCs) in air can be prepared by a variety of dynamic methods according to the ISO 6145 series. However, these methods are not always applicable for semi-VOCs (SVOCs) due to their high boiling point and low vapour pressure. Therefore, a novel dynamic gas mixture generation system has been developed. With this system gas-phase standards with trace level VOCs and SVOCs in air can be prepared between 10 nmol mol−1 and 1000 nmol mol−1. The VOCs and SVOCs in this study have normal boiling points ranging from 146 °C to 343 °C. Metrologically traceable reference materials of the gas-phase standard were obtained by sampling of the VOC gas-phase standard into Tenax TA® sorbent material in SilcoNert® coated stainless steel tubes. Accurately known masses between 10 ng and 1000 ng per VOC were sampled. These reference materials were used to validate the dynamic system. Furthermore, the storage and stability periods of the VOCs in the reference materials were determined as these are crucial characteristics to obtain accurate and SI-traceable reference materials. In a round robin test (RRT), the reference materials were used with the aim of demonstrating the feasibility of providing SI-traceable standard reference values for SVOCs for interlaboratory comparison purposes. Based on the results from the validation, the storage and stability studies and the RRT, gas-phase standards and reference materials of VOCs and SVOCs with relative expanded uncertainties between 5% and 12% (k = 2) have been developed. These reference standards can be used as calibrants, reference materials or quality control materials for the analysis of VOC emissions. KW - SVOC KW - Dynamic calibration gas mixtures KW - Reference materials KW - Indoor air KW - Thermal desorption PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-565978 DO - https://doi.org/10.1088/1361-6501/aca704 VL - 34 IS - 3 SP - 1 EP - 13 PB - IOP Publishing AN - OPUS4-56597 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -