TY - JOUR A1 - Boley, N. A1 - van der Veen, A.M.H. A1 - Robouch, P. A1 - Golze, Manfred A1 - van de Kreeke, Johannes A1 - Örnemark, U. A1 - Tylee, B. T1 - Comparability of PT schemes - what did we learn from COEPT? JF - Accreditation and quality assurance N2 - Abstract The use of proficiency testing schemes (PTS) by laboratories as an integral part of their quality system has been increasing in recent years. Accreditation bodies, regulators and the laboratories’ customers are increasingly using results from PTS in their relationship with laboratories. There are many PTS available in Europe in analytical chemistry; EPTIS indicates over 400. The comparability of these PTS is now a real issue, as many organisers of PTS move into new markets. The COEPT project has systematically demonstrated (in four technical sectors – water, soil, food and occupational hygiene), that there are many similarities between PTS in each sector. For example, nearly all use the z-score as a performance index. One significant difference between many PTS is the value used for the term s in the z-score equation, and this gives a range of evaluations for the same data point. Despite this, the agreement between PTS in the same sector for the evaluation of data is approximately 85%. COEPT has given us a basis for establishing the comparability of PTS and showing us where further harmonisation could occur. KW - Proficiency testing KW - Comparability KW - Harmonisation PY - 2006 SN - 0949-1775 SN - 1432-0517 VL - 11 IS - 8-9 SP - 391 EP - 399 PB - Springer CY - Berlin AN - OPUS4-14162 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - van de Kreeke, Johannes A1 - de la Calle, B. A1 - Held, A. A1 - Bercaru, O. A1 - Ricci, M. A1 - Shegunova, P. A1 - Taylor, P. T1 - IMEP-23: The eight EU-WFD priority PAHs in water in the presence of humic acid JF - Trends in analytical chemistry N2 - Recently, the International Measurement Evaluation Programme (IMEP) organized an interlaboratory comparison on total concentrations of eight polycyclic aromatic hydrocarbons (PAHs) in natural inland waters. It was carried out in support to the European Union Water Framework Directive (EU-WFD) that lists these eight as priority substances. As sample matrix, we used groundwater spiked with humic acid as a model for the colloidal substances that are present in natural inland waters. Humic substances can adsorb PAHs, but we found that some laboratories did not apply analytical procedures that sufficiently accounted for this. One of these laboratories was involved in establishing the reference values. We show how this impacted on the reliability of their measurements. Many participants accepted our invitation to report their measurement uncertainties. We assessed their results against our reference values and uncertainties, and provided z and zeta scores. Although the overall measurement capability appears satisfactory, there is room for improvement of analytical procedures as regards the use of measurement standards. KW - Dissolved organic matter (DOM) KW - Humic substance KW - Interlaboratory comparison (ILC) KW - Internal standard KW - International measurement evaluation programme (IMEP) KW - Polycyclic aromatic hydrocarbon (PAH) KW - Reference value KW - Uncertainty KW - Water KW - Water framework directive (WFD) PY - 2010 DO - https://doi.org/10.1016/j.trac.2010.04.009 SN - 0165-9936 SN - 0703-7147 VL - 29 IS - 8 SP - 928 EP - 937 PB - Elsevier CY - Amsterdam AN - OPUS4-21865 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Baer, I. A1 - van de Kreeke, Johannes A1 - Linsinger, T.P.J. A1 - Robouch, P. A1 - Raposo, F.C. A1 - de la Calle, B. T1 - IMEP-24 analysis of eight trace elements in toys JF - Trends in analytical chemistry N2 - The International Measurement Evaluation Program (IMEP) organized the IMEP-24 interlaboratory comparison after reports in the media about high levels of lead in toys. The aim of this comparison was to verify the laboratories' capacity to evaluate trace-element levels in a possible toy-like material according to the European Standard EN 71-3:1994. As test material, it used a former certified reference material containing levels of antimony, arsenic, barium, cadmium, chromium, mercury, lead and selenium around the limits set in the standard. Four expert laboratories confirmed the reference values (Xref) for all elements but Hg, and established a reference value for Hg. The scatter of the results reported by the participants was large, as expected, but showed a close to normal distribution around the reference values for five of the eight trace elements. The spread of results was mainly attributed to sampling and sample preparation. One major issue observed in this exercise was the lack of legislative rules about how to report the result, or, more specifically, the use of the analytical correction, which was introduced in EN 71-3:1994 to achieve consistent interpretation of results and which is to be applied when values are equal to or above the maximum limits set in the standard. Its application by the participants was very inconsistent and led to problems in their evaluation. There is clearly a need for clarification and for more formal regulations with regard to result reporting in order to minimize the risk of confusion. Participants were also asked to give their opinion with regard to the acceptability of the test material for the market. The majority correctly considered the material as non-compliant. However, almost one-third incorrectly assessed the material as compliant. KW - Analytical correction KW - European Standard EN 71-3:1994 KW - Interlaboratory comparison KW - International Measurement Evaluation Program (IMEP) KW - Lead in toys KW - Toy safety KW - Trace element PY - 2011 DO - https://doi.org/10.1016/j.trac.2010.09.007 SN - 0165-9936 SN - 0703-7147 VL - 30 IS - 2 SP - 313 EP - 323 PB - Elsevier CY - Amsterdam AN - OPUS4-23862 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - van de Kreeke, Johannes T1 - EPTIS update JF - Accreditation and quality assurance PY - 2003 SN - 0949-1775 SN - 1432-0517 VL - 8 IS - 6 PB - Springer CY - Berlin AN - OPUS4-4394 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - van de Kreeke, Johannes T1 - EPTIS und COEPT - European Initiatives with Worldwide Relevance JF - CITAC News : Cooperation in international traceability in analytical chemistry PY - 2006 IS - February SP - 7 EP - 8 CY - Jerusalem, Israel AN - OPUS4-12260 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - van de Kreeke, Johannes T1 - EPTIS for the new Member States T2 - IRMM Workshop T2 - IRMM Workshop CY - Budapest, Hungary DA - 2004-10-13 PY - 2004 AN - OPUS4-4958 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - van de Kreeke, Johannes T1 - EPTIS for Latin America T2 - IAAC Workshop T2 - IAAC Workshop CY - São Paulo, Brazil DA - 2004-09-21 PY - 2004 AN - OPUS4-4959 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Örnemark, U. A1 - Fostel, H. A1 - Straub, R. A1 - van de Kreeke, Johannes T1 - Policies, requirements and surveys concerning frequency for participation in proficiency testing schemes JF - Accreditation and quality assurance N2 - This paper focuses on policies and requirements concerning the frequency for participation in proficiency testing (PT) and provides an overview of the frequency for which PT activities are offered in 25 testing fields. Recent international surveys are summarised. KW - Proficiency testing KW - External quality assessment KW - Frequency KW - Accreditation KW - Policy documents KW - Eptis PY - 2004 DO - https://doi.org/10.1007/s00769-004-0858-2 SN - 0949-1775 SN - 1432-0517 IS - 9 SP - 729 EP - 732 PB - Springer CY - Berlin AN - OPUS4-5198 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - van de Kreeke, Johannes T1 - Statistics for ILCs with few participants -some differences- T2 - EQALM-Workshop T2 - EQALM-Workshop CY - Copenhagen, Denmark DA - 2012-10-25 PY - 2012 AN - OPUS4-27381 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - van de Kreeke, Johannes T1 - DIN EN ISO/IEC 17043:2010 Konformitätsbewertung - Allgemeine Anforderungen an Eigungsprüfungen T2 - Jahrestagung VUP T2 - Jahrestagung VUP CY - Neckarsulm, Germany DA - 2012-09-13 PY - 2012 AN - OPUS4-27382 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -