TY - JOUR A1 - Bremser, Wolfram A1 - Becker, Roland A1 - Kipphardt, Heinrich A1 - Lehnik-Habrink, Petra A1 - Panne, Ulrich A1 - Töpfer, Antje T1 - Stability testing in an integrated scheme N2 - ISO Guide 35 deals with RM stability issues and scrutinizes the evaluation of stability testing results under the assumption that either there is no trend at all (a rather rare situation), or any observed deterministic change is insignificant and thus can be neglected. However, market demands for reliable reference materials are obviously not limited to stable or at least seemingly stable materials. In many analytical applications, analytes and measurands under consideration are known, or at least suspected, to be unstable on time scales that may vary widely from measurand to measurand. The Federal Institute for Materials Research and Testing (BAM) has developed (and successfully uses) an integrated approach in its certification practice. The approach is based on an initial stability study and subsequent post-certification monitoring. Data evaluation is model-based and takes advantage of all information collected in the stability testing scheme(s). It thus allows one to deal with any kind of instability observed, to assess limiting time intervals at any stress condition in the range tested, to estimate a final expiry date for materials with detected instabilities or the maximum admissible re-testing interval for seemingly stable materials, and to assess maximum admissible stress loads during delivery of the material to the customer. The article describes (and exemplifies) typical study layout, the model selection, and the integrated data assessment. KW - Certified reference materials KW - Stability KW - Shelf life KW - Arrhenius model KW - ERM PY - 2006 U6 - https://doi.org/10.1007/s00769-006-0152-6 SN - 0949-1775 SN - 1432-0517 VL - 11 IS - 10 SP - 489 EP - 495 PB - Springer CY - Berlin AN - OPUS4-14063 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -