DIN EN ISO/IEC 17025:2005 General requirements for the competence of testing and calibration laboratories (ISO/IEC 17025:2005); German and English version EN ISO/IEC 17025:2005
DIN ISO 5725-2:2002 Accuracy (trueness and precision) of measurement methods and results - Part 2: Basic method for the determination of repeatability and reproducibility of a standard measurement method (ISO 5725-2:1994 including Technical Corrigendum 1:2002)
ISO 1573:1980 Tea; Determination of loss in mass at 103 degrees C