TABLE OF CONTENTS As any output from laboratories (may it be in the form of analytical data, products, or documents) must be considered a product that is made to satisfy the customer, quality has become a key component in the operation of laboratories world-wide. As in manufacturing, quality assurance (QA) is being built into the daily operations of the laboratory through systems of quality control (QC) and total quality management (TQM). For the production of measurement data, these systems must also address accuracy, precision, and reliability of the data. It has become an accepted wisdom that the use of reference materials and certified reference materials provides a solid foundation for the assessment and control of the quality of a laboratory s output.
The definition for a Certified Reference Material (CRM) is given in the ISO Guide 30 (ISO 1992):
Reference material, accompanied by a certificate, one or more of whose property values are certified by a procedure which establishes its traceability to an accurate realization of the unit in which the property values are expressed, and for which each certified value is accompanied by an uncertainty at a stated level of confidence.
Additionally, there is also a definition for a Reference Material (RM):
Material or substance, one or more of whose property values are sufficiently homogeneous and well established to be used in calibration of an apparatus, the assessment of a measurement method, or for assigning values to materials.
