Certified Reference Materials are characterized by a metrologically valid procedure for one or more specified properties, accompanied by a certificate that provides the value of the specified property, its associated uncertainty, and a statement of metrological traceability.

It is not enough that a CRM is characterised with a result at the time of manufacture, but that that result is maintained throughout the period of validity of the CRM, or shelf-life, within the defined storage parameters. Furthermore, the effects of temperature extremes during transport must be assessed. The results of these assessments must be reflected in the uncertainty estimate associated with the calibration result of the CRM.

Under ISO 17025, testing laboratories should demonstrate their confidence in the stability, homogeneity and storage of their CRMs. ISO Guide 34 is the accepted international standard for the competence of reference material producers. Not only does it cover the metrological and traceability requirements of ISO 17025 but also requires assessments of stability, storage and homogeneity of CRMs.

Our partner Altus Science is accredited by the United Kingdom Accreditation Service (UKAS) as a provider of certified reference material (CRM) products. Altus operates to ISO 17025 as a Testing Laboratory (Laboratory ID: 8020) and ISO Guide 34 as a CRM provider.