Why a reference with a calibration certificate is not necessarily a CRM

Instrument qualification using CRMs from an appropriately accredited supplier is the first step towards data integrity. Indeed, the choice of CRM supplier is as important as the choice of CRM.
A supplier’s Schedule of Accreditation should be checked to confirm that it includes the reference material to be purchased - it may not,  
Furthermore, it is now recommended that instrument qualification measurements are conducted over the operational range required for the analysis. A laboratory performing measurements over a wide wavelength or photometric range will likely require several different CRMs to cover each instrument parameter.  
According to ISO, a fully accredited CRM supplier should be accredited to both ISO 17034:2016 and ISO/IEC 17025:2017 Standards.   
In 2001, Starna Scientific became the first company worldwide to achieve ISO/IEC 17025 accreditation for the calibration of liquid and glass CRMs for UV-visible spectrophotometry, and in 2006, the company became the first and only supplier of spectrophotometry references accredited to both standards.  
All Starna’s CRMs are supplied with a certificate showing the traceability of the certified value to Standard Reference Materials (SRM) and a statement of the measurement uncertainty, as required by the ISO definition of a CRM. 
Starna Scientific are committed to the process of continuous improvement demanded by those standards and look forward to another 20 years as the preferred supplier to many of the leading pharmaceutical companies, instrument manufacturers and accredited laboratories worldwide.  
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