• Certified Reference
  • Accreditation to ISO/IEC 17025 and ISO Guide 34, also called Double Accreditation, represents the pinnacle of quality system achievement and allows the credible production and testing of Certified Reference Materials (CRMs). (sigmaaldrich.com)
  • Note - Beginning June 15, 2015, customers will see a change in the accreditation symbols found on the Certificate of Analysis (COA) for Certified Reference Materials (CRMs)and Proficiency Testing samples (PTs) sold under Sigma-Aldrich US based CRM producers. (sigmaaldrich.com)