When it comes to the calibration of analytical instruments, there are different accreditation levels of calibration labs and certified reference materials. This article helps you understand the main differences between ISO 17034 and ISO 17025, so you can justify the quality of different standards and certified reference materials offered for the calibration of analytical instruments. In order to select the appropriate reference materials, it is necessary to learn more about different types of standards:
ISO 17034 Versus ISO 17025
Working standards are delivered with a factory certificate. They are inexpensive and suitable for rough quality checks, but not officially traceable to the International System of Units (SI). Look for an accreditation logo on the certificate and check whether the supplier is accredited or not.
ISO 17025 calibration laboratories are not allowed to use working standards for calibrations.
ISO 17025-certified standards
ISO 17025-certified standards are traceable to the International System of Units. Suppliers of these standards are accredited according to ISO 17025 and fulfill stringent calibration requirements. Reference value and measurement uncertainty stated on the certificate are guaranteed at the time of calibration but not beyond that. For these standards, neither stability monitoring nor statistical analysis of data are required. The specified uncertainty of ISO 17025 standards refers to the applied reference method. Additional uncertainty contributions have to be considered for stability over lifetime.
ISO 17034-certified reference material
ISO 17034-certified reference material is traceable to the International System of Units and suitable for ISO 17025 calibration laboratories. Unlike ISO 17025, which is concerned with the competence of testing and calibration laboratories in general, ISO 17034 is specifically designed to provide a regular framework for reference material producers. For the characterization of the material, ISO 17025 requirements have to be met as well.
In addition, numerous homogeneity and stability measurements are required, accomplished via statistical methods. Continuous stability monitoring after product release is mandatory for any ISO 17034 reference material. ISO 17034-certified standards guarantee the certified value and the stated measurement uncertainty until the end of the CRM’s lifetime. If available, you should select ISO 17034-certified reference material for calibration of your analytical instrument.