In QC testing, a material having an accepted reference value used to determine the accuracy of a measurement system.
- Note: A check standard is preferably a material that is either a certified reference material with traceability to a nationally recognized body or a material that has an accepted reference value established through interlaboratory testing.
- Note: For some measurement systems, a pure, single component material having known value or a simple gravimetric or volumetric mixture of pure components having calculable value may serve as a check standard.
- Note: Users should be aware that for measurement systems that show matrix dependencies, accuracy determined from pure compounds or simple mixtures may not be representative of that achieved on actual samples.