What is Traceability?

In our terms, we refer back to two definitions: • NIST - Traceability can be established as an nonstop record of documentation ("documentation traceability") or an nonstop chain of measurements and associated uncertainties ("metrological traceability"). As applied here, the word "traceability" always means "metrological traceability." • ISO 17025 - “property of a measurement result whereby the result can be related to a reference through a documented unbroken chain of calibrations, each contributing to the measurement uncertainty” PurityPlus® specialty gases’ specifications are traceable back to NIST’s Standard Reference Materials where such analogous gas standards exist. When particular SRM’s do not exist, equivalent commensurate standards are used, either directly sourced from another chosen national government agency outside the US, or by having a gas standard analyzed and certified by NIST or other designated entity.