Current Edition Checked October 24, 2026
Traceability is a property of a measurement result, not of an instrument or a laboratory, and NIST does not certify other parties’ claims of traceability.
What It Covers
What it means for a calibration or measurement result to be traceable: related to a stated reference, usually the SI through a national metrology institute such as NIST, by a documented, unbroken chain of calibrations, each contributing to the measurement uncertainty.
Who It Applies To
Anyone whose quality system, regulator, or customer requires calibrated equipment — which is nearly every regulated manufacturer and laboratory.
Key Requirements
- A documented, unbroken chain of calibrations back to a national or international standard.
- A stated measurement uncertainty at each step of the chain.
- Calibration suppliers whose competence is demonstrated, normally by ISO/IEC 17025 accreditation with the calibration in scope.
- Records that identify the standards used and their own calibration status.
What an Auditor Asks to See
- Calibration certificates showing results, uncertainty, and the standards used.
- Evidence the calibration supplier is accredited for that parameter and range.
- What was done when a standard was later found out of tolerance.
Where Systems Fall Short
- Certificates that say “NIST traceable” with no uncertainty or standards listed.
- No impact assessment when an instrument is found out of tolerance.
How QES Helps
Calibration programs with supplier scopes checked, uncertainties stated, and out-of-tolerance impact assessed.
Related Standards
Sources. NIST — Metrological traceability (opens in a new tab); BIPM — Joint Committee for Guides in Metrology (opens in a new tab). Status checked October 24, 2026. This page summarizes NIST Traceability; it does not reproduce or replace it. Buy the standard from its publisher, or read the regulation in its official text, before relying on a detail. Not legal advice.