Dictionary · Calibration
Metrological traceability to a measurement unit
Traceability whose stated reference is the definition of a unit through its practical realization — "traceable to the SI" in its precise sense.
Related terms
More from Calibration
Metrological traceability chain
The sequence of standards and calibrations used to relate a result to a stated reference — the concrete path behind a traceability claim.
VIM (JCGM 200:2012) 2.42
Metrological comparability of measurement results
Comparability of results traceable to the same reference — what shared traceability buys: results that can be meaningfully compared even from different labs and methods.
VIM (JCGM 200:2012) 2.46
Adjustment of a measuring system
The set of operations carried out on a measuring system so that it provides prescribed indications corresponding to given quantity values. Adjustment changes the instrument; calibration afterwards re-establishes its relation to standards.
VIM (JCGM 200:2012) 3.11
As-found / as-left data
Calibration results recorded before (as-found) and after (as-left) any adjustment or repair. As-found data support reverse-traceability decisions about product accepted with the instrument since its previous calibration.
Calibration practice; NCSLI RP-1
Verification
Provision of objective evidence that a given item fulfils specified requirements — e.g. that an instrument performs within its maximum permissible errors. A pass/fail attestation, distinct from calibration.
VIM (JCGM 200:2012) 2.44
Calibration
The operation that, under specified conditions, first establishes a relation between values (with uncertainties) provided by measurement standards and corresponding indications (with uncertainties), and second uses that information to obtain results from indications. Calibration is not adjustment.
VIM (JCGM 200:2012) 2.39