Knowledge

Metrology Dictionary

The complete VIM vocabulary — all numbered concepts of JCGM 200:2012 as faithful paraphrases with clause citations — plus clearly labeled practice terms from the GUM, ILAC, ISO and NIST guidance.

Primary measurement standard

A standard established using a primary reference measurement procedure, or created as an artifact chosen by convention — not calibrated against another standard for the same quantity.

VIM (JCGM 200:2012) 5.4 · Standards & Units

Primary reference measurement procedure

A reference procedure used to obtain a result without relation to a standard for a quantity of the same kind — the route by which primary standards are realized.

VIM (JCGM 200:2012) 2.8 · General

Process measurement assurance

A program of intermediate checks using check standards and control charts to demonstrate that a measurement process remains in statistical control between calibrations, as described in NIST SOP 30.

NIST SOP 30 (2019) · Quality & Accreditation

Proficiency testing

Evaluation of participant performance against pre-established criteria by means of interlaboratory comparisons — an ISO/IEC 17025 requirement for demonstrating ongoing competence.

ISO/IEC 17043:2023 · Quality & Accreditation