Proficiency Testing — Slip Gauge(Interlaboratory Comparison — Gauge Block Comparison)
ISO/IEC 17043-aligned proficiency testing scheme for slip gauge (gauge block) calibration — circulated reference artefacts, ISO 13528 statistical evaluation (En / z-scores), and confidential performance reports for NABL-accredited and aspiring calibration laboratories.
What is the Proficiency Testing — Slip Gauge Scheme?
Under ISO/IEC 17025:2017 (clause 7.7), every accredited calibration laboratory must monitor the validity of its results by participating in proficiency testing (PT) — and NABL expects documented, satisfactory PT participation across the accredited scope. Global Lab operates an ISO/IEC 17043:2023-aligned interlaboratory comparison scheme for slip gauge (gauge block) calibration: a characterised artefact travels between participating labs, each calibrates it by their normal method, and results are evaluated statistically against the assigned reference value.
Gauge blocks are the atoms of dimensional metrology — micro-level disagreement here scales into every calibration a lab performs with them. The scheme measurand covers calibration of slip gauges by comparison against reference blocks, with results reported at the circulated block set's nominal lengths. Each participant receives a confidential performance report — En numbers and z-scores per ISO 13528 — through our Live PT Program portal, with anonymised group statistics and corrective-action guidance where performance flags arise.
How the Proficiency Testing — Slip Gauge is Conducted
- 1
Enrolment
The laboratory enrols for the slip gauge (gauge block) scheme round through the Live PT Program portal and receives the scheme protocol. - 2
Artefact Receipt
The characterised artefact arrives per the circulation schedule with handling instructions and condition-check requirements. - 3
Calibration by Your Method
Your lab calibrates the circulated gauge blocks by its normal comparison method and reports central length deviations with uncertainties. - 4
Result Submission
Results with claimed uncertainties are submitted through the portal by the round deadline. - 5
Statistical Evaluation
Submissions are evaluated against the assigned value per ISO 13528 — En numbers and z-scores computed per measurement point. - 6
Performance Report
A confidential report with your performance flags and anonymised group statistics is issued; corrective-action guidance follows any unsatisfactory result.
Applicable Test Standards
| Standard | Title | Scope | Type |
|---|---|---|---|
| ISO/IEC 17043:2023 | Conformity Assessment — General Requirements for the Competence of Proficiency Testing Providers | PT Scheme Operation | International |
| ISO 13528:2022 | Statistical Methods for Use in Proficiency Testing by Interlaboratory Comparison | En / z-Score Evaluation | International |
| ISO/IEC 17025:2017 | Competence of Testing and Calibration Laboratories (Clause 7.7) | Participation Requirement | International |
| ISO 3650 | Geometrical Product Specifications — Length Standards — Gauge Blocks | Gauge Block Requirements | Method Standard |