PD 6461-4-2004 (2010) PDF

Full title and description

STB PD 6461-4-2004 (2010) — General metrology. Part 4: Practical guide to measurement uncertainty. This published document reproduces PD 6461-4:2004 (BSI) and provides a practical, worked approach for evaluating and reporting the uncertainty associated with measurement results; it follows the principles of the Guide to the Expression of Uncertainty in Measurement (the GUM).

Abstract

This document is a practical handbook for applying the GUM methodology to industrial and laboratory measurement problems where a mathematical model links the measurand to input (influence) quantities. It describes Type A and Type B uncertainty evaluation, combining standard uncertainties, propagation (sensitivity coefficients and linearisation), and formulation of an uncertainty budget, with illustrative examples and an extended worked example in an annex. The document was originally published in 2004 and was later confirmed in 2010.

General information

• Status: Confirmed / active (published document; shown as confirmed in 2010).
• Publication date: 20 August 2004 (PD 6461-4:2004); confirmation recorded January 2010.
• Publisher: British Standards Institution (BSI) — published as PD 6461-4:2004.
• ICS / categories: 01.040.17 (Metrology and measurement — physical phenomena), 17.020 (Metrology and measurement in general).
• Edition / version: PD 6461-4:2004 (confirmed 2010); often listed with national adoption identifiers (e.g., STB prefix in some catalogues).
• Number of pages: 46 pages.

Scope

The published document provides procedures for evaluating the uncertainty of a measurement result when a measurement model (a formula relating the measurand to input quantities) is available. It is intended as a practical guide for measurement professionals and laboratories applying the GUM approach; it does not attempt to replace the full theoretical treatment in the GUM where a more rigorous statistical analysis or reproducibility studies are required. Examples and an annex demonstrate the step‑by‑step construction of an uncertainty budget and reporting conventions.

Key topics and requirements

• Overview of GUM principles and relationship to PD 6461 series and JCGM/GUM guidance.
• Type A (statistical) and Type B (non‑statistical) evaluations of standard uncertainty.
• Assignment and use of probability distributions (rectangular, triangular, normal, two‑valued) for input quantities.
• Propagation of uncertainties via sensitivity coefficients and linearisation of the measurement model; combined standard uncertainty and expanded uncertainty (coverage factors).
• Preparation of an uncertainty budget, worked examples and an extended annex illustrating application to industrial measurement problems.
• Cross‑references and guidance for cases needing more advanced treatment (supplements and related technical documents such as ISO/JCGM guidance).

Typical use and users

Used by calibration and testing laboratories, metrologists, quality assurance engineers, instrument manufacturers, and technical specialists who must evaluate and report measurement uncertainty for compliance, calibration statements, test reports, and product verification. The guide is particularly useful where measurement results are obtained from formulaic measurement models (rather than solely from interlaboratory reproducibility studies).

Related standards

Key related documents include other parts of the PD 6461 series (for example PD 6461‑1 and PD 6461‑3), ISO/JCGM GUM (JCGM 100 / ISO/IEC Guide 98‑3), and related supplements (e.g., JCGM 101 — Monte Carlo supplement) and ISO/TS guidance referenced in the PD cross‑references. These provide the foundational principles and, where needed, alternative computational approaches.

Keywords

measurement uncertainty, GUM, PD 6461, uncertainty budget, Type A evaluation, Type B evaluation, sensitivity coefficients, expanded uncertainty, metrology, calibration

FAQ

Q: What is this standard?

A: It is the Published Document PD 6461-4:2004 titled "General metrology — Part 4: Practical guide to measurement uncertainty", presented here with the STB catalog identifier STB PD 6461-4-2004 (2010) where applicable. It provides a practical, worked guide for evaluating measurement uncertainty following the GUM principles.

Q: What does it cover?

A: Procedures for evaluating, combining and reporting uncertainty of measurement when a mathematical model relates the measurand to input quantities; Type A and Type B evaluations; selection of probability distributions; propagation via sensitivity coefficients and linearisation; construction of an uncertainty budget and examples.

Q: Who typically uses it?

A: Calibration and testing laboratories, metrologists, measurement engineers, instrument manufacturers and quality/validation specialists who need to produce traceable measurement results with quantified uncertainty.

Q: Is it current or superseded?

A: The document was published in 2004 (PD 6461-4:2004) and is recorded as confirmed in 2010 in catalog listings; it remains a practical guidance document referenced alongside the JCGM/ISO GUM family. Users should check their national standards body or the publisher (BSI) for the very latest status or any subsequent revisions or national adoptions.

Q: Is it part of a series?

A: Yes — it is part of the PD 6461 series of documents on general metrology and measurement uncertainty; it cross‑references other PD 6461 parts and international guidance (the GUM and related supplements).

Q: What are the key keywords?

A: measurement uncertainty, GUM, uncertainty budget, Type A, Type B, sensitivity coefficient, expanded uncertainty, calibration.