Overview

ISO/TR 14253-6:2012 is a Technical Report in the Geometrical Product Specifications (GPS) family that expands decision‑rule options for acceptance and rejection based on measurement. Building on the default rule in ISO 14253‑1, this document introduces generalized decision rules and terminology to support industrial situations where the default (very conservative) acceptance rule may not be economically optimal. It is informative guidance (Technical Report) that helps organizations agree, communicate and implement alternative decision rules while explicitly addressing measurement uncertainty in acceptance/rejection decisions.

Key topics and requirements

Decision rules - formalizes how measurement uncertainty is allocated when making acceptance/rejection decisions for a single metrological characteristic.
Guard bands - defines intervals between specification (tolerance) limits and acceptance limits; introduces stringent and relaxed acceptance/rejection concepts.
Acceptance zone / Rejection zone / Transition zone - terminology and requirements for setting these intervals in measurement-based inspection.
Measurement capability index (Cm) - defined in the report as Cm = T / (4·u) for a two‑sided tolerance of width T and standard measurement uncertainty u (document uses a multiple of 4).
Process capability index (Cp) - special-case definition used in the report (zone width divided by 6 standard deviations of production distribution).
Producer’s risk / Consumer’s risk - probabilistic metrics used to express chances of incorrect decisions under a given decision rule.
Examples and guidance - illustrative decision‑rule scenarios (e.g., different Cp and Cm cases) and worked examples to support selection and communication of alternative rules.
Communication and agreement - requirements that decision rules differing from ISO 14253‑1 be agreed by involved parties (designer, metrologist, management, customer/manufacturer).

Note: ISO/TR 14253‑6 does not prescribe how to quantify economic costs of decision outcomes - that remains a business/management responsibility.

Practical applications and users

This Technical Report is useful for:

Metrologists and calibration labs defining acceptance/rejection criteria for inspection equipment and gauging.
Quality engineers and production managers who need to balance measurement uncertainty, process capability and economic outcomes.
Designers and customers who must agree on the functional implications of tolerances and decision rules.
Suppliers and contract manufacturers implementing agreed inspection rules and documenting acceptance limits and guard bands.

Practical uses include specifying gauging limits, documenting acceptance criteria in procurement or quality agreements, and choosing decision rules that trade off producer’s and consumer’s risk according to business priorities.

Related standards

ISO 14253‑1: Decision rules (default)
ISO 14978: GPS measuring equipment
ISO 17450‑2: GPS basic tenets and uncertainties
ISO 21747: Process capability statistics
ISO/IEC Guide 98‑3 (GUM) and ISO/IEC Guide 99 (VIM)

Keywords: ISO/TR 14253‑6:2012, GPS decision rules, measurement uncertainty, guard band, acceptance zone, rejection zone, measurement capability Cm, process capability Cp, producer’s risk, consumer’s risk, metrology.

Overview

Key topics and requirements

Decision rules - formalizes how measurement uncertainty is allocated when making acceptance/rejection decisions for a single metrological characteristic.
Guard bands - defines intervals between specification (tolerance) limits and acceptance limits; introduces stringent and relaxed acceptance/rejection concepts.
Acceptance zone / Rejection zone / Transition zone - terminology and requirements for setting these intervals in measurement-based inspection.
Measurement capability index (Cm) - defined in the report as Cm = T / (4·u) for a two‑sided tolerance of width T and standard measurement uncertainty u (document uses a multiple of 4).
Process capability index (Cp) - special-case definition used in the report (zone width divided by 6 standard deviations of production distribution).
Producer’s risk / Consumer’s risk - probabilistic metrics used to express chances of incorrect decisions under a given decision rule.
Examples and guidance - illustrative decision‑rule scenarios (e.g., different Cp and Cm cases) and worked examples to support selection and communication of alternative rules.
Communication and agreement - requirements that decision rules differing from ISO 14253‑1 be agreed by involved parties (designer, metrologist, management, customer/manufacturer).

Note: ISO/TR 14253‑6 does not prescribe how to quantify economic costs of decision outcomes - that remains a business/management responsibility.

Practical applications and users

This Technical Report is useful for:

Metrologists and calibration labs defining acceptance/rejection criteria for inspection equipment and gauging.
Quality engineers and production managers who need to balance measurement uncertainty, process capability and economic outcomes.
Designers and customers who must agree on the functional implications of tolerances and decision rules.
Suppliers and contract manufacturers implementing agreed inspection rules and documenting acceptance limits and guard bands.

Related standards

ISO 14253‑1: Decision rules (default)
ISO 14978: GPS measuring equipment
ISO 17450‑2: GPS basic tenets and uncertainties
ISO 21747: Process capability statistics
ISO/IEC Guide 98‑3 (GUM) and ISO/IEC Guide 99 (VIM)

ISO/TR 14253-6:2012 PDF

Technical details

Abstract

Overview

Key topics and requirements

Practical applications and users

Related standards

Related standards

Abstract

Overview

Key topics and requirements

Practical applications and users

Related standards

Related standards

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