SIST EN ISO 14253-2:2011

Geometrical product specifications (GPS) - Inspection by measurement of workpieces and measuring equipment - Part 2: Guidance for the estimation of uncertainty in GPS measurement, in calibration of measuring equipment and in product verification (ISO 14253-2:2011)

This Technical Specification gives guidance on the implementation of the concept of "Guide to the estimation of uncertainty in measurement" (in short GUM) to be applied in industry for the calibration of (measurement) standards and measuring equipment in the field of GPS and the measurement of workpiece GPS-characteristics.
The aim is to promote full information on how to achieve uncertainty statements and provide the basis for international comparison of results of measurements and their uncertainties (relationship between purchaser and supplier).
This Technical Specification is intended to support ISO 14253-1. This Technical Specification and ISO 14253-1 are beneficial to all technical functions in a company in the interpretation of GPS specifications (i.e. tolerances of workpiece characteristics and values of maximum permissible errors (MPE) for metrological characteristics of measuring equipment.

Geometrische Produktspezifikationen (GPS) - Prüfung von Werkstücken und Messgeräten durch Messungen - Teil 2: Leitfaden zur Schätzung der Unsicherheit von GPS-Messungen bei der Kalibrierung von Messgeräten und bei der Produktprüfung (ISO 14253-2:2011)

Diese Technische Spezifikation enthält Leitlinien für die Einführung des Konzepts des „Leitfadens zur Angabe der Unsicherheit beim Messen“ (abgekürzt GUM), welcher in der Industrie bei der Kalibrierung von Normalen und Messeinrichtungen im GPS-Bereich und bei der Messung von Werkstück-GPS-Merkmalen angewendet werden soll. Ziel ist es, eine vollständige Information darüber zu geben, wie die Angaben zur Unsicherheit ermittelt werden können, sowie die Schaffung einer Grundlage für den internationalen Vergleich von Mess¬ergebnissen und deren Unsicherheit (Beziehung zwischen Abnehmer und Hersteller).
Diese Technische Spezifikation soll ISO 14253-1 unterstützen und ist mit ISO 14253-1 für alle technischen Aufgaben in einem Unternehmen entsprechend der GPS-Spezifikationen (d. h. für Toleranzen der Merkmale von Werkstücken und den Werten der maximal zulässigen Abweichungen (MPE) für messtechnische Merk-male von Messeinrichtungen) nützlich.
Diese Technische Spezifikation führt eine Prozedur für das Unsicherheits-MAnagement — PUMA — ein. Es handelt sich um ein praktisches, iteratives, auf dem GUM basierendes Verfahren zur Schätzung der Unsicher¬heit ohne Änderung des Grundlagenkonzeptes von GUM und soll allgemein zur Schätzung der Messun¬sicherheit und zur Angabe der Unsicherheit in folgenden Teilen dienen:
-   Einzelmessergebnisse;
-   den Vergleich von zwei oder mehreren Messergebnissen;
-   den Vergleich von Messergebnissen — eines oder mehrerer Werkstücke oder Messeinrichtungen — mit gegebenen Spezifikationen (d. h. die maximal zulässigen Abweichungen (MPE) eines messtechnischen Merkmals eines Messgerätes oder eines Normals und die Toleranzgrenzen eines Werkstückmerkmals usw.), um Übereinstimmung oder Nichtübereinstimmung mit der Spezifikation festzustellen.

Spécification géométrique des produits (GPS) - Vérification par la mesure des pièces et des équipements de mesure - Partie 2: Lignes directrices pour l'estimation de l'incertitude dans les mesures GPS, dans l'étalonnage des équipements de mesure et dans la vérification des produits (ISO 14253-2:2011)

L'ISO 14253-2:2011 donne des lignes directrices pour la mise en ?uvre du concept de «Guide pour l'estimation de l'incertitude de mesure» (en abrégé GUM), à appliquer dans l'industrie pour l'étalonnage d'étalons et d'équipements de mesure dans le domaine GPS et la mesure des caractéristiques GPS de pièces. L'objectif est de présenter des informations complètes sur la façon d'obtenir les composantes d'incertitude et de fournir la base d'une comparaison internationale des résultats de mesure et de leurs incertitudes (relation entre le client et le fournisseur).
L'ISO 14253-2:2011 vient à l'appui de l'ISO 14253‑1. Ces deux parties sont bénéfiques à toutes les fonctions techniques d'une société dans l'interprétation des spécifications GPS [à savoir les tolérances des caractéristiques d'une pièce et les valeurs des erreurs maximales tolérées (MPE: Maximum Permissible Errors) pour les caractéristiques métrologiques de l'équipement de mesure].
L'ISO 14253-2:2011 introduit la procédure pour le management de l'incertitude (PUMA: Procedure for Uncertainty MAnagement), qui est une procédure pratique et itérative fondée sur le GUM pour estimer l'incertitude de mesure sans modifier les concepts de base du GUM. Elle est destinée à être utilisée d'une façon générale pour estimer l'incertitude de mesure et pour donner des composantes d'incertitude concernant des résultats de mesure unitaires; la comparaison de deux résultats de mesure ou plus; la comparaison de résultats de mesure à partir d'une ou de plusieurs pièces ou équipements de mesure avec des spécifications données [à savoir les erreurs maximales tolérées (MPE) pour une caractéristique métrologique d'un instrument de mesure ou un étalon, et les limites de tolérance pour une caractéristique de pièce, etc.] pour prouver la conformité ou la non-conformité aux spécifications.
La méthode itérative est fondamentalement basée sur une stratégie de limite supérieure, à savoir la surestimation de l'incertitude à tous les niveaux, mais les itérations déterminent la quantité de surestimation. Une surestimation intentionnelle, et non une sous-estimation, est nécessaire pour empêcher la prise de mauvaises décisions sur la base de résultats de mesure. La quantité de surestimation est contrôlée par l'évaluation économique de la situation.
La méthode itérative est un outil pour maximiser les profits et réduire les coûts des activités métrologiques d'une société. La méthode/procédure itérative est autorégulante sur le plan économique et est également un outil permettant de modifier/réduire l'incertitude de mesure existante avec pour but de réduire le coût de la métrologie (fabrication). La méthode itérative rend possible un compromis entre le risque, l'effort et le coût dans l'estimation et la budgétisation de l'incertitude.

Specifikacija geometrijskih veličin izdelka - Preskusi z merjenjem obdelovancev in merilne opreme - 2. del: Navodila za ugotavljanje negotovosti pri meritvi geometrijske veličine izdelka, pri umerjanju merilne opreme in pri preverjanju izdelka (ISO 14253-2:2011)

Ta tehnična specifikacija podaja navodila za izvajanje koncepta »Vodilo za ugotavljanje negotovosti pri merjenju« (skrajšano GUM) v industriji pri umerjanju (merilnih) standardov in merilne opreme pri specifikaciji geometrijskih veličin izdelka in merjenju karakteristik geometrijske veličine obdelovanca.
Cilj je spodbujati popolne informacije o tem, kako doseči izjave o negotovosti, in podati osnovo za mednarodno primerjavo rezultatov meritev in njihovih negotovostih (odnos med kupcem in dobaviteljem).
Ta tehnična specifikacija podpira ISO 14253-1. Ta tehnična specifikacija in ISO 14253-1 sta koristna za vse tehnične funkcije v podjetju pri razlagi specifikacij geometrijskih veličin izdelka (tj. tolerance značilnosti obdelovancev in vrednosti maksimalnih dovoljenih napak (MPE) za meroslovne karakteristike merilne opreme).

General Information

• Status: Published
• Public Enquiry End Date: 24-Jul-2009
• Publication Date: 10-Oct-2011
• ICS: 17.040.30 - Measuring instruments
• ICS: 17.040.40 - Geometrical Product Specification (GPS)
• Technical Committee: ISEL - Mechanical elements
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 20-Sep-2011
• Due Date: 25-Nov-2011
• Completion Date: 11-Oct-2011
• Ref Project: EN ISO 14253-2:2011 - Geometrical product specifications (GPS) - Inspection by measurement of workpieces and measuring equipment - Part 2: Guidance for the estimation of uncertainty in GPS measurement, in calibration of measuring equipment and in product verification (ISO 14253-2:2011)

Relations

• Replaces: SIST ENV ISO 14253-2:2002 - Geometrical Product Specifications (GPS) - Inspection by measurement of workpieces and measuring equipments - Part 2: Guide to the estimation of uncertainty in GPS measurement, in calibration of measuring equipment and in product verification (ISO/TS 14253-2:1999)
• Effective Date: 01-Nov-2011
• Corrected By: SIST EN ISO 14253-2:2011/AC:2014 - Geometrical product specifications (GPS) - Inspection by measurement of workpieces and measuring equipment - Part 2: Guidance for the estimation of uncertainty in GPS measurement, in calibration of measuring equipment and in product verification - Technical Corrigendum 1 (ISO 14253-2:2011/Cor 1:2013)
• Effective Date: 01-Jun-2014
• Replaces: SIST ISO/TS 14253-2:2002 - Geometrical Product Specifications (GPS) -- Inspection by measurement of workpieces and measuring equipment -- Part 2: Guide to the estimation of uncertainty in GPS measurement, in calibration of measuring equipment and in product verification
• Effective Date: 01-Nov-2011

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 14253-2:2011
01-november-2011
1DGRPHãþD
SIST ENV ISO 14253-2:2002
SIST ISO/TS 14253-2:2002
6SHFLILNDFLMDJHRPHWULMVNLKYHOLþLQL]GHOND3UHVNXVL]PHUMHQMHPREGHORYDQFHYLQ
PHULOQHRSUHPHGHO1DYRGLOD]DXJRWDYOMDQMHQHJRWRYRVWLSULPHULWYL
JHRPHWULMVNHYHOLþLQHL]GHONDSULXPHUMDQMXPHULOQHRSUHPHLQSULSUHYHUMDQMX
L]GHOND,62
Geometrical product specifications (GPS) - Inspection by measurement of workpieces
and measuring equipment - Part 2: Guidance for the estimation of uncertainty in GPS
measurement, in calibration of measuring equipment and in product verification (ISO
14253-2:2011)
Geometrische Produktspezifikationen (GPS) - Prüfung von Werkstücken und
Messgeräten durch Messungen - Teil 2: Leitfaden zur Schätzung der Unsicherheit von
GPS-Messungen bei der Kalibrierung von Messgeräten und bei der Produktprüfung (ISO
14253-2:2011)
Spécification géométrique des produits (GPS) - Vérification par la mesure des pièces et
des équipements de mesure - Partie 2: Lignes directrices pour l'estimation de
l'incertitude dans les mesures GPS, dans l'étalonnage des équipements de mesure et
dans la vérification des produits (ISO 14253-2:2011)
Ta slovenski standard je istoveten z: EN ISO 14253-2:2011
ICS:
17.040.30 Merila Measuring instruments
17.040.40 6SHFLILNDFLMDJHRPHWULMVNLK Geometrical Product
YHOLþLQL]GHOND*36 Specification (GPS)
SIST EN ISO 14253-2:2011 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 14253-2:2011

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SIST EN ISO 14253-2:2011


EUROPEAN STANDARD
EN ISO 14253-2

NORME EUROPÉENNE

EUROPÄISCHE NORM
April 2011
ICS 17.040.01 Supersedes ENV ISO 14253-2:2001
English Version
Geometrical product specifications (GPS) - Inspection by
measurement of workpieces and measuring equipment - Part 2:
Guidance for the estimation of uncertainty in GPS measurement,
in calibration of measuring equipment and in product verification
(ISO 14253-2:2011)
Spécification géométrique des produits (GPS) - Vérification Geometrische Produktspezifikationen (GPS) - Prüfung von
par la mesure des pièces et des équipements de mesure -
Werkstücken und Messgeräten durch Messen - Teil 2:
Partie 2: Lignes directrices pour l'estimation de l'incertitude Leitfaden zur Schätzung der Unsicherheit von GPS-
dans les mesures GPS, dans l'étalonnage des Messungen bei der Kalibrierung von Messgeräten und bei
équipements de mesure et dans la vérification des produits der Produktprüfung (ISO 14253-2:2011)
(ISO 14253-2:2011)
This European Standard was approved by CEN on 14 April 2011.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same
status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland,
Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.





EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2011 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 14253-2:2011: E
worldwide for CEN national Members.

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SIST EN ISO 14253-2:2011
EN ISO 14253-2:2011 (E)
Contents Page
Foreword .3

2

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SIST EN ISO 14253-2:2011
EN ISO 14253-2:2011 (E)
Foreword
This document (EN ISO 14253-2:2011) has been prepared by Technical Committee ISO/TC 213 "Dimensional
and geometrical product specifications and verification" in collaboration with Technical Committee
CEN/TC 290 “Dimensional and geometrical product specification and verification” the secretariat of which is
held by AFNOR.
This European Standard shall be given the status of a national standard, either by publication of an identical
text or by endorsement, at the latest by October 2011, and conflicting national standards shall be withdrawn at
the latest by October 2011.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
This document supersedes ENV ISO 14253-2:2001.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech
Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.
Endorsement notice
The text of ISO 14253-2:2011 has been approved by CEN as a EN ISO 14253-2:2011 without any
modification.

3

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SIST EN ISO 14253-2:2011

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SIST EN ISO 14253-2:2011

INTERNATIONAL ISO
STANDARD 14253-2
First edition
2011-04-15

Geometrical product specifications
(GPS) — Inspection by measurement of
workpieces and measuring equipment —
Part 2:
Guidance for the estimation
of uncertainty in GPS measurement,
in calibration of measuring equipment
and in product verification
Spécification géométrique des produits (GPS) — Vérification
par la mesure des pièces et des équipements de mesure —
Partie 2: Lignes directrices pour l'estimation de l'incertitude dans les
mesures GPS, dans l'étalonnage des équipements de mesure et dans
la vérification des produits




Reference number
ISO 14253-2:2011(E)
©
ISO 2011

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SIST EN ISO 14253-2:2011
ISO 14253-2:2011(E)

COPYRIGHT PROTECTED DOCUMENT


©  ISO 2011
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or
ISO's member body in the country of the requester.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail [e-mail]
Web www.iso.org
Published in Switzerland

ii © ISO 2011 – All rights reserved

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SIST EN ISO 14253-2:2011
ISO 14253-2:2011(E)
Contents Page
Foreword .v
Introduction.vi
1 Scope.1
2 Normative references.2
3 Terms and definitions .2
4 Symbols.4
5 Concept of the iterative GUM method for estimation of uncertainty of measurement .5
6 Procedure for Uncertainty MAnagement — PUMA .6
6.1 General .6
6.2 Uncertainty management for a given measurement process.6
6.3 Uncertainty management for design and development of a measurement
process/procedure .7
7 Sources of errors and uncertainty of measurement.10
7.1 Types of errors .10
7.2 Environment for the measurement.12
7.3 Reference element of measurement equipment .12
7.4 Measurement equipment .12
7.5 Measurement set-up (excluding the placement and clamping of the workpiece) .13
7.6 Software and calculations .13
7.7 Metrologist .13
7.8 Measurement object, workpiece or measuring instrument characteristic.13
7.9 Definition of the GPS characteristic, workpiece or measuring instrument characteristic.14
7.10 Measuring procedure.14
7.11 Physical constants and conversion factors .14
8 Tools for the estimation of uncertainty components, standard uncertainty and expanded
uncertainty .14
8.1 Estimation of uncertainty components.14
8.2 Type A evaluation for uncertainty components.15
8.3 Type B evaluation for uncertainty components.15
8.4 Common Type A and B evaluation examples.17
8.5 Black and transparent box model of uncertainty estimation.20
8.6 Black box method of uncertainty estimation — Summing of uncertainty components into
combined standard uncertainty, u .21
c
8.7 Transparent box method of uncertainty estimation — Summing of uncertainty
components into combined standard uncertainty, u .21
c
8.8 Evaluation of expanded uncertainty, U, from combined standard uncertainty, u .22
c
8.9 Nature of the uncertainty of measurement parameters u and U.22
c
9 Practical estimation of uncertainty — Uncertainty budgeting with PUMA.23
9.1 General .23
9.2 Preconditions for an uncertainty budget.23
9.3 Standard procedure for uncertainty budgeting .24
10 Applications .26
10.1 General .26
10.2 Documentation and evaluation of the uncertainty value .27
10.3 Design and documentation of the measurement or calibration procedure .27
10.4 Design, optimization and documentation of the calibration hierarchy .28
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SIST EN ISO 14253-2:2011
ISO 14253-2:2011(E)
10.5 Design and documentation of new measurement equipment . 29
10.6 Requirements for and qualification of the environment. 29
10.7 Requirements for and qualification of measurement personnel. 29
Annex A (informative) Example of uncertainty budgets — Calibration of a setting ring. 31
Annex B (informative) Example of uncertainty budgets — Design of a calibration hierarchy. 38
Annex C (informative) Example of uncertainty budgets — Measurement of roundness . 63
Annex D (informative) Relation to the GPS matrix model. 69
Bibliography. 71

iv © ISO 2011 – All rights reserved

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SIST EN ISO 14253-2:2011
ISO 14253-2:2011(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 14253-2 was prepared by Technical Committee ISO/TC 213, Dimensional and geometrical product
specifications and verification.
This first edition of ISO 14253-2 cancels and replaces ISO/TS 14253-2:1999, which has been technically
revised. It also incorporates the Technical Corrigendum ISO/TS 14253-2:1999/Cor.1:2007.
ISO 14253 consists of the following parts, under the general title Geometrical product specifications (GPS) —
Inspection by measurement of workpieces and measuring equipment:
⎯ Part 1: Decision rules for proving conformance or non-conformance with specifications
⎯ Part 2: Guidance for the estimation of uncertainty in GPS measurement, in calibration of measuring
equipment and in product verification
⎯ Part 3: Guidelines for achieving agreements on measurement uncertainty statements
⎯ Part 4: Background on functional limits and specification limits in decision rules [Technical Specification]
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SIST EN ISO 14253-2:2011
ISO 14253-2:2011(E)
Introduction
This part of ISO 14253 is a global GPS standard (see ISO/TR 14638:1995). This global GPS standard
influences chain links 4, 5 and 6 in all chains of standards.
The ISO/GPS Masterplan given in ISO/TR 14638 gives an overview of the ISO/GPS system of which this
document is a part. The fundamental rules of ISO/GPS given in ISO 8015 apply to this document and the
default decision rules given in ISO 14253-1 apply to specifications made in accordance with this document,
unless otherwise indicated.
For more detailed information on the relation of this International Standard to other standards and to the GPS
matrix model, see Annex D.
This part of ISO 14253 has been developed to support ISO 14253-1. This part of ISO 14253 establishes a
simplified, iterative procedure of the concept and the way to evaluate and determine uncertainty (standard
uncertainty and expanded uncertainty) of measurement, and the recommendations of the format to document
and report the uncertainty of measurement information as given in the Guide to the expression of uncertainty
in measurement (GUM). In most cases, only very limited resources are necessary to estimate uncertainty of
measurement by this simplified, iterative procedure, but the procedure may lead to a slight overestimation of
the uncertainty of measurement. If a more accurate estimation of the uncertainty of measurement is needed,
the more elaborated procedures of the GUM need to be applied.
This simplified, iterative procedure of the GUM methods is intended for GPS measurements, but may be used
in other areas of industrial (applied) metrology.
The uncertainty of measurement and the concept of handling uncertainty of measurement are important to all
the technical functions within a company. This part of ISO 14253 is relevant to several technical functions,
including management, design and development, manufacturing, quality assurance and metrology.
This part of ISO 14253 is of special importance in relation to ISO 9000 quality assurance systems, e.g. it is a
requirement that methods for monitoring and measurement of the quality management system processes are
suitable. The measurement uncertainty is a measure of the process suitability.
In this part of ISO 14253, the uncertainty of the result of a process of calibration and a process of
measurement is handled in the same way:
⎯ calibration is treated as a “measurement of the metrological characteristics of a measuring equipment or
a measurement standard”;
⎯ measurement is treated as a “measurement of the geometrical characteristics of a workpiece”.
Therefore, in most cases, no distinction is made in the text between measurement and calibration. The term
“measurement” is used as a synonym for both.

vi © ISO 2011 – All rights reserved

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SIST EN ISO 14253-2:2011
INTERNATIONAL STANDARD ISO 14253-2:2011(E)

Geometrical product specifications (GPS) — Inspection
by measurement of workpieces and measuring equipment —
Part 2:
Guidance for the estimation of uncertainty in GPS measurement,
in calibration of measuring equipment and in product
verification
1 Scope
This part of ISO 14253 gives guidance on the implementation of the concept of the “Guide to the estimation of
uncertainty in measurement” (in short GUM) to be applied in industry for the calibration of (measurement)
standards and measuring equipment in the field of GPS and the measurement of workpiece GPS
characteristics. The aim is to promote full information on how to achieve uncertainty statements and provide
the basis for international comparison of measurement results and their uncertainties (relationship between
purchaser and supplier).
This part of ISO 14253 is intended to support ISO 14253-1. Both parts are beneficial to all technical functions
in a company in the interpretation of GPS specifications [i.e. tolerances of workpiece characteristics and
values of maximum permissible errors (MPEs) for metrological characteristics of measuring equipment].
This part of ISO 14253 introduces the Procedure for Uncertainty MAnagement (PUMA), which is a practical,
iterative procedure based on the GUM for estimating uncertainty of measurement without changing the basic
concepts of the GUM. It is intended to be used generally for estimating uncertainty of measurement and giving
statements of uncertainty for:
⎯ single measurement results;
⎯ the comparison of two or more measurement results;
⎯ the comparison of measurement results — from one or more workpieces or pieces of measurement
equipment — with given specifications [i.e. maximum permissible errors (MPEs) for a metrological
characteristic of a measurement instrument or measurement standard, and tolerance limits for a
workpiece characteristic, etc.], for proving conformance or non-conformance with the specification.
The iterative method is based basically on an upper bound strategy, i.e. overestimation of the uncertainty at all
levels, but the iterations control the amount of overestimation. Intentional overestimation — and not under-
estimation — is necessary to prevent wrong decisions based on measurement results. The amount of
overestimation is controlled by economical evaluation of the situation.
The iterative method is a tool to maximize profit and minimize cost in the metrological activities of a company.
The iterative method/procedure is economically self-adjusting and is also a tool to change/reduce existing
uncertainty in measurement with the aim of reducing cost in metrology (manufacture). The iterative method
makes it possible to compromise between risk, effort and cost in uncertainty estimation and budgeting.
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SIST EN ISO 14253-2:2011
ISO 14253-2:2011(E)
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO 14253-1:1998, Geometrical Product Specifications (GPS) — Inspection by measurement of workpieces
and measuring equipment — Part 1: Decision rules for proving conformance or non-conformance with
specifications
ISO 14660-1:1999, Geometrical Product Specifications (GPS) — Geometrical features — Part 1: General
terms and definitions
ISO/IEC Guide 98-3:2008, Uncertainty of measurement — Part 3: Guide to the expression of uncertainty in
measurement (GUM:1995)
ISO/IEC Guide 99:2007, International vocabulary of metrology — Basic and general concepts and associated
terms (VIM)
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 14253-1, ISO 14660-1,
ISO/IEC Guide 98-3 and ISO/IEC Guide 99 and the following apply.
3.1
black box model for uncertainty estimation
model for uncertainty estimation in which the uncertainties associated with the relevant input quantities are
directly represented by their influence on the quantity value being attributed to a measurand (in the units of the
measurand)
NOTE 1 The “quantity value being attributed to a measurand” is typically a measured value.
NOTE 2 In many cases, a complex method of measurement may be looked upon as one simple black box with
stimulus in and result out from the black box. When a black box is opened, it may turn out to contain several “smaller”
black boxes or several transparent boxes, or both.
NOTE 3 The method of uncertainty estimation remains a black box method even if it is necessary to make
supplementary measurements to determine the values of influence quantities in order to make corresponding corrections.
3.2
transparent box model for uncertainty estimation
model for uncertainty estimation in which the relationship between the input quantities and the quantity value
being attributed to a measurand is explicitly expressed with equations or algorithms
3.3
measuring task
quantification of a measurand according to its definition
3.4
overall measurement task
measurement task that quantifies the final measurand
3.5
intermediate measurement task
measurement task obtained by subdividing the overall measurement task into simpler parts
NOTE 1 The subdivision of the overall measuring task serves the goal of simplification of the evaluation of uncertainty.
NOTE 2 The specific subdivisions are arbitrary, as is whether to subdivide at all.
2 © ISO 2011 – All rights reserved

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SIST EN ISO 14253-2:2011
ISO 14253-2:2011(E)
3.6
target uncertainty
U
T
〈for a measurement or calibration〉 uncertainty determined as the optimum for the measuring task
NOTE 1 Target uncertainty is the result of a management decision involving e.g. design, manufacturing, quality
assurance, service, marketing, sales and distribution.
NOTE 2 Target uncertainty is determined (optimized) taking into account the specification [tolerance or maximum
permissible error (MPE)], the process capability, cost, criticality and the requirements of ISO 9001, ISO 9004 and
ISO 14253-1.
NOTE 3 See also 8.8.
3.7
required uncertainty of measurement
U
R
uncertainty required for a given measurement process and task
NOTE See also 6.2. The required uncertainty may be specified by, for example, a customer.
3.8
uncertainty management
process of deriving an adequate measurement procedure from the measuring task and the target uncertainty
by using uncertainty budgeting techniques
3.9
uncertainty budget
〈for a measurement or calibration〉 statement summarizing the estimation of the uncertainty components that
contributes to the uncertainty of a result of a measurement
NOTE 1 The uncertainty of the result of the measurement is unambiguous only when the measurement procedure
(including the measurement object, measurand, measurement method and conditions) is defined.
NOTE 2 The term “budget” is used for the assignment of numerical values to the uncertainty components and their
combination and expansion, based on the measurement procedure, measurement conditions and assumptions.
3.10
uncertainty component
xx
source of uncertainty of measurement for a measuring process
3.11
limit value (variation limit) for an uncertainty component
a
xx
absolute value of the extreme value(s) of the uncertainty component, xx
3.12
uncertainty component
u
xx
standard uncertainty of the uncertainty component, xx
NOTE The iteration method uses the designation u for all uncertainty components.
xx
3.13
influence quantity of a measurement instrument
characteristic of a measuring instrument that affects the result of a measurement performed by the instrument
3.14
influence quantity of a workpiece
characteristic of a workpiece that affects the result of a measurement performed on that workpiece
© ISO 2011 – All rights reserved 3

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SIST EN ISO 14253-2:2011
ISO 14253-2:2011(E)
4 Symbols
For the purposes of this document, the generic symbols given in Table 1 apply.
Table 1 — Generic symbols
Symbol/
abbreviated Description
term
a limit value for a distribution
a limit value for an error or uncertainty component (in the unit of the measurement result, of the measurand)
xx
a* limit value for an error or uncertainty component (in the unit of the influence quantity)
xx
α linear coefficient of thermal expansion
b coefficient for transformation of a to u
xx xx
C correction (value)
d resolution of a measurement equipment
E Young's modulus
ER error (value of a measurement)
G function of several measurement values [G(X , X , . X , .)]
1 2 i
h hysteresis value
k coverage factor
m number of standard deviations in the half of a confidence interval
MR measurement result (value)
n number of .
N number of iterations
ν Poisson's number
p number of total uncorrelated uncertainty components
r number of total correlated uncertainty components
ρ correlation coefficient
t safety factor calculated based on the Student t distribution
TV true value of a measurement
u, u standard uncertainty (standard deviation)
i
s standard deviation of a sample
x
s standard deviation of a mean value of a sample
x
u combined standard uncertainty
c
u standard deviation of uncertainty component xx — uncertainty component
xx
U expanded uncertainty of measurement
U true uncertainty of measurement
A
U conventional true uncertainty of measurement
C
U approximated uncertainty of
...

SLOVENSKI STANDARD
oSIST prEN ISO 14253-2:2009
01-julij-2009
6SHFLILNDFLMDJHRPHWULMVNLKYHOLþLQL]GHOND3UHVNXVL]PHUMHQMHPREGHORYDQFHYLQ
PHULOQHRSUHPHGHO1DYRGLOD]DGRORþHYDQMHQHJRWRYRVWLSULPHULWYL
JHRPHWULMVNHYHOLþLQHL]GHONDSULNDOLEUDFLMLPHULOQHRSUHPHLQSULSUHYHUMDQMX
L]GHOND,62',6
Geometrical product specifications (GPS) - Inspection by measurement of workpieces
and measuring equipment - Part 2: Guidance for the estimation of uncertainty in GPS
measurement, in calibration of measuring equipment and in product verification (ISO/DIS
14253-2:2009)
Geometrische Produktspezifikationen (GPS) - Prüfung von Werkstücken und
Messgeräten durch Messungen - Teil 2: Leitfaden zur Schätzung der Unsicherheit von
GPS-Messungen bei der Kalibrierung von Messgeräten und bei der Produktprüfung
(ISO/DIS 14253-2:2009)
Spécification géométrique des produits (GPS) - Vérification par la mesure des pièces et
des équipements de mesure - Partie 2: Lignes directrices pour l'estimation de
l'incertitude dans les mesures GPS, dans l'étalonnage des équipements de mesure et
dans la vérification des produits (ISO/DIS 14253-2:2009)
Ta slovenski standard je istoveten z: prEN ISO 14253-2
ICS:
17.040.01 Linearne in kotne meritve na Linear and angular
splošno measurements in general
oSIST prEN ISO 14253-2:2009 en,fr
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN ISO 14253-2:2009

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oSIST prEN ISO 14253-2:2009
EUROPEAN STANDARD
DRAFT
prEN ISO 14253-2
NORME EUROPÉENNE
EUROPÄISCHE NORM
May 2009
ICS 17.040.01 Will supersede ENV ISO 14253-2:2001
English Version
Geometrical product specifications (GPS) - Inspection by
measurement of workpieces and measuring equipment - Part 2:
Guidance for the estimation of uncertainty in GPS measurement,
in calibration of measuring equipment and in product verification
(ISO/DIS 14253-2:2009)
Spécification géométrique des produits (GPS) - Vérification
par la mesure des pièces et des équipements de mesure -
Partie 2: Lignes directrices pour l'estimation de l'incertitude
dans les mesures GPS, dans l'étalonnage des
équipements de mesure et dans la vérification des produits
(ISO/DIS 14253-2:2009)
This draft European Standard is submitted to CEN members for parallel enquiry. It has been drawn up by the Technical Committee
CEN/TC 290.
If this draft becomes a European Standard, CEN members are bound to comply with the CEN/CENELEC Internal Regulations which
stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
This draft European Standard was established by CEN in three official versions (English, French, German). A version in any other language
made by translation under the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the
same status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are aware and to
provide supporting documentation.
Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without notice and
shall not be referred to as a European Standard.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2009 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN ISO 14253-2:2009: E
worldwide for CEN national Members.

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oSIST prEN ISO 14253-2:2009
prEN ISO 14253-2:2009 (E)
Contents Page
Foreword .3

2

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oSIST prEN ISO 14253-2:2009
prEN ISO 14253-2:2009 (E)
Foreword
This document (prEN ISO 14253-2:2009) has been prepared by Technical Committee ISO/TC 213
"Dimensional and geometrical product specifications and verification" in collaboration with Technical
Committee CEN/TC 290 “Dimensional and geometrical product specification and verification” the secretariat of
which is held by AFNOR.
This document is currently submitted to the parallel Enquiry.
This document will supersede ENV ISO 14253-2:2001.
Endorsement notice
The text of ISO/DIS 14253-2:2009 has been approved by CEN as a prEN ISO 14253-2:2009 without any
modification.

3

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oSIST prEN ISO 14253-2:2009

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oSIST prEN ISO 14253-2:2009
DRAFT INTERNATIONAL STANDARD ISO/DIS 14253-2
ISO/TC 213 Secretariat: DS
Voting begins on: Voting terminates on:
2009-05-14 2009-10-14
INTERNATIONAL ORGANIZATION FOR STANDARDIZATION • МЕЖДУНАРОДНАЯ ОРГАНИЗАЦИЯ ПО СТАНДАРТИЗАЦИИ • ORGANISATION INTERNATIONALE DE NORMALISATION
Geometrical product specifications (GPS) — Inspection by
measurement of workpieces and measuring equipment —
Part 2:
Guidance for the estimation of uncertainty in GPS measurement,
in calibration of measuring equipment and in product
verification
Spécification géométrique des produits (GPS) — Vérification par la mesure des pièces et des équipements de
mesure —
Partie 2: Lignes directrices pour l'estimation de l'incertitude dans les mesures GPS, dans l'étalonnage des
équipements de mesure et dans la vérification des produits
(Revision of ISO/TS 14253-2:1999 and ISO/TS 14253-2:1999/Cor 1:2007)
ICS 17.040.01

ISO/CEN PARALLEL PROCESSING
This draft has been developed within the International Organization for Standardization (ISO), and
processed under the ISO-lead mode of collaboration as defined in the Vienna Agreement.
This draft is hereby submitted to the ISO member bodies and to the CEN member bodies for a parallel
five-month enquiry.
Should this draft be accepted, a final draft, established on the basis of comments received, will be
submitted to a parallel two-month approval vote in ISO and formal vote in CEN.
To expedite distribution, this document is circulated as received from the committee secretariat.
ISO Central Secretariat work of editing and text composition will be undertaken at publication
stage.
Pour accélérer la distribution, le présent document est distribué tel qu'il est parvenu du
secrétariat du comité. Le travail de rédaction et de composition de texte sera effectué au
Secrétariat central de l'ISO au stade de publication.
THIS DOCUMENT IS A DRAFT CIRCULATED FOR COMMENT AND APPROVAL. IT IS THEREFORE SUBJECT TO CHANGE AND MAY NOT BE
REFERRED TO AS AN INTERNATIONAL STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS BEING ACCEPTABLE FOR INDUSTRIAL, TECHNOLOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
INTERNATIONAL STANDARDS MAY ON OCCASION HAVE TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN NATIONAL REGULATIONS.
RECIPIENTS OF THIS DRAFT ARE INVITED TO SUBMIT, WITH THEIR COMMENTS, NOTIFICATION OF ANY RELEVANT PATENT RIGHTS OF WHICH
THEY ARE AWARE AND TO PROVIDE SUPPORTING DOCUMENTATION.
©
International Organization for Standardization, 2009

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oSIST prEN ISO 14253-2:2009
ISO/DIS 14253-2
PDF disclaimer
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Violators may be prosecuted.
©
ii ISO 2009 – All rights reserved

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oSIST prEN ISO 14253-2:2009
ISO/DIS 14253-2:1999(E)
In accordance with ISO/TC 213 Resolution 823, the attached Technical Specification is being
submitted as a Draft International Standard in order to be converted into an International Standard.
To expedite circulation, the attached document contains the full text of the published Technical
Specification and the related Technical Corrigendum. The editing will be undertaken by the ISO
Central Secretariat at the publication stage.
© ISO 1999 – All rights reserved ii-2
DRAFT 2009

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oSIST prEN ISO 14253-2:2009

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oSIST prEN ISO 14253-2:2009
ISO/DIS 14253-2:1999(E)
Contents Page
Foreword.iv
Introduction.v
1 Scope .1
2 Normative references .2
3 Terms and definitions .2
4 Symbols .6
5 Concept of the iterative GUM-method for estimation of uncertainty of measurement .7
6 Procedure for Uncertainty MAnagement — PUMA .8
7 Sources of errors and uncertainty of measurement.13
8 Tools for the estimation of uncertainty components, standard uncertainty and expanded
uncertainty.17
9 Practical estimation of uncertainty — Uncertainty budgeting with PUMA.26
10 Applications .30
Annex A (informative) Example of uncertainty budgets — Calibration of a setting ring.34
Annex B (informative) Example of uncertainty budgets — Design of a calibration hierarchy.41
Annex C (informative) Example of uncertainty budgets — Measurement of roundness .65
Annex D (informative) Relation to the GPS matrix model.71
Bibliography.73
© ISO 1999 – All rights reserved iii
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oSIST prEN ISO 14253-2:2009
ISO/DIS 14253-2:1999(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO
member bodies). The work of preparing International Standards is normally carried out through ISO technical
committees. Each member body interested in a subject for which a technical committee has been established has
the right to be represented on that committee. International organizations, governmental and non-governmental, in
liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical
Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3.
The main task of technical committees is to prepare International Standards. Draft International Standards adopted
by the technical committees are circulated to the member bodies for voting. Publication as an International
Standard requires approval by at least 75 % of the member bodies casting a vote.
In other circumstances, particularly when there is an urgent market requirement for such documents, a technical
committee may decide to publish other types of normative document:
— an ISO Publicly Available Specification (ISO/PAS) represents an agreement between technical experts in an
ISO working group and is accepted for publication if it is approved by more than 50 % of the members of the
parent committee casting a vote;
— an ISO Technical Specification (ISO/TS) represents an agreement between the members of a technical
committee and is accepted for publication if it is approved by 2/3 of the members of the committee casting a
vote.
An ISO/PAS or ISO/TS is reviewed every three years with a view to deciding whether it can be transformed into an
International Standard.
Attention is drawn to the possibility that some of the elements of this Technical Specification may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO/TS 14253-2 was prepared by Technical Committee ISO/TC 213, Dimensional and geometrical product
specifications and verification.
ISO 14253 consists of the following parts, under the general title Geometrical product specifications (GPS) —
Inspection by measurement of workpieces and measuring equipment:
� Part 1: Decision rules for proving conformance or non-conformance with specification
� Part 2: Guide to the estimation of uncertainty in GPS measurement, in calibration of measuring equipment and
in product verification [Technical Specification]
� Part 3: Procedures for evaluating the integrity of uncertainty in measurement values
Annexes A to D of this Technical Specification are for information only.
iv © ISO 1999 – All rights reserved
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oSIST prEN ISO 14253-2:2009
ISO/DIS 14253-2:1999(E)
Introduction
This Technical Specification is a global GPS technical report (see ISO/TR 14638:1995). This global GPS Technical
Report influences chain link 4, 5 and 6 in all chains of standards.
For more detailed information of the relation of this report to other standards and the GPS matrix model, see
annex D.
This Technical Specification is developed to support ISO 14253-1. This Technical Specification establishes a
simplified, iterative procedure of the concept and the way to evaluate and determine uncertainty (standard
uncertainty and expanded uncertainty) of measurement, and the recommendations of the format to document and
report the uncertainty of measurement information as given in "Guide to the expression of uncertainty in
measurement" (GUM). In most cases only very limited resources are necessary to estimate uncertainty of
measurement by this simplified, iterative procedure, but the procedure may lead to a slight overestimation of the
uncertainty of measurement. If a more accurate estimation of the uncertainty of measurement is needed, the more
elaborated procedures of the GUM must be applied.
This simplified, iterative procedure of the GUM methods is intended for GPS measurements, but may be used in
other areas of industrial (applied) metrology.
Uncertainty of measurement and the concept of handling uncertainty of measurement being of importance to all the
technical functions in a company, this Technical Specification relates to e.g. management function, design and
development function, manufacture function, quality assurance function, metrology function, etc.
This Technical Specification is of special importance in relation to ISO 9000 quality assurance systems, where
it is a requirement that the uncertainty of measurement is known [e.g. 4.11.1, 4.11.2 a) and 4.11.2 b) of
ISO 9001:1994].
In this Technical Specification the uncertainty of the result of a process of calibration and a process of
measurement is handled in the same way:
� calibration is treated as "measurement of metrological characteristics of a measuring equipment or a
measurement standard";
� measurement is treated as "measurement of geometrical characteristics of a workpiece".
Therefore, in most cases no distinction is made in the text between measurement and calibration. The term
"measurement" is used as a synonym for both.
© ISO 1999 – All rights reserved v
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oSIST prEN ISO 14253-2:2009

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oSIST prEN ISO 14253-2:2009
DRAFT INTERNATIONAL STANDARD
ISO/DIS 14253-2:1999(E)
Geometrical product specifications (GPS) — Inspection by
measurement of workpieces and measuring equipment —
Part 2:
Guidance for the estimation of uncertainty in GPS measurement,
in calibration of measuring equipment and in product
verification
1 Scope
This Technical Specification gives guidance on the implementation of the concept of "Guide to the estimation of
uncertainty in measurement" (in short GUM) to be applied in industry for the calibration of (measurement)
standards and measuring equipment in the field of GPS and the measurement of workpiece GPS-characteristics.
The aim is to promote full information on how to achieve uncertainty statements and provide the basis for
international comparison of results of measurements and their uncertainties (relationship between purchaser and
supplier).
This Technical Specification is intended to support ISO 14253-1. This Technical Specification and ISO 14253-1 are
beneficial to all technical functions in a company in the interpretation of GPS specifications (i.e. tolerances of
workpiece characteristics and values of maximum permissible errors (MPE) for metrological characteristics of
measuring equipment).
This Technical Specification introduces the Procedure for Uncertainty MAnagement (PUMA), which is a practical,
iterative procedure based on the GUM for estimating uncertainty of measurement without changing the basic
concepts of the GUM and is intended to be used generally for estimating uncertainty of measurement and giving
statements of uncertainty for:
� single results of measurement;
� comparison of two or more results of measurement;
� comparison of results of measurement — from one or more workpieces or pieces of measurement equipment
— with given specifications [i.e. maximum permissible errors (MPE) for a metrological characteristic of a
measurement instrument or measurement standard, and tolerance limits for a workpiece characteristic, etc.],
for proving conformance or non-conformance with the specification.
The iterative method is based basically on an upper bound strategy, i.e. overestimation of the uncertainty at all
levels, but the iterations control the amount of overestimation. Intentional overestimation — and not under-
estimation — is necessary to prevent wrong decisions based on measurement results. The amount of
overestimation shall be controlled by economical evaluation of the situation.
The iterative method is a tool to maximize profit and minimize cost in the metrological activities of a company. The
iterative method/procedure is economically self-adjusting and is also a tool to change/reduce existing uncertainty in
measurement with the aim of reducing cost in metrology (manufacture). The iterative method makes it possible to
compromise between risk, effort and cost in uncertainty estimation and budgeting.
© ISO 1999 – All rights reserved 1
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oSIST prEN ISO 14253-2:2009
ISO/DIS 14253-2:1999(E)
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of
this Technical Specification. For dated references, subsequent amendments to, or revisions of, any of these
publications do not apply. However, parties to agreements based on this Technical Specification are encouraged to
investigate the possibility of applying the most recent editions of the normative documents indicated below. For
undated references, the latest edition of the normative document referred to applies. Members of ISO and IEC
maintain registers of currently valid International Standards.
ISO 1:1975, Standard reference temperature for industrial length measurements.
ISO 4288:1996, Geometrical Product Specifications (GPS) — Surface texture: Profile method — Rules and
procedures for the assessment of surface texture.
ISO 9001:1994, Quality systems — Model for quality systems in design, development, production, installation and
servicing.
ISO 9004-1:1994, Quality management and quality system elements — Part 1: Guidelines.
ISO 14253-1:1998, Geometrical Product Specification (GPS) — Inspection by measurement of workpieces and
measuring instruments — Part 1: Decision rules for proving conformance or non-conformance with specifications.
1)
ISO 14253-3:— , Geometrical Product Specification (GPS) — Inspection by measurement of workpieces and
measuring instruments — Part 3: Procedures for evaluating the integrity of uncertainty of measurement values.
ISO 14660-1:1999, Geometrical Product Specification (GPS) — Geometric features — Part 1: General terms and
definitions.
Guide to the expression of uncertainty in measurement (GUM).BIPM,IEC,IFCC,ISO,IUPAC,IUPAP,OIML,
1st edition, 1995.
International Vocabulary of Basic and General Terms in Metrology (VIM). BIPM, IEC, IFCC, ISO, IUPAC, IUPAP,
OIML, 2nd edition, 1993.
3 Terms and definitions
For the purposes of this Technical Specification, the terms and definitions given in ISO 14253-1, ISO 14660-1, VIM,
GUM and the following apply.
3.1
black box model for uncertainty estimation
method of/model for uncertainty estimation in which the output value of a measurement is obtained in the same unit
as the input (stimuli), rather than by measurement of other quantities functionally related to the measurand
NOTE 1 In the black box model — in this Technical Specification — the uncertainty components are assumed additive, the
influence quantities is transformed to the unit of the measurand and the sensitivity coefficients are equal to 1.
NOTE 2 In many cases a complex method of measurement may be looked upon as one simple black box with stimulus in
and result out from the black box. When a black box is opened, it may turn out to contain several "smaller" black boxes and/or
several transparent boxes.
NOTE 3 The method of uncertainty estimation remains a black box method even if it is necessary to make supplementary
measurements to determine the values of influence quantities in order to make corresponding corrections.
1) To be published.
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oSIST prEN ISO 14253-2:2009
ISO/DIS 14253-2:1999(E)
3.2
transparent box model for uncertainty estimation
method of/model for uncertainty estimation in which the value of a measurand is obtained by measurement of other
quantities functionally related to the measurand
3.3
measuring task
quantification of a measurand according to its definition
3.4
basic measurement task (basic measurement)
measurement task(s) which form the basis for evaluation of more complicated characteristics of a workpiece or a
measuring equipment
NOTE Examples of a basic measurement are:
a) one of several individual measurements of the deviation from straightness of a feature of a workpiece;
b) one of the individual measurements of error of indication of a micrometer when measuring the range of error of indication.
3.5
overall measurement task
complicated measuring task, which is evaluated on the basis of several and maybe different basic measurements
NOTE Examples of an overall measuring task are:
a) the measurement of straightness of a feature of a workpiece;
b) the range of error of indication of a micrometer.
3.6
expanded uncertainty (of a measurement)
U
[3.16 of ISO 14253-1:1998 and 2.3.5 of GUM:1995]
NOTE U (capital) always indicates expanded uncertainty of measurement.
3.7
true uncertainty
U
A
uncertainty of measurement that would be obtained by a perfect uncertainty estimation
NOTE 1 True uncertainties are by nature indeterminate.
NOTE 2 See also 8.8.
3.8
conventional true uncertainty — GUM uncertainty
U
c
uncertainty of measurement estimated completely according to the more elaborate procedures of GUM
NOTE 1 The conventional true uncertainty of measurement may differ from an uncertainty of measurement estimated
according to this Technical Specification.
NOTE 2 See also 8.8.
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oSIST prEN ISO 14253-2:2009
ISO/DIS 14253-2:1999(E)
3.9
approximated uncertainty
U
EN
uncertainty of measurement estimated by the simplified, iterative method
NOTE 1 The index N indicates that U is assessed by iteration number N. The designation U may be used without indication
EN E
of the iteration number, when it is without importance to know the number of iterations.
NOTE 2 See also 8.8.
3.10
target uncertainty (for a measurement or calibration)
U
T
uncertainty determined as the optimum for the measuring task
NOTE 1 Target uncertainty is the result of a management decision involving e.g. design, manufacturing, quality assurance,
service, marketing, sales and distribution.
NOTE 2 Target uncertainty is determined (optimized) taking into account the specification [tolerance or maximum
permissible error (MPE)], the process capability, cost, criticality and the requirements of 4.11.1, 4.11.2 of ISO 9001:1994, 13.1
of ISO 9004-1:1994 and ISO 14253-1.
NOTE 3 See also 8.8.
3.11
required uncertainty of measurement
U
R
uncertainty required for a given measurement process and task
NOTE See also 6.2. The required uncertainty may be specified by, for example, a customer.
3.12
uncertainty management
process of deriving an adequate measurement procedure from the measuring task and the target uncertainty by
using uncertainty budgeting techniques
3.13
uncertainty budget (for a measurement or calibration)
statement summarizing the estimation of the uncertainty components that contributes to the uncertainty of a result
of a measurement
NOTE 1 The uncertainty of the result of the measurement is unambiguous only when the measurement procedure (including
the measurement object, measurand, measurement method and conditions) is defined.
NOTE 2 The term "budget" is used for the assignment of numerical values to the uncertainty components, their combination
and expansion, based on the measurement procedure, measurement conditions and assumptions.
3.14
uncertainty contributor
xx
source of uncertainty of measurement for a measuring process
3.15
limit value (variation limit) for an uncertainty contributor
a
xx
absolute value of the extreme value(s) of the uncertainty contributor, xx
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oSIST prEN ISO 14253-2:2009
ISO/DIS 14253-2:1999(E)
3.16
uncertainty component
u
xx
standard uncertainty of the uncertainty contributor, xx
NOTE The iteration method uses the designation u for all uncertainty components. This is not consistent with the present
xx
version of GUM which sometimes uses the designation s for uncertainty components evaluated by A evaluation and the
xx
designation u for uncertainty components evaluated by B evaluation.
xx
3.17
influence quantity of a measurement instrument
characteristic of a measuring instrument that affects the result of a measurement performed by the instrument
3.18
influence quantity of a workpiece
characteristic of a workpiece that affects the result of a measurement performed on that workpiece
© ISO 1999 – All rights reserved 5
DRAFT 2009

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oSIST prEN ISO 14253-2:2009
ISO/DIS 14253-2:1999(E)
4
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