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)

Migrated from Progress Sheet (TC Comment) (2000-07-10): Will be a CR (BTS2 C 4/1996)

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/TS 14253-2:1999)

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 Messergebnissen 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 Merkmale 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 Unsicherheit ohne Änderung des Grundlagenkonzeptes von GUM und soll allgemein zur Schätzung der Messunsicherheit und zur Angabe der Unsicherheit in folgenden Teilen dienen:
3 Einzelmessergebnisse,
3 den Vergleich von zwei oder mehreren Messergebnissen,
3 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 pieces et des équipements de mesure - Guide pour l'estimation de l'incertitude de mesure dans l'étalonnage des équipements de mesure et dans la vérification des produits (ISO/TS 14253-2:1999)

Geometrical Product Specifications (GPS) - Inspection by measurement of workpieces and measuring equipments - Guide to the estimation of uncertainty in GPS measurement, in calibration of measuring equipment and in product verification (ISO/TS 14253-2:1999)

General Information

• Status: Withdrawn
• Publication Date: 31-Dec-2001
• Withdrawal Date: 20-Sep-2011
• ICS: 17.040.30 - Measuring instruments
• ICS: 17.040.40 - Geometrical Product Specification (GPS)
• Technical Committee: ISEL - Mechanical elements
• Current Stage: 9900 - Withdrawal (Adopted Project)
• Start Date: 20-Sep-2011
• Due Date: 13-Oct-2011
• Completion Date: 21-Sep-2011
• Ref Project: ENV ISO 14253-2:2001 - 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)

Relations

• Replaced By: 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)
• Effective Date: 01-Nov-2011

Standards Content (Sample)

SLOVENSKI STANDARD
SIST ENV ISO 14253-2:2002
01-januar-2002
Geometrical Product Specifications (GPS) - Inspection by measurement of
workpieces and measuring equipments - Guide to the estimation of uncertainty in
GPS measurement, in calibration of measuring equipment and in product
verification (ISO/TS 14253-2:1999)
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)
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/TS 14253-2:1999)
Spécification géométrique des produits (GPS) - Vérification par la mesure des pieces et
des équipements de mesure - Guide pour l'estimation de l'incertitude de mesure dans
l'étalonnage des équipements de mesure et dans la vérification des produits (ISO/TS
14253-2:1999)
Ta slovenski standard je istoveten z: ENV ISO 14253-2:2001
ICS:
17.040.01 Linearne in kotne meritve na Linear and angular
splošno measurements in general
SIST ENV ISO 14253-2:2002 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST ENV ISO 14253-2:2002

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SIST ENV ISO 14253-2:2002
ENV ISO 14253-2:2001 (E)
CORRECTED  2002-03-27
Foreword
The text of the Technical Specification from Technical Committee ISO/TC 213 "Dimensional and
geometrical product specifications and verification" of the International Organization for
Standardization (ISO) has been taken over as a European Prestandard by Technical Committee
CEN/TC 290 "Dimensional and geometrical product specification and verification", the
secretariat of which is held by AFNOR.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of
the following countries are bound to announce this European Prestandard: Austria, Belgium,
Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy,
Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United
Kingdom.
Endorsement notice
The text of the International Technical Specification ISO/TS 14253-2:1999 has been approved
by CEN as a European Prestandard without any modifications.
NOTE Normative references to International Standards are listed in annex ZA (normative).
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.
2

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SIST ENV ISO 14253-2:2002
ENV ISO 14253-2:2001 (E)
Annex ZA
(normative)
Normative references to international publications
with their relevant European publications
This European Standard incorporates by dated or undated reference, provisions from other
publications. These normative references are cited at the appropriate places in the text and the
publications are listed hereafter. For dated references, subsequent amendments to or revisions of
any of these publications apply to this European Standard only when incorporated in it by
amendment or revision. For undated references the latest edition of the publication referred to
applies (including amendments).
NOTE Where an International Publication has been modified by common modifications, indicated
by (mod.), the relevant EN/HD applies.
Publication Year Title EN Year
ISO 4288 1996 Geometrical product specifications EN ISO 4288 1997
(GPS) - Surface texture: Profile
method - Rules and procedures for
the assessment of surface texture
ISO 9001 2000 Quality management systems - EN ISO 9001 2000
Requirements
ISO 9004 2000 Quality management systems - EN ISO 9004 2000
Guidelines for performance
improvements
ISO 14253-1 1998 Geometrical Product Specifications EN ISO 14253-1 1998
(GPS) - Inspection by
measurement of workpieces and
measuring equipment - Part 1:
Decision rules for proving
conformance or non-conformance
with specifications
3

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SIST ENV ISO 14253-2:2002
TECHNICAL ISO/TS
SPECIFICATION 14253-2
First edition
1999-12-01
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
Spécification géométrique des produits (GPS) — Vérification par la mesure
des pièces et des équipements de mesure —
Partie 2: Guide 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/TS 14253-2:1999(E)
©
ISO 1999

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SIST ENV ISO 14253-2:2002
ISO/TS 14253-2:1999(E)
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ii © ISO 1999 – All rights reserved

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SIST ENV ISO 14253-2:2002
ISO/TS 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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SIST ENV ISO 14253-2:2002
ISO/TS 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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SIST ENV ISO 14253-2:2002
ISO/TS 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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SIST ENV ISO 14253-2:2002

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SIST ENV ISO 14253-2:2002
TECHNICAL SPECIFICATION ISO/TS 14253-2:1999(E)
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
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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SIST ENV ISO 14253-2:2002
ISO/TS 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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SIST ENV ISO 14253-2:2002
ISO/TS 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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SIST ENV ISO 14253-2:2002
ISO/TS 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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SIST ENV ISO 14253-2:2002
ISO/TS 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
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SIST ENV ISO 14253-2:2002
ISO/TS 14253-2:1999(E)
4 Symbols
For the purposes of this Technical Specification, the generic symbols given in Table 1 apply.
Table 1 — Generic symbols
Symbol Description
a
limit value for a distribution
a
limit value for an error or uncertainty contributor (in the unit of the result of measurement, of the measurand)
xx
a* limit value for an error or uncertainty contributor (in the unit of the influence quantity)
xx
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
Poisson's number
�
p number of total uncorrelated uncertainty contributors
r number of total correlated uncertainty contributors
correlation coefficient
�
TV true value of a measurement
u, u standard uncertainty (standard deviation)
i
s
standard deviation of a sample
x
s
x standard deviation of a mean value of a sample
u combined standard uncertainty
c
u standard deviation of uncertainty contributor 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 measurement (number of iteration not stated)
E
U approximated uncertainty of measurement of iteration number N
EN
U required uncertainty
R
U target uncertainty
T
U uncertainty value (not estimated according to GUM or this Technical Specification)
V
X measurement result (uncorrected)
X measurement result (in the transparent box model of uncertainty estimation)
i
Y measurement result (corrected)
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SIST ENV ISO 14253-2:2002
ISO/TS 14253-2:1999(E)
5 Concept of the iterative GUM-method for estimation of uncertainty of measurement
Applying the GUM method completely one will find a conventional true uncertainty of measurement, U .
C
The simplified, iterative method/procedure of this Technical Specification is to achieve estimated uncertainties of
measurements, U by overestimating the influencing uncertainty components/contributors (U W
...