CLC IEC/TR 62461:2019

SLOVENSKI STANDARD
01-september-2019
Instrumenti za zaščito pred sevanjem - Določanje merilne negotovosti (IEC/TR
62461:2015)
Radiation protection instrumentation - Determination of uncertainty in measurement
(IEC/TR 62461:2015)
Strahlenschutz-Messgeräte - Bestimmung der Unsicherheit beim Messen (IEC/TR
62461:2015)
Instrumentation pour la radioprotection Détermination de l'incertitude de mesure
(IEC/TR 62461:2015)
Ta slovenski standard je istoveten z: CLC IEC/TR 62461:2019
ICS:
13.280 Varstvo pred sevanjem Radiation protection
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

TECHNICAL REPORT CLC IEC/TR 62461

RAPPORT TECHNIQUE
TECHNISCHER BERICHT
May 2019
ICS 13.280
English Version
Radiation protection instrumentation - Determination of
uncertainty in measurement
(IEC/TR 62461:2015)
Instrumentation pour la radioprotection - Détermination de Strahlenschutz-Messgeräte - Bestimmung der Unsicherheit
l'incertitude de mesure beim Messen
(IEC/TR 62461:2015) (IEC/TR 62461:2015)

This Technical Report was approved by CENELEC on 2019-05-20.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden,
Switzerland, Turkey and the United Kingdom.

European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2019 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. CLC IEC/TR 62461:2019 E

European foreword
This document (CLC IEC/TR 62461:2019) consists of the text of IEC/TR 62461:2015 prepared by
SC 45B "Radiation protection instrumentation" of IEC/TC 45 "Nuclear instrumentation".
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.

Endorsement notice
The text of the International Standard IEC/TR 62461:2015 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standards
indicated:
IEC 61526:2010 NOTE Harmonized as EN 61526:2013 (modified)
IEC 60846-1:2009 NOTE Harmonized as EN 60846-1:2014 (modified)
IEC 62387:2012 NOTE Harmonized as EN 62387:2016 (modified)
IEC 61005:2003 NOTE Harmonized as EN 61005:2004 (modified)
IEC 61577-2:2014 NOTE Harmonized as EN 61577-2:2017 (modified)
IEC 61577-3:2011 NOTE Harmonized as EN 61577-3:2014 (modified)
IEC 60325:2002 NOTE Harmonized as EN 60325:2004 (modified)

Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements 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.
NOTE 1  Where an International Publication has been modified by common modifications, indicated by (mod), the relevant
EN/HD applies.
NOTE 2  Up-to-date information on the latest versions of the European Standards listed in this annex is available here:
www.cenelec.eu.
Publication Year Title EN/HD Year
IEC 60050 series International Electrotechnical - -
Vocabulary General Index
ISO/IEC Guide 98-3 2008 Uncertainty of measurement - Part 3: - -
Guide to the expression of uncertainty in
measurement (GUM:1995)
ISO/IEC Guide 98-3 2008 Uncertainty of measurement – Part 3: - -
Supplement 1 Guide to the expression of uncertainty in
measurement (GUM:1995) -
Supplement 1: Propagation of
distributions using a Monte Carlo
method
IEC TR 62461 ®
Edition 2.0 2015-01
TECHNICAL
REPORT
colour
inside
Radiation protection instrumentation – Determination of uncertainty in

measurement
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 13.280 ISBN 978-2-8322-2216-4

– 2 – IEC TR 62461:2015 © IEC 2015
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 8
3 Terms and definitions . 9
4 List of symbols . 12
5 The GUM and the GUM S1 concept . 14
5.1 General concept of uncertainty determination . 14
5.1.1 Overview in four steps . 14
5.1.2 Summary of the analytical method for steps 3 and 4 . 15
5.1.3 Summary of the Monte Carlo method for steps 3 and 4 . 15
5.1.4 Which method to use: Analytical or Monte Carlo? . 16
5.2 Example of a model function . 16
5.3 Collection of data and existing knowledge for the example . 18
5.3.1 General . 18
5.3.2 Calibration factor for the example . 19
5.3.3 Zero reading for the example . 20
5.3.4 Reading for the example . 21
5.3.5 Relative response or correction factor for the example . 21
5.3.6 Comparison of probability density distributions for input quantities . 23
5.4 Calculation of the result of a measurement and its standard uncertainty
(uncertainty budget) . 25
5.4.1 General . 25
5.4.2 Analytical method . 25
5.4.3 Monte Carlo method . 26
5.4.4 Uncertainty budgets . 26
5.5 Statement of the measurement result and its expanded uncertainty . 27
5.5.1 General . 27
5.5.2 Analytical method . 28
5.5.3 Monte Carlo method . 28
5.5.4 Representation of the output distribution function in a simple form
(Monte Carlo method) . 31
6 Results below the decision threshold of the measuring device . 31
7 Overview of the annexes . 32
Annex A (informative) Example of an uncertainty analysis for a measurement with an
electronic ambient dose equivalent rate meter according to IEC 60846-1:2009 . 33
A.1 General . 33
A.2 Model function . 33
A.3 Calculation of the complete result of the measurement (measured value,
probability density distribution, associated standard uncertainty, and the
coverage interval) . 34
A.3.1 General . 34
A.3.2 Low level of consideration of measuring conditions . 35
A.3.3 High level of consideration of measuring conditions . 37
Annex B (informative) Example of an uncertainty analysis for a measurement with a
passive integrating dosimetry system according to IEC 62387:2012 . 40

IEC TR 62461:2015 © IEC 2015 – 3 –
B.1 General . 40
B.2 Model function . 40
B.3 Calculation of the complete result of the measurement (measured value,
probability density distribution, associated standard uncertainty, and the
coverage interval) . 41
B.3.1 General . 41
B.3.2 Low level of consideration of workplace conditions . 41
B.3.3 High level of consideration of workplace conditions . 43
Annex C (informative) Example of an uncertainty analysis for a measurement with an
electronic direct reading neutron ambient dose equivalent meter according to
IEC 61005:2003 . 46
C.1 General . 46
C.2 Model function . 46
C.3 Calculation of the complete result of the measurement (measured value,
probability density distribution, associated standard uncertainty, and the
coverage interval) . 47
C.3.1 General . 47
C.3.2 Analytical method . 47
C.3.3 Monte Carlo method . 48
C.3.4 Comparison of the result of the analytical and the Monte Carlo method . 49
Annex D (informative) Example of an uncertainty analysis for a calibration of radon
activity monitor according to the IEC 61577 series . 51
D.1 General . 51
D.2 Model function . 51
D.3 Calculation of the complete result of the measurement (measured value,
probability density distribution, associated standard uncertainty, and the
coverage interval) . 51
Annex E (informative) Example of an uncertainty analysis for a measurement of
surface emission rate with a contamination meter according to IEC 60325:2002 . 54
E.1 General . 54
E.2 Model function . 54
E.3 Calculation of the complete result of the measurement (measured value,
probability density distribution, associated standard uncertainty, and the
coverage interval) . 54
E.3.1 General . 54
E.3.2 Effects of distance . 55
E.3.3 Contamination non-uniformity . 55
E.3.4 Surface absorption . 56
E.3.5 Other influence quantities .
...