SIST EN IEC 60544-5:2022
(Main)Electrical insulating materials - Determination of the effects of ionizing radiation - Part 5: Procedures for assessment of ageing in service (IEC 60544-5:2022)
Electrical insulating materials - Determination of the effects of ionizing radiation - Part 5: Procedures for assessment of ageing in service (IEC 60544-5:2022)
This part of IEC 60544 covers ageing assessment methods which can be applied to components based on polymeric materials (e.g. cable insulation and jackets, elastomeric seals, polymeric coatings, gaiters) which are used in environments where they are exposed to radiation.
The object of this standard is aimed at providing methods for the assessment of ageing in service. The approaches discussed in the following clauses cover ageing assessment programs based on condition monitoring (CM), the use of sample deposits in severe environments and sampling of real-time aged components.
Elektroisolierstoffe - Bestimmung der Wirkung ionisierender Strahlung - Teil 5: Bewertungsverfahren für die Alterung während des Einsatzes (IEC 60544-5:2022)
Matériaux isolants électriques - Détermination des effets des rayonnements ionisants - Partie 5: Procédures pour l'estimation du vieillissement en service (IEC 60544-5:2022)
IEC 60544-5:2022 est disponible sous forme de IEC 60544-5:2022 RLV qui contient la Norme internationale et sa version Redline, illustrant les modifications du contenu technique depuis l'édition précédente.
L'IEC 60544-5:2022 traite des méthodes d'évaluation du vieillissement qui peuvent être appliquées aux composants à base de matériaux polymères (gaines et isolations de câble, joints en élastomère, revêtements polymères, garnitures) qui sont utilisés dans des environnements où ils sont exposés aux rayonnements. L'objet du présent document est de fournir des méthodes pour évaluer le vieillissement en service des matériaux. Les approches examinées dans les Articles 5 à 9 concernent les programmes d'évaluation de vieillissement fondés sur une surveillance de l'état (CM, Condition Monitoring), l'utilisation de dépôts d'échantillons dans des environnements sévères et l'échantillonnage de composants vieillis en temps réel. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
- des références récentes ont été ajoutées en 7.4 afin d'introduire des méthodes de surveillance de l'état qui montrent des corrélations prometteuses vis-à-vis du vieillissement;
- les recommandations ont été mises à jour pour la mise en œuvre d'un dépôt d'échantillons en 9.2, l'installation d'un dépôt d'échantillons en 9.3 et les essais sur les échantillons du dépôt en 9.4;
- la liste de références a été mise à jour.
Električni izolacijski materiali - Ugotavljanje učinkov ionizirnega sevanja - 5. del: Postopki za ocenjevanje staranja med uporabo (IEC 60544-5:2022)
Ta del standarda IEC 60544 zajema metode za ocenjevanje staranja, ki jih je mogoče uporabiti za dele na osnovi polimernih materialov (npr. izolacija in plašči kablov, elastomerna tesnila, polimerne prevleke, gamaše), ki se uporabljajo v okoljih, kjer so izpostavljeni sevanju.
Namen tega standarda je zagotoviti metode za ocenjevanje staranja med uporabo. Pristopi, obravnavani v naslednjih točkah, zajemajo programe za ocenjevanje staranja na podlagi spremljanja stanja (CM), puščanja vzorcev v neugodnih okoljih in vzorčenja delov, staranih v realnem času.
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN IEC 60544-5:2022
01-oktober-2022
Nadomešča:
SIST EN 60544-5:2012
Električni izolacijski materiali - Ugotavljanje učinkov ionizirnega sevanja - 5. del:
Postopki za ocenjevanje staranja med uporabo (IEC 60544-5:2022)
Electrical insulating materials - Determination of the effects of ionizing radiation - Part 5:
Procedures for assessment of ageing in service (IEC 60544-5:2022)
Elektroisolierstoffe - Bestimmung der Wirkung ionisierender Strahlung - Teil 5:
Bewertungsverfahren für die Alterung während des Einsatzes (IEC 60544-5:2022)
Matériaux isolants électriques - Détermination des effets des rayonnements ionisants -
Partie 5: Procédures pour l'estimation du vieillissement en service (IEC 60544-5:2022)
Ta slovenski standard je istoveten z: EN IEC 60544-5:2022
ICS:
17.240 Merjenje sevanja Radiation measurements
29.035.01 Izolacijski materiali na Insulating materials in
splošno general
SIST EN IEC 60544-5:2022 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN IEC 60544-5:2022
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SIST EN IEC 60544-5:2022
EUROPEAN STANDARD EN IEC 60544-5
NORME EUROPÉENNE
EUROPÄISCHE NORM August 2022
ICS 17.240; 29.035.01 Supersedes EN 60544-5:2012
English Version
Electrical insulating materials - Determination of the effects of
ionizing radiation - Part 5: Procedures for assessment of ageing
in service
(IEC 60544-5:2022)
Matériaux isolants électriques - Détermination des effets Elektroisolierstoffe - Bestimmung der Wirkung ionisierender
des rayonnements ionisants - Partie 5: Procédures pour Strahlung - Teil 5: Bewertungsverfahren für die Alterung
l'évaluation du vieillissement en service während des Einsatzes
(IEC 60544-5:2022) (IEC 60544-5:2022)
This European Standard was approved by CENELEC on 2022-07-22. CENELEC 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 CENELEC 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 CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, 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
© 2022 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 60544-5:2022 E
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SIST EN IEC 60544-5:2022
EN IEC 60544-5:2022 (E)
European foreword
The text of document 112/523/CDV, future edition 3 of IEC 60544-5, prepared by IEC/TC 112
"Evaluation and qualification of electrical insulating materials and systems" was submitted to the IEC-
CENELEC parallel vote and approved by CENELEC as EN IEC 60544-5:2022.
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2023-04-22
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2025-07-22
document have to be withdrawn
This document supersedes EN 60544-5:2012 and all of its amendments and corrigenda (if any).
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.
Any feedback and questions on this document should be directed to the users’ national committee. A
complete listing of these bodies can be found on the CENELEC website.
Endorsement notice
The text of the International Standard IEC 60544-5:2022 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/IEEE 62582 (series) NOTE Harmonized as EN IEC/IEEE 62582 (series)
IEC 62465 NOTE Harmonized as EN IEC 62465
IEC/IEEE 60780-323 NOTE Harmonized as EN 60780-323
IEC 60544-4 NOTE Harmonized as EN 60544-4
IEC 60544-1 NOTE Harmonized as EN 60544-1
2
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EN IEC 60544-5:2022 (E)
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 60544-2 - Electrical insulating materials - EN 60544-2 -
Determination of the effects of ionizing
radiation on insulating materials - Part 2:
Procedures for irradiation and test
IEC/TS 61244-1 - Determination of long-term radiation - -
ageing in polymers - Part 1: Techniques for
monitoring diffusion-limited oxidation
IEC/TS 61244-2 - Determination of long-term radiation - -
ageing in polymers - Part 2: Procedures for
predicting ageing at low dose rates
3
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SIST EN IEC 60544-5:2022
IEC 60544-5
®
Edition 3.0 2022-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Electrical insulating materials – Determination of the effects of ionizing
radiation –
Part 5: Procedures for assessment of ageing in service
Matériaux isolants électriques – Détermination des effets des rayonnements
ionisants –
Partie 5: Procédures pour l'évaluation du vieillissement en service
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 17.240; 29.035.01 ISBN 978-2-8322-3826-4
Warning! Make sure that you obtained this publication from an authorized distributor.
Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.
® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
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CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms, definitions and abbreviated terms . 7
3.1 Terms and definitions . 7
3.2 Abbreviated terms . 7
4 Background . 8
4.1 General . 8
4.2 Diffusion-limited oxidation (DLO). 8
4.3 Dose rate effects (DRE) . 9
4.4 Accelerated radiation ageing . 9
4.5 Accelerated thermal ageing . 9
5 Approaches to ageing assessment . 10
6 Identifying components of concern . 10
6.1 General . 10
6.2 Priorities for ageing management . 10
6.3 Environmental monitoring . 10
6.4 Localized severe environments . 11
6.5 Worst case components . 11
7 Condition monitoring techniques . 11
7.1 General . 11
7.2 Establishing correlation curves for CM methods . 11
7.3 CM methods . 12
7.4 Using CM for short-term troubleshooting . 12
7.5 Using CM for long-term degradation assessment . 14
8 Predictive modelling . 15
9 Sample deposit . 16
9.1 General . 16
9.2 Requirements of a deposit . 16
9.3 Pre-ageing samples for a deposit . 16
9.4 Installation of a sample deposit . 17
9.5 Testing of samples from the deposit . 17
9.6 Determination of sampling intervals . 17
9.7 Real time aged materials . 18
Annex A (informative) Example of a CM correlation curve . 19
Annex B (informative) Use of a deposit . 20
B.1 Typical sample in a deposit . 20
B.2 Typical testing schedule for a deposit . 20
Bibliography . 21
Figure 1 – Development of ageing data on changes in tensile elongation and a
condition indicator (e.g. indenter modulus) – Schematic representation . 13
Figure 2 – Correlation curve derived from data in Figure 1 – Schematic representation . 14
Figure 3 – Estimation of elongation from a correlation curve . 15
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Figure 4 – Modification of sampling interval dependent on values of the CM indicator –
Schematic representation . 18
Figure A.1 – Correlation curve for indenter modulus against tensile elongation for a
CSPE cable jacket material [24] . 19
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INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTRICAL INSULATING MATERIALS –
DETERMINATION OF THE EFFECTS OF IONIZING RADIATION –
Part 5: Procedures for assessment of ageing in service
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international
co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and
in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,
Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their
preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
may participate in this preparatory work. International, governmental and non-governmental organizations liaising
with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for
Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence between
any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent
rights. IEC shall not be held responsible for identifying any or all such patent rights.
IEC 60544-5 has been prepared by IEC technical committee TC 112: Evaluation and
qualification of electrical insulating materials and systems. It is an International Standard.
This third edition cancels and replaces the second edition published in 2011. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) added recent references in 7.4 showing that some electrical condition monitoring methods
show promising correlations with ageing;
b) updated recommendations for implementation of a sample deposit in 9.2, installation of a
sample deposit in 9.3 and testing of samples from the deposit in 9.4;
c) updated list of references.
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SIST EN IEC 60544-5:2022
IEC 60544-5:2022 © IEC 2022 – 5 –
The text of this International Standard is based on the following documents:
Draft Report on voting
112/523/CDV 112/553/RVC
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/standardsdev/publications.
A list of all parts in the IEC 60544 series, published under the general title Electrical insulating
materials – Determination of the effects of ionizing radiation, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
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INTRODUCTION
Organic and polymeric materials provide a significant proportion of the insulation used in
electrical systems. These materials are sensitive to the effects of irradiation and the response
varies widely between different types. It is therefore important to be able to assess the degree
of degradation of these insulating materials during their service lifetimes. This part of IEC 60544
provides recommended procedures for assessing ageing of insulating materials in service.
There are a number of approaches to the assessment of ageing of polymer-based components
1
exposed to radiation environments [1], [2], [3], [4] . These are based on the better
understanding of the factors affecting ageing degradation which has been developed over
several decades. In nuclear power plants, qualification programmes are normally used for the
selection of components, including those based on polymeric materials. These initial
TM 2 TM 2
qualification procedures, such as IEEE Std 323 -1974 [5] and IEEE Std 383 -1974 [6],
were originally written before there was sufficient understanding of ageing mechanisms. Most
of the methods discussed in this document are therefore used to supplement the initial
qualification process.
This document is the fifth in a series dealing with the effect of ionizing radiation on insulating
materials.
IEC 60544-1 (Radiation interaction and dosimetry) constitutes an introduction dealing very
broadly with the problems involved in evaluating radiation effects. It also provides guidance on
dosimetry terminology, several methods of determining exposure and absorbed dose, and
methods of calculating absorbed dose in any specific material from the dosimetry method
applied.
IEC 60544-2 (Procedures for irradiation and test) describes procedures for maintaining seven
different types of exposure conditions during irradiation. It also specifies the controls that should
be maintained over these conditions so that when test results are reported, reliable comparisons
of material performance can be made. In addition, it defines certain important irradiation
conditions and test procedures to be used for property change determinations and
corresponding end-point criteria.
IEC 60544-3 has been withdrawn and incorporated into the second edition of IEC 60544-2.
IEC 60544-4 (Classification system for service in radiation environments) provides a
recommended classification system for categorizing the radiation endurance of insulation
materials.
___________
1
Numbers in square brackets refer to the Bibliography.
2
IEEE Std 323-1974 and IEEE Std 383-1974 are now withdrawn and have been superseded by more recent
revisions.
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IEC 60544-5:2022 © IEC 2022 – 7 –
ELECTRICAL INSULATING MATERIALS –
DETERMINATION OF THE EFFECTS OF IONIZING RADIATION –
Part 5: Procedures for assessment of ageing in service
1 Scope
This part of IEC 60544 covers ageing assessment methods which can be applied to components
based on polymeric materials (e.g. cable insulation and jackets, elastomeric seals, polymeric
coatings, gaiters) which are used in environments where they are exposed to radiation.
The object of this document is aimed at providing methods for the assessment of ageing in
service. The approaches discussed in Clause 5 through Clause 9 cover ageing assessment
programmes based on condition monitoring (CM), the use of sample deposits in severe
environments and sampling of real-time aged components.
2 Normative references
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.
IEC 60544-2, Electrical insulating materials – Determination of the effects of ionizing radiation
on insulating materials – Part 2: Procedures for irradiation and test
IEC TS 61244-1, Determination of long-term radiation ageing in polymers – Part 1: Techniques
for monitoring diffusion-limited oxidation
IEC TS 61244-2, Determination of long-term radiation ageing in polymers – Part 2: Procedures
for predicting ageing at low dose rates
3 Terms, definitions and abbreviated terms
3.1 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.2 Abbreviated terms
BWR boiling water reactor
CBQ condition-based qualification
CM condition monitoring
CSPE chlorosulphonated polyethylene
DBE design basis event
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DLO diffusion-limited oxidation
DRE dose rate effect
EPR ethylene propylene rubber
EQ environmental qualification
NPP nuclear power plant
OIT oxidation induction time
OITP oxidation induction temperature
PVC polyvinyl chloride
PWR pressurized water reactor
TGA thermo-gravimetric analysis
VVER water-cooled, water-moderated energy reactor (type of pressurized water reactor
developed by Russia)
XLPE cross-linked polyethylene
4 Background
4.1 General
There are a number of factors that need to be considered when assessing ageing of polymeric
components in radiation environments. In 4.2 through 4.5, some of these factors are briefly
discussed and references made to more detailed information.
To accelerate radiation-ageing environments, the normal approach is to increase the radiation
dose rate, often combined with an increase in temperature. The two most important potential
complications arising from such increases involve diffusion-limited oxidation (DLO), which is
described in 4.2, and chemical dose rate effects (DRE), which are described in 4.3. The
implications of these factors on the use and interpretation of condition monitoring (CM)
techniques are also discussed. Accelerated ageing programmes are briefly discussed in 4.4
and 4.5.
4.2 Diffusion-limited oxidation (DLO)
When polymers are exposed to an oxygen-containing environment (e.g. air), some oxygen will
be dissolved in the material. In the absence of oxygen-consuming reactions (oxidation), the
amount of dissolved oxygen will be proportional to the oxygen partial pressure surrounding the
polymer (well known from Henry’s Law). Ageing will lead to oxidation reactions in the polymer,
whose rate will increase significantly as the dose rate and temperature of ageing are increased.
If the rate of consumption of dissolved oxygen in the polymer is faster than the rate at which
oxygen can be replenished by diffusion from the surrounding atmosphere, the concentration of
dissolved oxygen in the interior regions will decrease with time (the oxygen concentration at
the sample surface will remain at its equilibrium value). The reduction in internal oxygen
concentration can lead to reduced or negligible oxidation, referred to as "diffusion-limited
oxidation".
The importance of this effect is dependent on the sample thickness (thinner samples giving
smaller DLO effects) and the ratio of the oxygen consumption rate to the oxygen permeability
coefficient P, which is the product of the oxygen diffusion and solubility parameters. Accelerated
radiation environments involve increases in dose rates, which increase the oxygen consumption
rate. If the temperature remains constant as the dose rate is increased, the oxygen permeability
coefficient will be unchanged. This means that DLO effects will become more important as the
dose rate is raised. For more detail about these effects, IEC TS 61244-1 shall be consulted.
The effects of DLO may also need to be considered when carrying out CM measurements. This
is not an issue for the many CM techniques which measure properties at ambient temperature,
such as those based on density and modulus measurements. On the other hand, several CM
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IEC 60544-5:2022 © IEC 2022 – 9 –
techniques such as oxidation induction time (OIT) and thermogravimetric analysis (TGA) use
quite elevated temperatures during the measurements. For these techniques, it is quite possible
to have DLO effects present during measurement of the CM parameter. For this reason, detailed
test methods for CM have been developed [8] to ensure that the sample preparation and test
procedure avoid DLO effects. DLO shall be addressed when developing correlation curves for
CM methods, to ensure that representative data are obtained for both radiation and thermal
ageing.
4.3 Dose rate effects (DRE)
The existence of radiation dose rate effects and methods for dealing with these effects are
described in IEC TS 61244-2. This standard shall be consulted for more detail about these
effects. Generally, DRE are separated into two types. The first type, which is commonly
observed in accelerated radiation-ageing experiments, is due to the DLO effects described in
4.2. These DLO-based effects represent a physical, geometry-dependent DRE.
The second type of interest to the current discussion concerns chemical DRE. Such chemically
based DRE are much less common. A documented case of chemical DRE is found in PVC and
low density polyethylene materials, caused by the slow breakdown of hydroperoxide
intermediate species in the oxidation reaction [9]. The existence of such chemical DRE shall be
checked at the start of any accelerated ageing programme. If there are no data available in the
literature for the specific materials of interest, this can be checked by including tests at low
dose rates in the ageing programme.
4.4 Accelerated radiation ageing
Accelerated ageing programmes in the laboratory tend to use acceleration factors much lower
than are normally used in equipment qualification. This may avoid some of the problems
associated with DLO and DRE. The ageing produced may then be a better simulation of the
long-term ageing that occurs under service conditions. The data that are obtained in accelerated
ageing tests can be used with predictive models to enable assessments to be made of the
behaviour of the materials under service conditions.
Accelerated ageing programmes require a matrix of test data to be generated over a range of
environmental conditions as described in IEC TS 61244-2. As a minimum, da
...
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