IEC/IEEE 62582-1:2024

IEC/IEEE 62582-1 ®
Edition 2.0 2024-09
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Nuclear power plants – Instrumentation and control important to safety –
Electrical equipment condition monitoring methods –
Part 1: General
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 being
secured. Requests for permission to reproduce should be addressed to either IEC at the address below or IEC’s
member National Committee in the country of the requester or from IEEE.

IEC Secretariat Institute of Electrical and Electronics Engineers, Inc.
3, rue de Varembé 3 Park Avenue
CH-1211 Geneva 20 New York, NY 10016-5997
Switzerland United States of America
Tel.: +41 22 919 02 11 stds.ipr@ieee.org
info@iec.ch www.ieee.org
www.iec.ch
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About the IEEE
IEEE is the world’s largest professional association dedicated to advancing technological innovation and excellence for the
benefit of humanity. IEEE and its members inspire a global community through its highly cited publications, conferences,
technology standards, and professional and educational activities.

About IEC/IEEE publications
The technical content of IEC/IEEE publications is kept under constant review by the IEC and IEEE. Please make sure that
you have the latest edition, a corrigendum or an amendment might have been published.

IEC publications search - webstore.iec.ch/advsearchform IEC Products & Services Portal - products.iec.ch
The advanced search enables to find IEC publications by a Discover our powerful search engine and read freely all the
variety of criteria (reference number, text, technical publications previews, graphical symbols and the glossary.
committee, …). It also gives information on projects, replaced With a subscription you will always have access to up to date
and withdrawn publications. content tailored to your needs.

IEC Just Published - webstore.iec.ch/justpublished
Electropedia - www.electropedia.org
Stay up to date on all new IEC publications. Just Published
The world's leading online dictionary on electrotechnology,
details all new publications released. Available online and once
containing more than 22 500 terminological entries in English
a month by email.
and French, with equivalent terms in 25 additional languages.

Also known as the International Electrotechnical Vocabulary
IEC Customer Service Centre - webstore.iec.ch/csc
(IEV) online.
If you wish to give us your feedback on this publication or need

further assistance, please contact the Customer Service
Centre: sales@iec.ch.
IEC/IEEE 62582-1 ®
Edition 2.0 2024-09
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Nuclear power plants – Instrumentation and control important to safety –
Electrical equipment condition monitoring methods –
Part 1: General
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 27.120.20 ISBN 978-2-8322-9819-0

– 2 – IEC/IEEE 62582-1:2024 RLV
© IEC/IEEE 2024
CONTENTS
FOREWORD . 3
INTRODUCTION . 2
1 Scope and object . 9
2 Normative references . 9
3 Terms and definitions . 9
4 Condition indicators . 10
4.1 General . 12
4.2 Chemical indicators . 13
4.3 Physical indicators . 13
4.4 Electrical indicators . 13
4.5 MiscellaneousOther indicators . 13
4.6 Visual and tactile observation . 13
5 Applicability of condition indicators to different types of organic polymeric
materials . 14
6 Destructive and non-destructive condition monitoring . 14
7 Application of condition monitoring in equipment qualification and management of
ageing . 14
7.1 General . 14
7.2 Use of condition monitoring in the establishment of qualified life . 15
7.2.1 Establishment of qualified life . 15
7.2.2 Determination of the acceleration factor in accelerated thermal ageing . 15
7.3 Use of condition monitoring in the extension of qualified life . 17
7.4 Use of condition monitoring in the establishment and assessment of
qualified condition . 17
7.5 Use of baseline data . 18
Annex A (informative) Diffusion limited oxidation (DLO) . 19
A.1 General . 19
A.2 Importance of DLO in thermal ageing . 19
A.3 Methods for profiling DLO effects . 20
A.4 Theoretical approach to DLO . 20
Bibliography . 22

Figure 1 – Example of an Arrhenius diagram . 16
Figure 2 – Influence of activation energy on qualified life, determined from artificial
accelerated thermal ageing for 42 days at 110 °C, followed by a simulated design
basis event . 16
Figure 3 – Illustration of the principle of condition-based qualification . 18
Figure A.1 – Indenter modulus profiles for EPDM seal aged at 170 °C (left) and
110 °C (right) [1] . 20

© IEC/IEEE 2024
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
NUCLEAR POWER PLANTS –
INSTRUMENTATION AND CONTROL IMPORTANT TO SAFETY –
ELECTRICAL EQUIPMENT CONDITION MONITORING METHODS –

Part 1: General
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 document(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.
IEEE Standards documents are developed within IEEE Societies and Standards Coordinating Committees of the
IEEE Standards Association (IEEE SA) Standards Board. IEEE develops its standards through a consensus
development process, approved by the American National Standards Institute, which brings together volunteers
representing varied viewpoints and interests to achieve the final product. Volunteers are not necessarily members
of IEEE and serve without compensation. While IEEE administers the process and establishes rules to promote
fairness in the consensus development process, IEEE does not independently evaluate, test, or verify the
accuracy of any of the information contained in its standards. Use of IEEE Standards documents is wholly
voluntary. IEEE documents are made available for use subject to important notices and legal disclaimers (see
https://standards.ieee.org/ipr/disclaimers.html for more information).
IEC collaborates closely with IEEE in accordance with conditions determined by agreement between the two
organizations. This Dual Logo International Standard was jointly developed by the IEC and IEEE under the terms
of that agreement.
2) The formal decisions 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. The formal decisions of IEEE on technical matters, once consensus within IEEE Societies
and Standards Coordinating Committees has been reached, is determined by a balanced ballot of materially
interested parties who indicate interest in reviewing the proposed standard. Final approval of the IEEE standards
document is given by the IEEE Standards Association (IEEE SA) Standards Board.
3) IEC/IEEE Publications have the form of recommendations for international use and are accepted by IEC National
Committees/IEEE Societies in that sense. While all reasonable efforts are made to ensure that the technical
content of IEC/IEEE Publications is accurate, IEC or IEEE 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
(including IEC/IEEE Publications) transparently to the maximum extent possible in their national and regional
publications. Any divergence between any IEC/IEEE Publication and the corresponding national or regional
publication shall be clearly indicated in the latter.
5) IEC and IEEE do not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC and IEEE are 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 IEEE or their directors, employees, servants or agents including individual
experts and members of technical committees and IEC National Committees, or volunteers of IEEE Societies and
the Standards Coordinating Committees of the IEEE Standards Association (IEEE SA) Standards Board, 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/IEEE
Publication or any other IEC or IEEE 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.

– 4 – IEC/IEEE 62582-1:2024 RLV
© IEC/IEEE 2024
9) Attention is drawn to the possibility that implementation of this IEC/IEEE Publication may require use of material
covered by patent rights. By publication of this standard, no position is taken with respect to the existence or
validity of any patent rights in connection therewith. IEC or IEEE shall not be held responsible for identifying
Essential Patent Claims for which a license may be required, for conducting inquiries into the legal validity or
scope of Patent Claims or determining whether any licensing terms or conditions provided in connection with
submission of a Letter of Assurance, if any, or in any licensing agreements are reasonable or non-discriminatory.
Users of this standard are expressly advised that determination of the validity of any patent rights, and the risk
of infringement of such rights, is entirely their own responsibility.
This redline version of the official IEC Standard allows the user to identify the changes
made to the previous edition IEC/IEEE 62582-1:2011. A vertical bar appears in the margin
wherever a change has been made. Additions are in green text, deletions are in
strikethrough red text.
© IEC/IEEE 2024
IEC/IEEE 62582-1 was prepared by subcommittee 45A: Instrumentation and control of nuclear
facilities, of IEC technical committee 45: Nuclear instrumentation, in cooperation with Nuclear
Power Engineering Committee of the IEEE Power & Energy Society , under the IEC/IEEE Dual
Logo Agreement between IEC and IEEE. It is an International Standard.
This document is published as an IEC/IEEE Dual Logo standard.
This second edition cancels and replaces the first 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) Integration of experience from the work with IAEA-TECDOC-1825:2017 “Benchmark
analysis for condition monitoring test techniques of low voltage cables in nuclear power
plants. Final results of a Coordinated Research Project”.
b) Referral to IEC/IEEE 60780-323 instead of IEC 60780 and IEEE 323.
The text of this International Standard is based on the following IEC documents:
Draft Report on voting
45A/1510/CDV 45A/1537/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 the rules given in the ISO/IEC Directives, Part 2,
available at www.iec.ch/members_experts/refdocs. The main document types developed by IEC
are described in greater detail at www.iec.ch/publications/.
A list of all parts of IEC/IEEE 62582 series, under the general title Nuclear power plants –
Instrumentation and control important to safety – Electrical equipment condition monitoring
methods, can be found on the IEC website.
The IEC Technical Committee and IEEE Technical Committee have 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, or
• revised.
IMPORTANT – The "colour inside" logo on the cover page of this document indicates
that it contains colours which are considered to be useful for the correct understanding
of its contents. Users should therefore print this document using a colour printer.

___________
A list of IEEE participants can be found at the following URL: http://standards.ieee.org/downloads/62582-1/62582-
1-2011/62582-1-2011_wg-participants.pdf.

– 6 – IEC/IEEE 62582-1:2024 RLV
© IEC/IEEE 2024
INTRODUCTION
a) Technical background, main issues and organisation of this document
This part of this IEC/IEEE 62582 series focuses on methods for condition monitoring for
management of ageing of electrical equipment installed in nuclear power plants and for
application of the concept of qualified condition.
IEC/IEEE 6258-1 is the first part of the IEC/IEEE 62582 series of standards, containing
background and guidelines for the application of methods for condition monitoring of electrical
equipment important to safety of nuclear power plants. The detailed descriptions of the methods
are given in the other parts, one part for each method. This document also includes some
elements which are common to all methods.
IEC/IEEE 62582 series is issued with a joint logo which makes it applicable to the management
of ageing of electrical equipment qualified to IEEE as well as IEC Standards.
Condition monitoring is a developing field and more methods will be added to the
IEC/IEEE 62582 series when they are considered widely applied and a good reproducibility of
the condition monitoring method can be demonstrated.
Historically, IEEE Std 323-2003 introduced the concept and role that conditionbased
qualification could be used in equipment qualification as an adjunct to qualified life. In
equipment qualification, the condition of the equipment for which acceptable performance was
demonstrated is the qualified condition. The qualified condition is the condition of equipment,
prior to the start of a design basis event, for which the equipment was demonstrated to meet
the design requirements for the specified service conditions.
IEC/IEEE 60780-323 defined condition-based qualification which is an adjunct to type testing.
The qualified condition is established by condition indicator(s) prior to the start of accident
conditions for which the equipment was demonstrated to meet the design requirements for the
specified service conditions. IEC/IEEE 60780-323 defined condition indicator.
Significant research has been performed on condition monitoring techniques and the use of
these techniques in equipment qualification as noted in NUREG/CR-6704, Vol. 2
(BNL -NUREG-52610) [1], JNES-SS-0903, 2009 [2] and IAEA-TECDOC-1825:2017 [3].
It is intended that this IEC/IEEE document be used by operators of nuclear power plants,
systems evaluators and by licensors.
b) Situation of the current standard in the structure of the IEC SC 45A standard series
IEC/IEEE 62582-1 is the third level IEC SC 45A document tackling the issue of application of
condition monitoring in equipment qualification and management of ageing of electrical I&C
equipment in nuclear power plants.
IEC/IEEE 62582-1 is to be read in association with IEC/IEEE 60780-323, which provides
general requirements for qualification of I&C systems and equipment that are used to perform
functions important to safety in NPPs and nuclear facilities.
For more details on the structure of the IEC SC 45A standard series, see item d) of this
introduction.
___________
Numbers in square brackets refer to the Bibliography.

© IEC/IEEE 2024
c) Recommendations and limitations regarding the application of this document
It is important to note that this document establishes no additional functional requirements for
safety systems.
This document discusses the general measurement technique for current condition monitoring
methods and is not meant to cover any specific technologies.
d) Description of the structure of the IEC SC 45A standard series and relationships with
other IEC documents and other bodies documents (IAEA, ISO)
The top-level document of the IEC SC 45A standard series is IEC 61513. It provides general
requirements for I&C systems and equipment that are used to perform functions important to
safety in NPPs. IEC 61513 structures the IEC SC 45A standard series.
IEC 61513 refers directly to other IEC SC 45A standards for general topics related to
categorization of functions and classification of systems, qualification, separation of systems,
defence against common cause failure, software aspects of computer-based systems, hardware
aspects of computer-based systems, and control room design. The standards referenced
directly at this second level should be considered together with IEC 61513 as a consistent
document set.
The IEC SC 45A standard series comprises a hierarchy of four levels. The top-level documents
of the IEC SC 45A standard series are IEC 61513 and IEC 63046.
IEC 61513 provides general requirements for instrumentation and control (I&C) systems and
equipment that are used to perform functions important to safety in nuclear power plants
(NPPs). IEC 63046 provides general requirements for electrical power systems of NPPs; it
covers power supply systems including the supply systems of the I&C systems.
IEC 61513 and IEC 63046 are to be considered in conjunction and at the same level. IEC 61513
and IEC 63046 structure the IEC SC 45A standard series and shape a complete framework
establishing general requirements for instrumentation, control and electrical power systems for
nuclear power plants.
IEC 61513 and IEC 63046 refer directly to other IEC SC 45A standards for general
requirements for specific topics, such as categorization of functions and classification of
systems, qualification, separation, defence against common cause failure, control room design,
electromagnetic compatibility, human factors engineering, cybersecurity, software and
hardware aspects for programmable digital systems, coordination of safety and security
requirements and management of ageing. The standards referenced directly at this second level
should be considered together with IEC 61513 and IEC 63046 as a consistent document set.
At a third level, IEC SC 45A standards not directly referenced by IEC 61513 or by IEC 63046
are standards related to specific requirements for specific equipment, technical methods, or
specific activities. Usually these documents, which make reference to second-level documents
for general topics requirements, can be used on their own.
A fourth level extending the IEC SC 45 standard series, corresponds to the Technical Reports
which are not normative.
IEC 61513 has adopted a presentation format similar to the basic safety publication IEC 61508
with an overall safety life-cycle framework and a system life-cycle framework and provides an
interpretation of the general requirements of IEC 61508-1, IEC 61508-2 and IEC 61508-4, for
the nuclear application sector. Compliance with IEC 61513 will facilitate consistency with the
requirements of IEC 61508 as they have been interpreted for the nuclear industry. In this
framework IEC 60880 and IEC 62138 correspond to IEC 61508-3 for the nuclear application
sector.
– 8 – IEC/IEEE 62582-1:2024 RLV
© IEC/IEEE 2024
IEC 61513 refers to ISO as well as to IAEA 50-C-QA (now replaced by IAEA GS-R-3) for topics
related to quality assurance (QA).
The IEC SC 45A standards series consistently implements and details the principles and basic
safety aspects provided in the IAEA code on the safety of NPPs and in the IAEA safety series,
in particular the Requirements NS-R-1, establishing safety requirements related to the design
of Nuclear Power Plants, and the Safety Guide NS-G-1.3 dealing with instrumentation and
control systems important to safety in Nuclear Power Plants. The terminology and definitions
used by SC 45A standards are consistent with those used by the IAEA.
The IEC SC 45A standards series consistently implements and details the safety and security
principles and basic aspects provided in the relevant IAEA safety standards and in the relevant
documents of the IAEA nuclear security series (NSS). In particular this includes the IAEA
requirements SSR-2/1 , establishing safety requirements related to the design of nuclear power
plants (NPPs), the IAEA safety guide SSG-30 dealing with the safety classification of structures,
systems and components in NPPs, the IAEA safety guide SSG-39 dealing with the design of
instrumentation and control systems for NPPs, the IAEA safety guide SSG-34 dealing with the
design of electrical power systems for NPPs, the IAEA safety guide SSG-51 dealing with human
factors engineering in the design of NPPs and the implementing guide NSS42-G for computer
security at nuclear facilities. The safety and security terminology and definitions used by the
SC 45A standards are consistent with those used by the IAEA.
IEC 61513 and IEC 63046 have adopted a presentation format similar to the basic safety
publication IEC 61508 with an overall life-cycle framework and a system life-cycle framework.
Regarding nuclear safety, IEC 61513 and IEC 63046 provide the interpretation of the general
requirements of IEC 61508-1, IEC 61508-2 and IEC 61508-4, for the nuclear application sector.
In this framework, IEC 60880, IEC 62138 and IEC 62566 correspond to IEC 61508-3 for the
nuclear application sector.
IEC 61513 and IEC 63046 refer to ISO 9001 as well as to IAEA GSR part 2 and IAEA GS-G-3.1
and IAEA GS-G-3.5 for topics related to quality assurance (QA).
At level 2, regarding nuclear security, IEC 62645 is the entry document for the IEC/SC 45A
security standards. It builds upon the valid high level principles and main concepts of the
generic security standards, in particular ISO/IEC 27001 and ISO/IEC 27002; it adapts them and
completes them to fit the nuclear context and coordinates with the IEC 62443 series. At level 2,
IEC 60964 is the entry document for the IEC SC 45A control rooms standards, IEC 63351 is the
entry document for the human factors engineering standards and IEC 62342 is the entry
document for the ageing management standards.
NOTE 1 It is assumed that for the design of I&C systems in NPPs that implement conventional safety functions (e.g.
to address worker safety, asset protection, chemical hazards, process energy hazards) international or national
standards would be applied.
NOTE 2 IEC TR 63400 provides a more comprehensive description of the overall structure of the IEC SC 45A
standards series and of its relationship with other standards bodies and standards.

© IEC/IEEE 2024
NUCLEAR POWER PLANTS –
INSTRUMENTATION AND CONTROL IMPORTANT TO SAFETY –
ELECTRICAL EQUIPMENT CONDITION MONITORING METHODS –

Part 1: General
1 Scope and object
This part of the IEC/IEEE 62582 series contains requirements for application of the other parts
of IEC/IEEE 62582 related to specific methods for condition monitoring in electrical equipment
important to safety of nuclear power plants. It also includes requirements which are common to
all methods. The procedures defined in IEC/IEEE 62582 are intended for detailed condition
monitoring.
IEC/IEEE 62582 specifies condition monitoring methods in sufficient detail to enhance the
accuracy and repeatability, and provide standard formats for reporting the results. The methods
specified are applicable to electrical equipment containing organic or polymeric materials. Some
methods are especially designed for the measurement of condition of a limited range of
equipment whilst others can be applied to all types of equipment for which the organic polymeric
parts are accessible.
Although the scope of IEC/IEEE 62582 is limited to the application of instrumentation and
control systems important to safety, the condition monitoring methods may can also be
applicable to other components which include organic or polymeric materials.
The different parts of IEC/IEEE 62582 are measurement standards, primarily for use in the
management of ageing in initial qualification and after installation. For the technical background
of condition monitoring methods, reference is made to other IEC standards, e.g.
IEC 60544-5 [1]. Information on the role of condition monitoring in qualification of electrical
equipment important to safety is found in IEC/IEEE Std 60780-323. General information on
management of ageing can be found in IEC 62342 [5] and IEEE 1205 [6].
NOTE The procedures defined in the IEC/IEEE 62582 are intended for detailed condition monitoring. A simplified
version of the procedures may can be appropriate for preliminary assessment of the need for detailed measurements.
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.
IEEE Std 323:2003, IEEE Standard for Qualifying Class 1E Equipment for Nuclear Power
Generating Stations
IEC/IEEE 60780-323, Nuclear facilities – Electrical equipment important to safety –
Qualification
IEC/IEEE 62582 (all parts), Nuclear power plants – Instrumentation and control important to
safety – Electrical equipment condition monitoring methods

– 10 – IEC/IEEE 62582-1:2024 RLV
© IEC/IEEE 2024
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
• IEC Electropedia: available at https://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp
• IEEE Standards Dictionary Online: available at http://dictionary.ieee.org
3.1
condition indicator
characteristic of a structure, system or component that can be observed, measured or trended
to infer or directly indicate the current and future ability of the structure, system or component
to function within acceptance criteria
[SOURCE: IAEA Nuclear Safety and Security Glossary, 20072022 (Interim) Edition]
3.2
condition monitoring
continuous or periodic tests, inspections, measurement or trending of the performance or
physical characteristics of structures, systems and components to indicate current or future
performance and the potential for failure
[SOURCE: IAEA Safety Glossary, 20072018 Edition, modified – note removed.]
3.3
equipment qualification
generation and maintenance of evidence to ensure that equipment will operate on demand,
under specified service conditions, to meet system performance requirements
[SOURCE: IAEA Nuclear Safety and Security Glossary, 20072022 (Interim) Edition, modified –
notes not included.]
3.4
item important to safety
item that is part of a safety group and/or whose malfunction or failure could lead to radiation
exposure of the site personnel or members of the public
[IAEA Safety Glossary, 2007 Edition]
equipment important to safety
equipment that is part of a safety group and/or whose malfunction or failure could lead to undue
radiation exposure of the site personnel or members of the public. Equipment including:
• those structures, systems and components that prevent anticipated operational occurrences
from leading to accident conditions;
• those features that are provided to mitigate the consequences of malfunction or failure of
structures, systems and components.
Note 1 to entry:
a) For usage consistent with IEC 61226 [11], equipment important to safety are as follows:
1) all I&C equipment performing Category A to Category C functions (in accordance with the IEC 61226 [11]
categorisation scheme);
2) all electrical equipment necessary to ensure emergency energy supply to this equipment in case of a loss of
normal power supply;
© IEC/IEEE 2024
3) all electrical equipment necessary to ensure ultimate energy supply in case of total loss of on-site power (if
selected as design extension condition to be mitigated).
b) For usage consistent with other IEEE documents and a Class 1E categorization; for equipment important to
safety, qualification is essential to the following:
1) electric equipment and systems that are essential to emergency reactor shutdown, containment isolation,
reactor core cooling, and containment and reactor heat removal, or;
2) electric equipment that are otherwise essential in preventing significant release of radioactive material to the
environment.
Note 2 to entry: Users of this document are advised that Class 1E is a functional term. Equipment and systems are
to be classified Class 1E only if they fulfil the functions listed in the definition. Identification of systems or equipment
as Class 1E based on anything other than their function is an improper use of the term and should be avoided.
[SOURCE: IEC/IEEE 60780-323:2016, 3.12]
3.5
tactile observation
qualitative assessment of a polymer’s condition through the physical examination of the exterior
of a material as observed by a knowledgeable person who, via experience or training, can
deduce degradation based on the hardness or softness of the material by lightly bending or
pressing a fingernail into the surface and via their knowledge and experience, or training can
deduce degradation based on the observed condition to assess if quantitative assessments are
warranted
3.6
visual observation
qualitative assessment of a polymer’s condition through the visible examination of the exterior
of material as observed by a knowledgeable person who, via experience or training, can deduce
degradation based on the observed condition to assess if quantitative assessments are
warranted
3.7
qualified condition
condition of an equipment, prior to the start of a design basis event, for which the equipment
was demonstrated to meet the design requirements for the specified service conditions. This
could include certain post accident cooling and monitoring systems that are expected to remain
operational
[SOURCE: IEC/IEEE 60780-323:2016, 3.19]
3.8
qualified life
period for which a structure, system or component has been demonstrated, through testing,
analysis or experience, to be capable of functioning within acceptance criteria during specific
operating conditions while retaining the ability to perform its safety functions in accident
conditions for a design basis accident or a design basis earthquake
[SOURCE: IAEA Nuclear Safety and Security Glossary, 20072022 (Interim) Edition]
3.9
service life
period from initial operation to final withdrawal from service of a structure, system or component
[SOURCE: IAEA Nuclear Safety and Security Glossary, 20072022 (Interim) Edition]
3.10
design basis events
postulated events used in the design to establish the acceptable performance requirements for
the structures, systems, and components

– 12 – IEC/IEEE 62582-1:2024 RLV
© IEC/IEEE 2024
[SOURCE: IEEE Standards Dictionary Online]
3.11
service conditions
actual physical states or influences during the service life of equipment, including normal
operating conditions, abnormal operating conditions, design basis event conditions and
conditions following a design basis event and design extension conditions
[SOURCE: IAEA Safety Glossary, 2007, modified, addition of “design extension conditions” and
use of term “equipment instead of “structure, system or component”]
3.12
ageing
general process in which characteristics of a system or component gradually change with time
or use
[SOURCE: IEC/IEEE 60780-323:2016, 3.2]
3.13
accelerated ageing
method of equipment testing in which the ageing associated with longer term service conditions
is simulated in a short time
Note 1 to entry: Usually, accelerated ageing attempts to simulate natural ageing effects by application of stressors
representing pre-service and service conditions, but with differences in intensity, duration and the manner of
application.
[SOURCE: IAEA Nuclear Safety and Security Glossary, 2022 (interim) Edition]
4 Condition indicators
4.1 General
Condition monitoring should only be applied if there is a known relationship between the ageing
degradation of the component monitored and the degradation of the equipment’s safety
function. This relationship should be established during equipment qualification. The
relationship should take into account any diffusion limited rate effects that occur during
accelerated ageing with high acceleration factors.
The condition indicator shall be measurable, change monotonically with time, be linked to the
functional degradation of the qualified equipment, and have a consistent trend from unaged
through the limit of the qualified pre-accident condition, and applied according to
IEC/IEEE 60780-323.
This trend should be established during the pre-ageing part of the equipment qualification.
When establishing the trend of condition indicators with ageing time, it is important that
acceleration factors (both thermal and radiation) are kept as small as practical. See Annex A
for additional information on diffusion limited oxidation (DLO).
Condition monitoring programs rely on measurable indicators that provide insight into the
overall degradation of the materials. To perform measurements of the condition of naturally
aged components, a sample shall either be taken destructively or the measurements shall be
made on the material in the field in a non-destructive way. The latter methods are preferred
since they allow the material to be studied without interrupting operation; however, it is often
difficult to perform these types of measurements directly in the field with the required degree of
repeatability and accuracy.
© IEC/IEEE 2024
In organic polymeric materials, ageing occurs that may can adversely impact the important
safety function through a range of chemical reactions, including chain scission and cross-
linking, which alter the polymeric structure. For condition monitoring programs, it becomes
imperative to find methods that, either directly or indirectly, follow the progress of these
reactions. A large number of methods exist to perform this task, which makes it difficult to
provide an overview of each individual technique. Instead, this document will focus on general
groups of methods. The overall description of these groups is provided in 4.2 through 4.6.
4.2 Chemical indicators
As mentioned above, the degradation mechanism for organic polymeric materials follows from
a series of chemical reactions in which the chemical structure of the polymer is altered. The
progressive change in the chemistry of the material provides an opportunity to monitor the
degradation throughout its ageing. Numerous techniques exist to perform this task, some which
monitor the polymer chain degradation itself and others which monitor side reactions which are
related to the degradation.
4.3 Physical indicators
Another key family of indicators includes techniques which monitor the material’s physical
properties. The degradation of organic polymeric materials manifests itself in changes to these
physical properties (i.e. tensile strength, elongation, and hardness). By measuring these
physical characteristics, it is possible to create a correlation with the aged condition of the
material.
4.4 Electrical indicators
A third category of techniques involves measuring electrical properties of the materials. Many
of these techniques were developed for polymeric materials used in electrical insulation. Within
this family there are two basic subsets of methods. The first subset involves measuring the
dielectric properties of the materials.
A second subset of methods monitors the electrical response of systems under normal
operation. In these cases, a signal is passed through the electrical system and any changes
from baseline are detected. These changes could be signs of degradation, whether through
ageing or through physical damage.
ndicators
4.5 MiscellaneousOther i
As new technologies are developed and implemented, it becomes necessary to develop
condition monitoring methods to keep pace. As such, some methods are developed specifically
for certain types of materials.
4.6 Visual and tactile observation
Visual and tactile testing methods are non-intrusive testing techniques for accessible
components. The purpose of this physical inspection method is to identify cracks,
discolouration, visible contamination of the components, the presence of chemicals or oils, and
other local damage such as swelling or deformation, to provide a qualitative assessment of the
condition of for example a cable’s jacket material that could indicate problems with the
insulation.
Visual and tactile methods may be used as a screening tool for ageing assessment and indicate
that further evaluation is necessary by applying other methods in accordance with the different
parts of IEC/IEEE 62582.
– 14 – IEC/IEEE 62582-1:2024 RLV
© IEC/IEEE 2024
5 Applicability of condition indicators to different types of organic polymeric
materials
There is currently no single condition monitoring method which is suitable for all organic or
polymeric materials. A basic requirement for inclusion in a part of the IEC/IEEE 62582 series is
that the condition indicators are sensitive to the effects of ageing. An important characteristic
of a useful condition indicator is that it shows a trend that changes monotonically with
degradation and can be correlated with the safety related performance. An indicator that does
not change for a long time and then suddenly undergoes drastic changes is not useful for
prognostic applications. This can be the case with mechanical condition monitoring on semi-
crystalline materials, e.g. cross-linked polyethylene and thermosetting resins, dependent on the
formulation.
Information on the applicability of various condition indicators to different polymeric materials
used in instrument and control equipment in nuclear power plants can be found in NUREG/CR-
7000 and in IAEA-TECDOC-1188, see Bibliography IAEA-TECDOC-1188 [12], IAEA-TECDOC-
1825 [3] and in EPRI 1022969 [14].
6 Destructive and non-destructive condition monitoring
A condition monitoring method may can be considered destructive or non-destructive,
depending on whether the measurement or the sampling of material used for the measurement
will affect operability or future ageing. Non-destructive use of condition monitoring is preferable
in field measurements but with presently available methods it is limited to a few types of
equipment, mainly cables, where the parts of the equipment of interest are accessible in the
field. In other cases, deposited samples or samples which can be replaced are needed
necessary to allow condition monitoring.
If deposited samples are available or where components can be replaced, a broader range of
condition monitoring methods can be considered, including destructive methods. In this case,
condition monitoring can be applied to all types of equipment where the ageing material –
normally organic polymeric materials used for electrical insulation, sealing, etc. can be
accessed.
7 Application of condition monitoring in equipment qualification and
management of ageing
7.1 General
Condition monitoring as part of qualification
...