ISO 23225
(Main)Corrosion control engineering life cycle in nuclear power plants — General requirements
Corrosion control engineering life cycle in nuclear power plants — General requirements
This standard specifies the general requirements of the corrosion control engineering life cycle in nuclear power plants. This standard applies to of various activities management of the corrosion control engineering life cycle in nuclear power plants.
Ingénierie du contrôle de la corrosion au cours du cycle de vie dans les centrales nucléaires — Exigences générales
General Information
Relations
Buy Standard
Standards Content (Sample)
FINAL DRAFT
International
Standard
ISO/FDIS 23225
ISO/TC 156/SC 1
Corrosion control engineering life
Secretariat: SAC
cycle in nuclear power plants —
Voting begins on:
General requirements
2025-04-17
Voting terminates on:
2025-06-12
RECIPIENTS OF THIS DRAFT ARE INVITED TO SUBMIT,
WITH THEIR COMMENTS, NOTIFICATION OF ANY
RELEVANT PATENT RIGHTS OF WHICH THEY ARE AWARE
AND TO PROVIDE SUPPOR TING DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO
LOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
INTERNATIONAL STANDARDS MAY ON OCCASION HAVE
TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL
TO BECOME STAN DARDS TO WHICH REFERENCE MAY BE
MADE IN NATIONAL REGULATIONS.
Reference number
ISO/FDIS 23225:2025(en) © ISO 2025
FINAL DRAFT
ISO/FDIS 23225:2025(en)
International
Standard
ISO/FDIS 23225
ISO/TC 156/SC 1
Corrosion control engineering life
Secretariat: SAC
cycle in nuclear power plants —
Voting begins on:
General requirements
Voting terminates on:
RECIPIENTS OF THIS DRAFT ARE INVITED TO SUBMIT,
WITH THEIR COMMENTS, NOTIFICATION OF ANY
RELEVANT PATENT RIGHTS OF WHICH THEY ARE AWARE
AND TO PROVIDE SUPPOR TING DOCUMENTATION.
© ISO 2025
IN ADDITION TO THEIR EVALUATION AS
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO
LOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
INTERNATIONAL STANDARDS MAY ON OCCASION HAVE
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL
or ISO’s member body in the country of the requester.
TO BECOME STAN DARDS TO WHICH REFERENCE MAY BE
MADE IN NATIONAL REGULATIONS.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland Reference number
ISO/FDIS 23225:2025(en) © ISO 2025
ii
ISO/FDIS 23225:2025(en)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 1
5 Objectives . 2
6 Corrosion sources . 2
7 Materials . 2
8 Technology . 3
9 Design . 3
10 Development . 4
11 Manufacturing . 4
12 Transportation and storage . 5
13 Construction and installation . 5
14 Commissioning and acceptance . 5
15 Operation . 6
16 Testing and inspection . 6
17 Maintenance and repair . 7
18 Life extension and scrapping . 7
19 Documents and records . 7
20 Resource management . 8
20.1 General requirement .8
20.2 General requirement .8
20.3 General requirement .8
20.4 Materials .8
20.5 Procedures .8
20.6 Environment .8
21 Comprehensive assessment . 8
Annex A (informative) Schematic diagrams of the composition of the three main types of
nuclear power plant . 10
Bibliography .12
iii
ISO/FDIS 23225:2025(en)
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.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types
of ISO document should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that
this may not represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 156, Corrosion of metals and alloys,
Subcommittee SC 1, Corrosion control engineering life cycle.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
iv
FINAL DRAFT International Standard ISO/FDIS 23225:2025(en)
Corrosion control engineering life cycle in nuclear power
plants — General requirements
1 Scope
This document specifies the general requirements of corrosion control engineering life cycle in nuclear
power plants.
This document applies to the corrosion control engineering in nuclear power plants.
2 Normative references
There are no normative references in this document.
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:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
corrosion control engineering life cycle in nuclear power plants
entire process of identification of the corrosion sources in nuclear power plants to control of corrosion
behaviour
Note 1 to entry: The entire process refers to the systematic engineering of selecting corrosion control materials and
technologies, as well as the design, construction, inspection, assessment and maintenance.
3.2
direct corrosion source
various factors that cause corrosion in direct contact with materials, such as environmental mediums and
acid solutions, alkali solutions and salt solutions
3.3
indirect corrosion source
various factors that cause corrosion without direct contact with materials, such as environmental conditions
and mediums working conditions
4 Principle
This document defines the corrosion control activities conducted throughout the entire engineering life cycle
in nuclear power plants. It identifies all related elements including the objectives, corrosion sources, materials,
technology, development, design, manufacturing, transportation and storage, construction and installation,
commissioning and acceptance, operation, testing and inspection, maintenance and repair, life extension and
scrapping, documents and records, resource management and comprehensive assessment. The requirements
of those elements are specified in accordance with holistic, systematic, coordinated and optimized principles.
The purpose of the requirements is to achieve the objectives (see Clause 5) under the premise of ensuring
public health, lives and property safety, national security and ecological environment safety.
ISO/FDIS 23225:2025(en)
5 Objectives
The corrosion control activities specified in this document aim at controlling corrosion effectively during
the entire engineering life cycle in nuclear power plants, and achieving the optimum benefits of safety, cost-
effectiveness, long-term operation and environmental protection.
6 Corrosion sources
6.1 The corrosion sources of nuclear power plants are classified as follows:
— direct corrosion sources, such as light water, heavy water, liquid metal, helium, boric acid solution, steam,
seawater, fresh water, soil, acid solution, alkali solution and salt soluti
...
ISO/FDIS 23225
ISO/TC 156/SC 1
Secretariat: SAC
Date: 2024-12-262025
Corrosion control engineering life cycle in nuclear power plants —
General requirements
FDIS stage
Warning for WD’s and CD’s
This document is not an ISO International Standard. It is distributed for review and comment. It is subject to change
without notice and may not be referred to as an International Standard.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which
they are aware and to provide supporting documentation.
ISO/FDIS 23225:20242025(en)
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication
may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying,
or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO
at the address below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: + 41 22 749 01 11
E-mail: copyright@iso.org
Website: www.iso.org
Published in Switzerland
iii
ISO/FDIS 23225:20242025(en)
Contents
Foreword . v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 1
5 Objectives . 2
6 Corrosion sources . 2
7 Materials . 2
8 Technology . 3
9 Design . 3
10 Development . 4
11 Manufacturing . 4
12 Transportation and storage . 5
13 Construction and installation . 5
14 Commissioning and acceptance . 5
15 Operation . 6
16 Testing and inspection . 6
17 Maintenance and repair . 6
18 Life extension and scrapping . 7
19 Documents and records . 7
20 Resource management . 8
20.1 General requirement . 8
20.2 General requirement . 8
20.3 General requirement . 8
20.4 Materials . 8
20.5 Procedures . 8
20.6 Environment . 8
21 Comprehensive assessment . 8
Annex A (informative) Schematic diagrams of the composition of the three main types of
nuclear power plant . 10
Bibliography . 13
iv
ISO/FDIS 23225:20242025(en)
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.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types of
ISO document should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent rights
in respect thereof. As of the date of publication of this document, ISO had not received notice of (a) patent(s)
which may be required to implement this document. However, implementers are cautioned that this may not
represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 156, Corrosion of metals and alloys,
Subcommittee SC 1, Corrosion control engineering life cycle.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
v
ISO/FDIS 23225:20242025(en)
Corrosion control engineering life cycle in nuclear power plants —
General requirements
1 Scope
This document specifies the general requirements of corrosion control engineering life cycle in nuclear power
plants.
This document applies to the corrosion control engineering in nuclear power plants.
2 Normative references
There are no normative references in this document.
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:
— ISO Online browsing platform: available at https://www.iso.org/obp
— IEC Electropedia: available at https://www.electropedia.org/
3.1 3.1
corrosion control engineering life cycle in nuclear power plants
entire process of identification of the corrosion sources in nuclear power plants to control of corrosion
behaviorbehaviour
Note 1 to entry: The entire process refers to the systematic engineering of selecting corrosion control materials and
technologies, as well as the design, construction, inspection, assessment, and maintenance.
3.2 3.2
direct corrosion source
various factors that cause corrosion in direct contact with materials, such as environmental mediums and acid
solutions, alkali solutions and salt solutions
3.3 3.3
indirect corrosion source
various factors that cause corrosion without direct contact with materials, such as environmental conditions
and mediums working conditions
4 Principle
This document defines the corrosion control activities conducted throughout the entire engineering life cycle
in nuclear power plants, and. It identifies all related elements including the objectives, corrosion sources,
materials, technology, development, design, manufacturing, transportation and storage, construction and
installation, commissioning and acceptance, operation, testing and inspection, maintenance and repair, life
extension and scrapping, documents and records, resource management and comprehensive assessment. The
requirements of those elements are specified in accordance with holistic, systematic, coordinated and
optimized principles. The purpose of the requirements is to achieve the objectives (see 5Clause 5)) under the
premise of ensuring public health, lives and property safety, national security and ecological environment
safety.
ISO/FDIS 23225:20242025(en)
5 Objectives
CorrosionThe corrosion control activities specified in this document aim at controlling corrosion effectively
during the entire engineering life cycle in nuclear power plants, and achieving the optimum benefits of safety,
cost-effectiveness, long-term operation and environmental protection.
6 Corrosion sources
6.1 6.1 The corrosion sources of nuclear power plants are classified as follows:
— direct corrosion sources, such as light water, heavy water, liquid metal, helium, boric acid solution, steam,
seawater, fresh water, soil, acid solution, alkali solution and salt solution, waste liquid, atmosphere,
dissolved hydrogen, dissolved oxygen and humidity;
— indirect corrosion sources, such as pressure, temperature, flow rate, radiation, stress field,
microorganisms and their metabolites and other working conditions;
— environmental corrosion sources, such as stray current interference and dissimilar metal contact resulting
in galvanic corrosion current interference;
— corrosion sources generated during corrosion.
6.2 6.2 Systematic, comprehensive and accurate investigation and identification should be carried out on
the corrosion sources involved at all stages.
6.3 6.3 When identifying corrosion sources, the differences between different reactor types of nuclear
power plant should be taken into account (see Appendix A). This process should cover the normal operating
and accident conditions of equipment and facilities in nuclear power plants.
6.4 6.4 Check and recognition of corrosion sources in nuclear power plants should be carried out through
the appropriate procedures.
7 Materials
7.1 7.1 Corrosion control materials may include the following:
— metallic materials, such as zirconium alloys, nickel-based alloys, stainless steel, carbon steel, low-alloy
steel, cast iron, copper alloys, titanium alloys and aluminium alloys;
— non-metallic materials, such as rubber, glass fibre reinforced plastics, plastics and coatings:;
— composite materials, such as steel-plastic composites.
7.2 7.2 Select materials that can resist the corrosion sources identified in 6 to ensure they are
compatible with processes such as design, manufacturing and operation.
7.3 7.3 The selection of materials should followtake into account:
— corrosion resistance, physical properties (such as heat resistance and electrical conductivity), mechanical
properties (such as strength, hardness and plasticity) and processing performance (such as machining,
casting and welding) of the materials;
— the scientific nature, technicality, economy and green environmental protection of the materials;
— materials performance in similar project;
ISO/FDIS 23225:20242025(en)
— materials used in irradiation areas have good anti-irradiation and decontamination properties, and
materials in contact with the reactor coolant should be limited elements that can easily lead to increased
radioactive activation.
7.4 7.4 Check and validation of the selected materials should be carried out through the appropriate
procedures.
8 Technology
8.1 8.1 Select corrosion control technologies that can resist t
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.