SIST EN IEC 62646:2019

SLOVENSKI STANDARD
SIST EN IEC 62646:2019
01-september-2019
Jedrske elektrarne - Nadzorne sobe - Računalniški postopki (IEC 62646:2016)
Nuclear power plants - Control rooms - Computer-based procedures (IEC 62646:2016)
Kernkraftwerke - Warten - Rechnerunterstützte Prozeduren (IEC 62646:2016)
Centrales nucléaires de puissance - Salles de commande - Procédures informatisées
(IEC 62646:2016)
Ta slovenski standard je istoveten z: EN IEC 62646:2019
ICS:
27.120.20 Jedrske elektrarne. Varnost Nuclear power plants. Safety
SIST EN IEC 62646:2019 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN IEC 62646:2019

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SIST EN IEC 62646:2019


EUROPEAN STANDARD EN IEC 62646

NORME EUROPÉENNE

EUROPÄISCHE NORM
June 2019
ICS 27.120.20

English Version
Nuclear power plants - Control rooms - Computer-based
procedures
(IEC 62646:2016)
Centrales nucléaires de puissance - Salles de commande - Kernkraftwerke - Warten - Rechnerunterstützte Prozeduren
Procédures informatisées (IEC 62646:2016)
(IEC 62646:2016)
This European Standard was approved by CENELEC on 2019-06-17. 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
© 2019 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
 Ref. No. EN IEC 62646:2019 E

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SIST EN IEC 62646:2019
EN IEC 62646:2019 (E)

European foreword
This document (EN IEC 62646:2019) consists of the text of IEC 62646:2016 prepared by IEC/SC
45A: "Instrumentation, control and electrical power systems of nuclear facilities", of IEC/TC 45:
"Nuclear instrumentation".
The following dates are fixed:
• latest date by which this document has to be (dop) 2020-06-17
implemented at national level by publication of an
identical national standard or by endorsement
• latest date by which the national standards (dow) 2022-06-17
conflicting with this document have to be
withdrawn
As stated in the nuclear safety directive 2009/71/EURATOM, Chapter 1, Article 2, item 2, Member
States are not prevented from taking more stringent safety measures in the subject-matter covered by
the Directive, in compliance with Community law. In a similar manner, this European standard does
not prevent Member States from taking more stringent nuclear safety and/or security measures in the
subject-matter covered by this standard.
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 62646:2016 was approved by CENELEC as a European
Standard without any modification.

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SIST EN IEC 62646:2019
EN IEC 62646:2019 (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 When 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 60880 -  Nuclear power plants - Instrumentation EN 60880 -
and control systems important to safety -
Software aspects for computer-based
systems performing category A functions
IEC 60964 2009 Nuclear power plants - Control rooms - EN 60964 2010
Design
IEC 60965 2016 Nuclear power plants - Control rooms - EN 60965 2016
Supplementary control room for reactor
shutdown without access to the main
control room
IEC 61513 -  Nuclear power plants - Instrumentation EN 61513 -
and control important to safety - General
requirements for systems
IEC 61772 2009 Nuclear power plants - Control rooms - EN 61772 2013
Application of visual display units (VDUs)
IEC 61839 -  Nuclear power plants - Design of control EN 61839 -
rooms - Functional analysis and
assignment
IEC 62138 -  Nuclear power plants - Instrumentation EN 62138 -
and control systems important to safety -
Software aspects for computer-based
systems performing category B or C
functions
IEC 62241 2004 Nuclear power plants - Main control room - EN 62241 2015
Alarm functions and presentation
ISO 11064 series Ergonomic design of control centres EN ISO 11064 series
ISO 11064-1 -  Ergonomic design of control centres - Part EN ISO 11064-1 -
1: Principles for the design of control
centres
ISO 11064-3 -  Ergonomic design of control centres - Part EN ISO 11064-3 -
3: Control room layout
ISO 11064-4 -  Ergonomic design of control centres - Part EN ISO 11064-4 -
4: Layout and dimensions of workstations
ISO 11064-5 -  Ergonomic design of control centres - Part EN ISO 11064-5 -
5: Displays and controls

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SIST EN IEC 62646:2019




IEC 62646

®


Edition 2.0 2016-10




INTERNATIONAL



STANDARD




NORME



INTERNATIONALE
colour

inside










Nuclear power plants – Control rooms – Computer-based procedures



Centrales nucléaires de puissance – Salles de commande – Procédures


informatisées

















INTERNATIONAL

ELECTROTECHNICAL

COMMISSION


COMMISSION

ELECTROTECHNIQUE


INTERNATIONALE




ICS 27.120.20 ISBN 978-2-8322-3650-5



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 . 5
INTRODUCTION . 8
1 Scope . 11
1.1 Object of this standard . 11
1.2 Context leading to development and use of CPB . 11
1.3 CBP overview . 11
1.4 Use of this standard with related standards . 12
1.5 Organisation of this standard . 12
2 Normative references. 13
3 Terms and definitions . 14
4 Abbreviated terms . 16
5 CBP policy and conceptual requirements. 16
5.1 General . 16
5.2 Computerisation policy . 17
5.2.1 General . 17
5.2.2 Rationale underlying the implementation of CBP . 17
5.2.3 The scope of CBP . 18
5.3 Families of CBP . 19
5.4 Overview of computerisation features . 20
5.4.1 General . 20
5.4.2 Global requirements for computerisation . 20
5.4.3 Provision of guidance to operator . 21
5.4.4 Provision of procedure based automation . 22
5.5 Output documentation . 22
5.6 Design extension conditions . 23
6 Contexts of use of CBP . 23
6.1 General . 23
6.2 Application environments of CBP use . 23
6.2.1 General . 23
6.2.2 Use of CBP in computerised control rooms . 23
6.2.3 Use of CBP in a conventional or hybrid main control room . 24
6.2.4 Use of CBP in conjunction with paper-based procedures . 24
6.2.5 Use of CBP outside the main control room . 25
6.3 Forms of CBP assistance to operator activities . 25
6.3.1 General . 25
6.3.2 Assistance to primary activities of the operator . 25
6.3.3 Assistance to secondary activities of the operator . 25
6.4 Assistance with operator coordination . 26
6.5 Output documentation . 26
7 CBP system and functional requirements . 27
7.1 General . 27
7.2 Safety requirements . 27
7.3 HMI considerations . 28
7.4 Integration of the CBP system into the DPDS . 28
7.5 CBP system implemented externally to the DPDS . 28

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7.5.1 General . 28
7.5.2 Sizing and dependability requirements . 29
7.5.3 Connections between the CBP system and the DPDS . 29
7.5.4 Coherent maintenance of both systems . 29
7.6 CBP system failure . 29
7.7 Output documentation . 30
8 Detailed design requirements . 31
8.1 General . 31
8.2 Basic CBP features . 31
8.2.1 General . 31
8.2.2 Basic features necessary for CBP . 31
8.2.3 Presentation rules . 31
8.2.4 CBP display format layout . 32
8.2.5 Requirements for presentation of individual display elements . 32
8.3 Information presented by the CBP . 33
8.3.1 General . 33
8.3.2 Information for Family 1 CBP . 33
8.3.3 Information for Family 2 CBP . 33
8.3.4 Information for Family 3 CBP . 34
8.4 Navigation. 34
8.4.1 General . 34
8.4.2 Navigation for Family 1 CBP . 34
8.4.3 Navigation for Family 2 and Family 3 CBP . 34
8.5 CBP guidance . 35
8.5.1 General . 35
8.5.2 CBP selection, accessibility and execution . 35
8.5.3 Diagnosis assistance . 35
8.5.4 Decision assistance . 35
8.5.5 Computerisation of CBP guidance . 36
8.6 Procedure-based automation . 36
8.6.1 General . 36
8.6.2 Interactions between operators and procedure based automation . 37
8.6.3 Design of CBP to control the plant . 37
8.7 Other CBP facilities . 38
8.8 Output documentation . 38
9 CBP life cycle . 38
9.1 General . 38
9.2 Project organisation . 39
9.3 Project team . 39
9.4 CBP detailed design and implementation quality assurance (QA) . 39
9.5 Verification and validation programme . 40
9.6 Verification and validation of CBP . 40
9.6.1 General . 40
9.6.2 Technical verification of CBP . 41
9.6.3 Functional and ergonomic validation . 41
9.6.4 Output documentation . 42
9.7 Implementation of CBP in NPP . 42
9.8 Output documentation . 43
9.9 Training of the operating staff . 44

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9.10 CBP and CBP system maintenance . 44
9.11 Feedback of experience . 44
Bibliography . 45

Table 1 – CBP families . 19

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IEC 62646:2016 © IEC 2016 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

NUCLEAR POWER PLANTS – CONTROL ROOMS –
COMPUTER-BASED PROCEDURES

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.
International Standard IEC 62646 has been prepared by subcommittee 45A: Instrumentation,
control and electrical systems of nuclear facilities, of IEC technical committee 45: Nuclear
instrumentation.
This second edition cancels and replaces the first edition published in 2012. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) clarification of the way in which the standard is to be used in conjunction with related
standards (in 1.4);
b) replacement, when necessary, of HMI system by DPDS (abbreviation added in Clause 4);
c) new titles for 5.2.2 and 5.2.3 to more closely represent their content;
d) text improvement in 5.2.2, to present the CBP system as a part of the I&C architecture
rather than a stand alone system;
e) text improvement in 5.2.3 and 7.2 to clarify links between safety and CBP;

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SIST EN IEC 62646:2019
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f) new definition of CPB families in 5.3;
g) addition of generic recommendations for computerization in 5.4.2;
h) addition of generic recommendations for CBP guidance in 5.4.3;
i) improvements regarding use of CBP in 5.4.4;
j) addition of 5.6, named “Design extension conditions”;
k) addition of reference standards in 6.2.1;
l) addition of a criterion related to detail compatibility between CBP and operating formats in
6.2.2;
m) addition of references related to HMI in 6.2.3;
n) addition of 7.3 to deal with HMI aspects;
o) text improvement regarding integration of the CBP system into the DPDS in 7.3;
p) text improvement regarding implementation of the CBP into a system independent of the
DPDS in 7.4;
q) text improvement regarding the CBP system failure in 7.6;
r) note added to detail the different types of feedbacks in 8.5.4;
s) text improvement to detail interactions between operators and procedure based
automation in 8.6.2;
t) text improvement regarding design of CBP to control the plant in 8.6.3;
u) clarification of the content of the V&V programme for CBP in 9.5;
v) clarification regarding CBP programming in 9.4;
w) inversion of subclauses 9.4 and 9.5;
x) clarification of the content and requirements of the V&V in 9.6;
y) change of title of 9.7.
The text of this standard is based on the following documents:
FDIS Report on voting
45A/1098/FDIS 45A/1110/RVD

Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
IEC 62646 is to be read in conjunction with IEC 60964:2009 and IEC 61839:2000.

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IEC 62646:2016 © IEC 2016 – 7 –
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC website under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.

IMPORTANT – The 'colour inside' logo on the cover page of this publication 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.

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SIST EN IEC 62646:2019
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INTRODUCTION
a) Technical background, main issues and organisation of the standard
This IEC standard focuses on computerisation of procedures used by the operating staff.
Procedures have always contributed to a large extent to nuclear power plant (NPP) safety and
availability and, now, the use of computer technology to provide enhanced guidance to the
plant operators is increasing and becoming current practice. This standard also provides
guidance for the decision of the extent to which the procedures should be computerised.
It is intended that the standard be used by nuclear power plant designers, utilities operating
staff, systems evaluators and by regulatory inspectors.
In June 2013 during the IEC SC 45A meeting held in Moscow, the decision was made to
revise IEC 62646 with the lessons learned from the Tokyo Electric Power Company (TEPCO)
Fukushima Daiichi accident and the late comments from the national committee of Canada.
The resulting improvements are listed in the Foreword of the Standard.
b) Situation of the current standard in the structure of the IEC SC 45A standard series
IEC 62646 is the third level IEC SC 45A document tackling the generic issue of computerised
procedures.
As indicated in the Foreword, IEC 62646 is to be read with IEC 60964 and IEC 61839.
IEC 60964 – supported by IEC 61227, IEC 61771 and IEC 61772 – is the appropriate IEC
SC 45A document providing guidance on operator controls, verification and validation of
design, application of visual display units in the control room, whereas IEC 61839 establishes
functional analysis and assignment guidance for allocating functions between operators and
systems.
For more details on the structure of the IEC SC 45A standard series, see the item d) of this
introduction.
c) Recommendations and limitations regarding the application of the standard
It is important to note that this standard establishes no additional functional requirements for
safety systems.
This standard deals with technical requirements and human factor engineering related to
computer-based procedures (CBP). However it does not provide detailed guidance on
ergonomic design of control centres as it is treated in the ISO 11064 series of standards, nor
on task allocation between humans and systems dealt with in IEC 61839 and on cyber
security, which is developed in IEC 62645. It also excludes the organisation for maintenance
of procedures.
Aspects for which requirements and recommendations have been provided in this standard
are:
• the establishment of a policy for computerisation of procedures, especially which types of
procedure should be computerised and to what extent. The different families of CBP to be
aimed at, with their associated features, are then defined. Finally, the safety aspects of
CBP are considered,
• the use of CBP inside and outside of the MCR (main control room), in possible conjunction
with paper-based procedures, as well as the assistance provided to operator activities,
including user coordination,
• safety and non safety design requirements for the digital system processing CBP, and
considerations about what to do in case of failure of this system,

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IEC 62646:2016 © IEC 2016 – 9 –
• detailed requirements and recommendations related to the functional features of CBP,
from the basic ones to the most sophisticated ones, i.e. information, navigation, guidance
and plant con
...