EN 62138:2009

SLOVENSKI STANDARD
01-november-2009
1XNOHDUQHHOHNWUDUQH0HULOQDLQQDG]RUQDRSUHPD]D]DJRWDYOMHQMHYDUQRVWL
=QDþLOQRVWLSURJUDPVNHRSUHPHUDþXQDOQLãNLKVLVWHPRYNLL]YDMDMRNDWHJRULML
IXQNFLM%DOL&,(&
Nuclear power plants - Instrumentation and control important for safety - Software
aspects for computer-based systems performing category B or C functions
Kernkraftwerke - Leittechnik für Systeme mit sicherheitstechnischer Bedeutung -
Softwareaspekte für rechnerbasierte Systeme zur Realisierung von Funktionen der
Kategorie B oder C
Centrales nucléaires - Instrumentation et contrôle commande importants pour la sûreté -
Aspects logiciels des systèmes informatisés réalisant des fonctions de catégorie B ou C
Ta slovenski standard je istoveten z: EN 62138:2009
ICS:
27.120.20 Jedrske elektrarne. Varnost Nuclear power plants. Safety
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN 62138
NORME EUROPÉENNE
August 2009
EUROPÄISCHE NORM
ICS 27.120.20
English version
Nuclear power plants -
Instrumentation and control important for safety -
Software aspects for computer-based systems
performing category B or C functions
(IEC 62138:2004)
Centrales nucléaires -  Kernkraftwerke -
Instrumentation et contrôle-commande Leittechnik für Systeme
importants pour la sûreté - mit sicherheitstechnischer Bedeutung -
Aspects logiciels des systèmes Softwareaspekte für rechnerbasierte
informatisés réalisant des fonctions Systeme zur Realisierung von Funktionen
de catégorie B ou C der Kategorie B oder C
(CEI 62138:2004) (IEC 62138:2004)

This European Standard was approved by CENELEC on 2009-07-01. 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 Central Secretariat 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 Central Secretariat has the same status as the official versions.

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

CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung

Central Secretariat: Avenue Marnix 17, B - 1000 Brussels

© 2009 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 62138:2009 E
Foreword
The text of the International Standard IEC 62138:2004, prepared by SC 45A, Instrumentation and
control of nuclear facilities, of IEC TC 45, Nuclear instrumentation, was submitted to the formal vote
and was approved by CENELEC as EN 62138 on 2009-07-01 without any modification.
The following dates were fixed:

– latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement (dop) 2010-07-01

– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2012-07-01
Annex ZA has been added by CENELEC.
__________
Endorsement notice
The text of the International Standard IEC 62138:2004 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 61508-3 NOTE  Harmonized as EN 61508-3:2001 (not modified).
IEC 61508-4 NOTE  Harmonized as EN 61508-4:2001 (not modified).
IEC 61511-1 NOTE  Harmonized as EN 61511-1:2004 (not modified).
ISO 9000-3 NOTE  Harmonized as EN ISO 9000-3:1997 (not modified).
ISO 9001 NOTE  Harmonized as EN ISO 9001:2008 (not modified).
__________
- 3 - EN 62138:2009
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications

The following referenced documents are indispensable for the application 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  When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD
applies.
Publication Year Title EN/HD Year
1)
IEC 61226 - Nuclear power plants - Instrumentation - -
and control systems important to safety -
Classification of instrumentation and
control functions
IEC 61513 2001 Nuclear power plants - Instrumentation - -
and control for systems important to
safety - General requirements for systems

1)
Undated reference.
NORME CEI
INTERNATIONALE
IEC
INTERNATIONAL
Première édition
STANDARD
First edition
2004-01
Centrales nucléaires –
Instrumentation et contrôle-commande
importants pour la sûreté –
Aspects logiciels des systèmes informatisés
réalisant des fonctions de catégorie B ou C

Nuclear power plants –
Instrumentation and control important for safety –
Software aspects for computer-based systems
performing category B or C functions
 IEC 2004 Droits de reproduction réservés  Copyright - all rights reserved
Aucune partie de cette publication ne peut être reproduite ni No part of this publication may be reproduced or utilized in any
utilisée sous quelque forme que ce soit et par aucun procédé, form or by any means, electronic or mechanical, including
électronique ou mécanique, y compris la photocopie et les photocopying and microfilm, without permission in writing from
microfilms, sans l'accord écrit de l'éditeur. the publisher.
International Electrotechnical Commission, 3, rue de Varembé, PO Box 131, CH-1211 Geneva 20, Switzerland
Telephone: +41 22 919 02 11 Telefax: +41 22 919 03 00 E-mail: inmail@iec.ch Web: www.iec.ch
CODE PRIX
X
PRICE CODE
Commission Electrotechnique Internationale
International Electrotechnical Commission
МеждународнаяЭлектротехническаяКомиссия
Pour prix, voir catalogue en vigueur
For price, see current catalogue

62138  IEC:2004 – 3 –
CONTENTS
FOREWORD.5
INTRODUCTION.9

1 Scope.11
2 Normative references.11
3 Terms, definitions and abbreviations .13
4 Key concepts and assumptions.23
4.1 Types of software.23
4.2 Types of data.25
4.3 Software and System Safety Lifecycles .25
4.4 Gradation principles.31
5 Requirements for the software of I&C systems performing category C functions .35
5.1 General requirements.35
5.2 Selection of pre-developed software.43
5.3 Software requirements specification .45
5.4 Software design.49
5.5 Implementation of new software .51
5.6 Software aspects of system integration .53
5.7 Software aspects of system validation .53
5.8 Installation of software on site .55
5.9 Anomaly reports.55
5.10 Software modification.55
6 Requirements for the software of I&C systems performing category B functions .57
6.1 General requirements.57
6.2 Selection of pre-developed software.65
6.3 Software requirements specification .75
6.4 Software design.79
6.5 Implementation of new software .83
6.6 Software aspects of system integration .87
6.7 Software aspects of system validation .87
6.8 Installation of software on site .89
6.9 Anomaly reports.91
6.10 Software modification.91

Bibliography.95

Figure 1 – Typical software parts in computer-based I&C systems.23
Figure 2 – Activities of the System Safety Lifecycle (as defined by IEC 61513).25
Figure 3 – Software related activities in the System Safety Lifecycle .27
Figure 4 – Development activities of the IEC 62138 Software Safety Lifecycle.29
Figure 5 – Process for providing evidence of correctness for pre-developed software of
an I&C system of safety class 2. .31

62138  IEC:2004 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
NUCLEAR POWER PLANTS –
INSTRUMENTATION AND CONTROL IMPORTANT FOR SAFETY –
SOFTWARE ASPECTS FOR COMPUTER-BASED SYSTEMS
PERFORMING CATEGORY B OR C FUNCTIONS

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 provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
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 I
...