IEC 62859:2016

IEC 62859 ®
Edition 1.0 2016-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Nuclear power plants – Instrumentation and control systems – Requirements for
coordinating safety and cybersecurity

Centrales nucléaires de puissance – Systèmes d'instrumentation et de contrôle-
commande – Exigences pour coordonner sûreté et cybersécurité

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IEC 62859 ®
Edition 1.0 2016-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Nuclear power plants – Instrumentation and control systems – Requirements for

coordinating safety and cybersecurity

Centrales nucléaires de puissance – Systèmes d'instrumentation et de contrôle-

commande – Exigences pour coordonner sûreté et cybersécurité

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 27.120.20 ISBN 978-2-8322-3719-9

– 2 – IEC 62859:2016 © IEC 2016
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 8
2 Normative references . 8
3 Terms and definitions . 9
4 Symbols and abbreviations . 11
5 Coordinating safety and cybersecurity at the overall architecture level . 12
5.1 General . 12
5.2 Fundamental and generic principles . 12
5.3 Thematic requirements and recommendations . 13
5.3.1 Delineation of security zones . 13
5.3.2 Provisions for coping with common cause failures (including diversity) . 13
5.3.3 Separation provisions . 14
5.3.4 Data communications . 14
6 Coordinating safety and cybersecurity at the individual system level. 14
6.1 General . 14
6.2 Fundamental and generic principles . 14
6.3 Safety and cybersecurity coordination during the I&C system lifecycle . 15
6.3.1 General . 15
6.3.2 Requirements and planning activities . 15
6.3.3 Design activities . 15
6.3.4 Implementation activities . 16
6.3.5 Verification and validation activities . 16
6.3.6 Installation and acceptance testing activities . 16
6.3.7 Operations and maintenance activities. 16
6.3.8 Change management . 16
6.3.9 Decommissioning activities . 16
6.4 Selected technical aspects of I&C systems constrained by safety and
cybersecurity . 17
6.4.1 General . 17
6.4.2 Logical access control for HMIs of I&C programmable digital systems in
control rooms . 17
6.4.3 Software modification . 17
6.4.4 Logging and audit capability . 18
6.4.5 Use of cryptography by I&C systems . 18
6.4.6 System availability and function continuity . 19
7 Organizational and operational issues . 19
7.1 Governance and responsibilities . 19
7.2 Coordination between safety and cybersecurity staff during operations . 19
7.3 Safety and cybersecurity culture . 19
7.4 Emergency response management . 19
Annex A (informative) Rationale for, and notes related to, the scope of this document . 21
A.1 General . 21
A.2 Inclusion of I&C programmable digital system not important to safety . 21
A.3 Exclusion of physical security, room access control and site security
surveillance systems . 21

A.4 Exclusion of non-malevolent actions and events . 21
A.5 Exclusion of development tools and platforms . 22
Bibliography . 23

– 4 – IEC 62859:2016 © IEC 2016
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
NUCLEAR POWER PLANTS –
INSTRUMENTATION AND CONTROL SYSTEMS –
REQUIREMENTS FOR COORDINATING SAFETY AND CYBERSECURITY

FOREWORD
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