IEC 62741:2015

IEC 62741 ®
Edition 1.0 2015-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Demonstration of dependability requirements – The dependability case

Démonstration des exigences de sûreté de fonctionnement – Argumentaire dans
le cadre de la sûreté de fonctionnement

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IEC 62741 ®
Edition 1.0 2015-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Demonstration of dependability requirements – The dependability case

Démonstration des exigences de sûreté de fonctionnement – Argumentaire

dans le cadre de la sûreté de fonctionnement

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 03.120.01; 21.020 ISBN 978-2-8322-2247-8

– 2 – IEC 62741:2015 © IEC 2015
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms, definitions and abbreviations . 7
3.1 Terms and definitions . 7
3.2 Abbreviations . 8
4 Background to the dependability case . 8
4.1 Principles and purpose . 8
4.2 Relationship between the dependability case and dependability plans . 9
4.3 Progressive assurance of dependability . 10
5 Principles of the dependability case . 11
5.1 Description of the dependability case . 11
5.2 Making claims in the dependability case . 12
5.3 Using evidence in the dependability case . 13
5.4 Evidence framework . 14
5.5 Dependability case report . 16
6 Development of the dependability case . 16
6.1 General . 16
6.2 Preparation of the dependability case . 17
6.3 Concept stage . 18
6.4 Development stage . 19
6.5 Realization stage . 19
6.6 Utilization stage . 20
6.7 Enhancement stage . 20
6.8 Retirement stage . 20
7 Assessing the adequacy of evidence . 21
Annex A (informative) Evidence framework . 22
A.1 General . 22
A.2 Abbreviations used only in this annex . 23
Annex B (informative) General requirements for the dependability case report . 40
B.1 General . 40
B.2 Elements required for the dependability case report . 40
B.3 Context and assumptions . 40
B.3.1 Stakeholders . 40
B.3.2 System description . 41
B.3.3 Dependability requirements . 41
B.3.4 Limitations on use . 41
B.3.5 Assumptions . 41
B.4 Risks . 41
B.5 Dependability plan . 42
B.6 The evidence framework . 42
B.7 Body of evidence . 42
B.8 Review of evidence to date . 42
B.9 Dependability claims and argument . 42

B.10 Conclusions and recommendations . 42
Annex C (informative) Checklist of points for assessing the adequacy of evidence . 44
Bibliography . 45

Figure 1 – Illustration of progressive assurance process . 11
Figure 2 – The development of claims . 12
Figure 3 – Establishment and development of the evidence framework . 15

Table A.1 – Evidence framework for system “X” . 24
Table A.2 – Evidence framework for system Y . 28

– 4 – IEC 62741:2015 © IEC 2015
INTERNATIONAL ELECTROTECHNICAL COMMISSION
______________
DEMONSTRATION OF DEPENDABILITY REQUIREMENTS –
THE DEPENDABILITY CASE
FOREWORD
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