IEC 62508
Edition 1.0 2010-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Guidance on human aspects of dependability
Lignes directrices relatives aux facteurs humains dans la sûreté de
fonctionnement
IEC 62508:2010
®
colour
inside
IEC 62508
Edition 1.0 2010-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Guidance on human aspects of dependability
Lignes directrices relatives aux facteurs humains dans la sûreté de
fonctionnement
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
XA
ICS 03.120.01
PRICE CODE
CODE PRIX
ISBN 978-2-88912-023-9
® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
®
colour
inside
– 2 – 62508 © IEC:2010
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 ........................................................................................................10
4 Human aspects...............................................................................................................10
4.1 Overview ...............................................................................................................10
4.2 Components of the system and their interactions...................................................11
4.2.1 Introductory remark ...................................................................................11
4.2.2 Goals.........................................................................................................11
4.2.3 Humans.....................................................................................................12
4.2.4 Machine (interactive system) .....................................................................12
4.2.5 Social and physical environment................................................................13
4.2.6 Output .......................................................................................................13
4.2.7 Feedback from the machine to the person .................................................13
4.3 Human characteristics...........................................................................................14
4.3.1 Introductory remark ...................................................................................14
4.3.2 Human limitations......................................................................................14
4.3.3 Comparison of humans and machines .......................................................14
4.4 Human performance shaping factors .....................................................................15
4.4.1 External performance shaping factors........................................................16
4.4.2 Internal performance shaping factors.........................................................16
4.5 Human reliability analysis (HRA) ...........................................................................16
4.5.1 Overview ...................................................................................................16
4.5.2 Identifying the potential for human error ....................................................17
4.5.3 Analysing human failures to define countermeasures ................................17
4.5.4 Quantification of human reliability..............................................................18
4.6 Critical systems.....................................................................................................18
4.7 Human-centred design guidelines..........................................................................19
4.8 Human-centred design process .............................................................................20
4.8.1 Human-centred design principles within the design process ......................20
4.8.2 Human-centred design activities ................................................................21
5 Human-oriented design in the system lifecycle ...............................................................21
5.1 Overview ...............................................................................................................21
5.2 The system life cycle.............................................................................................22
5.3 Integrating human-oriented design in systems engineering....................................23
6 Human-oriented design at each life cycle stage..............................................................24
6.1 Overview ...............................................................................................................24
6.2 Concept/definition stage........................................................................................24
6.2.1 Concept.....................................................................................................24
6.2.2 Human-centred design planning ................................................................24
6.2.3 Understanding needs.................................................................................25
6.2.4 System requirements.................................................................................25
6.2.5 Human-centred design requirements .........................................................25
62508 © IEC:2010 – 3 –
6.3
Design/development..............................................................................................26
6.4 Realization/implementation....................................................................................26
6.5 Operation/maintenance .........................................................................................27
6.6 Enhancement ........................................................................................................27
6.7 Retirement/decommission .....................................................................................28
6.8 Outsourcing projects and related human-centred design issues.............................28
7 Human-centred design methods .....................................................................................29
7.1 Classification of human-centred design activities...................................................29
7.2 Applications of human-centred design methods.....................................................30
Annex A (informative) Examples of HRA methods................................................................31
Annex B (informative) Summary of human-oriented design activities and their impact
on system dependability .......................................................................................................37
Annex C (informative) Best practices for human-centred design...........................................41
Bibliography..........................................................................................................................47
Figure 1 – Components of the system and their interactions .................................................11
Figure 2 – Human performance shaping factors ....................................................................16
Figure 3 – Simple model of human information processing....................................................17
Figure 4 – Human-centred design activities ..........................................................................21
Figure 5 – Human aspects of the system life cycle................................................................23
Table 1 – People who influence dependability.......................................................................12
Table A.1 – HRA methods and their application ....................................................................31
Table B.1 – Automation ........................................................................................................37
Table B.2 – Design for maintainability...................................................................................37
Table B.3 – Computer-human interface.................................................................................38
Table B.4 – Incorporation of displays, controls and alarm functions ......................................39
Table B.5 – Incorporation of input devices ............................................................................39
Table B.6 – Environment.......................................................................................................40
Table B.7 – Safety ................................................................................................................40
Table B.8 – Security .............................................................................................................40
Table C.1 – Examples of methods and techniques that contribute to best practices ..............41
– 4 – 62508 © IEC:2010
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
GUIDANCE ON HUMAN ASPECTS OF DEPENDABILITY
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
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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
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
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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 62508 has been prepared by IEC technical committee 56:
Dependability.
This first edition cancels and replaces IEC/PAS 62508 published in 2007.
The text of this standard is based on the following documents:
FDIS Report on voting
56/1365/FDIS 56/1373/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.
