IEC 61511-1:2003

Functional safety - Safety instrumented systems for the process industry sector - Part 1: Framework, definitions, system, hardware and software requirements

gives requirements for the specification, design, installation, operation and maintenance of a safety instrumented system, so that it can be confidently entrusted to place and/or maintain the process in a safe state. This standard has been developed as a process sector implementation of IEC 61508. The contents of the corrigendum of November 2004 have been included in this copy. It has the status of a horizontal standard in accordance with IEC Guide 108.

Sécurité fonctionnelle - Systèmes instrumentés de sécurité pour le domaine de la production par processus - Partie 1: Cadre, définitions, exigences pour le système, le matériel et le logiciel

permet de définir des prescriptions relatives aux spécifications, à la conception, à l'installation, à l'exploitation et à l'entretien d'un système instrumenté de sécurité, de telle manière qu'il puisse être mis en oeuvre en toute confiance, et ainsi établir et/ou maintenir les processus dans un état de sécurité convenable. La présente norme a été conçue pour être une mise en uvre de la norme internationale CEI 61508 "Sécurité fonctionnelle des systèmes électriques/électroniques/ électroniques programmables relatifs à la sécurité" dans le domaine de l'industrie des processus. Le contenu du corrigendum de novembre 2004 a été pris en considération dans cet exemplaire. Elle a le statut d'une norme horizontale conformément au Guide 108 de la CEI.

General Information

• Status: Published
• Publication Date: 29-Jan-2003
• ICS: 13.110 - Safety of machinery
• ICS: 25.040.01 - Industrial automation systems in general
• Technical Committee: SC 65A - System aspects
• Current Stage: DELPUB - Deleted Publication
• Completion Date: 24-Feb-2016

Relations

• Corrected By: IEC 61511-1:2003/COR1:2004 - Corrigendum 1 - Functional safety - Safety instrumented systems for the process industry sector - Part 1: Framework, definitions, system, hardware and software requirements
• Effective Date: 05-Sep-2023
• Revised: IEC 61511-1:2016 - Functional safety - Safety instrumented systems for the process industry sector - Part 1: Framework, definitions, system, hardware and application programming requirements
• Effective Date: 05-Sep-2023

Standards Content (Sample)

INTERNATIONAL IEC
STANDARD
61511-1
First edition
2003-01
Functional safety –
Safety instrumented systems
for the process industry sector –
Part 1:
Framework, definitions, system,
hardware and software requirements
Sécurité fonctionnelle –
Systèmes instrumentés de sécurité pour le secteur
des industries de transformation –
Partie 1:
Cadre, définitions et prescriptions concernant
le système,
le matériel et le logiciel
Reference number
Publication numbering
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INTERNATIONAL IEC
STANDARD
61511-1
First edition
2003-01
Functional safety –
Safety instrumented systems
for the process industry sector –
Part 1:
Framework, definitions, system,
hardware and software requirements
Sécurité fonctionnelle –
Systèmes instrumentés de sécurité pour le secteur
des industries de transformation –
Partie 1:
Cadre, définitions et prescriptions concernant
le système,
le matériel et le logiciel
 IEC 2003  Copyright - all rights reserved
No part of this publication may be reproduced or utilized in any form or by any means, electronic or
mechanical, including photocopying and microfilm, without permission in writing from the publisher.
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For price, see current catalogue

– 2 – 61511-1  IEC:2003(E)
CONTENTS
FOREWORD . 5
INTRODUCTION .7
1 Scope . 9
2 Normative references.14
3 Abbreviations and definitions .15
3.1 Abbreviations.15
3.2 Definitions .16
4 Conformance to this International Standard .30
5 Management of functional safety.30
5.1 Objective .30
5.2 Requirements .30
6 Safety life-cycle requirements .35
6.1 Objective .35
6.2 Requirements .35
7 Verification .37
7.1 Objective .37
8 Process hazard and risk analysis.38
8.1 Objectives .38
8.2 Requirements .38
9 Allocation of safety functions to protection layers.39
9.1 Objective .39
9.2 Requirements of the allocation process .39
9.3 Additional requirements for safety integrity level 4 .40
9.4 Requirements on the basic process control system as a protection layer .41
9.5 Requirements for preventing common cause, common mode and dependent
failures .42
10 SIS safety requirements specification .43
10.1 Objective .43
10.2 General requirements .43
10.3 SIS safety requirements.43
11 SIS design and engineering .44
11.1 Objective .44
11.2 General requirements .44
11.3 Requirements for system behaviour on detection of a fault .46
11.4 Requirements for hardware fault tolerance.47
11.5 Requirements for selection of components and subsystems .48
11.6 Field devices .51
11.7 Interfaces .52
11.8 Maintenance or testing design requirements .54
11.9 SIF probability of failure.54

61511-1  IEC:2003(E) – 3 –
12 Requirements for application software, including selection criteria for utility software .55
12.1 Application software safety life-cycle requirements .56
12.2 Application software safety requirements specification.62
12.3 Application software safety validation planning .64
12.4 Application software design and development.64
12.5 Integration of the application software with the SIS subsystem .69
12.6 FPL and LVL software modification procedures .70
12.7 Application software verification.70
13 Factory acceptance testing (FAT) .71
13.1 Objectives .72
13.2 Recommendations .72
14 SIS installation and commissioning.73
14.1 Objectives .73
14.2 Requirements .73
15 SIS safety validation .74
15.1 Objective .74
15.2 Requirements .74
16 SIS operation and maintenance .76
16.1 Objectives .76
16.2 Requirements .77
16.3 Proof testing and inspection.78
17 SIS modification.79
17.1 Objective .79
17.2 Requirements .79
18 SIS decommissioning.80
18.1 Objectives .80
18.2 Requirements .80
19 Information and documentation requirements.81
19.1 Objectives .81
19.2 Requirements .81
Annex A (informative) Differences .83
Figure 1 – Overall framework of this standard . 8
Figure 2 – Relationship between IEC 61511 and IEC 61508.11
Figure 3 – Relationship between IEC 61511 and IEC 61508 (see 1.2) .12
Figure 4 – Relationship between safety instrumented functions and other functions .13
Figure 5 – Relationship between system, hardware, and software of IEC 61511-1.14
Figure 6 – Programmable electronic system (PES): structure and terminology .23
Figure 7 – Example SIS architecture .26
Figure 8 – SIS safety life-cycle phases and functional safety assessment stages.33
Figure 9 – Typical risk reduction methods found in process plants .42
Figure 10 – Application software safety life cycle and its relationship to the SIS safety
life cycle.56

– 4 – 61511-1  IEC:2003(E)
Figure 11 – Application software safety life cycle (in realization phase).58
Figure 12 − Software development life cycle (the V-model) .59
Figure 13 – Relationship between the hardware and software architectures of SIS.62
Table 1 – Abbreviations used in IEC 61511 .15
Table 2 – SIS safety life-cycle overview .36
Table 3 – Safety integrity levels: probability of failure on demand .40
Table 4 – Safety integrity levels: frequency of dangerous failures of the SIF .40
Table 5 – Minimum hardware fault tolerance of PE logic solvers .47
Table 6 – Minimum hardware fault tolerance of sensors and final elements and non-PE
logic solvers.48
Table 7 – Application software safety life cycle: overview.60

61511-1  IEC:2003(E) – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
FUNCTIONAL SAFETY –
SAFETY INSTRUMENTED SYSTEMS
FOR THE PROCESS INDUSTRY SECTOR –
Part 1: Fr
...

IEC 61511-1
Edition 1.0 2003-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Functional safety – Safety instrumented systems for the process industry sector –
Part 1: Framework, definitions, system, hardware and software requirements

Sécurité fonctionnelle – Systèmes instrumentés de sécurité pour le secteur des
industries de transformation –
Partie 1: Cadre, définitions, exigences pour le système, le matériel et le logiciel

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IEC 61511-1
Edition 1.0 2003-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Functional safety – Safety instrumented systems for the process industry sector –
Part 1: Framework, definitions, system, hardware and software requirements

Sécurité fonctionnelle – Systèmes instrumentés de sécurité pour le secteur des
industries de transformation –
Partie 1: Cadre, définitions, exigences pour le système, le matériel et le logiciel

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
XC
CODE PRIX
ICS 25.040.01; 13.110 ISBN 2-8318-7316-9
61511-1 ¤ IEC:2003 –– 3 2 – – 61511-1 © IEC:2003
CONTENTS
FOREWORD.5
INTRODUCTION.7
1 Scope.10
2 Normative references.16
3 Abbreviations and definitions.16
3.1 Abbreviations .16
3.2 Definitions .17
4 Conformance to this International Standard .33
5 Management of functional safety .33
5.1 Objective.33
5.2 Requirements.33
6 Safety life-cycle requirements.38
6.1 Objective.38
6.2 Requirements.38
7 Verification.41
7.1 Objective.41
8 Process hazard and risk analysis .41
8.1 Objectives .41
8.2 Requirements.42
9 Allocation of safety functions to protection layers .43
9.1 Objective.43
9.2 Requirements of the allocation process .43
9.3 Additional requirements for safety integrity level 4.44
9.4 Requirements on the basic process control system as a protection layer.45
9.5 Requirements for preventing common cause, common mode and dependent
failures .46
10 SIS safety requirements specification .46
10.1 Objective.46
10.2 General requirements.46
10.3 SISsafetyrequirements .46
11 SIS design and engineering.48
11.1 Objective.48
11.2 General requirements.48
11.3 Requirements for system behaviour on detection of a fault .48
11.4 Requirements for hardware fault tolerance .51
11.5 Requirements for selection of components and subsystems .52
11.6 Field devices .56
11.7 Interfaces .56
11.8 Maintenance or testing design requirements.58
11.9 SIF probability of failure .59

61511-1 © IEC:200361511-1 ¤ IEC:2003 –– 5 3 – –
12 Requirements for application software, including selection criteria for utility software . .60
12.1 Application software safety life-cycle requirements.60
12.2 Application software safety requirements specification .66
12.3 Application software safety validation planning.68
12.4 Application software design and development .68
12.5 Integration of the application software with the SIS subsystem .74
12.6 FPL and LVL software modification procedures .75
12.7 Application software verification .75
13 Factory acceptance testing (FAT) .76
13.1 Objectives .76
13.2 Recommendations.77
14 SIS installation and commissioning.78
14.1 Objectives .78
14.2 Requirements.78
15 SISsafetyvalidation.79
15.1 Objective.79
15.2 Requirements.79
16 SIS operation and maintenance.82
16.1 Objectives .82
16.2 Requirements.82
16.3 Proof testing and inspection .84
17 SISmodification .8 5
17.1 Objective.85
17.2 Requirements.85
18 SISdecommissioning.86
18.1 Objectives .86
18.2 Requirements.86
19 Information and documentation requirements .86
19.1 Objectives .86
19.2 Requirements.87
Annex A (informative) Differences.88
Bibliography.89
Figure 1 – Overall framework of this standard.9
Figure 2 – Relationship between IEC 61511 and IEC 61508 .12
Figure 3 – Relationship between IEC 61511 and IEC 61508 (see 1.2).13
Figure 4 – Relationship between safety instrumente
...