SIST EN 61511-2:2017

Functional safety - Safety instrumented systems for the process industry sector - Part 2: Guidelines for the application of IEC 61511-1 (IEC 61511-2:2016)

This part of IEC 61511 provides guidance on the specification, design, installation, operation
and maintenance of SIFs and related SIS as defined in IEC 61511-1:2016.
NOTE 1 Annex A (informative) has been organized so that each clause and subclause number therein addresses
the corresponding clause and subclause number in IEC 61511-1:2016 except for being preceded by “A”.
NOTE 2 Annex A now contains material previously in the body of the first edition. These changes are required for
compliance with IEC rules which prohibit a standard being wholly informative.
NOTE 3 To achieve maximum use of this guideline;
– review the section guidance as well as the specific clause guidance. (e.g., when looking for guidance on
5.2.6.1.3, consider guidance in 5.2.6);
– when specific clause guidance is not provided (e.g.; no further guidance provided), consider reviewing the
section guidance as well, as it can be applicable).
NOTE 4 Examples given in the Annexes of this Standard are intended only as case specific examples of
implementing IEC 61511 requirements in a specific instance, and the user should satisfy themselves that the
chosen methods and techniques are appropriate to their situation.

Funktionale Sicherheit - PLT-Sicherheitseinrichtungen für die Prozessindustrie - Teil 2: Anleitungen zur Anwendung des Teils 1 (IEC 61511-2:2016)

Sécurité fonctionnelle - Systèmes instrumentés de sécurité pour le secteur des industries de transformation - Partie 2: Directives pour l’application de l’IEC 61511-1 (IEC 61511-2:2016)

L'IEC 61511-2 :2016 donne les lignes directrices relatives à la spécification, la conception, l'installation, au fonctionnement et à la maintenance des SIF et des SIS associés, telles que définies dans l'IEC 61511-1:2016. Cette deuxième édition annule et remplace la première édition parue en 2003. Cette édition constitue une révision technique. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente: description des exemples d'orientation, basés sur toutes les phases du cycle de vie de sécurité,  réalisée avec des exemples basés sur l'expérience de l'utilisation de la norme IEC 61511 première édition; remplacement des annexes pour répondre à la transition de logiciel à programmation d'application.

Funkcijska varnost - Sistemi z varnostnimi instrumenti za sektor procesne industrije - 2. del: Smernice za uporabo IEC 61511-1 (IEC 61511-2:2016)

Ta del standarda IEC 61511 določa zahteve za specifikacijo, zasnovo, namestitev, delovanje in vzdrževanje funkcij z varnostnimi instrumenti in povezanimi sistemi z varnostnimi instrumenti, kot je določeno v standardu IEC 61511-1:2016.
OPOMBA 1: Dodatek A (informativni) je bil organiziran na način, da vsaka številka točke in podtočke obravnava ustrezno številko točke in podtočke v standardu IEC 61511-1:2016, s to razliko, da pred njimi stoji »A«.
OPOMBA 2: Dodatek A zdaj vsebuje material, ki je bil prej v besedilu prve izdaje. Te spremembe so potrebne zaradi skladnosti s pravili IEC, ki prepovedujejo, da bi bil standard v celoti informativen.
OPOMBA 3: Da bi lahko v kar največji meri uporabili te smernice:
– si oglejte napotke za razdelke in posamezne točke (npr. ko iščete napotke za 5.2.6.1.3, upoštevajte napotke v točki 5.2.6);
– kadar ni na voljo napotkov za določeno točko (npr. ni dodatnih napotkov), si oglejte tudi napotke za razdelek, saj so lahko uporabni).
OPOMBA 4: Primeri, navedeni v dodatkih tega standarda, se navezujejo na posamezne primere uporabe zahtev iz standarda IEC 61511 v določenem primeru, uporabnik pa se mora prepričati, da so izbrane metode in tehnike primerne v njegovem primeru.

General Information

• Status: Published
• Publication Date: 07-Aug-2017
• ICS: 25.040.40 - Industrial process measurement and control
• Technical Committee: MOV - Measuring equipment for electromagnetic quantities
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 08-May-2017
• Due Date: 13-Jul-2017
• Completion Date: 08-Aug-2017
• Ref Project: EN 61511-2:2017 - Functional safety - Safety instrumented systems for the process industry sector - Part 2: Guidelines for the application of IEC 61511-1

Relations

• Replaces: SIST EN 61511-2:2007 - Functional safety - Safety instrumented systems for the process industry sector -- Part 2: Guidelines for the application of IEC 61511-1
• Effective Date: 22-Apr-2014
• Replaces: SIST EN 61511-2:2007 - Functional safety - Safety instrumented systems for the process industry sector -- Part 2: Guidelines for the application of IEC 61511-1
• Effective Date: 29-Jan-2023
• Replaces: SIST EN 61511-2:2007 - Functional safety - Safety instrumented systems for the process industry sector -- Part 2: Guidelines for the application of IEC 61511-1
• Effective Date: 07-Jun-2022

Standards Content (Sample)

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Funkcijska varnost - Sistemi z varnostnimi instrumenti za sektor procesne industrije - 2. del: Smernice za uporabo IEC 61511-1 (IEC 61511-2:2016)Funktionale Sicherheit - PLT-Sicherheitseinrichtungen für die Prozessindustrie - Teil 2: Anleitungen zur Anwendung des Teils 1 (IEC 61511-2:2016)Sécurité fonctionnelle - Systèmes instrumentés de sécurité pour le secteur des industries de transformation - Partie 2: Directives pour l’application de l’IEC 61511-1 (IEC 61511-2:2016)Functional safety - Safety instrumented systems for the process industry sector - Part 2: Guidelines for the application of IEC 61511-1 (IEC 61511-2:2016)25.040.40Merjenje in krmiljenje industrijskih postopkovIndustrial process measurement and controlICS:Ta slovenski standard je istoveten z:EN 61511-2:2017SIST EN 61511-2:2017en,fr,de01-september-2017SIST EN 61511-2:2017SLOVENSKI
STANDARDSIST EN 61511-2:20071DGRPHãþD



SIST EN 61511-2:2017



EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM
EN 61511-2
April 2017 ICS 13.110; 25.040.01
Supersedes
EN 61511-2:2004
English Version
Functional safety - Safety instrumented systems for the process industry sector - Part 2: Guidelines for the application of IEC 61511-1 (IEC 61511-2:2016)
Sécurité fonctionnelle - Systèmes instrumentés de sécurité pour le secteur des industries de transformation - Partie 2: Lignes directives pour l'application de l'IEC 61511-1 (IEC 61511-2:2016)
Funktionale Sicherheit - PLT-Sicherheitseinrichtungen für die Prozessindustrie - Teil 2: Anleitungen zur Anwendung des Teils 1 (IEC 61511-2:2016) This European Standard was approved by CENELEC on 2016-09-01. 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 CEN-CENELEC Management Centre 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 CEN-CENELEC Management Centre has the same status as the official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique Europäisches Komitee für Elektrotechnische Normung CEN-CENELEC Management Centre: Avenue Marnix 17,
B-1000 Brussels © 2017 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN 61511-2:2017 E SIST EN 61511-2:2017



EN 61511-2:2017 2 European foreword The text of document 65A/783/FDIS, future edition 2 of IEC 61511-2, prepared by SC 65A “System aspects” of IEC/TC 65 “Industrial process measurement, control and automation" was submitted to the IEC-CENELEC parallel vote and approved by CENELEC as EN 61511-2:2017.
The following dates are fixed: • latest date by which the document has to be implemented at national level by publication of an identical national standard or by endorsement (dop) 2017-10-21 • latest date by which the national standards conflicting with the document have to be withdrawn (dow) 2020-04-21
This document supersedes EN 61511-2:2004.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CENELEC [and/or CEN] shall not be held responsible for identifying any or all such patent rights.
Endorsement notice The text of the International Standard IEC 61511-2:2016 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 60880:2006 NOTE Harmonized as EN 60880:2009. IEC 61025:2006 NOTE Harmonized as EN 61025:2007. IEC 61078:2006 NOTE Harmonized as EN 61078:2006. IEC 61131-3:2013 NOTE Harmonized as EN 61131-3:2013. IEC 61165:2006 NOTE Harmonized as EN 61165:2006. IEC 61508-1:2010 NOTE Harmonized as EN 61508-1:2010. IEC 61508-2:2010 NOTE Harmonized as EN 61508-2:2010. IEC 61508-3:2010 NOTE Harmonized as EN 61508-3:2010. IEC 61508-6:2010 NOTE Harmonized as EN 61508-6:2010. IEC 61508-6:2010 NOTE Harmonized as EN 61508-6:2010. IEC 62061:2005 NOTE Harmonized as EN 62061:2005. IEC 62502:2010 NOTE Harmonized as EN 62502:2010. IEC 62551:2012 NOTE Harmonized as EN 62551:2012. ISO 9000:2015 NOTE Harmonized as EN ISO 9000:2015. SIST EN 61511-2:2017



EN 61511-2:2017 3 ISO 10418:2003 NOTE Harmonized as EN ISO 10418:2003. ISO/TR 12489:2013 NOTE Harmonized as CEN ISO/TR 12489:2016. ISO 17776:2000 NOTE Harmonized as EN ISO 17776:2002.
SIST EN 61511-2:2017



EN 61511-2:2017 4
Annex ZA (normative)
Normative references to international publications with their corresponding European publications
The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
NOTE 1 When an International Publication has been modified by common modifications, indicated by (mod), the relevant EN/HD applies.
NOTE 2 Up-to-date information on the latest versions of the European Standards listed in this annex is available here: www.cenelec.eu.
Publication Year Title EN/HD Year IEC 61511-1 2016
Functional safety - Safety instrumented systems for the process industry sector - Normative (uon) -- Part 1: Framework, definitions, system, hardware and software requirements EN 61511-1 2016
SIST EN 61511-2:2017



IEC 61511-2 Edition 2.0 2016-07 INTERNATIONAL STANDARD NORME INTERNATIONALE Functional safety – Safety instrumented systems for the process industry
sector –
Part 2: Guidelines for the application of IEC 61511-1: 2016
Sécurité fonctionnelle – Systèmes instrumentés de sécurité pour le secteur
des industries de transformation –
Partie 2: Lignes directrices pour l'application de l'IEC 61511-1:2016
INTERNATIONAL ELECTROTECHNICAL COMMISSION COMMISSION ELECTROTECHNIQUE INTERNATIONALE
ICS 13.110; 25.040.01
ISBN 978-2-8322-3227-9
® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale ®
Warning! Make sure that you obtained this publication from an authorized distributor.
Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé. SIST EN 61511-2:2017 colourinside



– 2 – IEC 61511-2:2016 © IEC 2016 CONTENTS FOREWORD. 9 INTRODUCTION . 11 1 Scope . 13 2 Normative references . 13 3 Terms, definitions, and abbreviations . 13 Annex A (informative)
Guidance for IEC 61511-1 . 14 A.1 Scope . 14 A.2 Normative references . 14 A.3 Terms, definitions and abbreviations . 14 A.4 Conformance to the IEC 61511-1:– . 14 A.5 Management of functional safety . 14 A.5.1 Objective . 14 A.5.2 Guidance to "Requirements" . 14 A.6 Safety life-cycle requirements . 23 A.6.1 Objectives . 23 A.6.2 Guidance to "Requirements" . 23 A.6.3 Guidance to "Application program SIS safety life-cycle requirements" . 24 A.7 Verification . 25 A.7.1 Objective . 25 A.7.2 Guidance to "Requirements" . 25 A.8 Process hazard and risk assessment (H&RA) . 27 A.8.1 Objectives . 27 A.8.2 Guidance to “Requirements" . 27 A.9 Allocation of safety functions to protection layers . 30 A.9.1 Objective . 30 A.9.2 Guidance to "Requirements of the allocation process". 30 A.9.3 Guidance to "Requirements on the basic process control system as a protection layer" . 32 A.9.4 Guidance to "Requirements for preventing common cause, common mode and dependent failures" . 35 A.10 SIS safety requirements specification . 36 A.10.1 Objective . 36 A.10.2 Guidance to "General requirements" . 36 A.10.3 Guidance to "SIS safety requirements" . 36 A.11 SIS design and engineering . 40 A.11.1 Objective . 40 A.11.2 Guidance to "General requirements" . 40 A.11.3 Guidance to "Requirements for system behaviour on detection of a fault" . 47 A.11.4 Guidance to “Hardware fault tolerance" . 47 A.11.5 Guidance to "Requirements for selection of devices" . 50 A.11.6 Field devices . 53 A.11.7 Interfaces . 53 A.11.8 Guidance to "Maintenance or testing design requirements" . 55 A.11.9 Guidance to "Quantification of random failure" . 56 A.12 SIS application program development . 62 SIST EN 61511-2:2017



IEC 61511-2:2016 © IEC 2016 – 3 – A.12.1 Objective . 62 A.12.2 Guidance to "General requirements" . 62 A.12.3 Guidance to "Application program design" . 64 A.12.4 Guidance to "Application program implementation" . 66 A.12.5 Guidance to "Requirements for application program verification (review and testing)" . 67 A.12.6 Guidance to "Requirements for application program methodology and tools" . 70 A.13 Factory acceptance testing (FAT) . 73 A.13.1 Objectives . 73 A.13.2 Guidance to "Recommendations" . 73 A.14 SIS installation and commissioning . 73 A.14.1 Objectives . 73 A.14.2 Guidance to "Requirements" . 73 A.15 SIS safety validation . 74 A.15.1 Objective . 74 A.15.2 Guidance to "Requirements" . 74 A.16 SIS operation and maintenance . 74 A.16.1 Objectives . 74 A.16.2 Guidance to "Requirements" . 75 A.16.3 Proof testing and inspection . 76 A.17 SIS modification . 78 A.17.1 Objective . 78 A.17.2 Guidance to "Requirements" . 79 A.18 SIS decommissioning . 79 A.18.1 Objectives . 79 A.18.2 Guidance to "Requirements" . 79 A.19 Information and documentation requirements . 80 A.19.1 Objectives . 80 A.19.2 Guidance to "Requirements" . 80 Annex B (informative)
Example of SIS logic solver application program development using function block diagram . 81 B.1 General . 81 B.2 Application program development and validation philosophy . 81 B.3 Application description . 82 B.3.1 General . 82 B.3.2 Process description . 82 B.3.3 Safety instrumented functions . 83 B.3.4 Risk reduction and domino effects . 84 B.4 Application program safety life-cycle execution . 84 B.4.1 General . 84 B.4.2 Inputs to application program SRS development . 84 B.4.3 Application program design and development . 87 B.4.4 Application program production . 101 B.4.5 Application program verification and testing . 101 B.4.6 Validation . 101 Annex C (informative)
Considerations when converting from NP technologies to PE technologies . 102 SIST EN 61511-2:2017



– 4 – IEC 61511-2:2016 © IEC 2016 Annex D (informative)
Example of how to get from a piping
and instrumentation diagram (P&ID) to application program . 104 Annex E (informative)
Methods and tools for application programming . 107 E.1 Typical toolset for application programming . 107 E.2 Rules and constraints for application program design . 108 E.3 Rules and constraints for application programming . 108 Annex F (informative)
Example SIS project illustrating each phase of the safety life cycle with application program development using relay ladder language . 110 F.1 Overview . 110 F.2 Project definition . 110 F.2.1 General . 110 F.2.2 Conceptual planning . 111 F.2.3 Process hazards analysis . 111 F.3 Simplified process description . 111 F.4 Preliminary design . 113 F.5 IEC 61511 application . 113 F.5.1 General . 113 F.5.2 Step F.1: Hazard & risk assessment . 117 F.5.3 Hazard identification . 117 F.5.4 Preliminary hazard evaluation . 117 F.5.5 Accident history . 117 F.6 Preliminary process design safety considerations . 120 F.7 Recognized process hazards . 120 F.8 Process design definitions strategy . 121 F.9 Preliminary hazard assessment . 124 F.9.1 General . 124 F.9.2 Step F.2: Allocation of safety functions . 128 F.10 SIF safety integrity level determination . 129 F.11 Layer of protection analysis (LOPA) applied to example . 129 F.12 Tolerable risk criteria . 130 F.13 Step F.3: SIS safety requirements specifications . 133 F.13.1 Overview . 133 F.13.2 Input requirements . 133 F.13.3 Safety functional requirements . 134 F.13.4 Safety integrity requirements . 135 F.14 Functional description and conceptual design . 136 F.14.1 Narrative for example reactor system logic . 136 F.15 SIL verification calculations . 137 F.16 Application program requirements . 144 F.17 Step F.4:
SIS safety life-cycle . 151 F.18 Technology and device selection . 151 F.18.1 General . 151 F.18.2 Logic solver . 151 F.18.3 Sensors . 152 F.18.4 Final elements . 152 F.18.5 Solenoid valves . 152 F.18.6 Emergency vent valves . 153 F.18.7 Modulating valves . 153 F.18.8 Bypass valves . 153 SIST EN 61511-2:2017



IEC 61511-2:2016 © IEC 2016 – 5 – F.18.9 Human-machine interfaces (HMIs) . 153 F.18.10 Separation . 154 F.19 Common cause and systematic failures . 155 F.19.1 General . 155 F.19.2 Diversity . 155 F.19.3 Specification errors . 155 F.19.4 Hardware design errors . 155 F.19.5 Software design errors . 156 F.19.6 Environmental overstress . 156 F.19.7 Temperature . 156 F.19.8 Humidity . 156 F.19.9 Contaminants . 157 F.19.10 Vibration . 157 F.19.11 Grounding . 157 F.19.12 Power line conditioning . 157 F.19.13 Electro-magnetic compatibility (EMC) . 157 F.19.14 Utility sources . 158 F.19.15 Sensors . 159 F.19.16 Process corrosion or fouling . 159 F.19.17 Maintenance . 159 F.19.18 Susceptibility to mis-operation . 159 F.19.19 SIS architecture . 159 F.20 SIS application program design features . 160 F.21 Wiring practices . 161 F.22 Security . 161 F.23 Step F.5: SIS installation, commissioning, validation . 162 F.24 Installation . 162 F.25 Commissioning . 163 F.26 Documentation . 164 F.27 Validation . 164 F.28 Testing . 165 F.29 Step F.6:
SIS operation and maintenance . 178 F.30 Step F.7:
SIS Modification . 181 F.31 Step F.8: SIS decommissioning . 181 F.32 Step F.9: SIS verification . 181 F.33 Step F.10: Management of functional safety and SIS FSA . 182 F.34 Management of functional safety . 183 F.34.1 General . 183 F.34.2 Competence of personnel . 183 F.35 Functional safety assessment . 183 Annex G (informative)
Guidance on developing application programming practices . 184 G.1 Purpose of this guidance . 184 G.2 Generic safe application programming attributes . 184 G.3 Reliability . 184 G.3.1 General . 184 G.3.2 Predictability of memory utilisation . 185 G.3.3 Predictability of control flow . 186 G.3.4 Accounting for precision and accuracy . 188 G.3.5 Predictability of timing . 190 SIST EN 61511-2:2017



– 6 – IEC 61511-2:2016 © IEC 2016 G.4 Predictability of mathematical or logical result . 190 G.5 Robustness . 191 G.5.1 General . 191 G.5.2 Controlling use of diversity . 191 G.5.3 Controlling use of exception handling . 192 G.5.4 Checking input and output . 193 G.6 Traceability . 194 G.6.1 General . 194 G.6
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