EN 60079-29-3:2014

Explosive atmospheres - Part 29-3: Gas detectors - Guidance on functional safety of fixed gas detection systems

IEC 60079-29-3:2014 gives guidance for the design and implementation of a fixed gas detection system, including associated and/or peripheral gas detection equipment, for the detection of flammable gases/vapours and oxygen when used in a safety-related application in accordance with IEC 61508 and IEC 61511. This International standard also applies to the detection of toxic gases. Other parts of this international standard and pertinent local, national and international standards separately specify the performance requirements of a gas detector and a gas detection control unit (logic solver). These standards are commonly known as Metrological Performance Standards and are concerned with the accuracy of the measured value, the overall system performance, but not the device or system integrity with respect to the safety function. This international standard applies to the integrity of the safety function. Keywords: fixed gas detection system, flammable gases/vapours and Oxygen, detection of toxic gases

Explosionsfähige Atmosphäre - Teil 29-3: Gasmessgeräte - Leitfaden zur funktionalen Sicherheit von ortsfesten Gaswarnsystemen

Atmosphères explosives - Partie 29-3: Détecteurs de gaz - Recommandations relatives à la sécurité fonctionnelle des systèmes fixes de détection de gaz

L'IEC 60079-29-3:2014 donne des recommandations sur la conception et la mise en oeuvre d'un système fixe de détection de gaz, comprenant des équipements associés et/ou périphériques de détection de gaz, permettant de détecter des gaz/vapeurs inflammables et de l'oxygène dans le cadre d'une application relative à la sécurité conformément à l'IEC 61508 et à l'IEC 61511. La présente Norme internationale s'applique aussi à la détection des gaz toxiques. Les autres parties de la présente Norme internationale et les normes locales, nationales et internationales pertinentes spécifient séparément les exigences de performance d'un détecteur de gaz et d'une unité de commande de détection de gaz (unité logique). Ces normes sont généralement appelées Normes de Performances Métrologiques et traitent de la précision de la valeur mesurée, des performances globales du système, mais pas de l'intégrité du dispositif ou du système par rapport à la fonction de sécurité. La présente Norme internationale s'applique à l'intégrité de la fonction de sécurité. Mots clés: système fixe de détection de gaz, gaz/vapeurs inflammables et de l'oxygène, détection des gaz toxiques

Eksplozivne atmosfere - 29-3. del: Plinski detektorji - Navodilo o funkcijski varnosti fiksnih sistemov za odkrivanje plina (IEC 60079-29-3:2014)

Standard EN IEC 60079-29-3 zagotavlja smernice za načrtovanje in izvajanje fiksnih sistemov za odkrivanje plina, vključno z dodatno in/ali periferno opremo za odkrivanje plina, za odkrivanje vnetljivih plinov/hlapov in kisika pri uporabi v varnostnih pripravah v skladu s standardoma IEC 61508 in IEC 61511. Ta mednarodni standard se uporablja tudi za odkrivanje strupenih plinov. Drugi deli tega mednarodnega standarda in ustrezni lokalni, nacionalni in mednarodni standardi ločeno določajo zahteve glede zmogljivosti detektorja plina in nadzorne enote za odkrivanje plina (logic solver). Ti standardi so znani kot standardi meroslovnega delovanja ter obravnavajo točnost izmerjenih vrednosti in splošno delovanje sistema, ne pa celovite varnostne funkcije naprave ali sistema. Ta mednarodni standard se uporablja za integriteto varnostne funkcije. Ta mednarodni standard določa z varnostjo povezane dejavnike fiksnih sistemov za odkrivanje plina, vključno z dodatno in/ali periferno opremo za odkrivanje plina, z vidika ogrodja in filozofije standarda IEC 61508 in uvaja določene zahteve, ki jih zahteva sistem za odkrivanje plina na sliki 2. Ta mednarodni standard ne obravnava stopnje 4 integritete varnostnega sistema (SIL). Predpostavlja se, da integritete varnostnega sistema stopnje 4 pri sistemih za odkrivanje plina ni mogoče doseči. Ta mednarodni standard velja za fiksne sisteme za odkrivanje plina, ki jih lahko sestavljajo naslednje funkcijske enote strojne opreme: – senzor plina/oddajnik, – nadzorna enota za odkrivanje plina (logic solver), – vzorčenje plina (enojni tok in multipleksirani tokovi), – kondicioniranje plinov, – samodejna kalibracija in prilagajanje plinov, – izhodni modul (če ni del nadzorne enote).

General Information

• Status: Published
• Publication Date: 19-Jun-2014
• Withdrawal Date: 30-Apr-2017
• ICS: 29.260.20 - Electrical apparatus for explosive atmospheres
• Technical Committee: CLC/TC 31 - Electrical apparatus for explosive atmospheres - General requirements
• Drafting Committee: CLC/SC 31-9 - Electrical apparatus for the detection and measurement of combustible gases to be used in industrial
• Current Stage: 6060 - Document made available - Publishing
• Start Date: 20-Jun-2014
• Completion Date: 20-Jun-2014
• Directive: 94/9/EC - Directive 94/9/EC of the European Parliament and the Council of 23 March 1994 on the approximation of the laws of the Member States concerning equipment and protective systems intended for use in potentially explosive atmospheres
• Ref Project: SIST EN 60079-29-3:2014 - Explosive atmospheres - Part 29-3: Gas detectors - Guidance on functional safety of fixed gas detection systems ( IEC 60079-29-3:2014)

Standards Content (Sample)

SLOVENSKI STANDARD
01-november-2014
Eksplozivne atmosfere - 29-3. del: Plinski detektorji - Navodilo o funkcijski varnosti
fiksnih sistemov za odkrivanje plina (IEC 60079-29-3:2014)
Explosive atmospheres - Part 29-3: Gas detectors - Guidance on functional safety of
fixed gas detection systems ( IEC 60079-29-3:2014)
Explosionsfähige Atmosphäre - Teil 29-3: Gasmessgeräte - Leitfaden zur funktionalen
Sicherheit von ortsfesten Gaswarnsystemen (IEC 60079-29-3:2014)
Atmosphères explosives - Partie 29-3: Détecteurs de gaz - Recommandations relatives à
la sécurité fonctionnelle des systèmes fixes de détection de gaz (CIE 60079-29-3:2014)
Ta slovenski standard je istoveten z: EN 60079-29-3:2014
ICS:
13.230 Varstvo pred eksplozijo Explosion protection
13.320 Alarmni in opozorilni sistemi Alarm and warning systems
29.260.20 (OHNWULþQLDSDUDWL]D Electrical apparatus for
HNVSOR]LYQDR]UDþMD explosive atmospheres
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN 60079-29-3

NORME EUROPÉENNE
EUROPÄISCHE NORM
June 2014
ICS 29.260.20
English Version
Explosive atmospheres - Part 29-3: Gas detectors - Guidance on
functional safety of fixed gas detection systems
(IEC 60079-29-3:2014)
Atmosphères explosives - Partie 29-3: Détecteurs de gaz - Explosionsfähige Atmosphäre - Teil 29-3: Gasmessgeräte -
Recommandations relatives à la sécurité fonctionnelle des Leitfaden zur funktionalen Sicherheit von ortsfesten
systèmes fixes de détection de gaz Gaswarnsystemen
(CEI 60079-29-3:2014) (IEC 60079-29-3:2014)
This European Standard was approved by CENELEC on 2014-05-01. 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, 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
© 2014 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN 60079-29-3:2014 E
Foreword
The text of document 31/1105A/FDIS, future edition 1 of IEC 60079-29-3, prepared by IEC TC 31,
Equipment for explosive atmospheres, was submitted to the IEC-CENELEC parallel vote and approved
by CENELEC as EN 60079-29-3:2014.

The following dates are fixed:

(dop) 2015-02-01
• latest date by which the document has
to be implemented at national level by
publication of an identical national
standard or by endorsement
• latest date by which the national (dow) 2017-05-01
standards conflicting with the
document have to be withdrawn
This part of IEC 60079-29 is to be used in conjunction with the following standards:

– IEC 60079-0, Explosive atmospheres – Part 0: Equipment – General requirements
– IEC 60079-29-1, Explosive atmospheres – Part 29-1: Gas detectors – Performance
requirements of detectors for flammable gases
– IEC 60079-29-2, Explosive atmospheres – Part 29-2: Gas detectors – Selection,
installation, use and maintenance of detectors for flammable gases and oxygen
– IEC 60079-29-4, Explosive atmospheres – Part 29-4: Gas detectors – Performance requirements of
open path detectors for flammable gases
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 60079-29-3:2014 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 60079-1 NOTE Harmonised as EN 60079-10-1.
IEC 61511-1 NOTE Harmonised as EN 61511-1.
IEC 61511-2 NOTE Harmonised as EN 61511-2.
IEC 61511-3 NOTE Harmonised as EN 61511-3.

- 3 - EN 60079-29-3:2014
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 60079-29-1 -  Explosive atmospheres -- Part 29-1: Gas EN 60079-29-1 -
(mod) detectors - Performance requirements of
detectors for flammable gases
+AA
IEC 60079-29-2 2007 Explosive atmospheres -- Part 29-2: Gas EN 60079-29-2 2007
detectors - Selection, installation, use and
maintenance of detectors for flammable
gases and oxygen
+EN 60079-29- 2007
2:2007/corrigendum
Dec. 2007
IEC 60079-29-4 -  Explosive atmospheres -- Part 29-4: Gas EN 60079-29-4 -
(mod) detectors - Performance requirements of
open path detectors for flammable gases
+AA
IEC 61508 series Functional safety of EN 61508 series
electrical/electronic/programmable electronic
safety-related systems
IEC 60079-29-3 ®
Edition 1.0 2014-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Explosive atmospheres –
Part 29-3: Gas detectors – Guidance on functional safety of fixed gas detection

systems
Atmosphères explosives –
Partie 29-3: Détecteurs de gaz – Recommandations relatives à la sécurité

fonctionnelle des systèmes fixes de détection de gaz

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX X
ICS 29.260.20 ISBN 978-2-8322-1496-1

– 2 – IEC 60079-29-3:2014 © IEC 2014
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 10
2 Normative references . 11
3 Terms and definitions . 11
4 Requirements . 13
4.1 General . 13
4.2 Demand rate . 13
5 Gas detection unique features . 13
5.1 Objective . 13
5.2 Features . 14
5.2.1 General . 14
5.2.2 Sensor location . 14
5.2.3 Sensor filter elements (passive) . 14
5.2.4 Sensor filter elements (active) . 14
5.2.5 Sensor principles . 14
5.2.6 Poisoning and adverse chemical reaction . 15
5.2.7 ppm.hr or %vol.hr lifetime . 15
5.2.8 Negative gas readings . 15
5.2.9 Hazard and risk analysis . 15
5.2.10 Preventative effectiveness or mitigation effectiveness . 16
5.2.11 Cross sensitivities . 16
5.2.12 Special states . 16
5.2.13 Metrological performance standards . 16
5.2.14 Fault signal handling . 16
5.2.15 Over-range indication . 16
5.2.16 Surrogate calibration . 16
5.2.17 Maximum/minimum alarm set points . 17
6 Functional safety management . 17
6.1 Objective . 17
6.2 Requirements . 17
6.3 Competence . 18
7 General requirements . 19
7.1 Objective . 19
7.2 Requirements . 19
7.2.1 General . 19
7.2.2 Safety and non safety functions . 19
7.2.3 Safety functions of different integrity targets . 19
7.2.4 Behaviour under dangerous failure conditions. 19
7.2.5 Behaviour under safe failure conditions . 20
7.2.6 Behaviour under special state conditions . 20
7.2.7 Power supply . 21
7.2.8 Gas detector . 21
7.2.9 Gas detection control unit (logic solver) . 21
7.2.10 Final element (actuator) . 22
7.2.11 Visual indication . 22

IEC 60079-29-3:2014 © IEC 2014 – 3 –
7.2.12 Switching outputs . 22
7.2.13 Protocol outputs . 24
7.2.14 Protocol inputs . 24
7.2.15 System architecture, PFD and PFH values . 24
8 Gas detection unique requirements . 24
8.1 Objectives . 24
8.2 Requirements . 25
8.2.1 Introduction to gas sampling . 25
8.2.2 Gas sampling. 25
8.2.3 Gas multiplexer . 26
8.2.4 Gas multiplexer control system . 27
8.2.5 Conditioning of measured gas . 27
8.2.6 Gas sampling by diffusion mode . 28
8.2.7 Automatic calibration and adjustment. 28
8.2.8 Automatic calibration and adjustment control system . 29
9 Alternative control units (logic solvers) .
...