EN 60079-14:2008

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Explosionsfähige Atmosphäre -- Teil 14: Projektierung, Auswahl und Errichtung elektrischer AnlagenAtmosphères explosives -- Partie 14: Conception, sélection et construction des installations électriquesExplosive atmospheres -- Part 14: Electrical installations design, selection and erection91.140.50Sistemi za oskrbo z elektrikoElectricity supply systems29.260.20Electrical apparatus for explosive atmospheresICS:Ta slovenski standard je istoveten z:EN 60079-14:2008SIST EN 60079-14:2009en,fr,de01-januar-2009SIST EN 60079-14:2009SLOVENSKI
STANDARDSIST EN 61241-14:2005SIST EN 60079-14:20031DGRPHãþD

EUROPEAN STANDARD EN 60079-14 NORME EUROPÉENNE
EUROPÄISCHE NORM October 2008
CENELEC European Committee for Electrotechnical Standardization Comité Européen de Normalisation Electrotechnique Europäisches Komitee für Elektrotechnische Normung
Central Secretariat: rue de Stassart 35, B - 1050 Brussels
© 2008 CENELEC -
All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 60079-14:2008 E
ICS 29.260.20 Supersedes EN 60079-14:2003
English version
Explosive atmospheres -
Part 14: Electrical installations design,
selection and erection (IEC 60079-14:2007)
Atmosphères explosives -
Partie 14: Conception,
sélection et construction
des installations électriques (CEI 60079-14:2007)
Explosionsfähige Atmosphäre -
Teil 14: Projektierung,
Auswahl und Errichtung
elektrischer Anlagen (IEC 60079-14:2007)
This European Standard was approved by CENELEC on 2008-07-01. 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 Central Secretariat 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 Central Secretariat has the same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom.
2008-07-01. This European Standard supersedes EN 60079-14:2003. It constitutes a technical revision with respect to gases and vapours and incorporates the requirements for dusts from EN 61241-14:2004. The incorporation of requirements for dust is without technical change. The significant technical changes with respect to EN 60079-14:2003 are as follows: – knowledge, skills and competencies of "Responsible Persons”, “Operatives" and "Designers" are explained in Annex F; – Equipment Protection Levels (EPLs) have been introduced and are explained in the new Annex I; – dust requirements included from EN 61241-14:2004. NOTE Dust requirements are included as an interim presentation for the purpose of EN 60079-14:2008 and will be refined in a next edition with other required technical changes. The following dates were fixed: – latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement
(dop)
2009-05-01 – latest date by which the national standards conflicting
with the EN have to be withdrawn
(dow)
2011-07-01 Annexes ZA and ZB have been added by CENELEC. __________ Endorsement notice The text of the International Standard IEC 60079-14:2007 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/TS 60034-17 NOTE Harmonized as CLC/TS 60034-17:2004 (not modified).IEC/TS 60034-25 NOTE Harmonized as CLC/TS 60034-25:2005 (not modified).IEC 60332-2-2 NOTE Harmonized as EN 60332-2-2:2004 (not modified) IEC 60742 NOTE Harmonized as EN 60742:1995 (modified).
Superseded by EN 61558 series (partially modified) IEC 61008-1 NOTE Harmonized as EN 61008-1:2004 (modified) IEC 61010-1 NOTE Harmonized as EN 61010-1:2001 (not modified) IEC 61024-1 NOTE Superseded by IEC 62305-3, which is harmonized as EN 62305-3:2006 (modified) __________
– 3 – EN 60079-14:2008
Annex ZA
(normative)
Normative references to international publications with their corresponding European publications
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
NOTE
When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD applies.
Publication Year Title EN/HD Year
IEC 60034-1 – 1) Rotating electrical machines -
Part 1: Rating and performance EN 60034-1 2004 2)
IEC 60034-5
– 1) Rotating electrical machines -
Part 5: Degrees of protection provided by the integral design of rotating electrical machines (IP code) - Classification EN 60034-5 2001 2)
IEC 60050-826 – 1) International Electrotechnical Vocabulary (IEV) -
Part 826: Electrical installations – –
IEC 60060-1 – 1) High-voltage test techniques - Part 1: General definitions and test requirements HD 588.1 S1 1991 2)
IEC 60079 Series Explosive atmospheres
EN 60079 Series
IEC 60079-0 (mod) – 1) Explosive atmospheres -
Part 0: Equipment – General requirements EN 60079-0 2006 2)
IEC 60079-1 – 1) Explosive atmospheres -
Part 1: Equipment protection by flameproof enclosures "d" EN 60079-1 2007 2)
IEC 60079-2 – 1) Explosive atmospheres -
Part 2: Equipment protection by pressurized enclosure "p"
EN 60079-2 2007 2)
IEC 60079-5 – 1) Explosive atmospheres -
Part 5: Equipment protection by powder filling "q" EN 60079-5 2007 2)
IEC 60079-6 – 1) Explosive atmospheres -
Part 6: Equipment protection by oil immersion "o" EN 60079-6 2007 2)
IEC 60079-7 – 1) Explosive atmospheres -
Part 7: Equipment protection by increased safety "e" EN 60079-7 2007 2)
IEC 60079-11
– 1) Explosive atmospheres -
Part 11: Equipment protection by intrinsic safety "i" EN 60079-11 2007 2)
IEC/TR 60079-13 – 1) Electrical apparatus for explosive gas atmospheres -
Part 13: Construction and use of rooms or buildings protected by pressurization – –
1) Undated reference.
2) Valid edition at date of issue.
IEC 60079-15 – 1) Electrical apparatus for explosive gas atmospheres -
Part 15: Construction, test and marking of type of protection "n" electrical apparatus EN 60079-15 2005 2)
IEC/TR 60079-16 – 1) Electrical apparatus for explosive gas atmospheres -
Part 16: Artificial ventilation for the protection of analyzer(s) houses – –
IEC 60079-18 – 1) Electrical apparatus for explosive gas atmospheres -
Part 18: Construction, test and marking of type of protection encapsulation "m" electrical apparatus EN 60079-18 + corr. April
2004 2)2006
IEC 60079-19 – 1) Explosive atmospheres -
Part 19: Equipment repair, overhaul and reclamation EN 60079-19 2007 2)
IEC 60079-25 – 1) Electrical apparatus for explosive gas atmospheres -
Part 25: Intrinsically safe systems EN 60079-25 + corr. April
2004 2)2006
IEC 60079-26 – 1) Explosive atmospheres -
Part 26: Equipment with equipment protection level (EPL) Ga EN 60079-26 2007 2)
IEC 60079-27 – 1) Explosive atmospheres -
Part 27: Fieldbus intrinsically safe concept (FISCO) EN 60079-27 2008 2)
IEC 60079-28 – 1) Explosive atmospheres - Part 28: Protection of equipment and transmission systems using optical radiation EN 60079-28 2007 2)
IEC 60079-29-1 (mod) – 1) Explosive atmospheres -
Part 29-1: Gas detectors - Performance requirements of detectors for flammable gases EN 60079-29-1 2007 2)
IEC 60079-29-2 – 1) Explosive atmospheres -
Part 29-2: Gas detectors - Selection, installation, use and maintenance of detectors for flammable gases and oxygen EN 60079-29-2 + corr. December
2007 2)2007
IEC 60079-31 – 3) Explosive Atmospheres -
Part 31: Equipment dust ignition protection by enclosure "tD" EN 60079-31 – 3)
IEC 60243-1 – 1) Electrical strength of insulating materials - Test methods -
Part 1: Tests at power frequencies EN 60243-1 1998 2)
IEC 60332-1-2 – 1) Tests on electric and optical fibre cables under fire conditions -
Part 1-2: Test for vertical flame propagation for a single insulated wire or cable - Procedure for 1 kW pre-mixed flame EN 60332-1-2 2004 2)
IEC 60364 (mod) Series Low-voltage electrical installations
HD 60364/ HD 384 Series
3) To be published.
– 5 – EN 60079-14:2008 Publication Year Title EN/HD Year
IEC 60364-4-41 (mod) – 1) Low-voltage electrical installations -
Part 4-41: Protection for safety - Protection against electric shock HD 60364-4-41 + corr. July
2007 2)2007
IEC 60529 – 1) Degrees of protection provided by
enclosures (IP Code) EN 60529 + corr. May
1991 2)1993
IEC 60950 (mod) Series Information technology equipment - Safety
EN 60950 Series
IEC 61010-1
– 1) Safety requirements for electrical equipment for measurement, control, and laboratory use - Part 1: General requirements EN 61010-1 + corr. June
2001 2)2002
IEC 61241 Series Electrical apparatus for use in the
presence of combustible dust
EN 61241
Series
IEC 61241-0 (mod)
– 1) Electrical apparatus for use in the presence of combustible dust -
Part 0: General requirements EN 61241-0 2006 2)
IEC 61241-1 – 1) Electrical apparatus for use in the
presence of combustible dust -
Part 1: Protection by enclosures "tD" EN 61241-1 + corr. December
2004 2)2006
IEC 61241-2-1 – 1) Electrical apparatus for use in the presence of combustible dust -
Part 2: Test methods -
Section 1: Methods for determining the minimum ignition temperatures of dust – –
IEC 61241-4 – 1) Electrical apparatus for use in the
presence of combustible dust -
Part 4: Type of protection 'pD' EN 61241-4 2006 2)
IEC 61241-10 – 1) Electrical apparatus for use in the presence of combustible dust -
Part 10: Classification of areas where combustible dusts are or may be present EN 61241-10 2004 2)
IEC 61241-11
– 1) Electrical apparatus for use in the
presence of combustible dust -
Part 11: Protection by intrinsic safety 'iD' EN 61241-11 2006 2)
IEC 61285 – 1) Industrial-process control - Safety of analyser houses EN 61285 2004 2)
IEC 61558-2-6 – 1) Safety of power transformers, power supply units and similar -
Part 2-6: Particular requirements for safety isolating transformers for general use EN 61558-2-6 1997 2)
IEC 62305-3 (mod) – 1) Protection against lightning -
Part 3: Physical damage to structures and life hazard EN 62305-3 + corr. September
2006 2)2008
ISO 10807 – 1) Pipework - Corrugated flexible metallic hose assemblies for the protection of electric cables in explosive atmospheres EN ISO 10807 1996 2)
ATEX Categories and Equipment Protection Levels (EPLs) This European Standard has been written to incorporate the concept of Equipment Protection Levels (EPLs). EPLs are analogous to the ATEX Categories, indeed the definitions are identical. Wherever there is a reference to an EPL in the text it should be equated with the corresponding ATEX Category: - EPL ‘Ga’ equates to ATEX Category 1G; - EPL ‘Gb’ equates to ATEX Category 2G; - EPL ‘Gc’ equates to ATEX Category 3G; - EPL ‘Da’ equates to ATEX Category 1D; - EPL ‘Db’ equates to ATEX Category 2D; - EPL ‘Dc’ equates to ATEX Category 3D.
IEC 60079-14Edition 4.0 2007-12INTERNATIONAL STANDARD NORME INTERNATIONALEExplosive atmospheres –
Part 14: Electrical installations design, selection and erection
Atmosphères explosives –
Partie 14: Conception, sélection et construction des installations électriques
INTERNATIONAL ELECTROTECHNICAL COMMISSION COMMISSION ELECTROTECHNIQUE INTERNATIONALE XDICS 29.260.20 PRICE CODECODE PRIXISBN 2-8318-9491-3
– 2 – 60079-14 © IEC:2007 CONTENTS FOREWORD.8 INTRODUCTION.10
1 Scope.13 2 Normative references.13 3 Terms and definitions.16 3.1 General.16 3.2 Hazardous areas.16 3.3 Flameproof enclosure.17 3.4 Increased safety.17 3.5 Intrinsic safety - General.18 3.6 Intrinsic safety parameters.19 3.7 Pressurization.19 3.8 Type of protection 'n'.19 3.13 Electrical supply systems.20 3.14 Equipment.21 4 General.21 4.1 General requirements.21 4.2 Documentation.22 4.3 Assurance of conformity of equipment.23 4.3.1 Equipment with certificates according to IEC standards.23 4.3.2 Equipment without certificates according to IEC standards.23 4.3.3 Selection of repaired, second hand or existing equipment.23 4.4 Qualifications of personnel.23 5 Selection of equipment (excluding cables and conduits).24 5.1 Information requirements.24 5.2 Zones.24 5.3 Relationship between Equipment protection levels (EPLs) and zones.24 5.4 Selection of equipment according to EPLs.25 5.4.1 Relationship between EPLs and types of protection.25 5.4.2 Equipment for use in locations requiring EPL 'Ga' or 'Da'.26 5.4.3 Equipment for use in locations requiring EPL ‘Gb’ or 'Db'.26 5.4.4 Equipment for use in locations requiring EPL ‘Gc’ or ‘Dc’.26 5.5 Selection according to equipment grouping.26 5.6 Selection according to the ignition temperature of the gas, vapour or dust and ambient temperature.27 5.6.1 General.27 5.6.2 Gas or Vapour.27 5.6.3 Dust.27 5.7 Selection of radiating equipment for dust.30 5.7.1 Ignition process.30 5.7.2 Safety measures in zone 20 or 21.30 5.7.3 Safety measures in zone 22.31 5.8 Selection of ultrasonic equipment for dust.31 5.8.1 Ignition process.31 5.8.2 Safety measures.31 SIST EN 60079-14:2009

60079-14 © IEC:2007 – 3 – 5.9 External influences.31 5.10 Light metals as construction materials.32 5.10.1 Gas or vapour.32 5.10.2 Dust.32 5.11 Transportable, Portable and Personal equipment.33 5.11.1 General.33 5.11.2 Transportable and Portable equipment - Gas.33 5.11.3 Personal Equipment - Gas.33 5.11.4 Dust.33 5.12 Selection of rotating electrical machines.34 5.12.1 General.34 5.12.2 Motors fed from a converter supply.34 5.13 Luminaires.34 5.14 Plugs and socket outlets for dust.34 5.14.1 General.34 5.14.2 Mounting.34 5.14.3 Location.35 6 Protection from dangerous (incendive) sparking.35 6.1 Danger from live parts.35 6.2 Danger from exposed and extraneous conductive parts.35 6.2.1 TN type of system earthing.35 6.2.2 TT type of system earthing.35 6.2.3 IT type of system earthing.35 6.2.4 SELV and PELV systems.35 6.2.5 Electrical separation.36 6.2.6 Above hazardous areas.36 6.3 Potential equalization.36 6.3.1 General.36 6.3.2 Temporary bonding.37 6.4 Static electricity.37 6.4.1 Gas.37 6.4.2 Dust.38 6.5 Lightning protection.38 6.6 Electromagnetic radiation.38 6.7 Cathodically protected metallic parts.38 6.8 Ignition by optical radiation.39 7 Electrical protection.39 7.1 General.39 7.2 Rotating electrical machines.39 7.3 Transformers.39 7.4 Resistance heating devices.40 8 Emergency switch-off and electrical isolation.40 8.1 Emergency switch-off.40 8.2 Electrical isolation.40 9 Wiring systems.41 9.1 General.41 9.2 Aluminium conductors.41 9.3 Cables.41 SIST EN 60079-14:2009

– 4 – 60079-14 © IEC:2007 9.3.1 Cables for fixed wiring.41 9.3.2 Cables supplying transportable and portable equipment.41 9.3.3 Flexible connections for dust.42 9.3.4 Flexible cables.42 9.3.5 Non-sheathed single cores.42 9.3.6 Overhead lines.42 9.3.7 Avoidance of damage.43 9.3.8 Cable surface temperature.43 9.3.9 Flame propagation.43 9.3.10 Connections of cables to equipment.43 9.4 Conduit systems.44 9.5 Cable and conduit systems.45 9.5.1 EPL 'Ga'.45 9.5.2 EPL 'Da'.45 9.5.3 Cable and conduit systems for EPL ‘Gb’, ‘Gc’, ‘Db’ and ‘´Dc’.45 9.6 Installation requirements.45 9.6.1 Circuits traversing a hazardous area.45 9.6.2 Protection of stranded ends.45 9.6.3 Unused cores.45 9.6.4 Unused openings.45 9.6.5 Fortuitous contact.45 9.6.6 Jointing.46 9.6.7 Openings in walls.46 9.6.8 Passage and collection of flammables.46 9.6.9 Static build-up for dust.46 9.6.10 Accumulation of combustible dust.46 10 Additional requirements for type of protection 'd' – Flameproof enclosures.47 10.1 General.47 10.2 Solid obstacles.47 10.3 Protection of flameproof joints.47 10.4 Cable entry systems.48 10.4.1 General.48 10.4.2 Selection of cable glands.48 10.5 Conduit systems.50 10.6 Motors.50 10.6.1 Motors with a converter supply.50 10.6.2 Reduced-voltage starting (soft starting).50 11 Additional requirements for type of protection ‘e’ – Increased safety.51 11.1 Degree of ingress protection of enclosures (IEC 60034-5 and IEC 60529).51 11.2 Wiring systems.51 11.2.1 General.51 11.2.2 Cable glands.51 11.2.3 Conductor terminations.52 11.2.4 Combinations of terminals and conductors for general connection
and junction boxes.52 11.3 Cage induction motors.52 11.3.1 Mains-operated.52 11.3.2 Winding temperature sensors.53 11.3.3 Machines with rated voltage greater than 1 kV.53 SIST EN 60079-14:2009

60079-14 © IEC:2007 – 5 – 11.3.4 Motors with converter supply.54 11.3.5 Reduced-voltage starting (soft starting).54 11.4 Luminaires.54 12 Additional requirements for types of protection 'i' – Intrinsic safety.54 12.1 Introductory remark.54 12.2 Installations to meet the requirements of EPL ‘Gb’ or ‘Gc’.55 12.2.1 Equipment.55 12.2.2 Cables.56 12.2.3 Termination of intrinsically safe circuits.59 12.2.4 Earthing of intrinsically safe circuits.60 12.2.5 Verification of intrinsically safe circuits.61 12.3 Installations to meet the requirements of EPL 'Ga'.63 12.4 Special applications.64 13 Additional requirements for pressurized enclosures.65 13.1 Type of protection 'p'.65 13.1.1 General.65 13.1.2 Ducting.65 13.1.3 Action to be taken on failure of pressurization.66 13.1.4 Multiple pressurized enclosures with a common safety device.68 13.1.5 Purging.68 13.1.6 Protective gas.68 13.1.7 Wiring systems.69 13.2 Motors.69 13.2.1 Motors with a converter supply.69 13.2.2 Reduced-voltage starting (soft starting).69 13.3 Type of protection 'pD'.69 13.3.1 Sources of protective gas.69 13.3.2 Automatic switch-off.70 13.3.3 Alarm.70 13.3.4 Common source of protective gas.70 13.3.5 Switching on electrical supply.70 13.3.6 Motors with a converter supply.71 13.4 Rooms for explosive gas atmosphere.71 13.4.1 Pressurized rooms and analyser houses.71 14 Additional requirements for type of protection 'n'.71 14.1 General.71 14.2 Degree of ingress protection of enclosures (IEC 60034-5 and IEC 60529).72 14.3 Wiring systems.72 14.3.1 General.72 14.3.2 Cable glands.72 14.3.3 Conductor terminations.73 14.4 Motors.73 14.4.1 Machines with rated voltage greater than 1 kV.73 14.4.2 Motors with converter supply.73 14.4.3 Reduced-voltage starting (soft starting).74 14.5 Luminaires.74 15 Additional requirements for type of protection 'o'– Oil immersion.74 16 Additional requirements for type of protection 'q' – Powder filling.74 SIST EN 60079-14:2009

– 6 – 60079-14 © IEC:2007 17 Additional requirements for type of protection 'm' – Encapsulation.74 18 Additional requirements for type of protection 'tD' – Protection by enclosure.74 18.1 Practices A and B.74 18.2 Practice A.74 18.3 Practice B.75 18.4 Motors supplied at varying frequency and voltages.75
Annex A (normative)
Verification of intrinsically safe circuits with more than one associated apparatus
with linear current/voltage characteristics.76 Annex B (informative)
Methods of determining the maximum system voltages and currents in intrinsically safe circuits with more than one associated apparatus with linear current/voltage characteristics (as required by Annex A).77 Annex C (informative)
Determination of cable parameters.80 Annex D (informative)
Safe work procedure guidelines for explosive gas atmospheres.82 Annex E (normative) Potential stator winding discharge risk assessment –
Ignition risk factors.83 Annex F (normative)
Knowledge, skills and competencies of 'Responsible Persons', 'Operatives' and 'Designers'.84 Annex G (informative)
Examples of dust layers of excessive thickness.87 Annex H (normative)
Frictional sparking risks with light metals and their alloys.88 Annex I (informative)
Introduction of an alternative risk assessment method encompassing “equipment protection levels” for Ex equipment.89
Bibliography.94
Figure 1 – Correlation between the maximum permissible surface temperature and depth of dust layers.29 Figure 2 – Selection chart for cable entry devices into flameproof enclosures
for cables complying with item b) of
10.4.2.49 Figure 3 – Earthing of conducting screens.57 Figure B.1 – Series connection – Summation of voltage.78 Figure B.2 – Parallel connection – Summation of currents.78 Figure B.3 – Series and parallel connections – Summations
of voltages and summations of currents.79 Figure G.1a − Excessive layer on top of equipment.87 Figure G.1b − Excessive layer on top of equipment due to low ignition temperature of the dust.87 Figure G.1c − Excessive layer at the sides of equipment.87 Figure G.1d − Completely submerged equipment.87 Figure G.1 – Examples for dust layers of excessive thickness with the requirement of laboratory investigation.87
Table 1 – Equipment protection levels (EPLs) where only zones are assigned.24 Table 2 – Relationship between types of protection and EPLs.25 Table 3 – Relationship between gas/vapour or dust subdivision and equipment group.26 Table 4 – Relationship between gas or vapour ignition temperature and temperature class of equipment.27 SIST EN 60079-14:2009

60079-14 © IEC:2007 – 7 – Table 5 – Limitations of areas.38 Table 6 – Minimum distance of obstruction from the flameproof flange joints
related to the gas group of the hazardous area.47 Table 7 – Assessment for T4 classification according to
component size and ambient temperature.63 Table 8 – Determination of type of protection
(with no flammable release within the enclosure).65 Table 9 – Use of spark and particle barriers.66 Table 10 – Action to be taken when the pressurization with the protective gas fails
for electrical equipment without an internal source of release.67 Table 11 – Summary of protection requirements for enclosures.70 Table 12 – Dust tightness practice A.75 Table 13 – Dust tightness practice B.75 Table I.1 – Traditional relationship of EPLs to zones (no additional risk assessment).91 Table I.2 – Description of risk of ignition protection provided.92
– 8 – 60079-14 © IEC:2007 INTERNATIONAL ELECTROTECHNICAL COMMISSION ____________
EXPLOSIVE ATMOSPHERES –
Part 14: Electrical installations design, selection and erection
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 this end and in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with may participate in this preparatory work. International, governmental and non-governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for Standardization (ISO) in accordance with conditions determined by agreement between the two organizations. 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 interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any misinterpretation by any end user. 4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications transparently to the maximum extent possible in their national and regional publications. Any divergence between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter. 5) IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any equipment declared to be in conformity with an IEC Publication. 6) All users should ensure that they have the latest edition of this publication. 7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and members of its technical committees and IEC National Committees for any personal injury, property damage or other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is indispensable for the correct application of this publication. 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 60079-14 has been prepared by subcommittee 31J: Classification of hazardous areas and installation requirements, of IEC technical committee 31: Equipment for explosive atmospheres. This fourth edition cancels and replaces the third edition published in 2002 and constitutes a technical revision with respect to gases and vapours and incorporates the requirements for dusts from IEC 61241-14 (2004). The incorporation of requirements for dust is without technical change. The significant technical changes with respect to the previous edition are as follows: • Knowledge, skills and competencies of "Responsible Persons”, “Operatives" and "Designers" are explained in Annex F. • Equipment Protection Levels (EPLs) have been introduced and are explained in the new Annex I. • Dust requirements included from IEC 61241-14, Ed. 1.0. SIST EN 60079-14:2009

60079-14 © IEC:2007 – 9 – NOTE Dust requirements are included as an interim presentation for the purpose of this edition and will be refined in a next edition with other require
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