Atex Guide by Tuv

TUV RHEINLAND France 6, rue Halévy 75009 PARIS T +33 (0)1 43 12 31 60 F +33 (0)1 42 66 54 69 www.fr.tuv.com

ATEX GUIDE

TUV RHEINLAND is Notified Body under number 0035

For all the annexes of the 94/9/EC ATEX Directive.

TUV RHEINLAND is Notified Body with European Directives for the following items :

93/42/EEC Medical Devices

98/79/EEC In vitro Diagnostics

94/9/EC ATEX

98/37/EC Machines

97/23/EC Equipment under pressure

Se différencier – Inspirer confiance – Convaincre


CONTEXT

Context The ATEX regulation (concerning EXplosive ATmospheres) is based on two European directives: Directive 1999/92/EC dated December 16th, 1999, « on minimum requirements for improving the

safety and health protection of workers potentially at risk from explosive atmospheres ». Directive 94/9/EC dated March 23rd, 1994, « on the approximation of the laws of the Member States

concerning equipment and protective systems intended for use in potentially explosive atmospheres»,

Date of application Since 1st July 2003, ATEX directives are mandatory and applicable for the whole European Community. All companies which are concerned by the manufacturing, the use or the distribution of equipments intended to be put into service in explosive atmospheres, will have to conform to the essential requirements with regard to safety and health which are envisaged by the ATEX Directives.



What are the obligations of the users ?

Since July 1st, 2003, concerning the prevention of explosions and the protection against them, the user is held:

• to take technical or organizational means adapted with the type of exploitation

• to evaluate the risks of explosion on an overall basis

• to subdivide in zones the sites where explosive atmospheres can arise

• to set up a visible indication of the definite zones.

What are the obligations of the manufacturers ? Since July 1st, 2003, all new equipments for use in explosive atmospheres can only be marketed if they are perfectly in conformity with the requirements of ATEX. Consequently, these equipments will have to carry the ATEX standardized marking on their marking plates.



WHAT IS ATEX ?

What is an explosion ? An explosion is the fast evolution of a system, with release of energy and production of mechanical and possibly thermals effects (serious human and material damage, important formation of gas and heat). The definition, taken from EN 1127-1 standard, can also be quoted: an explosion is a "abrupt reaction of oxidation or decomposition involving a rise in temperature, pressure or both simultaneously".

What is « an explosive atmosphere » ? An "explosive atmosphere" is an atmosphere which could become explosive because of the local and / or operational conditions. It is a mixture of air and flammable substances in the form of gas, vapors, fogs or dust, in which, after ignition, the combustion is propagated to the whole of the mixture which has not been burned yet.

What is an ignition source?

- A sufficiently important source of energy (Mechanical or electrical sparks, electrostatic discharges, naked flames, lightning, etc)

- A sufficiently high temperature (Hot surfaces)



Case of explosion for gas To be explosive, the gas mixture shall be neither too poor, nor too rich in flammable substances:

Case of explosion for vapors The temperature of the flammable liquid shall be sufficiently high to form enough vapors:

* Temperature to which a liquid emits sufficient vapors to form with the air a flammable mixture

Case of explosion for dusts Combustible dust layers or clouds with mix of air and combustible dusts can be explosive:

Surface temperature of process

Self ignition temperature

>

LLE Lower limit of explosiveness

concentration of flammable

substances in air

ULE Upper limit of explosiveness

<

<

Temperature of liquids Flash point *

>



SOME EXAMPLES OF DANGEROUS SUBSTANCES

Gas Vapors Dusts methane butane

propane hydrogen

ethyl carbon carbon bisulphide

acetone oxide of ethylene

aluminium cereals

coal starch

The dangerous substances above defined can be found in several types of industry:

Recycling

Pharmacy

Chemistry

Petrochemistry

Agroalimentary



ATEX CLASSIFICATION

Classification of zones The 94/9/EC Directive defines some zones with risks of explosion, with a distinction between gas atmospheres (G) or dust atmospheres (D).

Presence of explosive atmosphere Zone for Gas (G) Zone for Dust (D)

Permanent presence, under normal operation 0 20

Occasional presence, under normal operation 1 21

Accidental presence, in case of dysfunction 2 22

Categories of apparatuses To recognize the zones where the apparatuses can be installed, they are split into 2 majors fields (mines and surface) and classified with the following categories:

Category of apparatus

Surface Mines Suitable zones

1 M1 Zone 0 or zone 20 2 M2 Zone 1 or zone 21

3 - Zone 2 or zone 22



Gas groups 4 groups of gas are defined, based on characteristics of 5 representative gases (the ones used for the type tests)

Apparatus group Gas group Gas Minimal source of ignition (µJ)

Group I (Mines) I Methane 300

IIA Propane 240 IIB Ethylene 70

Acetylene 17 Group II (Surfaces) IIC Hydrogen 17

Temperature classes The temperature class defines the maximal surface temperature of an apparatus, based on a defined maximal operating ambient temperature:

Temperature Classes Corresponding surface temperature (°C)

T1 450 T2 300 T3 200 T4 135 T5 100 T6 85



EXAMPLES OF CLASSIFICATION OF GAS AND DUSTS

Gas

Gas Corresponding Gas Group

Corresponding Temperature class

Acetone IIA T1 Acetylene IIC T2 Ammonia IIA T1

Butane IIA T2 Cyclohexane IIA T3

Ethanol IIA T2 Ethylene IIB T2 Hydrogen IIC T1 Kerosene IIA T3 Methane IIA T1 Methanol IIA T2

Methyl Ethyl Ketone IIB T2 Propane IIA T1

Propan 1 ol IIA T2 Propan 2 ol IIA T2

Tetrahydrofuran IIB T3 Toluene IIA T1 Xylene IIA T1

Dusts

Typical ignition temperature (°C) Dust Cloud Layer

Aluminium 590 > 450 Coal dust 380 225

Flour 490 340 Grain dust 510 300

Methyl cellulose 420 320 Phenolic resin 530 > 450

Polythene 420 Melts PVC 700 > 450 Soot 810 570

Starch 460 435 Sugar 490 460



EQUIVALENCES BETWEEN

CSA / US MARKINGS AND

CENELEC / CEI MARKINGS

Gas groups

Apparatus group

Gas group CENELEC

CEI Groups / Class / Zones

CSA US Representative

gas

Group I (Mines) I Mines Methane IIA D Class I Div 1/2 IIA Class I Zone 0/1/2 Propane IIB C Class I Div 1/2 IIB Class I Zone 0/1/2 Ethylene

IIB + H2 B Class I Div 1/2 Hydrogen Group II

(Surfaces) IIC A Class I Div 1/2 IIC Class I Zone 0/1/2 Acetylene

Classification of zones

Presence of explosive

atmosphere Permanent presence, under

normal operation Occasional presence,

under normal operation Accidental presence, in

case of dysfunction

CENELEC / CEI

Zone 0 (Gas) Zone 20 (Dust)

Zone 1(Gas) Zone 21 (Dust)

Zone 2 (Gas) Zone 22 (Dust)

CSA US Class I Div 1 / Class I Zone 0 (Gas)

Class II Div 1 (Dust) Class III Div 1 (Fibers)

Class I Div 1 / Class I Zone 1 (Gas) Class II Div 1 (Dust)

Class III Div 1 (Fibers)

Class I Div 2 / Class I Zone 2 (Gas) Class II Div 2 (Dust)

Class III Div 2 (Fibers)

References CEC : Canadian Electrical Code NEC : National Electrical Code



` Temperature classification

Maximum surface temperature °C

T° class US (NEC 505) IEC CENELEC

T° class US (NEC 500)

450 T1 T1 300 T2 T2 280 - T2A 260 - T2B 230 - T2C 215 - T2D 200 T3 T3 180 - T3A 165 - T3B 160 - T3C 135 T4 T4 120 - T4A 100 T5 T5 85 T6 T6



HOW TO PREVENT AN EXPLOSION ?

Compliance of apparatuses: Only the equipments which are approved for ATEX can be used in explosive atmospheres areas. The compliance with ATEX can be evaluated by an ATEX notified body, or can be self evaluated by the manufacturer, depending on the belonging category of apparatus:

Equipments Category Conformity assessment Involved annexes of directive 94/9/EC

1 or M1 Certification by Notified body required III and IV or V IX

2 or M2 Certification by Notified body required III and IV or VI or VII IX Electrical

equipments

3 Self certification or Voluntary certification by a Notified body

Self certification III IX

1 or M1 Certification by Notified body required III and IV or V IX

2 or M2 Archiving file at Notified body or Voluntary certification by a Notified body

VIII III IX

Mechanical equipments

3 Self certification or Voluntary certification by a Notified body

Self certification III IX

By acting on one of the following criteria: • Preventing the formation of an explosive atmosphere

• Preventing the effectiveness of ignition sources

• Preventing the propagation of ignition



Types of protection:

Electrical apparatuses for GAS

Type of protection Concept

ia : intrinsic safety No spark or no thermal effect due to the choice of

components and the limitation of energy, taking into account 2 faults

ma : encapsulation All components encapsulated in resin

possible combinations between 2 independent

types of protection of CAT 2

Refer to EN 60079-26 standard

d : flameproof enclosure Enclosure which can withstand an explosion and prevent its propagation

e : increased safety Enclosure in which there is no spark or no hot surface in normal operation

mb : encapsulation All components encapsulated in resin

o : oil immersion Components protected by an enclosure full of oil

p : pressurization Components protected by an enclosure which is

pressurized with a protective gas at a higher pressure than the atmosphere

q : powder filling All components protected by an enclosure full of filling material

ib : intrinsic safety No spark or no thermal effect due to the choice of

components and the limitation of energy, taking into account 1 fault

n type of protection Only used for equipments installed in places where

no explosive atmosphere is present, or is present for short time



Electrical apparatuses for DUST


tD : protection by enclosures

All components are protected against ingress of dust by an enclosure

pD type of protection Components protected by an enclosure which is


iD : intrinsic safety No spark or no thermal effect due to the choice of components and the limitation of energy

mD : encapsulation All components encapsulated in resin

Mechanical apparatuses GAS and DUST


fr : flow restricting enclosure Restriction of flow inside the enclosure

d : flameproof enclosure Enclosure which can withstand an explosion and prevent its propagation

g : Inherent safety Define the maximal criteria (speed, nature of

materials, potential energies) so as there is no effective ignition source

c : constructional safety Selection of components with no ignition source

b : control of ignition source

Choose of control and monitoring devices which allow the de-energizing of equipment in case of

failure

p : pressurization Components protected by an enclosure which is


k : liquid immersion Components protected by an enclosure full of liquid



Ingress protection code

First figure : protection against

solid foreign objects Index Index

Second figure : Protection against water penetration

Non protected 0 0 Non protected Back of a hand Solid objects Ø 50 mm or more

1 1 Vertically falling water drops

Finger Solid objects Ø 12,5 mm or more

2 2 Vertically falling water drops when enclosure is tilted up to 15°

Tool Solid objects Ø 2,5 mm or more

3 3 Spraying water up to 60° from vertical

Wire Solid objects Ø 1 mm or more

4 4 Splashing water from any direction

Wire 1mm Dust protected 5 5 Jets of water from any

direction

6 Powerful jets of water from any direction

7 Immersion Wire 1mm Dust tight 6

8 Continuous immersion



MARKING

Example of marking of equipments and significance

CE 035 II 2 G or D EEx d IIC T6

IP 66 T80°C

Dust Gas Category of apparatus Group of apparatus for surface Logo for explosive atmosphere Number of the notified body which has checked the production quality insurance CE Marking Temperature class Gas group Type of protection Answer to European CENELEC standards Maximal surface temperature for Dust Ingress protection against solids and liquids



APPLICABLE STANDARDS

The current standards used for the passage to the new Directive 94/9/EC in July 2003, are the series 5 standards (EN 50014, EN 50018, EN 50019, etc.). To achieve to the harmonization of the reference frames, gradually, from July 2006, the series 5 standards are destined to be replaced by series 6 standards (EN 60079-0, EN 60079-1, etc.), which are in fact based on the international IEC standards. The main change is the clear separation between the standards for the use in gas atmospheres (EN 60079 standards) and the standards for the use in presence of combustible dusts (EN 61241 standards). And as a consequence, new types of protection (shown above) have appeared for dusts. The series 6 standards bring in addition more severe requirements and additional tests, for which any manufacturer will have to comply if they want to respect the essential requirements for health and safety of the directive 94/9/EC. An other new is also the coming out of the mechanical standards. They provide a methodology, by the realization of a risk analysis, to define what are the potential sources of ignition due to the mechanical construction and/or operating of the equipment. The tables shown below try to give, when the information is available, when will the current series 5 standards be replaced by the new series 6. To see all the specific standards related to directive 94/9/EC (Electrostatic painting, Internal combustion engines, Packaging machines, Pumps, Refrigerating systems, etc), you can have a look to the following internet links : http://www.newapproach.org/Directives/ProductFamilies.asp?94/9/EC http://europa.eu.int/comm/enterprise/newapproach/standardization/harmstds/reflist/atex.html



ELECTRICAL APPARATUS FOR EXPLOSIVE GAS ATMOSPHERES

Previous standard

New Standard Title

Date of cancellation of

the series 5 standards

EN 50014 (1997) + A1 and A2 EN 60079-0 (2004) General requirements 01-03-2007

EN 50018 (2000) + A1 EN 60079-1 (2004) Flameproof enclosures ‘d’ 01-03-2007

EN 50016 (2002) EN 60079-2 (2004) Pressurized enclosures ‘p’ 01-06-2007

EN 50017 (1998) prEN 60079-5 (2006) Requirements for Powder filling ‘q Not yet defined

EN 50015 (1998) prEN 60079-6 (2006) Requirements for Oil immersion ‘o’ Not yet defined

EN 50019 (2000) EN 60079-7 (2003) Increased safety ‘e’ 01-07-2006

None EN 60079-10 (2003) Classification of hazardous areas -

EN 50020 (2002) prEN 60079-11 (200X) Intrinsic safety ‘i’ Not yet defined

None EN 60079-14 (2003) Electrical installations in hazardous areas (other than mines) -

EN 50021 (1999) EN 60079-15 (2005) Type of protection ‘n’ 01-07-2006

None EN 60079-17 (2003) Inspection and maintenance of electrical installations in hazardous areas (other than mines)

-

EN 50028 (1987) EN 60079-18 (2004) Encapsulation ‘m’ 01-04-2007

None prEN 60079-19 (2005)

Repair and overhaul for apparatus used in explosive atmospheres (other than explosives)

-

EN 50039 (1980) EN 60079-25 (2004) Intrinsically safe systems 01-12-2006

EN 50284 (1999) EN 60079-26 (2004) Construction, test and marking of Group II category 1G electrical apparatus

01-04-2007

None EN 60079-27 (200X) Fieldbus intrinsically safe concept (FISCO) and fieldbus non-incendive concept (FNICO)

-

None prEN 60079-28 (200X)

Protection of equipments and transmission systems using optical radiation

-



ELECTRICAL APPARATUS FOR EXPLOSIVE GAS ATMOSPHERES

(CONTINUED)

Previous standard

New Standard Title



EN 62086-1 (2005) None Electrical resistance trace heating –

General and testing requirements -

EN 62086-2 (2005) None

Electrical resistance trace heating – Application guide for design, installation and maintenance

-

prEN 14986 (2004) None Design of fans working in potentially

explosive atmospheres -

EN 12874 (2001) None Flame arresters – Performance requirements, test methods and limits for use

-

EQUIPMENTS FOR MINES

Previous standard

New Standard Title



EN 62013-1 (2002) None

Caplights for use in mines susceptible to firedamp - Part 1 : General requirements - Construction and testing in relation to the risk of explosion

-

EN 62013-2 (2000) None

Caplights for use in mines susceptible to firedamp - Part 2 : Performance and other safety-related matters

-

EN 50033 (1991) None Caplights for mines susceptible to firedamp -

EN 50303 (2000) None

Group I, Category M1 equipment intended to remain functional in atmospheres endangered by firedamp and/or coal dust

-

EN 50394-1 (2004) None Group I – Intrinsically safe systems –

Part 1 : Construction and testing -



ELECTRICAL APPARATUS FOR USE IN THE PRESENCE OF COMBUSTIBLE DUST

Previous standard

New Standard Title



EN 50281-1-1 (1998) + A1

EN 61241-0 (200X) : General requirements

Electrical apparatus protected by enclosures – Construction and testing

Not yet defined

None EN 61241-1 (2004) Protection by enclosures ’tD’ -

None prEN 61241-4 (2004) Protection by pressurization ‘pD’ -

None EN 61241-11 (200X) Protection by intrinsic safety "iD" -

None EN 61241-18 (2004) Protection by encapsulation ‘mD’ -

EN 61241-14 (2004) : Selection and installation EN 50281-1-2

(1998) + A1 EN 61241-17 (2005) : Inspection and maintenance

Electrical apparatus protected by enclosures – Selection, installation and maintenance

01-09-2007

EN 50281-2-1 (1998) None

Test methods – Methods for determining the minimum ignition temperatures of dust

-

EN 50281-3 (2002) EN 61241-10 (2004)

Classification of areas where combustible dusts are or may be present

01-07-2007

NON ELECTRICAL EQUIPMENT FOR POTENTIALLY EXPLOSIVE ATMOSPHERES

Standard Title

EN 13463-1 (2001) General requirements

EN 13463-2 (2004) Protection by flow restricting enclosure ‘fr’

EN 13463-3 (2005) Protection by flameproof enclosure ‘d’

EN 13463-5 (2003) Protection by constructional safety ‘c’

EN 13463-6 (2005) Protection by control of ignition sources ‘b‘

prEN 13463-7 (2005) Protection by pressurization ‘p’

EN 13463-8 (2003) Protection by liquid immersion ‘k’



IEC STANDARDS

Standard Title

IEC 60079-0 (2004) Electrical apparatus for explosive gas atmospheres - General requirements

IEC 60079-1 (2003) Electrical apparatus for explosive gas atmospheres - Flameproof enclosures ‘d’

IEC 60079-1-1 (2002) Electrical apparatus for explosive gas atmospheres - Part 1-1: Flameproof enclosures 'd' - Method of test for ascertainment of maximum experimental safe gap

IEC 60079-2 (2001) Electrical apparatus for explosive gas atmospheres - Pressurized enclosures ‘p’

IEC 60079-4 (1975) + A1

Electrical apparatus for explosive gas atmospheres. Part 4: Method of test for ignition temperature

IEC 60079-5 (1997) + A1

Electrical apparatus for explosive gas atmospheres - Requirements for Powder filling ‘q

IEC 60079-6 (1995) Electrical apparatus for explosive gas atmospheres - Requirements for Oil immersion ‘o’

IEC 60079-7 (2001) Electrical apparatus for explosive gas atmospheres - Increased safety ‘e’

IEC 60079-10 (2002) Electrical apparatus for explosive gas atmospheres - Classification of hazardous areas

IEC 60079-11 (1999) Electrical apparatus for explosive gas atmospheres - Intrinsic safety ‘i’

IEC/TR 60079-12 (1978) Electrical apparatus for explosive gas atmospheres - Part 12: Classification of mixtures of gases of vapours with air according to their maximum experimental safe gaps and minimum igniting currents

IEC/TR 60079-13 (1982) Electrical apparatus for explosive gas atmosphere - Part 13: Construction and use of rooms or buildings protected by pressurization

IEC 60079-14 (2002) Electrical apparatus for explosive gas atmospheres - Electrical installations in hazardous areas (other than mines)

IEC 60079-15 (2005) Electrical apparatus for explosive gas atmospheres - Type of protection ‘n’

IEC/TR 60079-16 (1990) Electrical apparatus for explosive gas atmospheres. Part 16: Artificial ventilation for the protection of analyser(s) houses

IEC 60079-17 (2002) Electrical apparatus for explosive gas atmospheres - Inspection and maintenance of electrical installations in hazardous areas (other than mines)

IEC 60079-18 (2004) Electrical apparatus for explosive gas atmospheres - Encapsulation ‘m’

IEC 60079-19 (1993) Repair and overhaul for apparatus used in explosive atmospheres (other than explosives)

IEC/TR 60079-20 (1996) Electrical apparatus for explosive gas atmospheres - Part 20: Data for flammable gases and vapours, relating to the use of electrical apparatus



IEC STANDARDS (CONTINUED)

Standard Title

IEC 60079-25 (2003) Electrical apparatus for explosive gas atmospheres - Intrinsically safe systems

IEC 60079-26 (2004) Electrical apparatus for explosive gas atmospheres - Construction, test and marking of Group II category 1G electrical apparatus

IEC 60079-27 (2005) Electrical apparatus for explosive gas atmospheres - Fieldbus intrinsically safe concept (FISCO) and fieldbus non-incendive concept (FNICO)

IEC 60079-28 (200X) Electrical apparatus for explosive gas atmospheres - Protection of equipments and transmission systems using optical radiation

IEC 61241-0 (2004) Electrical apparatus for use in the presence of combustible dust - General requirements

IEC 61241-1 (2004) Electrical apparatus for use in the presence of combustible dust - Protection by enclosures ’tD’

IEC 61241-2-1 (1994) 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 61241-2-2 (1993) Electrical apparatus for use in the presence of combustible dust - Part 2: Test methods - Section 2: Method for determining the electrical resistivity of dust in layers

IEC 61241-2-3 (1994) Electrical apparatus for use in the presence of combustible dust - Part 2: Test methods - Section 3: Method for determining minimum ignition energy of dust/air mixtures

IEC 61241-4 (2001) Electrical apparatus for use in the presence of combustible dust - Type of protection 'pD'

IEC 61241-10 (2004) Electrical apparatus for use in the presence of combustible dust - Classification of areas where combustible dusts are or may be present

IEC 61241-11 (2005) Electrical apparatus for use in the presence of combustible dust - Protection by intrinsic safety "iD"

IEC 61241-14 (2004) Electrical apparatus for use in the presence of combustible dust - Selection and installation

IEC 61241-17 (2005) Electrical apparatus for use in the presence of combustible dust - Inspection and maintenance

IEC 61241-18 (2004) Electrical apparatus for use in the presence of combustible dust - Protection by encapsulation ‘mD’



USEFUL LINKS TUV Rheinland France http//www.fr.tuv.com TUV Rheinland http//www.tuv.com IECEx (International Electrotechnical Commission Scheme for certification to standards relating to equipments for use in Explosive Atmospheres) http://www.iecex.com/

EUROPEAN COMMISSION (Equipment intended for use in Potentially Explosive Atmospheres (ATEX)) http://europa.eu.int/comm/enterprise/atex/index_en.htm

New Approach Standardization in the Internal Market http://www.newapproach.org/

CENELEC (European Committee for Electrotechnical Standardization) http://www.cenelec.org/Cenelec/Homepage.htm

IEC (International Electrotechnical Commission) http://www.iec.ch/

UTE (French body of Electrotechnical standardization) http://www.ute-fr.com/FR/

AFNOR (French association of standardization) http://www.afnor.fr/portail.asp

CLATEX (French ATEX Committee) http://www.industrie.gouv.fr/sdsi/daec/clatex/clatex.html



CONTACTS Kathy MILLET Fabienne BAUDOIN Ingénieur de Certification ATEX Assistante Certification ATEX Agence de Paris Agence de Paris Tel : + 33 (0)1 43 12 34 08 Tel : + 33 (0)1 43 12 31 73 Fax : +33 (0)1 42 66 54 69 Fax : +33 (0)1 42 66 54 69 mobile : +33 (0)6 88 24 80 46 Jean-Philippe BUI Bernard WALKER Certification Manager Service Inspection Agence de Lyon Agence de Paris Tel : + 33 (0)4 78 47 74 96 Tel : + 33 (0)1 43 12 31 74 mobile : +33 (0)6 88 24 80 40 Fax : +33 (0)1 42 66 54 69

TUV RHEINLAND France 6, rue Halévy 75009 PARIS FRANCE [email protected]

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