Hazardous Areas,

Explosive Atmospheres
and Equipment Group
North America

Atex & IECEx

Protection Concepts [NEC & CEC]

Type of
Protection

Code
(EPL)

Country

Class

Division /
Zone

Standard

--

US

General
AEx
Requirements

Ex
AEx e (Gb)
Increased Safety
Ex e (Gb)
Non-Incendive

NI

Non-Sparking

AEx nA (Gc)
Ex nA (Gc)

Explosion-proof
Flame-proof
Powder Filled
Enclosed Break

XP
AEx d (Gb)
Ex d (Gb)
AEx q (Gb)
Ex q (Gb)
AEx nC (Gc)
Ex nC (Gc)
IS

Intrinsic

Safety1

Limited Energy

AEx ia (Ga)
AEx ib (Gb)
AEx ic (Gc)
Ex ia (Ga)
Ex ib (Gb)
Ex nL (Gc)
Type X
Type Y
Type Z

Pressurized

Restricted
Breathing

Encapsulation

Oil Immersion

AEx px (Gb)
Ex px (Gb)
AEx py (Gb)
Ex py (Gb)
AEx pz (Gc)
Ex pz (Gc)
AEx nR (Gc)
Ex nR (Gc)
AEx ma (Ga)
AEx mb (Gb)
AEx mc (Gc)
Ex m
AEx o (Gb)
Ex o (Gb)

CA
US
CA
US
CA
US
CA
US
CA
US
CA
US
CA
US
CA
US
CA
US

Class I
Class I
Class I
Class I

US
CA
US
CA
US
CA
US
CA
US
CA
US
CA
US
CA
US
CA
US
CA

Zone 1
Division 2
Zone 2

Class I

Division 1

Class I

Zone 1

Class I

Zone 1

Class I

Zone 2
Division 1

Class I

CA
CA

Division 1, 2

Class I

Zone 0
Zone 1
Zone 2
Zone 0
Zone 1
Zone 2

Division 1

Division 2
Class I
Zone 1

Zone 2
Class I

Zone 2

Class I

Zone 0
Zone 1
Zone 2
Zone 1

Class I

Zone 1

FM 3600
ISA 60079-0
CSA C22.2 No. 60079-0
ISA 60079-7
CSA C22.2 No. 60079-7
ISA 12.12.01/FM 3611
CSA C22.2 No. 213
ISA 60079-15CSA
C22.2 No. 60079-15
UL 1203
CSA C22.2 No. 30
ISA 60079-1
CSA C22.2 No. 60079-1
ISA 60079-5
CSA C22.2 No. 60079-5
ISA 60079-15
CSA C22.2 No. 60079-15
UL 913 / FM 3610
CSA C22.2 No. 157
ISA 60079-11

General
Requirements

-Ex

Dust-Ignition
proof

DIP

Dust Protected

NI

Class II

US

Class III
--

US
CA
US
CA

AEx ta (Da)
AEx tb (Db)
AEx tc (Dc)

US

Ex ta

Enclosure

CA

Ex tb
Ex tc
Fiber & Flying
Protection

US
CA

-AEx maD
AEx mbD

US

Ex ma
Encapsulation
Ex mb

CA

Ex mc
Type X
Pressurization

Type Y
Type Z

Intrinsic Safety

Note 1:

Note 2:

AEx pD
IS
AEx iaD
AEx ibD
IS

US
CA
US
CA
US
CA
US
US

Class II
Class II

Class II
Class III
Class II
Class III
Class II
Class III
Class III
Class II
Class III
Class II
Class III
Class II
Class III

No arcs, sparks
or hot surfaces

1
2
3, 3R, 3S
4, 4X
5
6
6P
12, 12K
13

Motors and Generators

(Explosion-proof &
Dust-ignition proof)

CSA C22.2 No. 145 Electric motors and

generators for use in hazardous (classified)
locations 3

UL 783 Electric flashlights and lanterns for

use in hazardous (classified) locations

Flashlights

Fuel Dispensing
Equipment
Limit energy of sparks
and surface
temperature

CSA C22.2 No. 60079-11

NFPA 496 (FM 3620)

NFPA 496
NFPA 496 (FM 3620)
NFPA 496
NFPA 496 (FM 3620)
NFPA 496
ISA 60079-2
CSA C22.2 No. 60079-2
ISA 60079-2
CSA C22.2 No. 60079-2 Keep flammable gas
out
ISA 60079-2
CSA C22.2 No. 60079-2
ISA 60079-15
CSA C22.2 No. 60079-15

Note 3:

UL 87 Power-operated dispensing devices

for petroleum products
UL 87A Dispensers for gasoline and ethonol
blends, E0 to E85
UL 87B Dispensers for diesel fuel, bio diesel
blends to B20, kerosene and fuel oil
UL 87C Dispensers for diesel exhaust fluids

Hydrogen

Group B
Class I
Flammable Gases

Ethylene

Group C

Continuous Hazard
Intermittent Hazard

IIIB 6

IIIA 6

Not Applicable

Zone Scheme

Definitions

Zone 0 / Zone 20

A place in which an explosive atmosphere is continually present

Hazard Under Abnormal

Conditions

Division 2

Zone 2 / Zone 22

A place in which an explosive

atmosphere is likely to occur in
normal operation
A place in which an explosive atmosphere is not likely to occur in
normal operation, but may occur
for short periods

Atmosphere Groups

Division 2

UL 913 / FM 3610

IIIC 6

Group F

Zone 1 / Zone 21

Limit energy of
sparks and
surface
temperature

For associated intrinsically safe apparatus suitable for installation in a hazardous location, the symbol for the type of protection ia
or ib are enclosed within square brackets on the marking, e.g. AEx d [ia] IIC T4.
For intrinsically safe apparatus not suitable for installation in a hazardous location, both the symbol Ex or AEx and the symbol for
the type of protection ia or ib are enclosed within the same square brackets on the marking, e.g. [AEx ia] IIC;
in this case, a temperature class is not included.
Zones 20-22 are not currently classifed in the Canadian Electric Code (CEC).

NEC 500 CEC

Equipment
Protection
Level (EPL)

Temperature
Class (T1 - T6)

Gas Group

Type of
Protection

Explosion
Protection

Environment*

Equipment
Category*

1, 2
IEC 60079-28

Inherently safe
protected by shutdown
No arcs, sparks or hot
surfaces
Enclosure IP54 or better

Gb

1, 2

IEC 60079-7

nA

Gc

IEC 60079-15

Flame-proof

Gb

1, 2

IEC 60079-1

Type n (Enclosed Break)

nC

Gc

IEC 60079-15

Quartz / Sand Filled

Gb

1, 2

IEC 60079-5

Quench the flame

ia
ib
ic
px
py
pz
nC
nR
ma
mb
mc

Ga
Gb
Gc

0, 1, 2
1, 2
2

IEC 60079-11

Limit the energy of sparks

and surface temperatures

Gb

1, 2

Gc

Gc

IEC 60079-15

Ga
Gb
Gc

0, 1, 2
1, 2
2

IEC 60079-18

Gb

1, 2

IEC 60079-6

--

--

20, 21, 22

IEC 60079-0

ta
tb
tc
ia
ib
ic
ma
mb
mc

Da
Db
Dc
Da
Db
Dc
Da
Db
Dc
Db
Dc

20
21
22
20
21
22
20
21
22
21, 22
22

Increased Safety
Type n (Non-Sparking)

Intrinsic Safety

Type n (Sealing & Hermetically Sealed)

Type n (Restricted Breathing)

Enclosure

Intrinsic Safety

Encapsulation

pD

Contain the explosion,

quench the flame

IEC 60079-2

Keep the flammable

gas out

IEC 60079-31

Standard protection
for dusts, rugged tight
enclosure

IEC 60079-11

Similar to enclosure, but

with some relaxations if
circuit inside is intrinsically
safe

IEC 60079-18

Protection by
encapsulation of incendive
parts

IEC 61241-4

Protection by
pressurization of enclosure

General Requirements

--

--

0, 1, 2
20, 21, 22

EN 13463-1

Low potential energy

Flow Restricted Enclosure

fr

--

2, 22

EN 13463-2

Flame-proof Enclosure

--

1, 2, 21, 22 EN 13463-3

Relies on tight seals, closely

matched joints and tough
enclosures to restrict the
breathing of the enclosure

Constructional Safety

--

0, 1, 2
20, 21, 22

EN 13463-5

Ignition hazards eliminated

by good engineering methods

Control of Ignition Sources

--

0, 1, 2
20, 21, 22

EN 13463-6

Control equipment fitted to

detect malfunctions

Purged / Pressurized

--

1, 2
21, 22

EN 60079-2
EN 61241-4

Liquid Immersion

--

0, 1, 2
20, 21, 22

EN 13463-8

Ingress Protection
Codes [IEC 60529]
First Number (protect Second Number
from solid bodies)
(protect from water)
0
1
2
3
4
5
6

No Protection
Objects > 50 mm
Objects > 12.5 mm
Objects > 2.5 mm
Objects > 1.0 mm
Dust-Protected
Dust-Tight

0
1
2
3
4
5
6
7
8

NEC 505 / IEC - Group II

450 C (842F)

T1

300 C (572F)

T2

280 C (536F)

T2A

260 C (500F)

T2B

230 C (446F)

T2C

215 C (419F)

T2D

200 C (392F)

T3

180 C (356F)

T3A

165 C (329F)

T3B

160 C (320F)

T3C

135 C (275F)

T4

120 C (248F)

T4A

100 C (212F)

T5

T5

85 C (185F)

T6

T6

Note 7:

Gb

IIA 5

Group G

Division Scheme

Max. Surface Temperature

ISA 61241-11

IIA

Classication of Divisions and Zones

Hazard Level

Op pr
Op sh
Op is
e

IEC 60079-0

Non-Electrical Equipment

IIB

Group E 4

Class III
Fibers and Flyings

0, 1, 2

0, 1, 2

Pressurized

IIC

Note 4: Group E is applicable to Class II, Division 1 only.

Note 5: Metane is a Group IIA Gas for non-mining applications.
Note 6: Groups IIIA, IIIB and IIIC have not been adopted by the Canadian Electrical Code.

CSA C22.2 No. 60079-18

Zone 21
Division 1
Zone 20
Zone 21
Division 1

Zone Groups

Group D

Class II
Combustible Dusts

--

Electrical Equipment for Combustible Dusts (D)

Division Groups
Group A

--

Ga

General Requirements

Hazard Class

Combustible Fibers and Flyings

ISA 61241-18

Optical Radiation

Oil Immersion

Combustible Dusts not in Group E or F

(Flour, Grain, Wood, Plastics, Chemicals)

UL 1203 / ISA 12.12.01

CSA C22.2 No. 25

General Requirements

CSA C22.2 No. 22 Electrical equipment for

flammable and combustible fuel dispensers

Combustible Carbonaceous Dusts

Division 1

Division 2

Areas classified for fuel dispensing equipment per national and local codes

Basic Concept
of Protection

Electrical Equipment for Gases, Vapors and Mists (G)

Purged / Pressurized

Acetylene

Combustible Metal Dusts

Keep combustible
dust out

Typical IEC
Symbol Typical
IEC EPL Zone(s) Standard

Type of Protection

Encapsulation

Substance

G Ex d IIC T4 Gb

Protection Concepts [NEC & CEC]

Atmosphere Groups

CSA C22.2 No. 60079-18

ISA 60079-6
CSA C22.2 No. 60079-6

NFPA 496 (FM 3620)

NFPA 496
NFPA 496 (FM 3620)
NFPA 496
NFPA 496 (FM 3620)
NFPA 496
ISA 61241-2
UL 913 / FM 3610

Class I, Divisions 1, 2
Class II, Divisions 1, 2
Class I, Zones 1, 2

North America, Atex & IECEx

Methane

CSA C22.2 No. 60079-31

Zone 20
Zone 21

Control panels located in ordinary locations

with intrinsically safe barriers:
Class I, Division 1
Class I, Zone 0, 1
Class II, Division 1

UL 674 and CSA 145 are harmonized standards.

ISA 60079-18

Division 1

Division 1, 2

Associated apparatus for the following

hazardous (classified) locations:
Class I, Division 1
Class I, Zone 0, 1
Class II, Division 1
Class III, Division 1
Class II, Zone 20, 21

II 2

* Atex only

UL 1238 Control equipment for use with

flammable liquid dispensing devices

Propane

Division 2

Class I, Division 1, Groups B,C,D

Class I, Zone 1, Groups IIA, IIB, IIB + H2
Class II, Division 1, Groups E, F, G
Class II, Zones 20, 21

Class I, Divisions 1, 2
II, Divisions 1, 2
UL 823 Electric heaters for use in hazardous Class
Class
III, Divisions 1, 2
(classified) locations
Class I, Zone 1
Class II, Zones 20, 21, 22

Contain the explosion

and extinguish the
flame

CSA C22.2 No. 60079-15

0167

Equipment Group*

UL 674 Electric motors and generators

for use in hazardous (classified) locations3

UL 698A Industrial control panels relating

to hazardous (classified) locations

Heaters

T1

T2

No protection
Vertical drip
Angled drip
Spraying
Splashing
Jetting
Powerful jetting
Temporary immersion
Continuous immersion

pressure and
9 High
temperature water jet

ATEX Equipment Atmosphere

Category

For Group I applications (ATEX and IECEx only), electrical apparatus has fixed temperature limits of 150C (where layers of coal dust
can form) and 450C (where coal dust is not expected to form a layer).

Group Environment

Coal Mining

I
IIA

Gases, Vapors
and Mists

IIB

Typical
Substance

Location

Surface and
Other
Locations

Methane
(Fire damp)
Methane,
Propane, etc.
Ethylene

IIC

Hydrogen,
Acetylene, etc.

IIIA

Combustible flyings
Combustible
Dusts

IIIB

Surface and
Other
Locations

Non-conductive
Conductive

IIIC

Two faults, Remain energized

and functioning

M2

High Mb

Severe normal operation, Deenergize in exp. atmosphere

1G, 1D

Very High

Two faults

I (Mines with Firedamp)

II (All Other Areas)

[EPL] Equipment Required Protection

Protection Level Performance & Operation
Very High Ma

M1

T4

Atmosphere Groups
[ATEX & IECEx]

Equipment Groups [ATEX]

Equipment Group

T3

Enclosure is purged and pressurized to prevent ignition

sources from arising
Enclosure uses liquid to
prevent contact with
explosive atmosphere

Methane & Dust

2G, 2D

Gas, Vapor, Mist, Dust High

3G, 3D

E q u i p m e n t Ca te g o ri e s
& P ro te c ti o n L e v e l s 8

One fault

Low

Normal operation

AT E X Ca te g o ri e s v s .
Zones of Use8
Zone of Use

Other CE Directives That May Be Applicable

Equipment Typical Equipment

ATEX
Category Protection
Zone Suitability
Levels

Equipment
Category ATEX

Gas,Vapors & Mist

Electromagnetic Compatibility (EMC)

Directive 2004/108/EC

1G

Ga

Suitable for Zones 0, 1, 2

Category 1

Zone 0, 1, 2

Zone 20, 21, 22

Machinery

Directive 2006/42/EC

1D

Da

Suitable for Zones 20, 21, 22

Category 2

Zone 1, 2

Zone 21, 22

Directive 97/23/EC

2G

Gb

Suitable for Zones 1, 2

Protection against rain, snow

Pressure Equipment

Category 3

Zone 2

Zone 22

2D

Db

Suitable for Zones 21, 22

Protection against rain, snow, hose directed water and corrosion (X only)

Low Voltage (excludes equipment for use in explosive atmospheres - see ATEX Annex II 1.2.7)

Directive 2006/95/EC

3G

Gc

Suitable for Zone 2

Indoor

Protection against angled dripping water, dust, fibers, flyings

Radio Equipment and Telecommunications Terminal Equipment (R&TTE)

Directive 1999/5/EC

3D

Dc

Suitable for Zone 22

Indoor / Outdoor

Protection against temporary submersion

Enclosure Type Ratings [NEC & CEC]

Type

Class I, Divisions 1, 2
Class II, Divisions 1, 2

Division 1

Class II

Class III

CSA C22.2 No. 137 Electric luminaires

for use in hazardous locations

CSA C22.2 No. 14 Industrial control equipment Section 4.18

FM 3600
Division 1, 2
CSA C22.2 No. 25
FM 3600
Zone 20, 21, 22 ISA 60079-0
UL 1203
Division 1
CSA C22.2 No. 25
ISA 12.12.01 / FM 3611
Division 2
CSA C22.2 No. 25
2
Zone 20
Zone 212
ISA 60079-31
2
Zone 22

Division 1

Class II

UL 844 Luminaires for use in

Hazardous (Classified) Locations

Class I, Divisions 1, 2
Class II, Divisions 1, 2
Class I, Zones 1, 2
Class II, Zones 20, 21, 22
Class III

Industrial
Control Panels

Electrical Equipment for Combustible Dust - Class II & Class III

US
CA

Class & Division

Luminaires

Basic Concept
of Protection

Electrical Equipment for Flammable Gas, Vapors and Mist - Class I

Standard(s)

Specific Marking
for Explosion
Protection*

Ga
Equipment
ProtectionLevel

IIC

Typical ATEX and IECEx Marking

Notified Body
Number*

T4
Temperature
Class

ia

Product Category

Gas Group

Approved to
US Standards

Area
Classification

Hazard Class

Class Zone AEx

I
0

T4
Temperature
Class

Gas Group

Hazard Class

Area
Classification

Class Divi- Groups

I
sion 1 A&B

Zone Scheme

Protection
Concept Code

Division Scheme

Standards by Product Types

Complies with
European Directive*

Typical North American Marking

Area
Indoor
Indoor / Outdoor

Indoor

Brief Definition
General Purpose
Protection against angled dripping water

Protection against circulating dust, fibers, flyings

Protection against circulating dust, fibers, flyings, seepage

Every care has been taken to ensure the accuracy of the information contained in this publication. Due to Cemps policy of continuous development and improvement, the company reserves the right to supply products which may differ slightly from those illustrated and described in this publication. Descriptions and technical
features listed in this brochure may not be considered as binding. Under no circumstances should data in this publication be considered as a contractual obligation.

Note 8: Unless the explosion protection risk assessment states otherwise

Additional Market Access: IECEx Scheme

Manufacturers of Ex equipment can obtain certificates of conformity that will be accepted at a national level in all countries that participate in the IECEx Scheme.
A certificate of conformity may be obtained from any certification body accepted into the Scheme.
The certificate will attest that (1) the equipment design conforms to relevant IEC Standards and (2) the product is manufactured under a quality plan assessed by an Approved IECEx Certification Body (Ex CBs).
Manufacturers holding certificates of conformity may affix the IECEx Mark of Conformity to equipment they have verified complies with the certified design.

Cemp srl - Via Piemonte, 16 I 20030 Senago (MI) Italy

tel. +39 02 94435401 - fax +39 02 9989177 - cemp@cemp.eu - www.cemp.eu

Dust