ATEX LABELLING: GROUPS AND CATEGORIES OF APPLIANCES
The ATEX labels are affixed to electrical and industrial equipments used in environments with risk of fire and explosion to describe their correct scope of use.
For those working in hazardous environments, understanding ATEX labels is useful for choosing the right equipments and reducing risks.
ATEX standards are defined by the Directive 2014/34/EU. This Directive divides the equipments and protection systems in groups according to their use:
- Group I: equipment intended for use in mines and firedampEquipment group I equipment: intended for use in mines with grisou gas
- Group II: equipment intended for use in explosive atmosphere on the surface (i.e., in industrial plants where flammable gases such as methane or hydrogen are used)
Each group is subdivided into categories as shown in the following tables:
Group I |
||
Category |
Protection level |
Operating conditions |
M1 |
Very high Two means of protection Two failures expected |
Powered in case of an explosive atmosphere |
M2 |
Elevato Guaranteed in normal and heavy-duty operations |
Not powered in case of an explosive atmosphere |
Table 1 - Categories of equipment in Group I
Group II |
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Category |
Protection level |
Presence and duration of a dangerous atmosphere |
ZONE |
|
GAS |
DUST |
|||
1 |
Very high Two means of protection Two failures expected |
Always, often or for long periods |
0 |
20 |
2 |
High A means of protection A breakdown is expected |
Likely |
1 |
21 |
3 |
Normal Guaranteed in standard operation |
Unlikely |
2 |
22 |
Table 2 - Categories of equipment in Group II
It is necessary to add the letters G and D to the Category number according to the presence of Gas or Dust and depending if the explosive atmosphereis due to gas or dust (both letters can be used at the same time when the equipment is suitabl for both gas and dust).
As it can be inferred, there is a direct correspondece among Directive defined Groups and Categories and among protection levels and hazardous areas.
Correspondence between Groups/Categories and EPL |
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IEC/EN 60079 |
ATEX 2014/34/UE |
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Group |
Atmosphere |
EPL |
Protection Level |
Group and Category |
Zone |
Group I |
Mining firedamp |
Ma |
Very high |
I M1 |
/ |
Mb |
High |
I M2 |
/ |
||
Group II |
GAS (IIA IIB IIC) |
Ga |
Very high |
II 1G |
Zone 0 |
Gb |
High |
II 2G |
Zone 1 |
||
Gc |
Normal |
II 3G |
Zone 2 |
||
Group III |
DUST (IIIA IIIB IIIC) |
Da |
Very high |
II 1D |
Zone 20 |
Db |
High |
II 2D |
Zone 21 |
||
Dc |
Normal |
II 3D |
Zone 22 |
Table 3 - correspondence between Groups/Categories and EPL
ATEX LABELLING
The label that responds solely and exclusively to the prerequisites of the ATEX Directive must strictly contain the following information:
- CE marking;
- Identification number of the Notified Body that assesses the quality system of the ATEX production (i.e., 0051 is the identification number of IMQ);
- the epsilon-x (Ex) marking/trademark;
- the equipment Group and Category followed by the letter D (dust) or the letter G (gas);
Further to the information required by the Directive, the label contains additional technical information such as: type of protection, the Gas or Dust group, the Gas temperature class or the maximum surface temperature for dust and the protection level.
Example:
ATEX MARKING: MANUFACTURER'S DATA
The ATEX labels must contain information about the manufacturer of the equipment.
Manufacturer data:
- Name and address of the manufacturer;
- Product part number;
- Number of the EU/EC-type-examination certificate;
- Batch identification number (serial number or week/year of production);
- Technical nameplate characterizing the product (voltage, frequency, current, polarity, IP rate, insulation class, particular operating temperature, etc.);
Example of ATEX label: