Ex-pert Electrical Perspective

A Dynamic academic elaboration on the Art & Science of Hazardous Area Protection

Equipment Protection Level

Level of protection assigned to equipment based on its likelihood of becoming a source of ignition and distinguishing the differences between explosive gas atmospheres, explosive dust atmospheres, and the explosive atmospheres in mines susceptible to firedamp.

The term EPL was coined in IEC 60079-17-2007.

Previously Area Classification and Device Category were related as follows:

ZONE Device Category
0 1 G
1 2G
2 3G

In order to relate the basic suitability of an apparatus for a specific zone, EPL of the device is stated. (Device Category 1 2 & 3 have been replace by letters ‘a’, ‘b’ & ‘c’)

Zone EPL  
0 Ga (GAS)
1 Gb (GAS)
2 Gc (GAS)
20 Da (DUST)
21 Db (DUST)
22 Dc (DUST)

Thus a device with following marking  is ‘read’ in the following way:

    cropped-ex_logo_1.jpg    II2G    Ex d[ia]IIC        T6 db

The Ex Logo with roman II indicates the ATEX part of the marking.

Roman II indicate that the equipment is for the ‘above-surface ‘other than the mines installation areas.

2G is the rating of the area of use. (Previously referred to as : Device Category)

Ex d [ia] is the type of protection incorporated in the equipment by the manufacturer

IIC is the group (Gas)

T6 is the maximum surface temperature of the equipment during operation

‘db is the Equipment protection level.

(More on this in : Reading an Ex Label)

(main)

Link to Hazardex : A multi-media brand providing key information, topical discussion and community networking for process safety-related topics to the global hazardous area industry.
Link to IndEx: Owner’s Engineering, Ex Product Certification, E-Learning and Training, Asset Digitization Solutions, Area Classification, Ex Audits & Inspections

IndEx