ATEX/IECEx Markings and Zone Examples

In the marking string “II 2 G Ex d IIC T4 Gb,” what does the letter “G” indicate?

• Gas environment classification

• Grounding requirement for device

• General equipment category

• Group of notified bodies

In the same marking, what does “d” represent in “Ex d”?

• Intrinsic safety protection type

• Flameproof protection type

• Dust-tight protection type

• Pressurization protection type

What does “IIC” denote within the marking sequence?

• Inspection certificate code

• Ignition source category

• Ingress protection rating

• Gas group classification

Which element in “II 2 G Ex d IIC T4 Gb” corresponds to the temperature class?

• II equipment group

• Gb suffix indicator

• 2 equipment category

• T4 value entry

What does the suffix “Gb” specify at the end of the marking?

• Group B certification type

• Gas burning permit level

• Ground bonding requirement

• Equipment protection level

In hazardous area zoning for gas/vapor, Zone 0 corresponds to which condition?

• Occasional presence during normal operation

• Presence only in confined dust bins

• Continuous presence of explosive atmosphere

• Not likely present except abnormally

At a gas station, the area immediately around the fuel storage tank vent is most likely classified as which zone?

• Zone 0 gas area

• Zone 22 dust area

• Zone 1 gas area

• Zone 2 gas area

During decanting of flammable liquid from container to container, the surrounding area is typically which zone?

• Zone 0 gas area

• Zone 1 gas area

• Zone 21 dust area

• Zone 2 gas area

Which gas zone best fits an unvented garage pit where vapors may accumulate?

• Zone 2 intermittent vapors

• Zone 1 frequent vapors

• Zone 22 settled dusts

• Zone 0 continuous vapors

In dust environments, Zone 20 is typically associated with which location?

• Inside dust handling enclosures

• Open areas near silos

• Vent stacks outdoors

• Edges of loading platforms