This part of IEC 60079 specifies requirements for construction, testing and marking for Ex Equipment that contains parts of the equipment with different Equipment Protection Levels (EPLs) and a separation element. This equipment is mounted across a boundary where different EPLs are required, for example between different gas hazardous areas, dust hazardous areas or gas hazardous areas adjacent to dust hazardous areas.
EXAMPLE: Equipment installed in the wall of storage tanks located in Zone 1 and containing Zone 0 inside.
