1 Scope
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.
Separation elements are considered for both electrical and non-electrical equipment.
If mechanical energy can be transformed into a potential ignition source, additionally
an ignition hazard assessment in accordance with ISO 80079‑36 is performed and appropriate measures are undertaken. Suitable measures can be selected
from ISO 80079‑37 or IEC TS 60079‑42.
This document
also specifies requirements for the combination of two Types of Protection, each
with EPL Gb, to achieve EPL Ga. Examples are included in 4.2.
This document
supplements and modifies the general requirements of IEC 60079‑0. Where a requirement of this document conflicts with a requirement of IEC 60079‑0, the requirement of this document takes precedence.