Along with rigid metal conduit there are a number of cable types which are approved for use in these hazardous locations.
Cable used in explosion proof wiring.
In europe and elsewhere suitably rated cable is connected directly to the equipment using certified flame proof cable glands.
In north america metal conduit must be used for field wiring.
Ex ia ex ib intrinsically safe cable glands designed in such a way that the energy of any spark is lower than that can ignite a flammable mixture.
So cable glands and seals may need to be considered but they are of lighter construction as they are not required to cool exploding gases only to prevent the flow of gases.
Tmc2x cable connector for armoured cables 0 50 hub size aluminum 0 69 0 99 csa.
The permissible wiring methods are selected by the code making panel with safety being the most critical consideration.
Flameproof explosion proof protection methods.
Imposes strict requirements for wiring methods in these locations.
If heat or sparks from faulty equipment within the enclosure ignite flammable gas present with it the resulting explosion is contained within the enclosure.
Ia is designed to a higher integrity and can be used in zone 0 hazardous area locations whereas ib is only suitable for zone 1 2 locations.