Code of Practice for the Electricity (Wiring) Regulations - 2009 Edition

• SELV, the source for SELV being installed outside Zones 0, 1 and
2. However, it is permitted to install the source for SELV in Zone
2 if its supply circuit is protected by an RCD having the
characteristics specified in Code 11J;
• Automatic disconnection of supply, using an RCD having the
characteristics specified in Code 11J;
• Electrical separation, the source for electrical separation supplying
only one item of current using equipment and being installed
outside Zones 0, 1 and 2. However, it is permitted to install the
source in Zone 2 if its supply circuit is protected by an RCD having
the characteristics specified in Code 11J.
(5) Selection and erection of equipment
(a) Degree of protection of enclosures
Equipment should have the following minimum degrees of
protection or equivalent:
(i) in Zone 0 – IPX8
(ii) in Zone 1 – IPX4
– IPX5 where water jets are likely to occur for
cleaning purposes
(iii) in Zone 2 – IPX2 for indoor locations
– IPX4 for outdoor locations
– IPX5 where water jets are likely to occur for
cleaning purposes.
(b) Wiring systems
(i) In Zones 0, 1 and 2, any metallic sheath or metallic covering of
a wiring system should be connected to the supplementary
equipotential bonding. Cables should preferably be installed in
conduits made of insulating material.
(ii) In Zones 0 and 1, a wiring system should be limited to that
necessary to supply equipment situated in these Zones.
(iii) Junction box should not be installed in Zones 0 and 1, but in
case of SELV circuits it is permitted to install junction boxes in
Zone 1.
(c) Switchgear and controlgear
(i) In Zones 0 and 1, switchgear or controlgear should not be
installed.
(ii) In Zones 0 or 1, a socket outlet should not be installed.
(iii) In Zone 2, a socket outlet or a switch is permitted only if the
supply circuit is protected by one of the following protective
measures:
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