7.2.2 - Bath and shower room requirements
for installations up to 1st january 2002

Usually, protection against direct contact will be by means of earthed equipotential bonding and automatic disconnection of the supply in the event of a fault (the same as for most other installations), and the special requirements are:

1. - where the plumbing in the bathroom has been carried out using metal pipes (usually of copper), all extraneous conductive parts must be bonded together and to earth with BS 951 clamps (see {Fig 7.2}), and with no exposed metallic conductors. The exception to this is any SELV system, which must remain unconnected to the main earthing system

Fig 7.1 - Permissible positions of switches and socket outlets
in a room containing a shower cubicle but no bath

Fig 7.2 - Bonding requirements for a bathroom with a metal pipe
plumbing system [601-04-02] - the line showing bonding
connections does not represent the actual positions of the cable

2. - where the plumbing in the bathroom has been carried out using plastic pipes there is no need for bonding at all other than to connect exposed metalwork of equipment such as luminaires, heaters and showers to earth. It is not necessary to bond exposed copper pipes provided that they are less then 0.5 m long.

3. - the earth fault loop impedance must be low enough to allow disconnection within 0.4 s (see {5.3}).

In no case within a bathroom is it permissible to rely for protection against direct contact on obstacles, placing out of reach, a non-conducting location or earth-free equipotential bonding. Switches must be out of reach of a person using the bath or shower, although cord-pull and similar remotely controlled switches may be used. There must be no switchgear, control gear or accessories installed within the bath or shower basin, whilst wiring must not be metallic sheathed, or enclosed in metallic conduit or trunking if run on the surface. The installation of equipment within a bath may sound ridiculous, but jacuzzi pumps and devices to assist disabled people to get into and out of a bath are not uncommon. Where, as is often the case, controls are mounted on the bath, the whole system must be fed at no more than 12 V.

Lampholders must be provided with a protective shield (see {Fig 6.11}) if within 2.5 m of the bath, or totally-enclosed luminaires must be used. Electrical equipment installed beneath a bath (an example is a jacuzzi pump) must only be accessible after the use of tools. If electric floor heating is used in a room containing a bath or a shower cubicle, it must have its metal sheath, or a covering metal grid if there is no metallic sheath, connected to the local equipotential bonding.

Guidance Note 7 makes it clear that before long bathrooms will be divided into zones (not unlike those for a swimming pool) with strict requirements for the ingress of water into equipment installed in these zones. The suggestion is based on Regulations already agreed by CENELEC but not yet accepted in the UK,