Extract from 17th Edition Electricity in Swimming Pools Regulations
BS7671
Effective from 1st June 2008
(Including additional explanatory diagrams)
STANDARD SWIMMING POOL
VOLUME
ZONE 2
VOLUME
ZONE 1
2.5m
VOLUME
ZONE 2
VOLUME
ZONE 0
1.5m
2m
2m
VOLUME
ZONE 0
Main Pool
Footbath
SWIMMING POOL WITH DIVING BOARDS OR RAISED PLATFORMS
1.5m
1.5m
2.5m
VOLUME
ZONE 2
VOLUME
ZONE 1
2.5m
VOLUME
ZONE 1
VOLUME
ZONE 2
VOLUME
ZONE 0
VOLUME
ZONE 0
1.5m
2m
2m
VOLUME
ZONE 0
1.5m
SWIMMING POOL WITH RAISED WALLS
VOLUME
ZONE 1
VOLUME
ZONE 2
2.5m
H
VOLUME ZONE 0
VOLUME
ZONE 0
1.5m
VOLUME
ZONE 2
2.5m
2m
H
2m
1.5m
Swimming pools and other basins (702)
This section applies to the basins of swimming pools, fountains, paddling pools and surrounding
zones. Special requirements may apply to medical pools. Swimming pools which are within the
scope of an equipment standard are outside the scope of BS 7671
When diving boards, springboards, starting blocks or a chute exist, then Zone 1 extends 1.5 m
from the edge of these items and 2.5 m above the highest surface expected to be occupied by a
person when using them.
Note; There is no Zone 2 for fountains.
Application of protective measures against electric shock
In Zone 0 only SELV (maximum voltage 12V a.c rms or 30V ripple-free d.c.) must be used and the
safety source must be outside Zones 0, 1 and 2. In Zone 1, only SELV (maximum voltage 25V a.c.
rms or 60V ripple-free d.c.) can be used with the safety source being outside Zones 0, 1 and 2.
Where electrical equipment is to be used in the interior of basins, which are intended for operation
only when people are not inside the basin, one or more of the following methods shall be used:
?? SELV with the supply source installed outside Zones 0, 1 and 2. If RCD protection in
accordance with Regulation 415.1.1 is provided for the supply circuit the supply source can
be installed in Zone 2
?? automatic disconnection of the supply using RCDs having characteristics according to
Regulation 415.1.1
?? electrical separation, in accordance with Section 413 for the supply source, to one item of
equipment installed outside Zones 0, 1 and 2. If RCD protection in accordance with
Regulation 415.1.1 is provided for the supply source, it can be installed in Zone 2.
Both the socket-outlet supplying such equipment and its control device must have a notice to warn
users that the equipment must not be used when persons are inside the basin.
When the supply to a swimming pool is TN-C-S it is recommended that an earth mat or earth
electrode be installed and conceded to the protective equipotential bonding of the installation. The
value should be 20 O or less.
The following protective measures must not be used in any zone:
?? obstacles
?? placing out of reach
?? non-conducting location
?? earth-free local equipotential bonding.
Additional protection using supplementary bonding
In Zones 0, 1 and 2 any extraneous-conductive-parts shall be connected by supplementary
bonding conductors to the protective conductors of exposed-conductive-parts of equipment in the
zones. Connection with protective conductors can be achieved in a local distribution board or
accessory in the proximity of the location.
Selection and erection of equipment
External influences
Equipment must have at least the following levels of protection:
??
??
??
??
??
Zone 0
Zone 1
Zone 2
Zone 2
Zone 2
IPX8
IPX4 (IPX5 where water jets are likely to be used for cleaning purposes)
IPX2 indoor locations
IPX4 outdoor locations
IPX5 locations where water jets are likely to be used for cleaning purposes.
Wiring systems
The following applies to surface wiring systems and those embedded in walls, ceilings or floors
when their depth is less than 50 mm.
?? Metallic sheath or coverings of wiring systems must always be connected to the
supplementary equipotential bonding of the installation (Zones 0, 1 and 2).
?? Cables should, where possible, be installed in PVC conduit (Zones 0, 1 and 2).
?? Wiring systems installed in Zones 0 and 1 shall only supply equipment in those zones.
Additional requirements for fountains
Electrical cables, which supply equipment in Zone 0, shall be installed outside the basin rim as far
away as possible and cable runs to equipment shall be kept short. In Zone 1 installed cables shall
have mechanical protection to AG2 and, if submersed in water to a depth AD8, cable type
H07RN8-F to BS 7919 is suitable. In the case where installation is to depths greater than 10 m,
cable manufacturers should be consulted.
Electric pumps shall comply with BS EN 60335-2-41
Junction box
ln Zones 0 or 1 a junction box shall not be installed. lf a SELV circuit is used, a junction box may
be installed in Zone 1 .
Switchgear, control gear and accessories
Switchgear, control gear and socket-outlets must not be installed in Zones 0 and 1
However, for swimming pools where it is not possible to locate socket-outlets or switches outside
of Zone 1, then socket-outlets and switches may be installed providing they have non-conductive
cover plates and are:
?? more than 1.25 m outside the border of Zone 0
?? at least 0.3 m above the floor
?? protected by an RCD or electrical separation (the safety isolating transformer being outside
Zones 0 and 1).
Other equipment
In Zones 0 and 1, only current-using equipment specifically for swimming pools is allowed to be
installed.
Underwater Iuminaires
Only fixed luminaries complying with BS EN 60958-2-18 shall be used if they are in contact with
water.
When underwater lighting is located behind watertight portholes, and they are serviced from
behind, they shall comply with the relevant part of BS EN 60598. Careful installation is required to
ensure there is no conductive connection between any exposed-conductive-part of the Iuminaire
and conductive parts of the porthole.
Special requirements for electrical equipment in Zone 1
For filtration systems, jet stream pumps or other equipment, designed to be fixed in a swimming
pool or other basin, in Zone 1 the equipment shall:
?? be within an insulating enclosure Class II or equivalent insulation with mechanical impact
protection (AG2) medium severity
?? only be accessible via a door or hatch using a key or tool. Opening of the door or hatch
shall disconnect all live conductors. Supply cables and the main means of disconnection
shall be to Class II or equivalent insulation
?? have a supply circuit protected by the three methods specified on page 7/9 for application of
protective measures against electric shock.
Where swimming pools have no Zone 2, lighting equipment supplied by other than a SELV source
at 12 V a.c. rms or 30 V ripple-free d.c. can be installed on a wall or ceiling in Zone 1 , provided
that:
?? the circuit is protected by automatic disconnection and RCD protection is provided in
accordance with Regulation 415. 1 .1
?? equipment must be at least 2 m above the lower limit of Zone 1.
Premier Solutions (Nottingham) Ltd.
11 Ascot Park Estate, Lenton Street, Sandiacre, Nottingham NG10 5DJ Tel: 0115 9394122
www.premier-solutions.biz