Specification 034

Electrical Installations

DEFENCE ESTATES
MINISTRY OF DEFENCE

Edition 1 - 2004
Specification 034

Electrical Installations

Spec 034 -formerly PSA Standard Specification (M&E) No 1

DEFENCE ESTATES
MINISTRY OF DEFENCE
Edition 1 - 2004
 No Warranty is given as to the accuracy of this Specification or its fitness for purpose.

Ministry of Defence Copyright

Applications for reproduction should be made to Defence Estates

© crown copyright 2004

Updated to include new references, current technology, materials and working practices.

Prepared by Defence Estates

Edition 1-2004
Specification 034

Contents

Page

CONTENTS i

TABLES v

FOREWORD vi

ABBREVIATIONS vii

SECTION ONE - GENERAL REQUIREMENTS 1

1.1 EXTENT OF WORK 1
1.2 RELATED DOCUMENTS 1
1.3 DEFINITIONS 1
1.4 REGULATIONS 2
1.5 STANDARDS 2
1.6 APPROVAL 2

SECTION TWO - POWER DISTRIBUTION EQUIPMENT 3

2.1 ELECTRICAL CHARACTERISTICS OF ASSEMBLIES 3
2.2 ENCLOSURES OF ASSEMBLIES 3
2.3 BUSBAR TRUNKING SYSTEMS 3
2.4 DISTRIBUTION BOARDS 4
2.5 AIR-BREAK SWITCHES 4
2.6 MOULDED-CASE CIRCUIT-BREAKERS 4
2.7 FUSES 4
2.8 MINIATURE CIRCUIT-BREAKERS 5
2.9 RESIDUAL CURRENT-OPERATED CIRCUIT-BREAKERS 5
2.10 CONTACTORS 5
2.11 FRAMEWORK 5
2.12 ERECTION 5
2.13 MARKING AND NOTICES 6

SECTION THREE - POWER DISTRIBUTION CABLES 7

3.1 CABLES 7
3.2 JOINTING AND TERMINATING CABLES 7
3.3 CONNECTING AND TERMINATING CONDUCTORS 8
3.4 SLEEVES, TAPES AND SEALING COMPOUNDS 8
3.5 JOINTING PAPER-INSULATED CABLES 8
3.6 TERMINATING PAPER-INSULATED CABLES 9
3.7 JOINTING AND TERMINATING THERMOSETTING
AND THERMOPLASTIC (PVC) INSULATED CABLES 9
3.8 JOINTING CNE CABLES 9
3.9 JOINTING DISSIMILAR CABLES 9
3.10 STOP ENDS 10

SECTION FOUR - ALARM, CONTROL, COMMUNICATION AND MONITORING CABLES 11

4.1 CABLES 11
4.2 JOINTS AND TERMINATIONS 11
4.3 JOINTING THERMOSETTING (POLYETHYLENE) -INSULATED CABLES 11
4.4 TERMINATING THERMOSETTING (POLYETHYLENE) -INSULATED CABLES 11
4.5 JOINTING THERMOSETTING (POLYETHYLENE)-INSULATED CABLES TO PAPER-
INSULATED CABLES 11
4.6 SEGREGATION 12

Edition 1-2004 i
 Specification034

4.7 MARKING 12

SECTION FIVE - CABLE SUPPORTS 13

5.1 SELECTION OF CABLE SUPPORTS 13
5.2 PROTECTIVE FINISHES FOR FERROUS MATERIALS 13
5.3 CABLE TRAY 13
5.4 CABLE CLEATS 14
5.5 CABLE RACKS AND CABLE LADDERS 14
5.6 CABLE HANGERS 14
5.7 SUSPENSION AND FIXINGS 14
5.8 BONDING 14

SECTION SIX - CABLE INSTALLATION 17

6.1 ROUTES 17
6.2 SEGREGATION 17
6.3 SUPPORTS AND FIXINGS 17
6.4 TRENCHING 17
6.5 WARNING TAPES AND COVERS 18
6.6 DUCTS 18
6.7 LAYING OF DUCTS 19
6.8 HANDLING OF CABLES 19
6.9 SEALING DUCTS AND OPENINGS 20
6.10 CABLE GUARDS 20
6.11 MARKING OF CABLES 20
6.12 REDUNDANT CABLES 21

SECTION SEVEN - OVERHEAD LINES 23

7.1 OVERHEAD LINES 23
7.2 CONNECTIONS TO BUILDINGS 23
7.3 CATENARY WIRE SUPPORTS 23

SECTION EIGHT - WIRING SYSTEM: CABLES IN CONDUIT, TRUNKING AND DUCTING 25

8.1 CABLES 25
8.2 CONDUIT 25
8.3 STEEL CONDUIT AND FITTINGS 25
8.4 NON-METALLIC CONDUIT 25
8.5 TRUNKING AND DUCTING 25
8.6 STEEL TRUNKING 26
8.7 UNDERFLOOR DUCTING AND FLOOR TRUNKING 26
8.8 ROUTES AND SEGREGATION 26
8.9 SUPPORTS AND FIXINGS 26
8.10 INSTALLATION 27
8.11 PROTECTIVE CONDUCTOR 28
8.12 WIRING 28
8.13 MITIGATION OF PLASTICISER FROM THERMOPLASTIC (PVC) MATERIALS 28

SECTION NINE - WIRING SYSTEM: MULTI-CORE SHEATHED CABLES 30

9.1 CABLES 30
92 BOXES 30
9.3 ROUTES AND SEGREGATION 30
9.4 INSTALLATION 30
9.5 PREFABRICATED WIRING INSTALLATIONS 31

SECTION TEN - WIRING SYSTEM: MINERAL-INSULATED CABLES 33

10.1 CABLES 33
10.2 TERMINATION 33
10.3 JOINTS 34
10.4 ROUTES AND SEGREGATION 34
10.5 SUPPORTS AND FIXINGS 34
10.6 INSTALLATION 34

SECTION ELEVEN - EARTHING 37

11.1 MATERIALS 37
11.2 EARTH ELECTRODES 37
11.3 CONDUCTORS 37

ii Edition 1-2004
Specification 034

11.4 JOINTS AND CONNECTIONS 37

11.5 INSPECTION PITS 38
11.6 SUPPORTS AND FIXINGS 38
11.7 INSTALLATION 38
11.8 BONDING TO INCOMING SERVICES 38

SECTION TWELVE - WIRING ACCESSORIES AND SMALL EQUIPMENT 39

12.1 ACCESSORIES-GENERAL 39
12.2 SWITCHES 39
12.3 DIMMERS 39
12.4 SOCKET OUTLETS 40
12.5 SOCKET OUTLETS FOR WET LOCATIONS 40
12.6 PLUGS 40
12.7 SHAVER SOCKET OUTLETS 40
12.8 FUSED CONNECTION UNITS 40
12.9 COOKER CONTROL UNITS 40
12.10 TELEPHONE CORD-OUTLETS 40
12.11 SAFETY ISOLATING TRANSFORMERS 40
12.12 ROOM THERMOSTATS 41
12.13 ELECTRICITY METERS 41
12.14 TIME SWITCHES 41
12.15 PHOTO-ELECTRIC CONTROL UNITS 41
12.16 BELLS AND BUZZERS 41
12.17 PUSHES 41
12.18 INDICATORS 41
12.19 TERMINAL BLOCKS 41
12.20 MOUNTING HEIGHTS 41

SECTION THIRTEEN - CONNECTIONS TO APPLIANCES AND MOTORS 45

13.1 GENERAL 45
13.2 FLEXIBLE CORDS 45
13.3 WATER HEATERS 45
13.4 ROOM HEATERS 45
13.5 TOWEL RAILS 45
13.6 COOKERS 45
13.7 WASTE DISPOSAL UNITS (DOMESTIC) 45
13.8 SANITARY DISPOSAL UNITS 46
13.9 EXTRACT FANS 46
13.10 OTHER APPLIANCES 46
13.11 PLANT, MACHINERY AND MOTORS 46

SECTION FOURTEEN - LUMINAIRES AND LAMPS 49

14.1 LUMINAIRES 49
14.2 STREET LIGHTING COLUMNS 49
14.3 LAMPS 49
14.4 LAMPHOLDERS 49
14.5 CEILING ROSES 49
14.6 PENDANTS AND CHAIN SUSPENSIONS 50
14.7 SUPPORTS AND FIXINGS 50
14.8 WIRING CONNECTIONS 50

SECTION FIFTEEN - EMERGENCY LIGHTING 53

15.1 GENERAL 53
15.2 CENTRAL BATTERIES 53
15.3 CENTRAL BATTERY CONTROL EQUIPMENT 53
15.4 WIRING 53

SECTION SIXTEEN - POTENTIALLY EXPLOSIVE ATMOSPHERES 55

16.1 STANDARDS AND CODES OF PRACTICE 55
16.2 MINISTRY OF DEFENCE MILITARY EXPLOSIVES AREAS 55

SECTION SEVENTEEN - LIGHTNING PROTECTION OF BUILDINGS 57

17.1 GENERAL 57
17.2 AIR TERMINATIONS 57

Edition 1-2004 i ii
 Specification 034

17.3 DOWN CONDUCTORS 57

17.4 JOINTS 57
17.5 EARTH ELECTRODES 58
17.6 FIXINGS 58

SECTION EIGHTEEN - CATHODIC PROTECTION 59

18.1 GENERAL 59
18.2 GROUNDBEDS 59
18.3 SOURCE OF POWER 59
18.4 CABLING 59
18.5 TEST POINTS AND BONDING 60
18.6 MARKING 60

SECTION NINETEEN - INSPECTION AND TESTING 61

19.1 GENERAL 61
19.2 INFORMATION 61
19.3 TESTING METHODS 61
19.4 POWER CABLES 61
19.5 ALARM, CONTROL, COMMUNICATION AND MONITORING CABLES 61
19.6 CONDUIT AND TRUNKING 61
19.7 EARTH ELECTRODES 61
19.8 LIGHTNING PROTECTION 62
19.9 EARTH FAULT LOOP IMPEDANCES 62
19.10 EMERGENCY LIGHTING SYSTEMS 62
19.11 POTENTIALLY EXPLOSIVE ATMOSPHERES 62
19.12 CATHODIC PROTECTION 62
19.13 RECORDS AND CERTIFICATES 62

SECTION TWENTY - DRAWINGS AND DOCUMENTS BY CONTRACTOR 63

20.1 EXTENT OF PROVISION 63
20.2 INSTALLATION DRAWINGS AND DOCUMENTS 63
20.3 BUILDER'S WORK DRAWINGS 63
20.4 AS-INSTALLED DRAWINGS 63
20.5 MAINTENANCE AND OPERATING INSTRUCTIONS 64

APPENDIX ONE - LIST OF STANDARDS 67

iv Edition 1-200
4
Specification 034

Tables

TABLE 5A FIXING FOR CABLE SUPPORTS 15

TABLE 6A MINIMUM SPACING OF CABLES 22

TABLE 6B MINIMUM COVER FOR CABLES 22

TABLE 8A CONDUIT AND TRUNKING FIXINGS 29

TABLE 8B PLASTERCISER MITIGATION 29

TABLE 10A MINERAL-INSULATED CABLE SHEATH COLOURS 35

TABLE 10B MINERAL-INSULATED CABLE FIXINGS 35

TABLE 12A MOUNTING HEIGHTS (FOR ACCESSORIES AND EQUIPMENT) 43

TABLE 13A CONNECTIONS TO APPLIANCES 47

TABLE 14A LAMPHOLDERS 51

TABLE 17A CONDUCTOR FIXINGS (LIGHTNING PROTECTION) 58

Edition 1-2004 v
 Specification 034

Foreword

1. This Specification is one of a series prepared by Defence Estates (DE) an

agency of the Ministry of Defence (MOD) primarily for use in its contracts for
mechanical and electrical engineering works. The Specification covers
electrical installations for buildings other than dwellings. It is a revision of the
former Property Sevices Agency (PSA) Standard Specification (M&E) No.l,
dated 1985.

2. When this Specification is used in connection with a defence contract then it is

to be read in conjunction with such further documents setting out contractual
requirements particular to the contract. Where the words "as indicated",
"where indicated" or "unless otherwise indicated" are included in the text, it is
the designer/specifiers responsibility to ensure that the information referred to is
included in the documentation package. (See clause 1.3.3).

3. Whilst this Specification was written by DE for use on MOD contracts, it is

acknowledged that it could be usefully applied to other contracts. DE
commends its use to other Government Departments. It may, therefore, be used
outside the MOD Estate. However, no warranty is given as to the accuracy of
this Specification or its fitness for any purpose.

4. This update includes modifications taking account of the 16th Edition of the
Wiring Regulations, now British Standard (BS) 7671:2001 Amendment No. 1,
2002 (AMD 13628) and the IEE Guidance Notes issued alongside. The
opportunity has been taken to update various references to other standards. It is
recognised that electrical engineering standards are rapidly changing, with many
BS EN series standards replacing older BS standards. Standards current at the
time of contract should be assumed to be appropriate. Other updates have taken
account of new materials and equipment coming into use since the last issue,
and minor corrections have been made. (A major review of the scope and
content has not been attempted at this time.)

5. It should be noted that this document now excludes fire alarm and detection
systems and Aviation Ground Lighting installations.

6. Compliance with the contents of this document will not in itself confer
immunity from legal obligations.

7. These specifications have been devised for the use of the Crown and its
contractors in the execution of contracts for the Crown. The Crown hereby
excludes all liability (other than liability for death or personal injury)
whatsoever and however arising (including, but without limitation, negligence
on the part of the Crown, its servants or agents) for any loss or damage however
caused where the Standard is used for any other purpose.

8. Compliance with a DE functional standard does not of itself confer immunity

from legal obligations.

vi Edition 1-2004
Specification 034

Abbreviations

The following abbreviations are used in this specification:

ac alternating current
BSRIA Building Services Research and Information Association
BS British Standard
BS EN British Standard Euro Norm
CNE Combined Neutral and Earth
COSHH Control of Substances Hazardous to Health
CPC Circuit Protective Conductor
dc direct current
DE Defence Estates
ELV Extra low voltage
EPR Ethylene propylene rubber
ESI Electricity Supply Industry
GLS General lighting service
GRP Glass Reinforced Plastic
HOFR Heat and oil resistant and flame retardant
HV High Voltage
ICEL Industry Committee for Emergency Lighting
IDMT Inverse Definite Minimum Time
IEE Institution of Electrical Engineers
IP Ingress Protection as defined in BS EN 60529
LDU Link disconnecting unit
LSF Low smoke and fume
LV Low Voltage
MCB Miniature circuit-breaker
MOD Ministry of Defence
PVC Polyvinyl chloride
RCCB Residual current operated circuit breaker without integrated
overcurrent protection
RCBO Residual current operated circuit breaker with integrated
overcurrent protection
XLPE Cross-linked polyethylene

Edition 1-2004 vi i
Specification 034

Section One - General Requirements

1.1 EXTENT OF WORK 1.1.8 Adequate protection of equipment during

transit shall be provided by Manufacturers and the
1.1.1 This Specification states the requirements Contractor shall ensure adequate protection on site.
for the supplying, assembling, fixing in position, The Contractor shall advise the Project Manager of
connecting, inspecting, testing and leaving in any damage that occurs to equipment including
working order, new, modified or additional finishes and shall carry out repairs as directed by the
electrical installations. Project Manager.

1.1.2 The work shall comprise the whole of the

labour and, unless otherwise indicated, all the 1.2 RELATED DOCUMENTS
materials necessary to form a complete installation,
including such tests, adjustments and 1.2.1 Related documents will be enumerated in
commissioning as are prescribed in subsequent the invitation to tender or in an appendix to the
clauses and as may otherwise be required to give an "particular clauses". They will include the
effective working installation to the satisfaction of conditions of contract, particular clauses and any
the Project Manager. supplementary specifications, schedules and
drawings that relate to the contract.
1.1.3 The words "complete installation" in
clauses 1.1.2 and 1.5.1 shall mean not only the items 1.2.2 If any discrepancy is found between this
of electrical equipment conveyed by this Specification and the related documents, regulations
Specification, but all the incidental sundry or standards, the appropriate Officer shall be
components necessary for the complete execution of informed. During the tender stage and prior to a
the works and for the proper operation of the contract being placed the Officer shall be as listed in
installation, whether or not these sundry components the documents; thereafter the Project Manager shall
are mentioned in detail in the tender documents be consulted.
issued in connection with the contract.

1.1.4 Items listed in the contract documents or 1.3 DEFINITIONS

otherwise indicated will be supplied to the
Contractor. 1.3.1 The definitions in BS 7671:2001 apply
throughout this Specification.
1.1.5 Unless otherwise indicated, work external
to buildings shall include the supply and installation 1.3.2 Where work is undertaken as a
of: Subcontract, "Contractor" shall mean
• sand for cable bedding and cover "Subcontractor".
• cable warning covers, cable warning tapes and
cable markers 1.3.3 The words "as indicated", "where
• poles/posts. indicated", "unless otherwise indicated", refer to
items or requirements indicated elsewhere in the
1.1.6 Unless otherwise indicated, the following tender documents issued in connection with the
will be carried out by others: contract, for example on a drawing, in a
• trenching, hole digging and backfilling supplementary specification or schedule.
• duct laying and construction of cable drawpits
• builders work. 1.3.4 "Project Manager" shall mean an official
of the MOD or commercial representative
1.1.7 Drawings and documents shall be responsible for the purpose of management and
provided by the Contractor in accordance with administration of the works covered within this
Section 20. Specification.

Edition 1-2004 1
Specification 034 Section One - General Requirements

1.3.5 The Project Manager shall, where 1.5 STANDARDS

required, consult with competent persons to ensure
that deviations from specification are satisfactory. 1.5.1 The complete installation shall comply
Alternatives may be used with the specific written with all relevant British Standards and, where
approval of the Project Manager. indicated, with other Standards and Specifications,
and all amendments thereto. The relevant issues
shall be those current three months before the date
1.4 REGULATIONS for return of tender, unless alternative dates are
indicated.
1.4.1 Each installation shall comply with all
relevant statutory instruments and regulations 1.5.2 Where practicable, each item of
including, but not limited to, the following: equipment shall be clearly and indelibly marked to
• Electricity at Work Regulations 1989 indicate the standard with which it complies.
• Electricity Supply Regulations 1988 Alternatively a Certificate of Compliance shall be
• Health and Safety at Work etc. Act 1974 provided for the Project Manager, to be included in
• Construction (Design and Management) the handover documentation.
Regulations 1994
• BS 7671:2001 Requirements for Electrical 1.5.3 Where equipment or services are
Installations indicated to be manufactured or provided under a
• requirements of the local electricity, particular certification, licensing or quality
telecommunications, gas and water Suppliers; assurance scheme, the Manufacturer or Supplier
• COSHH Regulations 2002 shall be a current participant in the relevant scheme.
• Construction (Working Places) Regulations A Certificate of Compliance shall be provided for
1966 the Project Manager, to be included in the handover
• Dangerous Substances and Explosive documentation
Atmospheres Regulations 2002 (DSEAR)
• Electrical safety quality and continuity 1.5.4 Equipment supplied shall be of a standard
regulations 2002. that ensures its compliance with all appropriate
British Standards and EU requirements.
EU Directives implemented into British regulations.

In addition the guidance published in the Institution 1.6 APPROVAL

of Electrical Engineers (IEE) Guidance Notes shall
be followed. 1.6.1 The Project Manager's approval shall not
relieve the Contractor of his contractual
1.4.2 The Contractor shall fulfil the relevant responsibilities and obligations. The Contractor
duties under the Construction (Design and shall be responsible for discrepancies, errors or
Management) Regulations as Principal Contractor or omissions on drawings or other documentation
shall co-ordinate with the Principal Contractor as supplied by him, whether they have been approved
appropriate. by the Project Manager or not, provided such
discrepancies, errors or omissions are not due to
incorrect information given in writing by the Project
Manager. The Contractor shall be responsible for
ensuring that equipment complies with the specified
requirements.

2 Edition 1-200 4
Specification 034

Section Two - Power Distribution Equipment

2.1 ELECTRICAL CHARACTERISTICS OF 2.2.6 Ferrous parts of enclosures located outside

ASSEMBLIES buildings or at other locations, as indicated, shall be
protected against corrosion by a hot-dip galvanised
2.1.1 The electrical characteristics of coating to BS EN ISO 1461 or by a zinc sprayed
component parts of assemblies shall apply when the coating to BS EN 22063 with the Manufacturer's
components are mounted in their enclosures, standard finish or as indicated.
appropriate derating factors having been allowed for
the effect of the enclosures, other components and 2.2.7 The resins and dyes used in the
interconnections. manufacture of Glass Reinforced Plastic (GRP)
enclosures shall be able to withstand continuously a
2.1.2 Site built assemblies shall not be allowed temperature of 50°C.
except with the express written approval of the
Project Manager. 2.2.8 The minimum acceptable degree of
ingress protection (IP) from all directions of the
installed assembly shall be as indicated.
2.2 ENCLOSURES OF ASSEMBLIES

2.2.1 Doors shall have fastenings with provision 2.3 BUSBAR TRUNKING SYSTEMS
for locking in the closed position, or shall require a
special tool for opening. 2.3.1 Busbar trunking systems shall comply
with BS EN 60439-2 and clauses 2.1 and 2.2. They
2.2.2 Fixing holes for equipment inside shall have a fault withstand current as indicated.
buildings may be inside or outside the enclosure.
Equipment to be located outside buildings shall have 2.3.2 Busbar trunking systems shall be suitable
fixing lugs external to the enclosure. for mechanical loads as defined in BS EN 60439-2,
and they shall not be used to support other
2.2.3 Earthing terminals shall be appropriately equipment.
fitted to each enclosure, suitable for internal and
external connection, to enable the exposed 2.3.3 A means of isolation shall be provided;
conductive parts of the factory built assembly to be the number of poles shall be as indicated.
connected to a protective conductor. Where the
enclosure has a painted finish, provision shall be 2.3.4 The phase sequence shall be maintained
made for the earthing terminal to be electrically along the entire length of each busbar trunking
connected to the enclosure without the need to system and shall be identical in all systems in the
remove any paint from ferrous metal. installation. Phase colour shall be clearly and
permanently marked in each trunking unit.
2.2.4 Adequate spacing shall be allowed for
spreading of cable tails to avoid stress on the 2.3.5 Conductors shall be supported by high
insulation or terminals; if necessary, proprietary grade non-hygroscopic and non-tracking insulating
extension boxes shall be fitted to standard material. They shall be anchored in at least one
enclosures. position and a means of taking up expansion and
contraction incorporated.
2.2.5 Gland plates shall be provided as
appropriate for the type of cable to be connected. 2.3.6 Tap-off points, where indicated, shall be
For single-core cables, non-ferrous gland plates shall provided with covers or shutters to screen entry to
be provided, and there shall be a clearance of not live conductors when the position is not occupied
less than 25mm between cable glands and ferrous with a tap-off unit. Tap-off units shall be provided
metal. as indicated.

Edition 1-2004 3
Specification 34 Section Two - Power Distribution Equipment

2.3.7 Where the enclosure is of metal it shall be 2.5.1 Air-break switches shall comply with BS
continuously connected and bonded as an exposed EN 60947-3 and clause 2.1 and have a utilisation
conductive part. An earth continuity conductor shall category of AC-22 or AC-23 as indicated. Other
be provided and bonded to an earthing terminal characteristics of the equipment shall be as
fitted to each trunking unit forming the system and indicated.
to the protective conductor of the incoming cable at
the feeder unit. 2.5.2 All switches including fuse combination
units shall meet the requirements for switch-
2.3.8 The length of busbar trunking systems disconnectors.
shall be determined from drawings for tender
purposes, but all measurements shall be checked on 2.5.3 Switches used as motor starters shall be to
site prior to manufacture or installation. Appendix A of BS EN 60947-3.

2.5.4 Operating mechanisms shall be

2.4 DISTRIBUTION BOARDS independent manual or as indicated.

2.4.1 Fuseboards and miniature circuit-breaker 2.5.5 Where indicated auxiliary contacts shall
boards shall comply with BS EN 60439-3 and be incorporated in switches.
clauses 2.1 and 2.2. Fuses and miniature circuit
breakers shall comply with clauses 2.7 and 2.8 and 2.5.6 Each switch shall have a facility for
shall be as indicated. padlocking in the "OFF" position.

2.4.2 Fuseboards shall be shielded or shrouded 2.5.7 Fuse combination units shall be fitted with
to meet at least IP2X standard. fuses complying with clause 2.7.3.

2.4.3 In distribution boards neutral busbars and 2.5.8 Enclosures shall comply with clause 2.2.
earth bars shall have at least one outgoing terminal
for each outgoing circuit. Consideration of the 2.6 MOULDED-CASE CIRCUIT-BREAKERS
requirements for high leakage current installations
shall be given. 2.6.1 Moulded-case circuit breakers shall
comply with BS EN 60947-2 and clause 2.1. They
shall have the voltage and current ratings, rated duty
2.4.4 A multi-terminal bar for the circuit
and rated short-circuit breaking capacity as
protective conductors shall be provided for both
indicated. The rated short-time withstand time shall
insulated and metal cased distribution boards. It
be one second unless otherwise indicated.
shall be directly connected to the earthing terminal
without dependence on the exposed conductive parts
of the enclosure. 2.6.2 MCCBs shall be of the independent
manual closing air-break type, rated for an
uninterrupted duty, unless otherwise indicated.
2.4.5 Identification of each fuseway and
Miniature Circuit Breaker (MCB) way shall be by
2.6.3 Auxiliary facilities, including power
permanent numbering. Identification on the neutral
closing and undervoltage releases, shall be provided
busbar and protective conductor bar shall clearly
only as indicated.
relate each terminal to its respective fuseway or
MCB way.
2.6.4 Each MCCB shall have a facility for
padlocking in the "OFF" position.
2.4.6 10% spare fuseways or MCB ways shall
be provided unless otherwise indicated. Where
2.6.5 Enclosures shall comply with clause 2.2.
specific ratings are indicated, fuses or MCB's shall
be incorporated, otherwise the ways shall be
provided with proprietary covers suitable for future
2.7 FUSES
additions.
2.7.1 The type and current rating of fuses shall
2.4.7 Each distribution board shall be fitted
be as indicated.
with a means of isolation.
2.7.2 Cartridge fuse links complying with BS
1361 shall be Type I. Fuse carriers, bases and
2.5 AIR-BREAK SWITCHES associated parts shall also comply with BS 1361.

4 Edition 1-200 4
Specification 034 Section Two - Power Distribution Equipment

2.7.3 Cartridge fuse links complying with BS 4345 and BS EN 10025, 10113, 10130, 10131 or
88/BS EN 60269 shall be Class gG (or Class gM in 10149 as appropriate. Metal-arc welding shall
motor circuits) unless otherwise indicated. Motor comply with BS EN 1011.
circuit fuse links shall be used only where indicated.
Fuse carriers, bases and associated parts shall also 2.11.2 Frameworks mounted within a building
comply with BS 88. shall have a galvanised finish with a coating
equivalent to, and not less than, type Z275 to BS EN
10147, but Manufacturers' standard finishes will be
2.8 MINIATURE CIRCUIT-BREAKERS accepted for slotted angles. All metal exposed
(MCBs) during fabrication shall be given a coat of zinc-rich
paint, brushed on, and finished matching the
2.8.1 MCBs shall comply with BS EN 60898 Manufacturers' finish.
and clause 2.1. They shall have the voltage and
current ratings and the category of duty, and be of 2.11.3 Frameworks mounted outside a building
the type, as indicated. or at other locations as indicated shall be hot-dip
galvanised to BS EN ISO 1461 or sheradize coated
to BS 4921. Metal exposed during fabrication shall
2.9 RESIDUAL CURRENT-OPERATED be cleaned with a wire brush and given a coat of
CIRCUIT-BREAKERS (RCBO) zinc-rich paint, brushed on.

2.9.1 RCBO's shall comply with BS EN 61008 2.11.4 Bolts, nuts, washers and screws shall be
(RCCB's) or BS EN 61009 (RCBO's) as non-corrosive and compatible with the environment
appropriate. The rated voltage, rated current, rated in which they are installed.
tripping current and rated breaking capacity shall be
as indicated.
2.12 ERECTION
2.9.2 Where indicated RCCB/RCBO's shall
have electronically amplified sensors. They shall be 2.12.1 Equipment, including associated
of the instantaneous, inverse definite minimum time accessories, shall be fixed independently of the
(IDMT) or fixed time delay type as indicated. wiring system. All fixing bolts, nuts, washers and
screws shall be non-corrosive and suitable for the
environment in which they are installed.
2.10 CONTACTORS
2.12.2 Equipment shall be located so that a clear
2.10.1 Contactors shall comply with BS EN working space for operation, inspection and
60947-4-1 and clause 2.1. They shall be air-break maintenance is provided. Minimum dimensions
type and have the voltage and current ratings, type shall be in accordance with the recommendations
of duty, utilisation category and electrical endurance contained in Defence Works Functional Standard
as indicated. Design and Maintenance Guide 08: Space
requirements for plant access, operation and
2.10.2 Contactors shall be electromagnetic, maintenance. In the case of cupboards which are too
suitable for the control arrangement as indicated. shallow to meet the requirement with the doors
Operating coils shall be suitable for alternating closed, equipment shall be located in the elevation
current (ac) unless otherwise indicated, and shall be area of the clear door opening.
protected by cartridge fuses. Latch-in contactors
shall be provided only where indicated. 2.12.3 Single items of equipment shall be
mounted 1450mm above finished floor level to the
2.10.3 Enclosures shall comply with clause 2.2. centre of the equipment, unless otherwise indicated.
Inbuilt isolating switches complying with clause 2.5 Groups of equipment, other than floor standing,
and selector/test switches shall be fitted, as factory-built assemblies, shall be arranged so that no
indicated. part of the equipment requiring access for operation
or maintenance shall be less than 500mm or more
than 2000mm above finished floor level, unless
2.11 FRAMEWORK otherwise indicated.

2.11.1 Frameworks for supporting electrical 2.12.4 The suitability of equipment to fit into the
equipment shall be constructed from mild steel plate available space shall be checked before it is ordered.
and strip, cold and hot rolled steel sections or slotted Where the requirements of clauses 2.12.2 or 2.12.3
angles, complying with BS EN 10162, 10111, BS

Edition 1-2004 5
Specification 34 Section Two - Power Distribution Equipment

are unable to be met, the Project Manager shall be shall be fixed by non-corrosive materials appropriate
consulted. to the intended application and location.

2.13.3 Characters for labels fixed on the means

of isolation at the origin of each installation shall be
2.13 MARKING AND NOTICES at least 10mm high and 1.5mm thick. On all other
labels characters shall be at least 4mm high and
2.13.1 All diagrams, charts, tables and the 0.5mm thick.
wording for labels and notices shall be submitted for
the approval of the Project Manager before they are 2.13.4 Where there are two or more incoming
installed. supplies this shall be clearly indicated at each point
of isolation. Labels on single-phase equipment
2.13.2 Identification labels shall be fixed to the supplied from a three-phase supply shall indicate the
outside of equipment enclosures. Label format and phase to which it is connected.
materials shall be appropriate to the installation and

6 Edition 1-200 4
Specification 34

Section Three - Power Distribution Cables

3.1 CABLES 3.2 JOINTING AND TERMINATING

CABLES
3.1.1 The type, size and conductor material of
power cables shall be as indicated.
3.2.1 Joints and terminations shall comply with
3.1.2 Paper-insulated cables up to, and clauses 3.2.2 to 3.2.12 inclusive, and with clauses
including, 1 lkV shall comply with BS 6480; they 3.3 to 3.9 inclusive as appropriate to the type of
shall be mass-impregnated, non-draining, belted cable. All joint and termination equipment shall be
type. Sheaths shall be of lead for armoured cables used to the Manufacturer's recommendations. The
and lead alloy for unarmoured cables. Project Manager shall be consulted where it is
proposed to install joints that are not indicated.
3.1.3 Paper-insulated aluminium sheath cables
up to, and including, 1 lkV shall comply with BS 3.2.2 The Project Manager shall be given
6480 as far as it is applicable. evidence that the joint or termination Manufacturer
has stated that the materials to be employed are
3.1.4 Combined neutral/earth (CNE) cables up suitable for the type of cable to be jointed or
to and including, lkV shall comply with Electricity terminated.
Association Technical Standard 09-9 for Waveconal
cable. They shall be used in TN-C-S systems only. 3.2.3 A cable shall not be cut until the jointing
or terminating commences and the work shall
3.1.5 Thermosetting (XLPE or EPR) insulated proceed continuously until it is completed. All
cables above 6.6kV and up to, and including, 33kV necessary precautions shall be taken to prevent
shall comply with IEC Standard 60 502 or BS 6622. damage and ingress of moisture and impurities.
Cable ends shall be free from moisture before
3.1.6 Thermosetting (XLPE) insulated cables jointing commences and a sample of paper from
up to, and including, 3.3kV shall comply with BS paper-insulated cables shall be tested for moisture.
5467, BS 7889 or BS 6724 as appropriate. Where circumstances prevent completion the cable
ends shall be sealed. This shall be by plumbing of
3.1.7 Thermoplastic (PVC) insulated cable up lead sheathed cables and by hermetically sealing
to, and including, 3.3kV, and armoured with wire or aluminium sheathed cables. For polymeric cables
aluminium strip, shall comply with BS 6346. with polymeric oversheaths appropriate heatshrink
or cold applied end caps shall be used.
3.1.8 Cables complying with Sections 8 and 10
may also be indicated for power distribution. 3.2.4 The Contractor shall employ staff who are
fully qualified and competent for the types of joints
3.1.9 ' Reduced neutral conductors shall not be and terminations to be made. Jointers employed for
used unless indicated. both LV and HV work must produce evidence of
training by the Manufacturer or an appropriate
3.1.10 An oversheath or serving, of the training authority in the completion of LV or HV
Manufacturer's standard colour for LV cables and joints and terminations as appropriate.
red for HV cables, shall be provided unless
otherwise indicated. 3.2.5 Core identification shall be matched at
each joint without twisting or crossing of the cores.
3.1.11 Installation of cables shall comply with Where numbered cores are jointed to coloured
Section 6. cores, the system adopted shall be consistent
throughout all cable runs and, on sites with existing
installations, consistent with the system already in
use. The location of the joint shall be recorded and
included in the handover documentation.

Edition 1-2004 7
Specification 34 Section Three - Power Distribution Cables

3.2.6 At the last joint in an HV run or in an connector for use with their product.
appropriately sized end box where phasing-out is to
be done, the joint or final connection shall not be 3.3.2 Cable soldering sockets shall be of correct
made until the Project Manager or his competent size for the conductor without excessive clearance.
representative has witnessed, and approved, the
phasing-out. 3.3.3 Compression connectors and associated
dies for the compression tool shall be the correct
3.2.7 Joints selected for use with armoured type and size. The tool shall be so designed that the
cables shall not reduce the fault current withstand correct compression must be applied before it can be
capacity nor increase the impedance of the circuit released.
protective conductor (CPC) and shall be of a type
approved by the Project Manager.
3.4 SLEEVES, TAPES AND SEALING
3.2.8 Armouring and metal sheaths shall be COMPOUNDS
connected by a bonding conductor directly to the
external earthing terminal of the equipment at all 3.4.1 Sleeves shall be of the shrink type,
terminations. The cross sectional area of bonding applied to the Manufacturers' recommendations.
conductors for LV cables shall be calculated or sized They shall provide sufficient thickness of insulation
in accordance with Table 54G of BS 7671: and HV to suit the particular application.
cables it shall be to BS 7197. Metal sheaths of
single core cables shall be bonded and earthed at one 3.4.2 Insulating tapes used in joints and
point only, unless indicated otherwise, and insulated terminations shall be compatible with, and have a
glands shall be used at the open-circuit end or ends. temperature rating and insulating property not less
than, the cable insulation. They shall comply with
3.2.9 Cable tails at terminations shall be formed BS 3924, but crepe paper tapes may be used for
by separating and bringing out the cores. Each tail jointing paper-insulated cables.
shall be long enough to connect to the terminals of
the equipment. 3.4.3 Impregnated cotton tapes shall be double
selvedge.
3.2.10 At the terminations of single core cables,
gland plates shall comply with clause 2.2.5. For 3.4.4 All tapes shall be stored in sealed
three phase circuits the phase conductors shall be containers until required.
arranged, where practical, in trefoil formation where
they pass through enclosures of equipment. 3.4.5 Resin fillings should, as far as is
reasonably practicable, be safe and without risk to
3.2.11 Core identification at LV terminations health. Each pack shall include COSHH
shall be by coloured or numbered plastic stretch or Regulations warnings about any hazards in its use,
shrink ferrules on the cores. For HV and LV eg. dermatitic or toxic properties, with details of the
terminations coloured or numbered discs shall be precautions that the user must take to minimise
provided on the outside of sealing boxes to indicate these.
the disposition of the phases and neutral conductors
inside. Insulating tape shall not be used for marking 3.4.6 Hot-pouring sealing compound shall be
cables inside joints or terminations. hard setting. Selection of the compound shall take
account of the ambient temperature of the
3.2.12 Continuity of spare cores shall be installation as well as the characteristics of the joint.
maintained at joints, and at terminations the cores Voids shall not be allowed in the compound.
shall be connected to earth at the supply end and in a
spare terminal at the load end.
3.5 JOINTING PAPER-INSULATED CABLES
3.3 CONNECTING AND TERMINATING 3.5.1 Joints shall comply with clauses 3.2, 3.3,
CONDUCTORS 3.4 and the following.
3.3.1 All connections and terminations shall 3.5.2 For lead sheath cables, joints shall be
normally be by means of compression fittings. made within an assembly comprising plumbed lead
Solder may be used only for connecting or or copper sleeves enclosed in casting moulds for
terminating paper-insulated cables. Mechanical cold pouring resins.
connectors may only be used where the
Manufacturer of the joint or termination has 3.5.3 For HV joints above 3.3kV, purpose-made
confirmed, in writing, the suitability of the chosen paper tube or crepe paper tape insulation is preferred
8 Edition 1-200 4
Specification 34 Section Three - Power Distribution Cables

with impregnated paper separators used with three- Manager. Fixing of pole-mounted boxes shall not
phase cables. Where these are not used, and for require any cutting of the pole.
joints up to and including 3.3kV, the radial thickness
of insulation over connectors shall be twice the
radial thickness of the cable core insulation. The 3.7 JOINTING AND TERMINATING
radial thickness of the belt insulation shall be equal THERMOSETTING AND THERMOPLASTIC
to the radial thickness of the cable core insulation. (PVC) INSULATED CABLES

3.5.4 The outer protection boxes for lead 3.7.1 Joints and terminations for Thermosetting
sheathed cables shall be cast-iron, split type. The (XLPE/EPR) and Thermoplastic (PVC) insulated
minimum thickness of compound between the inner cables shall comply with clauses 3.2, 3.3 and 3.4,
joint sleeves and the box shall be 12mm. Mould the appropriate Part of BS 4579, BS 7888 or BS
boxes for cast resin joints need not have additional 6910 and the following.
outer protection.
3.7.2 Joints shall be of the cast resin or shrink
3.5.5 For screened cable, continuity of type or combination of cast resin and shrink
screening shall be maintained across the joint. material.

3.7.3 Armour Termination shall be by means of

3.6 TERMINATING PAPER-INSULATED mechanical cable glands complying with BS 6121.
CABLES For armoured cables the glands shall have an earth
bond attachment. For cables with conductors larger
3.6.1 Terminations shall comply with clauses than 35mm the earth termination shall be integral
3.2, 3.3, 3.4 and the following. with the body of the gland. Glands used with
aluminium armoured cables shall be of aluminium,
3.6.2 A barrier against the ingress of moisture but for all other situations they shall be of brass,
into the cable cores shall be formed below unless otherwise indicated.
compound or shrink sleeve level. For copper
conductors up to and including 70mm, the cores 3.7.4 Shrink type or pre-moulded products may
shall be sweated solid, and for the larger sizes and be used where an HV cable termination is within an
for aluminium conductors a ferrule shall be sweated equipment enclosure, unless otherwise indicated. At
onto each core. The tails shall be lapped with tape the entry to the enclosure the cable shall be
complying with clause 3.4, or covered with shrink supported by a mechanical cable gland complying
type sleeves. with clause 3.7.3. The cable shall be securely
supported within the enclosure.
3.6.3 Shrink type sleeves may be used where
the cable termination is within an equipment Note: - Manufactures' advice shall be sought when
enclosure, unless otherwise indicated. At the entry replacing a compound filled termination with a heat
to the enclosure the cable shall be supported by a shrink type termination to ensure compatibility
bolt-on wiping gland at which the armouring shall between the termination type and the enclosure.
terminate. The cable shall be securely supported
within the enclosure. 3.7.5 Shrink type or pre-moulded products may
be used where a termination is pole-mounted,
3.6.4 End dividing boxes shall be one of the subject to the approval of the Project Manager.
following types, as indicated: Additionally, HV cables shall be fitted with shrouds.

1. Compound filled, split type, cast-iron boxes

with filling holes sealed by screwed plugs or 3.8 JOINTING CNE CABLES
caps, and with brass wiping glands and armour
clamps. Top plates shall be tapped, or 3.8.1 Jointing shall comply with the clauses of
provided with porcelain bushings or insulators this Section relevant to the type of cable. The
as required. Tapped top outlets shall have a protective conductor shall not be broken under any
minimum of 10mm of thread. circumstances when making a service tee-joint.

2. Cast iron or fabricated steel cable boxes fitted

to switchgear or transformers. 3.9 JOINTING DISSIMILAR CABLES

3.6.5 Pole mounted boxes for LV cables shall 3.9.1 Dissimilar cables shall be jointed only
be cast-iron of the tier type, but shrink type sleeves where indicated or with the approval of the Project
may be used subject to the approval of the Project Manager.
Edition 1-2004 9
Specification 34 Section Three - Power Distribution Cables

3.9.2 Jointing shall comply with clauses 3.2, 3.10 STOP ENDS
3.3, 3.4 and shall be suitable for the two types of
cable concerned. 3.10.1 The term "STOP END" means the
provision of a permanent seal in which all cores are
insulated and protected so that the cable can be
energised safely.

10 Edition 1-200 4
Specification 34

Section Four - Alarm, Control, Communication and

Monitoring Cables

4.1 CABLES 4.3.3 Joints in multi-pair cables with 20 or

fewer pairs, including tee-joints having a branch
4.1.1 The type and size of cables shall be as cable of not more than four cores, shall be made in
indicated. Section 4 specifies those, which will be single ended bell-type boxes with expanding plug
most commonly used. assemblies. The complete cable, including the
armouring and outer sheath, shall be clamped in a
4.1.2 Thermosetting and Thermoplastic neoprene expander plug.
insulated and sheathed cables, with or without
screening and armouring, shall comply with BS 4.3.4 Joints in cables having more than 20
3573. pairs, including tee-joints having a branch cable of
not more than four cores, shall be made as indicated.
4.1.3 Cables shall be installed in accordance Approved sleeve type boxes complying with the
with this Section, Section 6, and Sections 3, 8, 9 or cable Manufacturer's recommendations shall be
10, as appropriate. used.

4.3.5 Link disconnecting units located above

4.2 JOINTS AND TERMINATIONS ground shall be used where tee-joints having a
branch cable of more than four cores are to be made.
4.2.1 Joints and terminations shall comply with
clause 4.2.2, and appropriate parts of Sections 3 and
10. For coaxial cables and other special cables, 4.4 TERMINATING THERMOPLASTIC
joints and terminations shall comply with the (POLYETHYLENE) INSULATED CABLES
Manufacturer's requirements.
4.4.1 Terminations shall comply with clause 4.2
4.2.2 Joints shall be located above ground and the following.
unless otherwise indicated. Joint boxes shall be
supported securely on short posts or other approved 4.4.2 Cables shall be terminated at link
structures. Where joints are buried, the joint box disconnecting units (LDU), which shall be supplied
shall be positioned a short distance from, and at complete with terminal strips and compression
right angles to, the line of the route and at the same glands.
depth as the cable.
4.4.3 The armouring of all cables entering the
LDU shall be bonded together, unless otherwise
4.3 JOINTING THERMOSETTING indicated. The conductivity of the bonding
POLYETHYLENE-INSULATED CABLES conductor shall be not less than the conductivity of
the armouring of the largest cable.
4.3.1 Joints shall comply with clause 4.2 and
the following.
4.5 JOINTING THERMOSETTING
4.3.2 Joints in two-core cables shall be made in (POLYETHYLENE) INSULATED CABLES TO
adaptable boxes complying with clause 8.3. Cables PAPER-INSULATED CABLES
shall be terminated at the boxes with compression
glands and armour clamping cones. Joints in 4.5.1 Joints shall comply with clauses 4.2 and
conductors shall be made using insulated terminal shall be made using single ended bell-type boxes
blocks complying with the requirements of clause with expanding plug assemblies.
12.19. Boxes shall be filled with an inert,
permanently plastic compound having a high 4.5.2 The finished joints shall be filled with an
insulation value, and shall be completely wrapped in inert, permanently plastic compound having a high
Thermoplastic (PVC) self-adhesive tape or similar. insulation value.

Edition 1-2004 11
Specification 34 Section Four- Alarm, Control, Communication and Monitoring Cables

4.6 SEGREGATION
4.7 MARKING
4.6.1 Segregation of cables from those of other
systems and from equipment, pipework and 4.7.1 Marking of cables and the termination of
ductwork shall comply with clause 6.2 and with any conductors shall comply with clause 6.11, 8.1.5,
additional requirements that are othewise indicated. 9.1.2 and 10.6.9 as appropriate, to the type of cable.
Any requirements that are indicated for segregating
circuits of particular systems shall be observed. 4.7.2 A label indicating the system concerned
shall identify all joint boxes. Labels shall be in
4.6.2 Band 2 cables shall not be installed in the accordance with clause 2.13.
same conduits, trunking compartments or cable
ducting compartments as Band 1 cables, unless 4.7.3 A diagram showing the allocation of
otherwise indicated, and any requirements that are terminals for each incoming cable shall be
indicated for segregating circuits of particular permanently fixed inside each joint box cover. The
systems shall be observed. diagram shall be afforded protection suitable for the
environment in which it is located.

12 Edition 1-200 4
Section Five - Cable Supports

5.1 SELECTION OF CABLE SUPPORTS complying with BS EN 10130, 10131 or 10149 as

appropriate. Trays and supports shall be selected to
5.1.1 The type and sizes of cable support provide adequate support without sagging more than
systems shall be selected by the Contractor to suit 1/360 of the support span, or as indicated.
the circumstances of the installation, unless
otherwise indicated. They shall also comply with 5.3.3 Bends, tees, risers, reducers and four-way
clauses 5.2 to 5.8 inclusive, and the following crosspieces shall be factory made wherever possible,
preferences shall be taken into account: and shall be of the same construction, material,
thickness and finish as the cable tray. All tees and
• for horizontal runs - cable tray or cable crosspieces shall have a 45° gusset on each side
rack from the point of intersection.

• for vertical runs - cable cleats or cable 5.3.4 Cable trays shall be cut along a line of
tray or cable rack. unperforated material. Holes cut in cable trays for
the passage of cables shall be fitted with grommets,
Where marshalling of cables occurs (eg. at bushes or other lining. Cutting of cable trays shall
switchboards) - cable racks. be kept to a minimum.

5.1.2 The selection, sizing and installation of 5.3.5 Each length of a cable tray shall be
cable supports shall take account of the requirements securely bolted to an adjacent length with factory
of Section 6. made couplings of adequate dimensions to prevent
sagging or twisting in accordance with the
Manufacturer's recommendations. Where required,
5.2 PROTECTIVE FINISHES FOR FERROUS bolts and nuts shall be appropriately dimensioned
MATERIALS mushroom-head steel roofing type complying with
BS 1494. Ends of coupling bolts shall not come into
5.2.1 All ferrous metal for cable tray, cable contact with the cables. No welding shall be used in
racks, cable ladder, cable hangers and their fixings the joining of cable trays.
and suspensions shall have a galvanised finish.
5.3.6 Where cables are laid on the cable tray
5.2.2 Galvanised finishes shall be hot dipped to they shall be secured by ties, each tie securing the
BS EN ISO 1461, except that support steelwork in cables of only one circuit. The ties shall be of a
dry indoor unpolluted areas shall be galvanised to proprietary type low in halogen, self extinguishing
Z275 of BS EN 10147. and ultra-violet resistant. The use of wire or similar
material is not permitted. Ties shall be used at less
5.2.3 In offshore, coastal and polluted areas than 600mm intervals along each cable, and within
where ferrous materials are used, consideration shall 100mm of each bend or set.
be given to the use of stainless steel or silicon steel
with 1200 g/m2 coating to BS EN ISO 1461. 5.3.7 Cables shall be supported by cable cleats
where cable trays are vertical. Mineral-insulated
cables on vertical trays shall be supported by saddles
5.3 CABLE TRAY or clips.

5.3.1 Cable tray shall be metal, plastic or GRP, 5.3.8 Cable trays shall be fixed at regular
as indicated. Metal cable tray shall comply with intervals in accordance with Manufacturer's
clauses 5.2 and 5.3.2 to 5.3.8. Steel mesh basket recommendations but not exceeding 1200mm and at
trays may be used only for data, communications, 225mm from bends and intersections. A minimum
alarm and similar wiring systems, unless otherwise clear space of 25mm shall be left behind all cable
indicated. trays.

5.3.2 Cable trays shall be perforated. Metal 5.3.9 Cable trays shall be installed with a 20mm
cable trays shall be formed from carbon steel plate gap at building or structural expansion joints. Cable
Edition 1 - 2004 13
Specification 34 Section Five - Cable Supports

tray supports shall be installed within 150mm on 5.6 CABLE HANGERS

either side of the joint.
5.6.1 Cable hangers shall be used only where
indicated. They shall be made from mild steel flat
5.4 CABLE CLEATS bar complying with clause 5.2.

5.4.1 Cable cleats shall be made from materials

that are resistant to corrosion without the need for 5.7 SUSPENSION AND FIXINGS
treatment or special finish. Plastic materials shall be
non-brittle down to -20°C. Non-metallic cleats used 5.7.1 Proprietary suspension systems
for low smoke fume (LSF) cables shall be of LSF comprising channel sections with return lips and
material. compatible fixing accessories or slotted angles
complying with BS 6946 shall be used. Fixings may
5.4.2 Cable cleats shall be of a size such that be fabricated from mild steel flat bar where
they can be tightened down to grip the cables necessary. Metal arc welding shall comply with BS
without exerting undue pressure or strain on them. EN 1011.
For vertical cables two-bolt cable cleats shall be
used which shall grip the cables firmly enough to 5.7.2 Fixing to the building fabric shall comply
prevent them slipping. with Table 5A, unless otherwise indicated.

5.4.3 The spacing of cable cleats shall comply 5.7.3 No shot firing shall be used and no
with the IEE Guidance Notes to BS 7671. Cleats drilling or welding of structural steelwork shall be
shall be located immediately on each side of bends done without the approval of the Project Manager.
in the cable.
5.7.4 Suspensions and fixings shall comply with
5.4.4 Single core cables shall be cleated with clause 5.2.
trefoil cleats, where appropriate.
5.7.5 Bolts, nuts, washers and screws shall be
non-corrosive and compatible with the environment
5..5 CABLE RACKS AND CABLE LADDERS in which they are installed.

5.5.1 Cable racks shall comply with clause 5.2

and shall be constructed from proprietary systems 5.8 BONDING
using channel sections with return lips and
compatible fixing accessories. 5.8.1 Metallic cable trays, racks and ladders
shall be electrically and mechanically continuous
5.5.2 Ladder rack shall be factory made from throughout and bonded to the earth system.
steel complying with clause 5.2.
5.8.2 Supplementary bonding shall be installed
5.5.3 Racks and supports shall be selected to wherever necessary, between component parts of
provide adequate support without racks sagging cable trays, racks or ladders where the method of
more than 1/360 of the support span, or as indicated. mechanical connection does not provide permanent
and reliable metal-to-metal joints of negligible
5.5.4 Cable racks and ladders shall be installed impedance. An earth bonding strip having a
with a 20mm gap at building or structural expansion minimum cross section of 6mm2 shall be installed
joints. Supports shall be installed within 150mm on across the gap at building or structural expansion
either side of the joint. joints.

5.5.5 Cables shall be fixed to racks and ladders

by cable cleats.

14 Edition 1 - 2004
TABLE 5A FIXING FOR CABLE SUPPORTS

Building Fabric Type of Fixing

Structural steelwork Purpose made clamps, the type to be approved by the Project Manager.

Non-structural steelwork As for structural steelwork, or bolts, washers and nuts

Concrete, brick or building blocks Expanding anchors, or screws and plugs, to be approved by the Project
Manager.

Timber Coach Bolts

Edition 1 - 2004 15
Specification 34

16 Edition 1 - 2004
Specification 34

Section Six - Cable Installation

6.1 ROUTES ground. Fixing direct to the building fabric by cable

cleats may be adopted for single runs subject to the
6.1.1 Unless the routes of cables are indicated approval of the Project Manager, and where
on the drawings they shall be determined by the indicated.
Contractor and approved by the Project Manager
before work is started. 6.3.2 Where cables are not continuously
supported, the supports shall be spaced to the cable
6.1.2 Cables installed on the surface shall be Manufacturer's recommendations.
parallel with the lines of the building construction
and properly aligned. 6.3.3 Cables shall be supported within 300mm
of their termination at equipment. The weight of a
6.1.3 Cables buried below ground shall, as far cable shall not be carried by a terminal box or gland.
as practicable, follow the features of the site such as The distance may be increased to suit the
roadways and building lines. Ducts at road and rail requirements of clause 13.11.
crossings shall normally be at right angles to the line
of the road. 6.3.4 Where cables cross expansion and
settlement joints in the building structure they shall
be fixed 300mm each side of the joint and sufficient
6.2 SEGREGATION slack left between to allow for movement. Where
the cables are buried in the building fabric, suitable
6.2.1 A minimum clearance in accordance with provision shall be made to allow for movement of
Table 6A shall be allowed from any equipment, the structure. The Contractor shall submit his
pipework or ductwork. The distance shall be proposals for the approval of the Project Manager.
measured from the external surface of any lagging.
In the event of difficulty in achieving these
requirements the Project Manager shall be 6.4 TRENCHING
consulted.
6.4.1 No work shall commence until the
6.2.2 Spacing between cables shall comply with Contractor has taken all reasonable steps to ensure
Table 6A and be arranged so that the grouping factor that the area is free of all cables, drains and other
used in the cable calculations shall not be affected. services, or that the location has been determined of
In the event of difficulty in achieving these those services known to exist. Health and Safety
requirements the Project Manager shall be Executive publication HS(G) 47 gives guidance for
consulted. avoiding underground services.

6.2.3 Where indicated, space shall be allowed 6.4.2 Unless otherwise indicated, excavations
along cable routes for future additions, and cable within 600mm of existing services shall be by hand
supports shall be of adequate size for the ultimate digging. All services uncovered, whether expected
load. or not, shall be reported immediately to the Project
Manager, and they shall be supported by slings or
6.2.4 Adequate space shall be left between other suitable means and protected. Any damage to
cable runs and the building fabric and other services services, however minor, shall be reported
to allow for the future removal or installation of immediately to the Project Manager. No repairs or
cables. replacement shall be done unless the Project
Manager gives approval.
6.3 SUPPORTS AND FIXINGS
6.4.3 When cable trenches are opened, all
6.3.1 Cables shall be adequately supported, by necessary safety precautions shall be taken to
one of the methods specified in Section 5, prevent accidents and damage occurring. Cables
throughout their length except where they run shall be laid expediently with regard to project
through cable ducts or are buried direct in the requirements. The Project Manager's approval shall
be obtained before a trench is backfilled. Ideally

Edition 1-2004 17
Specification 34 Section Six - Cable Installation

backfilling shall be commenced within 24 hours of 300mm below the finished surface level except
cable laying and the work completed speedily. where the depth of roadway or paved area base
exceeds 300mm in which case the tape shall be laid
6.4.4 Cables shall be buried at a sufficient depth immediately below the base.
to avoid being damaged by any disturbance of the
ground reasonably likely to occur. Trenches shall be 6.5.2 Warning tapes shall be of polythene not
excavated to such depth but not less than specified less than 150mm wide and 0. lmm thick. They shall
in Table 6B. be yellow in colour and bear the continuously
repeated legend "CAUTION ELECTRIC CABLE
6.4.5 Turf and topsoil shall be removed BELOW", or similar, in black letters not less than
carefully and preserved for reinstatement in their 30mm high.
original positions. Spoil from the trench intended for
re use as reinstatement material shall be removed 6.5.3 Interlocking cable warning covers shall be
from the lip of the trench by at least 150 mm. provided for HV cables and for mineral-insulated
cables. For other cables they shall be provided only
6.4.6 Excavations shall be carried out in where indicated. They shall be of proprietary
accordance with BS 6031, BS 8000 Part 1 and shall manufacture and shall be laid directly on the tamped
comply with the Construction (Working Places) sand that covers the cables.
Regulations, 1966 and all other relevant statutory
requirements. Excavations shall be kept free of
water and protected against damage or collapse. 6.6 DUCTS
The safety of persons and the protection of
structures, buildings, roads, sewers and services 6.6.1 Cables shall be installed in cable ducts
from damage shall be ensured. All necessary where they pass under, or within, 5m of railway
sheeting, timbering, strutting and shoring shall be tracks, where they pass under roadways or other
supplied, erected and subsequently removed. areas with vehicular access, where they are
supported on bridges, where they enter buildings,
6.4.7 Before cables are laid, the bottom of the and additionally where indicated.
trench shall be graded evenly, cleared of loose
stones and then covered for the full width of the 6.6.2 Cables shall be protected by steel tubes on
trench with a 75mm layer of compacted sieved sand. bridges. All other cable ducts shall be selected by
Where the level of the trench bottom has to change the Contractor from the alternatives listed in clauses
the slope shall not be greater than 1 in 12. 6.6.4 to 6.6.6 to suit the circumstances of the
installation, unless otherwise indicated.
6.4.8 After cables have been laid a further layer
of sieved sand shall be added over the full width of 6.6.3 Ducts shall be of a size suitable for the
the trench, and tamped to provide finally not less cables to be drawn-in and withdrawn without
than 50mm cover over the cables. damage. The minimum size of bore shall be 100mm.
The bore shall be smooth and entirely free from
6.4.9 Trenches shall be backfilled in layers and rough spots, sharp edges, imperfections and
each layer shall be rammed. The first two layers protuberances.
shall be 100mm deep and rammed by hand; the
remaining layers shall be not less than 200mm deep 6.6.4 Cable ducts of vitrified clay shall comply
and power ramming may be used. Warning tapes with BS 65 and shall be extra strength class. They
and covers shall be included as specified in clause shall be joined with plastic flexible sleeves to
6.5. Where applicable, topsoil and turf shall be provide self-alignment of the bore.
replaced and the final level shall be level with, or
not more than, 25mm above, the adjacent ground 6.6.5 Thermoplastic (PVC) ducts shall be
level. A higher degree of consolidation is required unplasticized Thermoplastic (PVC) pipe complying
for excavations within shoulders and over-runs and either with BS 4660 or BS 5481 as appropriate, or
adjacent to paved areas used by aircraft. At these with BS 3506 classes B, C, D or E. They shall have
locations the final layer of reinstatement shall be rubber sealing rings complying with BS EN 681.
compacted by power ramming until maximum Thermoplastic (PVC) ducts shall not be used where
possible compaction is achieved. the depth of cover exceeds lm.

6.6.6 Steel tubes shall comply with BS 1387

6.5 WARNING TAPES AND COVERS and shall have screwed socket joints and end bushes.
Tubes shall be protected against corrosion with a
6.5.1 A warning tape shall be placed above each coat of bitumastic paint before they are installed.
cable that is laid direct in the ground and above each Tubes of 100mm bore shall be of light thickness;
cable duct. The tape shall be laid at a depth of above this size they shall be medium thickness.
18 Edition 1 - 2004
Specification 34 Section Six - Cable Installation

6.7 LAYING OF DUCTS 550N and shall be at least 4m longer than the duct
run.
6.7.1 Unless otherwise indicated, cable ducts
shall be laid at depths which comply with the 6.7.10 Immediately after laying, and before
requirements of Table 6B. backfilling the trench, the ends of the cable ducts
shall be sealed temporarily with proprietary plugs.
6.7.2 The bottom of trenches shall be rammed Draw-lines shall be secured outside the plugs.
to provide a flat firm bedding. Where rock is
present a layer of loose soil shall be spread over the 6.7.11 Backfilling shall be in accordance with
bottom and also rammed. In water-logged or clause 6.4.9. Where a cable duct is not used
unstable soil a 75mm thickness of grade 10 concrete, immediately, temporary marker posts shall be
as defined in BS 8110, with 20mm aggregate shall installed to locate the ends of the duct and shall be
be laid as a foundation and soil placed around and retained in position until cables are drawn in.
above to a depth of 75mm above the top of the duct. Markers shall be white painted wooden posts 75mm
x 75mm, standing not less than 600mm out of the
6.7.3 Where cable ducts pass under, or within, ground.
5m of railway tracks or under roadways, the bottom
of trenches shall be rammed and the ducts laid on, 6.7.12 Ducts shall be cleared with a mandrel
and surrounded by concrete, providing a minimum 150mm long and having a diameter 12mm less than
cover of 150mm all around. The concrete shall be the bore diameter immediately before cables are
grade 20, as defined in BS 8110, with 20mm drawn-in. The mandrel shall be followed by a
aggregate. At each joint in the ducts, flexibility circular wire brush with a diameter 12mm more than
shall be maintained by forming a joint in the the bore diameter.
concrete by a 25mm thick compressible foam filler.

6.7.4 Cable ducts shall extend not less than lm 6.8 HANDLING OF CABLES
beyond the limit of roadways and paved areas. They
shall be at least 150mm away from gas and water 6.8.1 Installation of cables shall be carried out
pipes, drains, sewers and electrical plant. Where only when the ambient temperature is above 0°C
services cross, the clearance shall be not less than unless a written statement from the Cable
50mm. If difficulty arises in achieving these Manufacturer confirms that no damage to the cable
minimum clearances the Project Manager shall be will result, and the approval of the Project Manager
consulted. is given. The temperature of the cable shall have
been above 0°C, or above the minimum temperature
6.7.5 Deflection from a straight line and recommended by the Manufacturer, for at least 24
variation in depth shall not exceed 1 in 30 hours immediately prior to installation. Any special
horizontally nor 1 in 60 vertically and the cable duct measures to achieve this shall be subject to approval
shall pass the alignment tests. by the Project Manager.

6.7.6 Draw-pits shall be constructed at each 6.8.2 Cables shall be handled with care and
change of direction and, for straight runs, at intervals every effort made to avoid damage to the cables, to
not exceeding 25m unless otherwise indicated. other services and to the building fabric.
Draw-pits shall be of adequate size to enable cables Recommendations or instructions available from the
to be drawn-in without damage or undue stress due cable Manufacturer concerning the installation of
to bending. The construction of draw-pits and their cables shall be taken into account. Any damage
covers shall be as indicated. shall be reported immediately to the Project
Manager.
6.7.7 Concrete shall comply with BS 8110 and
shall be of a class suitable for the sulphate content of 6.8.3 Cable drums shall be unloaded carefully
the soil in accordance with Table 6.1 of the Code of by means of either a crane or ramp and impact with
Practice. the ground shall be avoided. They shall be
supported on axles or axle stands while the cable is
6.7.8 Alignment shall be proved by drawing a being pulled. Twisting and abrasion of the cable
mandrel through each duct. The diameter of serving or oversheath shall be avoided.
mandrel shall be 7mm less than the bore diameter.
Mandrels shall be of wood, 250mm long. 6.8.4 Cables shall be pulled over cable rollers
adequately spaced to prevent the cable being
6.7.9 While cable ducts are being laid nylon, dragged over ground or other surface. Cable
polypropylene or similar draw-lines shall be stockings shall be used for hauling cables pulled into
threaded through each length of duct. The draw- thrust borings or cable ducts, and for all cables
lines shall have a breaking strength of not less than exceeding 10m length. Precautions shall be taken to

Edition 1 - 2004 19
Specification 34 Section Six - Cable Installation

ensure that strain is taken on the cable cores as well requirements of BS 476 Parts 20 and 22 for
as the sheath and excessive strain shall be avoided. insulation, stability and integrity for the period of
Under no circumstances shall vehicles be used to time indicated. The method shall be submitted for
pull cables in, appropriate cable winches or hand the Project Manager's approval before work
pulling only shall be used. commences.

6.8.5 Cables laid in trenches shall cross other

cables only at junctions. Clearances between the 6.10 CABLE GUARDS
cables shall be maintained at crossovers. Cables
shall not be laid one above the other except where 6.10.1 Cable guards shall be fitted where cables
indicated. are mounted at low level on walls, poles, towers or
other locations as indicated.
6.8.6 Only one cable shall be pulled into each
duct except for the following, which may be 6.10.2 Cable guards shall be constructed from
bunched subject to the requirements of Table 6A and 1.6mm thick galvanised steel sheet complying with
a maximum space factor of 20%. clause 2.11 and formed into a casing with external
flanges for fixing to the fabric.
Single-core cables forming one circuit;
6.10.3 Guards shall extend to a height of 3.5m
Mineral-insulated cables; above ground or floor level for HV cables and 1.5m
for LV cables. In external locations the guards shall
Alarm, control, and monitoring cables; extend 300mm below finished ground level and they
shall be protected inside and out with bitumastic
Pilot cables associated with another power paint extending from the bottom up to 150mm above
cable in the duct. finished ground level.

Cables that are to be installed in the same

duct shall be bunched together and pulled in 6.11 MARKING OF CABLES
one operation. Additional cables shall not
be drawn-in subsequently. 6.11.1 Marker posts or slabs shall permanently
identify the location of buried cables. The wording
6.8.7 The ends of all cables shall be sealed on the markers shall be "HV CABLE" or "LV
during installation by an appropriate heatshrink or CABLE" as appropriate; in addition the word
cold applied end cap, unless jointing or termination "JOINT" shall be added where appropriate. Posts
is carried out immediately. The sealed ends of shall only be used where they do not cause
power cables shall be marked with the letter "A" or obstruction or danger.
"Z" to indicate the core sequence: "A" at the end
where the sequence is clockwise and "Z" where it is 6.11.2 Cable marker slabs shall be installed, as
anti-clockwise. required, flush with the finished ground level, on the
precise line of the cable.
6.8.8 At no time shall cables be bent to a radius
less than the Manufacturer's recommended 6.11.3 Cable markers shall be located at every
minimum. point where a cable enters a building, sub-station,
plinth or distribution pillar, at each joint, change of
direction, road and pathway crossing, and along the
6.9 SEALING DUCTS AND OPENINGS route of the cable at intervals not exceeding 45m.

6.9.1 The ends of all ducts and service conduits 6.11.4 Cables shall be colour coded in
(including spare ways) shall be sealed after cables accordance with BS 1710 except where cables are
have been installed. buried, located in switchrooms, in ducts and spaces
designated solely for electrical services, or have
6.9.2 Where ducts and service conduits enter orange oversheaths. Colour coding, where used,
buildings, proprietary seals shall be used to form a shall be conspicuous bands, not less than 100mm
barrier against gas, water, oil, fire and attack by long, located at least once within each separate
vermin. Spare ducts and service conduits shall be compartment through which the cables pass and at
similarly sealed with removable material. The intervals not exceeding 12m.
method of sealing shall be submitted for the Project
Manager's approval before work commences. 6.11.5 Trunking or ducting shall be permanently
and conspicuously identified. The method of
6.9.3 Fire barriers at fire-resistant structural identification shall be as indicated or approved by
elements, such as floors and walls, shall satisfy the the Project Manager
20 Edition 1 - 2004
Specification 34 Section Six - Cable Installation

6.11.6 Cables shall be permanently and 6.11.8 Every cable end shall be provided with a
conspicuously identified. The method of means of identification showing the designation,
identification shall be as indicated or approved by number and cross-sectional area of cores and rated
the Project Manager. voltage of the cable.

6.11.7 Cable identification shall be located 6.12 REDUNDANT CABLES

within 500mm of terminations and joints, at least
once within each separate compartment through 6.12.1 Where indicated, redundant cables shall
which the cables pass, at intervals not exceeding be removed or stop-ended in a manner complying
24m, and shall coincide with the colour bands, with clause 3.10 and clearly marked.
where used. Consideration shall also be given to
identifying cables at entry or exit points and where 6.12.2 Removed cables shall be disposed of in a
buried cables emerge from the ground. manner approved by the Project Manager.

Edition 1-2004 21
Specification 34 Section Six - Cable Installation

TABLE 6A MINIMUM SPACING OF CABLES

Equipment
Location Cable HV LV Telephone Co-axial Pipework
Ductwork
mm mm mm mm mm mm
Buried:
HV 50 300 300 300 300
LV 300 25 300 150 300
Telephone 300 150 50 50 200
Co-axial 300 150 150 150 200
Fibre Optic 300 150 50 50 200
In Air:
HV 50 300 300 300 300
LV 300 (see note 2) 150 150 150
Telephone 300 150 0 0 100
Co-axial 300 150 0 0 100
NOTES:
1. The minimum spacing apply unless otherwise indicated.
2. LV cables in air may be bunched subject to any requirements regarding segregation and installation methods set out in the BS 7671:
Requirements for Electrical Installations, Guidance Note No.1, and as stated in 6.2.
3. When cables are in steel pipes the minimum spacings need not be maintained, but a minimum space of 25mm shall be left between the
pipes.

TABLE 6B MINIMUM COVER FOR CABLES

TABLE 6B MINIMUM COVER FOR CABLES

Type of Location and Depth of Cover
cable

In open ground and under Under Under or In other

pavements roadways alongside situations
railways

mm mm mm mm

HV 800 1000
1800 As indicated

LV 600
Telephone 500 (light traffic)
Co-axial 800
Fibre Optic (heavy traffic)

22 Edition 1 - 2004
Specification 34

Section Seven - Overhead Lines

7.1 OVERHEAD LINES 7.2.3 The Contractor shall include, for the
supply and fixing of all insulators, brackets or
7.1.1 HV overhead lines shall comply with timber posts necessary for terminating service lines
Electricity Association Technical Standard 43-40. at buildings, unless otherwise indicated. Brackets
and fixings shall comply with Section 5.
7.1.2 LV overhead lines shall comply with the
latest issue of Electricity Association Technical
Standard 43-30. 7.3 CATENARY WIRE SUPPORTS

7.3.1 Short span overhead links between

7.2 CONNECTIONS TO BUILDINGS buildings shall be Thermoplastic (PVC) insulated
cables complying with BS 6004, with copper or
7.2.1 Service lines shall be Thermoplastic aluminium conductors as indicated. The cables shall
(PVC) insulated cables with copper or aluminium be supported by a catenary wire which shall be
conductors as indicated, complying with BS 6485, preferably integral with the cable.
type 8 or 16 as appropriate for the nominal voltage
of the system and BS 7884, BS 215 or BS EN 50183 7.3.2 Catenary supported cables shall be
as appropriate. installed in accordance with the BS 7671 and the
IEE Guidance Notes.
7.2.2 Cables from the service line termination
into the building shall be single core Thermoplastic 7.3.3 Details of the type of catenary system and
(PVC) insulated with a sheath, complying with BS fixing to be used shall be submitted to the Project
6004. Core identification colours shall extend Manager, whose written approval shall be obtained
throughout the length of the cables. before work proceeds.

Edition 1 - 2004 23
Specification 34

24 Edition 1-2004
Specification 34

Section Eight - Wiring System: Cables in Conduit,

Trunking and Ducting

8.1 CABLES 8.3.3 When located outside buildings, adaptable

conduit boxes and covers shall be as indicated.
8.1.1 The type and size of cables shall be as
indicated. Clauses 8.1.2 to 8.1.4 specify those 8.3.4 When conduit boxes are installed flush
which will be used most commonly. with the building fabric, overlapping covers shall be
fitted.
8.1.2 Thermoplastic (PVC) insulated sheathed
and non-sheathed cables shall comply with BS 6004. 8.3.5 Flexible steel conduit for general use
They shall have copper conductors unless otherwise inside buildings shall be Type A with protection
indicated. against corrosion equivalent to Class 2. For use in
plant rooms and other locations as indicated the
8.1.3 LSF cables shall comply with BS 7211 protection shall be Class 4. Adaptors shall be of the
and shall have copper conductors unless otherwise solid type.
indicated.
8.3.6 Prewired pliable conduit systems may
8.1.4 Thermosetting (Rubber) insulated non- only be used where indicated.
sheathed cables shall comply with BS 6007.

8.1.5 Core identification colours shall extend 8.4 NON-METALLIC CONDUIT

throughout the length of Thermoplastic (PVC)
insulated cables. Where appropriate the colours 8.4.1 Non-metallic conduit shall be rigid heavy
shall be as indicated. The additional identification duty Thermoplastic (PVC) unless otherwise
requirements of clause 8.12.6 shall also be met. indicated. Joints shall be made using solvent
approved by the conduit Manufacturer.
8.1.6 Cables shall be protected throughout their
length by trunking, ducting, conduit and equipment 8.4.2 Pliable conduits shall be heavy duty,
enclosures. Framework or partitions may only be reinforced, unless otherwise indicated. Pliable
used as protection with sheathed wiring systems. conduit shall not be used where the ambient
temperature may exceed 60°C or where mineral oils
or petrol are present.
8.2 CONDUIT
8.4.3 Flexible conduits shall be used for
8.2.1 Conduit, including flexible and pliable connections to moving or vibrating equipment.
conduits, shall be either steel or non-metallic as
indicated, and comply with the appropriate British
Standards. 8.5 TRUNKING AND DUCTING

8.5.1 Trunking and ducting shall be of steel or

8.3 STEEL CONDUIT AND FITTINGS insulating material as indicated, and shall comply
with BS 4678 and clauses 8.6 or 8.7 where
appropriate.
8.3.1 Steel conduits and fittings shall be
screwed classification unless otherwise indicated or 8.5.2 Trunking shall provide a minimum degree
approved by the Project Manager. of protection of IP41 when used inside buildings and
shall not normally be used in wet or outdoor areas.
8.3.2 The protection against corrosion of Trunking used outside buildings, or at other
conduits and conduit fittings for general use inside locations indicated, shall provide a minimum degree
buildings shall be Class 2. For use outside buildings, of protection of IP44.
in plant rooms, floor trenches, other locations as
indicated and in floor screeds, the protection shall be 8.5.3 Partitions shall be of the same material as
Class 4. the trunking or ducting. The gap between partitions
Edition 1 - 2004 25
Specification 34 Section Eight - Wiring System: Cables in Conduit, Trunking and Ducting

and trunking covers shall be a minimum to ensure maintained through the boxes.
that segregation of circuits is maintained.
8.7.3 Each service outlet box shall have outlet
8.5.4 Manufacturer's proprietary fittings shall units as indicated. The complete assembly shall
be used. Site fabricated fittings may only be used comply with the requirements of BS 6701.
with specific written approval of the Project
Manager and only where these are inadequate will 8.7.4 Lids of service outlet boxes and of floor
site fabricated fittings be accepted. Fittings trunking shall be of cast aluminium unless otherwise
fabricated on site shall be comparable in indicated. The lids shall be arranged to
construction with the rest of the trunking or ducting accommodate the floor finish, as indicated.
system.
8.8 ROUTES AND SEGREGATION
8.5.5 Ends of runs shall be fitted with
removable covers to permit future extension. 8.8.1 The routes of conduit, trunking and
ducting shall be as indicated. Where there is a
8.5.6 The size of trunking and ducting shall be discrepancy or omission, the route shall be
as indicated. determined by the Contractor and approved by the
Project Manager before work is started. This
8.5.7 Trunking with the cover on the side or requirement shall apply where the conduit, trunking
bottom shall be fitted with removable cable retaining or duct is concealed within the building fabric as
straps at intervals not exceeding lm. Cables shall be well as where they are on the surface.
supported at intervals not exceeding 3m where
trunking runs vertically. The method of support 8.8.2 Conduit, trunking and ducting shall be
shall allow for future easy removal of, or addition parallel with the lines of the building construction
to, the cables and shall be submitted for the approval and properly aligned, except where conduit is
of the Project Manager. permitted in floor screeds. Conduit buried in wall
finishes shall run vertically only, unless the Project
Manager gives approval to deviate from this
8.6 STEEL TRUNKING requirement.

8.6.1 Unless otherwise indicated, the protection 8.8.3 A minimum clearance of 150mm shall be
against corrosion for general use inside the buildings allowed from any equipment, pipework or ductwork;
shall be Class 2; for use outside buildings, in plant the distance being measured from the external
rooms, floor trenches and other locations as surface of any lagging. In the event of difficulty in
indicated, the protection shall be Class 3. achieving this requirement the Project Manager shall
be consulted.
8.6.2 Bonding links shall be provided at each
joint and secured by screws, nuts and shakeproof 8.8.4 Trunking shall be positioned so that
washers. The bonding links shall make contact with adequate clearance is provided for access to the
the metal of the trunking or fitting, and continuity wiring. It is preferred that the covers shall be on the
shall not depend on contact through the screws, nor top or sides of the trunking, but where this is
on removal on site of paint finish from ferrous impracticable covers may be on the bottom, subject
metal. to the approval of the Project Manager. Cable
support shall be as clause 8.5.7.
8.6.3 Factory made connectors shall be used at
joints.
8.9 SUPPORTS AND FIXINGS

8.7 UNDERFLOOR DUCTING AND FLOOR 8.9.1 Where conduit and trunking are not fixed
TRUNKING directly to the building fabric they shall be
suspended in accordance with clause 5.7.
8.7.1 Protection against corrosion shall be Class
3. 8.9.2 A support shall be positioned within
300mm of each bend and conduit box. Conduit
8.7.2 Service outlet boxes and junction boxes boxes shall be fixed to the fabric of the building
shall be constructed from sheet steel of the same independently of the conduit. Where the conduit
finish as the ducting, with top frames adjustable for boxes have a minimum degree of protection of IP44
height at each corner. The frames shall be cast the fixings shall not reduce the protection.
aluminium unless otherwise indicated. Segregation
of the compartments of the ducting shall be 8.9.3 Conduit and trunking shall be fixed in

26 Edition 1 - 2004
Specification 34 Section Eight - Wiring System: Cables in Conduit, Trunking and Ducting

accordance with Table 8A. No shot firing shall be 8.10.9 Conduit shall be cold bent on site with a
used and no drilling or welding of structural suitable bending tool, without deforming its cross
steelwork shall be done without the approval of the section.
Project Manager.
8.10.10 The interval between draw-in boxes in
8.9.4 Screws and nuts shall be non-corrosive conduit systems shall not exceed the
and compatible with the environment in which they recommendations contained in BS 7671 and the IEE
are installed. Guidance Notes.

8.10 INSTALLATION 8.10.11 Unless otherwise indicated, conduit buried

in concrete shall have at least 30mm depth of cover
8.10.1 If the protective finish of any materials and shall be securely fixed to prevent movement
has been damaged, those materials shall either not during pouring and vibrating of the concrete.
be used or any remedial work shall be approved by Conduit buried in plaster shall have at least 5mm
the Project Manager before use. Conduits shall be depth of cover.
clean and free from oil.
8.10.12 Where conduits, trunking or ducting, cross
8.10.2 Holes in trunking shall be drilled, punched expansion and settlement joints in the building
or cut by ring-saw. Trunking shall be free from structure, suitable provision shall be made to allow
sharp edges and burrs. for movement of the structure. Purpose made
expansion couplings shall be used in trunking. The
8.10.3 Connections between trunking and Contractor shall submit his proposals for the
equipment shall be by screwed couplers and bushes, approval of the Project Manager.
flanged couplings or specially fabricated connectors.
Direct attachment of steel trunking to equipment 8.10.13 Where conduit passes through an external
will be permitted only if cable entries are provided wall the conduit shall be plastic and a conduit box
with bushes or grommets or other lining methods shall be fitted on the outer side of the wall. This
approved by the Project Manager. Cutting and shall be filled with an inert, permanently plastic
bending the material of trunking to form flanges for compound having a high insulation value.
connection to equipment will not be permitted.
8.10.14 Conduit, trunking and ducting shall be
8.10.4 Steel conduit shall be connected by means installed in screeds only where indicated, or after
of a coupler and an externally screwed bush at receipt of the Project Manager's approval. Conduit
equipment not provided with screwed entries and at boxes in floors, other than for agreed outlets, are not
trunking. Bushes shall be tightened by spanners; permitted.
pliers and toothed wrenches shall not be used.
8.10.15 Flush floor trunking and underfloor
8.10.5 Cable entries from trunking to distribution ducting shall be straight, level and adjusted in height
boards shall be adequate for cabling from all ways to relate to the finished floor level.
including spares.
8.10.16 Open ends of conduit and ducts shall be
8.10.6 Where a terminal block is to be temporarily plugged immediately they are installed
accommodated in a circular box, an extension ring to prevent ingress of water and solid material. Flush
of sufficient depth to ensure adequate space for the floor trunking and the boxes of underfloor ducting
terminal block and cables shall be fitted to the box. shall be fitted with temporary lids immediately they
are installed, and they shall be maintained as
8.10.7 , The length of thread on the ends of steel effective protection against ingress of water and
conduit shall match that in the conduit fittings or solid material until the permanent lids are fitted after
equipment. Exposed thread is not permitted. screeding is complete.
Running couplings with backnuts may be used with
conduit having Class 2 protection, but where the 8.10.17 The method to be used for forming fire
protection is Class 4 only manufactured running barriers at fire-resistant structural elements such as
joints will be accepted. Exposed thread on running floors and walls shall be submitted for the Project
couplings shall be given a coat of zinc-rich plant. Manager's approval.

8.10.8 Joints between Thermoplastic (PVC) 8.10.18 Installed conduits and ducts shall be
conduit and fittings shall be made with a suitable cleaned internally with a swab before cables are
adhesive, but expansion couplers shall be included. drawn-in.

8.10.19 If the protective finish of conduit,

trunking or ducting is damaged after fixing, the
Edition 1-2004 27
Specification 34 Section Eight - Wiring System: Cables in Conduit, Trunking and Ducting

damage shall be made good in a manner approved 8.12.2 A loop-in form of wiring shall be used as
by the Project Manager. far as practicable or unless otherwise indicated.
Joints in conductors shall be made using insulated
8.11 PROTECTIVE CONDUCTOR terminal blocks complying with the requirements of
clause 12.19.
8.11.1 A protective conductor shall be drawn
through all conduit and trunking systems and 8.12.3 Adequate slack shall be left in cables at
connected to earthing terminals. Each section of expansion joints.
trunking shall be bonded to the protective conductor.
Notwithstanding the provision of a separate 8.12.4 A draw-wire shall be installed, after
protective conductor the continuity of the conduit, swabbing, between each draw-in position where
trunking and ducting shall be to the same standard as conduits are installed for wiring by others.
though they were the sole protective conductors.
8.12.5 Cables forming part of alarm, control,
8.11.2 Where live conductors terminate at, or communication or monitoring circuits shall have
loop into, terminals adjacent to an appliance or identification sleeves at their terminations.
accessory the protective conductor shall be similarly Identification shall be consistent with the relevant
terminated. wiring diagrams.

8.11.3 The earthing terminal of a socket outlet or

other accessory mounted on the lid of steel trunking 8.13 MIGRATION OF PLASTICISER FROM
shall be connected by a separate protective THERMOPLASTIC (PVC) MATERIALS
conductor to an earthing terminal incorporated in the
fixed part of the trunking. 8.13.1 Thermoplastic (PVC) sheathed cables,
including thermoplastic sheath eg LSF, shall be
separated from polystyrene materials to prevent the
8.12 WIRING take up of the cable plasticiser by the polystyrene as
this will reduce the flexibility of the cables. See
8.12.1 No wiring shall be carried out until the Table 8B.
appropriate tests required in clause 19.6.2 have been
done and the Project Manager has given his
clearance for wiring to commence.

28 Edition 1 - 2004
Specification 34 Section Eight - Wiring System: Cables in Conduit, Trunking and Ducting

TABLE 8A CONDUIT AND TRUNKING FIXINGS

1. Fixing of conduit

Location Type of Fixing

Floor screeds Saddles

Buried in plaster or render Crampets or saddles

Above false ceilings Spacer bar saddles

Surface Distance saddles

2. Fixings of saddles, conduit boxes and trunking

Building fabric Type of fixing

Structural steelwork Purpose made clamps, type to be approved by the Project Manager

Non-structural steelwork Set screws and nuts

Concrete, brick or building blocks Plugs and screws

Hollow blocks and pot floors Butterfly spring toggle bolts or gravity bolts

Timber Wood screws

TABLE 8B PLASTERCISER MITIGATION

Location/Fabric Mitigation

Thermal Insulation Thermoplastic cables shall be clipped clear of any insulation made of expanded polystyrene granules

Cable Clips Nylon or polypropylene cable clips shall be used. Polystyrene cable clips are not to be used as they are
softened by contact with thermoplastic (PVC)

Grommets Thermoplastic (PVC) grommets should be used where appropriate. Natural rubber grommets can be
softened by contact with thermoplastic (PVC). Synthetic rubbers are more resistant. Thermoplastic (PVC)
grommets are not affected, but could affect other plastics.

Wood Preservatives Thermoplastic (PVC) sheathed cables shall be covered to prevent contact with preservative fluids during
application. After the solvent has evaporated, the preservative has no effect.

Creosote Creosote shall not be applied to thermoplastic (PVC) sheathed cables as it will cause decomposition,
swelling and loss of pliability.

Edition 1 - 2004 29
Specification 34 Section Eight - Wiring System: Cables in Conduit, Trunking and Ducting

30 Edition 1 - 2004
Specification 34

Section Nine - Wiring System: Multi-core Sheathed

Cables

9.1 CABLES 9.4 INSTALLATION

9.1.1 Cables shall comply with BS 6004, Table 9.4.1 Cables for alarm, control, communication
5 for LV circuits and Table 4 for extra low voltage or monitoring systems shall be fixed by proprietary
(ELV) circuits. Cables shall have copper saddles of suitable nylon or plastic material.
conductors, unless otherwise indicated, and the size
shall be as indicated. 9.4.2 Cables buried in wall finishes, passing
through walls or buried in concrete, including floor
9.1.2 The colour identification of cores shall screeds, shall be protected throughout the length that
comply with BS 7671 or BS EN 60446. For live is buried by heavy duty Thermoplastic (PVC) or
conductors the identification shall extend throughout metal conduit as indicated.
the length of the cables. The additional identification
requirements of clause 9.4.12 shall also be met. 9.4.3 Unless otherwise indicated, conduit buried
in concrete shall have at least 30mm depth of cover,
and shall be securely fixed to prevent movement
9.2 BOXES during pouring and vibrating of the concrete.
Conduit buried in plaster shall have at least 5mm
9.2.1 Joint boxes shall comply with BS 4662 or depth of cover.
BS 6220. Where they are of insulating material the
material shall have the ignitability characteristic "P" 9.4.4 Where conduits cross expansion and
as specified in BS 476. Where terminals are not settlement joints in the building structure, suitable
integral, insulated terminal blocks complying with provision shall be made to allow for movement of
the requirements of clause 12.19 shall be used. the structure. The Contractor shall submit his
proposals for the approval of the Project Manager.
9.2.2 Boxes for accessories shall comply with
the requirements of clause 12.1. 9.4.5 Conduits entering voids shall terminate
not less than 25mm clear of the building fabric.
Open ends of conduit shall be temporarily plugged
9.3 ROUTES AND SEGREGATION immediately they are installed, to prevent ingress of
water and solid material.
9.3.1 Unless the routes of cables are indicated
on the drawings, they shall be determined by the 9.4.6 Where cables pass through joists the
Contractor and approved by the Project Manager number and size of holes shall allow for easy
before work is started. withdrawal and replacement of cables. The diameter
of holes shall comply with the requirements set
9.3.2 Cables shall be parallel with the lines of down in the IEE Guidance Notes. Joists shall not be
the building construction and properly aligned. notched.
Cables passing through joists shall comply with the
requirements set down in the IEE Guidance Notes. 9.4.7 The method to be used for forming fire
Cables buried in wall finishes shall run vertically barriers at fire-resistant structural elements such as
only, unless the Project Manager gives approval to floors and walls shall be submitted for the Project
deviate from this requirement. Manager's approval.

9.3.3 Segregation shall comply with category 9.4.8 Where cables enter a metal enclosure they
"LV" in Table 6A of this specification. shall be protected by grommets or secured by cable
clamps.

9.4.9 Cables shall be looped between outlet

points, and as far as practicable, intermediate joints
shall not be used.

Edition 1 - 2004 31
Specification 034

9.4.10 Where joints are unavoidable they shall be 9.4.12 Cables forming part of alarm, control,
enclosed in boxes. The box shall be permanently and communication or monitoring circuits shall have
clearly labelled to indicate its purpose. Traps, identification sleeves at their terminations.
suitably labelled, shall be provided for permanent Identification shall be consistent with the relevant
access where boxes are concealed. Details of the wiring diagrams.
location of joints and traps shall be included in the
handover documentation. No joints shall be located
in concrete floors. 9.5 PREFABRICATED WIRING
INSTALLATIONS
9.4.11 Cables fixed to the surface, except in
ducts, shall be protected by high impact 9.5.1 The requirements of this Specification
Thermoplastic (PVC) channels up to a height of shall apply to prefabricated wiring installations.
1.5m above floor level.

32 Edition 1 - 2004
Specification 034

Section Ten - Wiring System: Mineral-Insulated

Cables

10.1 CABLES 10.2.8 Compression connectors and associated

dies for the compression tool shall be the correct
10.1.1 Cables shall comply with BS 6207 Part 1. type and size. The tool shall be so designed that the
The size, conductor and sheath material and voltage correct compression must be applied before it can be
rating shall be as indicated. released.

10.1.2 Copper sheathed cables shall have an LSF 10.2.9 Protective conductor tails shall be
outer covering of colour from Table 10A, unless connected to earthing terminals within the enclosure.
otherwise indicated. On larger sizes of cables, where tails are not
provided, the metal sheath shall be connected
directly to the external earthing terminal of the
10.2 TERMINATIONS equipment by a bonding conductor having a cross
sectional area in accordance with BS 7671.
10.2.1 Terminations shall comply with BS 6207
Part 2 and shall be supplied by the same 10.2.10 Core identification shall comply with BS
Manufacturer as that of the cable to which they 7671 for Band I and Band II circuits. The additional
connect, or shall be approved by the cable identification requirements of clause 10.6.9 shall
Manufacturer. also be met.

10.2.2 Unless otherwise indicated, seals shall

have a temperature rating of 105°C. Protective 10.3 JOINTS
conductor tails integral with the seals shall be
provided, where, available from Manufacturers. 10.3.1 Joints in cables shall be kept to a
minimum. Where joints are unavoidable they shall
10.2.3 Appropriate glands shall be used at entries be readily accessible for inspection.
to enclosures. Where cables terminate at accessory
boxes located flush in plaster finish, cable clamps 10.3.2 Straight through joints shall be enclosed
may be used instead of glands; the clamps shall grip within brass jointing sleeves and the conductors
the cable sheath and shall be fixed to the accessory shall be connected by means of solder ferrules or
box. compression joints. Sleeves shall be made by the
same Manufacturer as the cable to be jointed or shall
10.2.4 Glands shall be secured with a locknut at be approved by the cable Manufacturer.
equipment not provided with screwed entries.
10.3.3 Joints, other than straight through, shall be
10.2.5 Pressure sensitive plastic adhesive tape enclosed in circular or adaptable conduit boxes and
shall be applied over exposed cable sheaths and the conductors shall be connected by means of
glands, and protected overall with an LSF shroud. insulated terminal blocks. Conduit boxes shall
The colour of shrouds shall be the same as the cable comply with clause 8.3 and terminal blocks with
covering. clause 12.19. Terminations shall comply with
clause 10.2. Conduit boxes shall be fixed to the
10.2.6 At the terminations of single-core cables, fabric of the building or to cable tray. Where the
gland plates shall comply with clause 2.2.5. For conduit boxes have a degree of protection of IP44 or
three-phase circuits the phase conductors shall be more, fixings shall not reduce that protection.
arranged, if possible, in trefoil formation where they
pass through the enclosure of the equipment. 10.3.4 Joints shall not be buried in the ground
except where indicated. In these cases suitable
10.2.7 Each cable tail shall be long enough to environmental protection shall be incorporated.
connect directly to the terminals of the equipment.

Edition 1 - 2004 33
Specification 034 Section Ten - Wiring System: Mineral-insulated Cables

10.4 ROUTES AND SEGREGATION 10.5.7 Fixings to building fabric shall comply
with Table 10B, unless otherwise indicated. No shot
10.4.1 The routing and segregation of cables firing shall be used and no drilling or welding of
shall comply with clauses 6.1 and 6.2, except that structural steelwork shall be done without the
cables carrying negligible current may be stacked. approval of the Project Manager.

10.4.2 Cables shall not be buried in the building

fabric except where indicated. 10.6 INSTALLATION

10.6.1 The installation of cables shall comply

10.5 SUPPORTS AND FIXINGS with Section 6 as appropriate.

10.5.1 Cables shall be adequately supported 10.6.2 Tools for the manipulation and
throughout their length on cable tray, by fixing termination of cables shall be of a design approved
directly to the fabric of the building or by the means by the cable Manufacturer. Corrugation of the metal
indicated, except where they run through cable ducts sheath or damage to outer coverings will not be
or are buried direct in the ground or in the fabric of accepted. A wood block or wooden faced tool shall
the building. be used to finally dress cables into position.

10.5.2 Cables shall be supported within 300mm 10.6.3 Repairs to a cable's copper sheath will not
of their termination at equipment. be accepted regardless of the extent of the damage.

10.5.3 Cables on tray shall be laid tidily with no 10.6.4 Terminations and joints shall be made in
crossovers, except where essential, and shall be accordance with the Manufacturer's instructions.
fixed with proprietary cable ties designed for the Only clean, dry, plastic filling compound shall be
purpose, or with saddles, or clips. used.

10.5.4 Saddles and clips for cables having an 10.6.5 Where cables are buried direct in the
outer covering shall be LSF covered metal. Bare ground or in cable ducts the installation shall comply
copper saddles and clips may be used for cables with the relevant clauses of Section 6.
without an outer covering.
10.6.6 Cables without outer covering shall not be
10.5.5 The spacing of saddles and clips shall in contact with galvanised finishes, concrete or other
comply with the IEE Guidance Notes. Saddles or material that will cause corrosion.
clips shall be located immediately on each side of
bends in the cable. 10.6.7 Connection to appliances and motors shall
comply with Section 13.
10.5.6 Fixing of saddles to the building fabric
shall be by round-head screws and to cable tray and 10.6.8 Cable guards shall be provided in
non-structural steelwork by round-head screws and accordance with clause 6.10.
nuts. For general areas inside buildings, screws and
nuts shall have appropriate non-corrosive protection 10.6.9 Marking of cables shall comply with
and outside buildings, in plant rooms or other clause 6.11. Cables forming part of alarm, control,
locations as indicated, they shall be of stainless steel communication or monitoring circuits shall have
or brass. identification sleeves at their termination with
specific circuit identification. Identification shall be
consistent with the relevant wiring diagrams.

34 Edition 1 - 2004
Specification 034 Section Ten - Wiring System: Mineral-insulated Cables

TABLE 10A MINERAL-INSULATED CABLE SHEATH COLOURS

Circuit Type Sheath Colour

LV power/lighting etc. Orange

Emergency systems (emergency lighting, etc.) Red

TABLE 10B MINERAL-INSULATED CABLE FIXINGS

Location Type of Fixing

Structural steelwork Purpose made clamps or fasteners, the type to be approved by the
Project Manager

Non-structural steelwork Set screws and nuts

Concrete, brick or building blocks Plugs and round head screws

Hollow blocks Toggle type round head screw fixings

Timber Round head wood screws

Edition 1 - 2004 35
Specification 034

36 Edition 1-2004
Specification 034

Section Eleven - Earthing

11.1 MATERIALS 11.3 CONDUCTORS

11.1.1 All materials and installations shall 11.3.1 Earthing conductors, main earthing bars
comply with BS 7430, the IEE Guidance Notes, and main equipotential bonding conductors shall be
appropriate parts of BS 6651, and standards quoted of the type, size and conductor material as indicated,
therein. and shall comply with clauses 11.3.2 to 11.3.4 as
appropriate.

11.2 EARTH ELECTRODES 11.3.2 Where used to interconnect copper

electrodes the conductor may be bare, but for all
11.2.1 The type and number of earth electrodes other purposes the conductor shall have an extruded
shall be as indicated. Thermoplastic (PVC) sheath.

11.2.2 Unless otherwise indicated, earth 11.3.3 Main earthing bars shall be hard drawn
electrodes shall be rods of 14mm minimum nominal copper bar to BS EN 13601 Grade C101 having
diameter, extensible, copper-clad high-tensile steel minimum dimensions 450mm x 50mm x 6mm.
rods connected together. Copper cladding shall be
molecularly bonded to the steel and shall be not less 11.3.4 Cables shall comply with BS 6004, Table
than 0.25mm thick. Driving heads shall be of high- 1, without sheath, or BS 7211, unless otherwise
tensile steel. A corrosion inhibiting paste shall be indicated.
applied to the threads on rods and couplers. Rods
shall be connected by screwed joints by one of the
following methods: 11.4 JOINTS AND CONNECTIONS

threads shall be roll-formed with a 11.4.1 Joints and connections shall be kept to a
minimum thickness of 0.5mm copper in the minimum.
roots of the thread; couplers shall be of high
strength silicon-aluminium bronze alloy and 11.4.2 All contact surfaces shall be thoroughly
all the threads shall be counterbored at the cleaned and coated with an anti-corrosive electrical
ends so that the couplers completely enclose jointing compound suitable for the conductor
the threads on the rods; materials. For bi-metallic joints a separate abrasive
shall be used to clean each metal.
or
11.4.3 Connections shall be made as follows:
the ends of the rods shall be internally
threaded; couplers shall comprise a copper to main earthing bars by bolted connection
ferrule with the phosphor-bronze coupler of brass, bronze or other non-ferrous
screw. conducting material, but outside buildings,
in plant rooms or other locations as
indicated they shall be stainless steel or
11.2.3 Where earth plates are indicated, they phosphor-bronze set-screws and nuts;
shall be 600mm x 600mm minimum, of solid or
lattice copper not less than 3mm thick. to earth rods by bronze, gunmetal or copper
clamps with phosphor-bronze bolts. Edges
11.2.4 Tape for earth electrodes shall be to BS of clamps shall be rounded;
EN 13601, of the size, length, depth below ground
level and layout as indicated. to earth plates by bolting, or welding.

11.4.4 Termination of cables shall be by

connectors jointed to the cable conductor by the

Edition 1-2004 37
Specification 034 Section Eleven - Earthing

exothermic welding process or by compression 11.6.3 Main earthing bars shall be supported on
joints complying with BS 4579 and clause 3.3.3. insulators suitable for the maximum temperature
under fault condition. They shall be not less than
11.4.5 Joints which are indicated as test points 50mm clear of the building fabric.
shall be bolted or clamped. Joints in tape, other than
at test points, shall be made by the exothermic 11.6.4 For general areas inside buildings, screws
welding process. Overlap of conductors shall be and nuts shall be non-corrosive and compatible with
not less than 100mm. the environment; outside buildings, in plant rooms
or other locations as indicated they shall be stainless
11.4.6 Joints and connections shall be protected steel.
by a coating which will form a seal and exclude
moisture in all weather conditions. At connections 11.6.5 No shot firing shall be used and no
to earth electrodes the coating shall cover all drilling or welding of structural steelwork shall be
exposed conductors. Protective coatings shall be of done without the approval of the Project Manager.
a waterproof, inert, tenacious material.
11.7 INSTALLATION
11.4.7 Bolts, screws, nuts, washers and rivets for
copper conductors shall be of phosphor-bronze, 11.7.1 Electrodes shall be installed in
naval brass or copper-silicon and for aluminium undisturbed ground. The distance between any two
conductors they shall be of stainless steel. The electrodes shall be not less than the sum of the
minimum provision shall be: lengths of the two electrodes.

for flat strip - two M8 bolts; 11.7.2 Excavations and backfilling shall comply
with clause 6.4 as appropriate. Backfill immediately
for sheet metal - two M8 bolts and where surrounding plate electrodes shall have a low
the sheet metal is less than 2mm thick it specific resistivity and good water retention
shall be backed for an area of at least properties, and shall be well compacted.
1000mm2.
11.7.3 Electrode seals shall be provided where
earth rods are to be installed through the base slab of
11.5 INSPECTION PITS a building. As indicated, either: the rods shall be
driven and the seals fitted before the concrete is
11.5.1 Unless otherwise indicated, connection poured; or the seals shall be handed to the Building
between an earth conductor and its associated earth Contractor for him to incorporate into the slab for
electrode system shall be in an enclosure. the rods to be driven at a later date. Ingress of water
shall be avoided when driving the rods.
11.5.2 The enclosure shall have a removable top
cover, which shall be flush with finished ground 11.7.4 Earth plates shall be installed vertically in
level. The enclosure shall be a purpose made an excavated hole, with the top of the plate at a
inspection pit made of concrete, galvanised steel or minimum depth of lm below finished ground level.
plastic material embedded in concrete, as indicated. Where difficulty in achieving this depth is met the
The earth electrode connection shall be just below Project Manager shall be consulted.
the lid of the inspection pit with adequate access for
testing purposes. The enclosure shall be clearly 11.7.5 Installation of conductors shall comply
labelled to indicate the electrodes function and, with Section 6 as appropriate.
where appropriate, its identification number.

11.8 BONDING TO INCOMING SERVICES

11.6 SUPPORTS AND FIXINGS
11.8.1 Bonding to incoming services shall be to
11.6.1 Cables shall be supported and fixed in BS7671.
accordance with Section 5.
11.8.2 Where a service belongs to a Supply
11.6.2 Tapes and bars shall be fixed by spacer Company, the permission of the Supply Company
bar saddles which shall be of non-metallic material shall be obtained before connection is made.
or corrosion resistant alloy, compatible with the
conductors maximum temperature under fault
condition. Fixing of the saddles shall comply with
Table 8 A. The maximum spacing of fixings shall
not exceed 600mm unless otherwise indicated.

38 Edition 1 - 2004
Specification 034

Section Twelve - Wiring Accessories and Small

Equipment

12.1 ACCESSORIES - GENERAL of IP41 when used inside buildings and IP44 when
used outside buildings or at other locations, unless
12.1.1 Accessory boxes used with steel conduit otherwise indicated.
and with mineral insulated cables shall be metal and
those used with multi-cored sheathed cables 12.1.9 Accessory boxes shall be fixed to the
installed in accordance with Section 9 shall be of fabric of the building independently of the
insulating material, unless otherwise indicated. connecting cable or conduit, and as specified for
conduit boxes in Table 8A. Where the accessories
12.1.2 Accessory boxes of insulating material have a minimum degree of protection of IP44 the
shall have the ignitability characteristic "P" as fixings shall not reduce that protection.
specified in BS 476.

12.1.3 Accessory boxes shall be suitable for 12.2 SWITCHES

flush or surface mounting, as indicated. Metal boxes
for general use inside buildings shall be of steel with 12.2.1 Switches shall comply with the relevant
medium category of protection against corrosion; for British Standard for the type of switch indicated.
use in plant rooms and outside buildings and other
locations as indicated they shall be steel with heavy 12.2.2 Switches shall be single pole for single-
category of protection. phase circuits and three pole for three phase circuits,
unless otherwise indicated. Their current ratings
12.1.4 Accessory boxes shall be of adequate shall be as indicated. Lighting switches in
depth to accommodate the accessories without fluorescent or discharge lamp circuits shall be rated
causing compression of the cables. Generally boxes for 20A inductive loads unless otherwise indicated.
shall be 35mm deep, but for lighting switches
installed flush in plaster finish with multi-cored 12.2.3 Wall mounted switches located inside
sheathed cables complying with Section 9, 16mm buildings shall have rocker type actuating members.
depth boxes may be used. Where mounted adjacent to one another they shall
be grouped in a multi-gang box with a common
12.1.5 Earthing terminals shall be fixed inside front plate or in a gridswitch.
each accessory box and on the grids of gridswitches.
The earthing terminal of each grid shall be 12.2.4 Pull cord operated switches installed in
connected by a separate protective conductor to the conduit systems shall be fixed to white moulded
earthing terminal of the box. plastic mounting blocks which in turn shall be fixed
to a circular conduit box. Where the conduit boxes
12.1.6 Front plates of accessories shall be of the are flush with the finish the mounting block shall
material and finish as indicated, but generally the overlap them.
finish of various types of accessories in the same
area shall match. For flush mounting the plates shall
overlap the boxes, and for surface mounting the 12.3 DIMMERS
plate shall match the profile of the box without
overlap. 12.3.1 Dimmers for the control of tungsten
filament lamps shall comply with BS 5518. For
12.1.7 Where pilot lamps are required they shall other dimmers the limits and the methods of
comprise a neon lamp with resistor and a red measurement of radio-frequency interference
coloured lens integral with the accessory, unless generated by the electronic assembly shall be in
otherwise indicated. Pilot lamps shall be wired to accordance with BS EN 55015.
show supply status or load status as indicated.

12.1.8 Accessories with their boxes and front

plates shall provide a minimum degree of protection

Edition 1-2004 39
Specification 034 Section Twelve - Wiring Accessories and Small Equipment

12.4 SOCKET OUTLETS rated at 45A and have a 13A switched socket outlet
with pilot lights for both functions.
12.4.1 Socket outlets shall comply with the
relevant British Standard for the type of outlet 12.10 TELEPHONE CORD-OUTLETS
indicated.
12.10.1 Telephone cord-outlets shall be of the
12.4.2 Socket outlets shall be of the type and type indicated.
rating as indicated. Pilot contacts shall be provided
where indicated.
12.11 SAFETY ISOLATING
12.4.3 Socket outlets shall be switched where TRANSFORMERS
indicated. On socket outlets rated at 13A and
located inside buildings the switches shall be single 12.11.1 Safety isolating transformers shall be
pole and have rocker type actuating members unless fixed type and their enclosures shall provide a
otherwise indicated. minimum degree of protection of IP44. The
nominal rated input voltage shall be 230 volts and
tappings shall be provided on the input winding for
12.5 SOCKET OUTLETS FOR WET alternative input voltages. The output windings
LOCATIONS shall be centre tapped and the tapping connected to
earth.
12.5.1 Socket outlets shall be provided with
covers. Any cover required to achieve total 12.11.2 Cartridge fuses or MCB's shall be
enclosure and to ensure the required degree of provided to protect the input winding and both poles
protection against moisture shall be securely fixed to of each outgoing circuit.
the socket outlet.
12.11.3 Transformers supplying only hand lamps
and bench lamps shall comply with Section E of BS
12.6 PLUGS 3535 and shall have an output voltage of 50 volts
and a rated output of 100VA. One socket outlet
12.6.1 Plugs shall be provided as indicated. Plug shall be mounted on the transformer enclosure and
bodies shall be of metal, plastic or other material as terminals shall be provided within the enclosure for
indicated. two other outgoing circuits.

12.6.2 Plugs rated at 13A shall be of a non- 12.11.4 Transformers supplying portable tools or
resilient material unless otherwise indicated. other equipment shall comply with Section D of BS
3535 and shall have dual secondary windings with
12.6.3 Fused plugs shall be fitted with fuses rated rated outputs of 400VA at 110 volts and 100VA at
as indicated. 50 volts. Two socket outlets shall be mounted on
the transformer enclosure, one for each voltage. In
addition, terminals shall be provided within the
12.7 SHAVER SOCKET OUTLETS enclosure for two other outgoing circuits for each
voltage.
12.7.1 Shaver socket outlets shall be to BS 4573.
12.11.5 Socket outlets for 50 volt circuits shall be
rated at 5 A and for 110 volt circuits they shall be
12.8 FUSED CONNECTION UNITS rated at 16A, and shall be to BS EN 60309-2.

12.8.1 Fused connection units shall be double 12.11.6 A separate terminal shall be provided for
pole switched and fitted with pilot lamps where each outgoing conductor and bunching of
indicated. Fuses shall be rated as indicated. conductors in one terminal will not be accepted.
Conduit entries shall be provided for input and
12.8.2 Front plates shall incorporate a flex outlet output cables.
with a clamp for anchoring the flexible cord, where
indicated. 12.11.7 Transformers for bell or alarm circuits
shall comply with Section B or C of BS 3535, as
appropriate, and shall be suitably rated for the
12.9 COOKER CONTROL UNITS connected load.

12.9.1 Cooker control units shall comply with

BS 4177 and, unless otherwise indicated, shall be

40 Edition 1 - 2004
Specification 034 Section Twelve - Wiring Accessories and Small Equipment

12.12 ROOM THERMOSTATS 12.16 BELLS AND BUZZERS

12.12.1 Room thermostats shall comply with BS 12.16.1 Bells and buzzers shall have contactless
3955 and BS EN 60730 or BS EN 61058. Switches movements and shall not incorporate a transformer.
shall be single pole, single throw, and rated as
indicated. The rated current shall be as indicated. 12.16.2 Bell gongs shall have a minimum
diameter of 75mm unless otherwise indicated.
12.12.2 Thermostats shall be adjustable and shall
have a visible indicator and a calibrated temperature 12.16.3 Bells mounted outside a building shall
scale. Adjustment shall not require a special tool provide a minimum degree of protection of IP54 and
and fixed covers shall be provided to prevent shall have a tapped entry for steel conduit.
tampering by unauthorised persons.
12.16.4 The base and cover of buzzers shall be of
12.12.3 No provision for manual overriding of the plastic material.
thermal switching shall be included, unless
otherwise indicated.
12.17 PUSHES
12.12.4 Thermostats shall be suitable for
mounting direct on to a circular conduit box or 12.17.1 Pushes shall have a current rating of 1A
adaptable box. unless otherwise indicated and shall be suitable for
flush or surface mounting as indicated. Voltage
rating shall be as indicated.
12.13 ELECTRICITY METERS
12.17.2 Boxes and front plates shall comply
12.13.1 Electricity meters shall be of the direct generally with clause 12.1.
connection type complying with the appropriate part
of BS 5685, BS EN 61036 unless otherwise
indicated. 12.18 INDICATORS

12.13.2 Maximum demand meters shall comply 12.18.1 Indicator units for alarm or call systems
with BS 5685 and shall be of the whole current type shall incorporate the number of signals as indicated.
unless otherwise indicated.
12.18.2 Enclosures shall be as indicated.
12.13.3 Meter boards, where required, shall be of
20mm thick wood chipboard complying with BS 12.18.3 Inscriptions shall be as indicated.
5669, Type I.

12.19 TERMINAL BLOCKS

12.14 TIME SWITCHES
12.19.1 Terminal blocks shall comprise
12.14.1 Unless otherwise indicated, time switches connectors contained within a moulded housing
shall be battery backed electronic or self-starting, complying with BS EN 60998.
self-winding, synchronous motor type rated as
indicated. The motor shall be protected by a fuse 12.19.2 Conductors shall be clamped between
which shall be easily accessible. The rated current metal surfaces and no screws shall make direct
of the switch shall be as indicated. contact with conductors. The design shall be such as
to maintain sufficient contact pressure to ensure
12.14.2 Time switches shall be of the connections of negligible impedance at all times.
demountable type.
12.19.3 Metal in contact with conductors shall be
compatible with the conductors. The moulded
12.15 PHOTO-ELECTRIC CONTROL housing shall be of an insulating material suitable
UNITS for the maximum operating temperature of the
conductors.
12.15.1 The sensing unit shall comprise a photo-
conductive cell enclosed in a translucent plastic
dome sealed to a mounting base and have number of 12.20 MOUNTING HEIGHTS
poles and rated current as indicated.
12.20.1 Mounting heights shall be in accordance
with Table 12A unless otherwise indicated.

Edition 1 - 2004 41
Specification 034 Section Twelve - Wiring Accessories and Small Equipment

12.20.2 Where difficulty in locating accessories or

equipment occurs, the Project Manager shall be
consulted

42 Edition 1-2004
Specification 034 Section Twelve - Wiring Accessories and Small Equipment

TABLE 12A MOUNTING HEIGHTS (for accessories and equipment)

Accessories or Equipment Location of Function Height

mm

Lighting switch Location:

general 1350
disabled toilet 1000

Shaver socket outlet 1350

Socket outlet Location:

General 200
Kitchens 1350
homes for disabled or elderly 1000
above worktops 200
external 1350
car parks and garages See Note 4

Data outlet point General 200

1350

Fused connection unit Controlling:

radiant heater - wall 1800 )
radiant heater - focal point 200 ) See also
tubular heater 200 ) Clause
clock 1900 ) 13.1.2
)
Location: )
above worktop 200 )

Cooker control unit 1350

Cooker connection outlet 600

Room thermostat 1600

Telephone outlet 200

Radio/TV outlet 200
Push-button 1350
Fire alarm manual call point 1350
Bell, buzzer or sounder 1900
Key switches 1350

NOTES:
1. Heights are from finished floor level to the centre of the accessory or equipment, except in the case of worktops when the
measurement shall be from the worktop surface.

2. If the specified height of an accessory coincides with the top of tiling, the accessory shall be mounted above the tiling, leaving
a clear gap of 50mm.

3. Where apparatus is located underneath a worktop the accessory shall be mounted 100mm below the underside of the
worktop.

4. In car parks and garages the heights shall comply with appropriate regulations relating to the presence of petroleum vapour.

Edition 1-2004 43
Specification 034

44 Edition 1 - 2004
Specification 034

Section Thirteen - Connections to Appliances and

Motors

13.1 GENERAL 13.4 ROOM HEATERS

13.1.1 The following clauses and Table 13 A 13.4.1 Where a room thermostat controls a
specify standard connection methods for a range of heater, the switch or fused connector shall be
appliances and motors and these methods shall be mounted in a deep box incorporating a terminal
used unless otherwise indicated. For connections to block to enable the cables to the thermostat to be
luminaires refer to Section 14. connected. The terminal block shall comply with
clause 12.19.
13.1.2 Switches or fused connectors shall be
located 150mm from appliances except where 13.4.2 The location of the fused connector for
otherwise stated in the following clauses or radiant heaters in bathrooms shall be as indicated.
otherwise indicated.

13.1.3 A protective conductor shall connect the 13.5 TOWEL RAILS

earthing terminal of each appliance or motor to an
earthing terminal incorporated in the adjacent switch 13.5.1 For wall mounted towel rails intended for
or connector box. connection to the permanent wiring the concealed
wiring shall terminate in a circular conduit box
located immediately adjacent to the conduit entry of
13.2 FLEXIBLE CORDS the towel rail. A dome lid shall be fitted to the
conduit box and be connected to the heater by steel
13.2.1 Flexible cords shall be as Table 13A conduit, and both shall have Class 4 protection.
unless otherwise indicated.
13.5.2 For floor mounted towel rails the steel
13.2.2 Flexible cords shall include a protective conduit shall rise from the floor and connect to the
conductor except where used in a non-conducting heater directly. The cables from the switch or fused
location, and for connection to Class II or Class III connection unit shall be connected directly to the
equipment as defined in BS 7671, unless otherwise terminals on the towel rail.
indicated.
13.5.3 The location of the switch or fused
13.2.3 For connection to appliances which may connector shall be as indicated.
require to be moved for maintenance or cleaning, the
flexible cord shall be 1.5m long.
13.6 COOKERS

13.3 WATER HEATERS 13.6.1 The final circuit wiring shall be concealed
in the building fabric and connect from the cooker
13.3.1 The cable from the switch or fused control unit to a cooker connection outlet located
connector shall be connected directly to the immediately behind the appliance.
terminals on the heater.

13.3.2 The location of the switch or fused 13.7 WASTE DISPOSAL UNITS (DOMESTIC)
connector shall be as indicated.
13.7.1 The fused connection unit shall be located
13.3.3 For instantaneous water heaters mounted adjacent to the sink, and connected to a flex outlet
in bathrooms and kitchens, the conduit shall be under the sink as near as possible to the waste
concealed in the building fabric and terminated at disposal unit via conduit concealed in the building
the heater in a circular conduit box flush with the fabric, unless otherwise indicated.
wall finish. Where possible the connection shall
enter through the back of the heater.

Edition 1 - 2004 45
Specification 034

13.8 SANITARY DISPOSAL UNITS 13.11 PLANT, MACHINERY AND

MOTORS
13.8.1 Units shall be connected from the fused
connection unit to the unit via conduit concealed in 13.11.1 Connections shall allow for vibration and
the building fabric, unless otherwise indicated. adjustment of the motor on its slide rails.

13.11.2 Final connections shall be as indicated.

13.9 EXTRACT FANS
13.11.3 Final connections to small single-phase
13.9.1 The connections to small single-phase items in domestic situations shall be via sheathed
fans shall be as indicated in Table 13A. flexible cords.

13.9.2 Connections to larger fans shall be as

indicated.

13.10 OTHER APPLIANCES

13.10.1 For appliances not covered in the

foregoing, connections shall follow similar methods
unless otherwise indicated.

46 Edition 1 - 2004
Specification 034 Section Thirteen - Connections to Appliances and Motors

TABLE 13A CONNECTIONS TO APPLIANCES

Appliance Maximum Outlet Rating of Cable or Cord Comment

Rating Fuse
(BS1362)
A
Type Pilot Type Size
Lamp mm2
Water Heater
- storage 1kW SFC yes 13 D 1.5 See clause 13.3.1
3kW DPS yes - D 2.5 & note 1

- instantaneous 1kW SFC yes 13 E 1.5 See clause 13.3.3

3kW DPS yes - E 2.5 & note 1
Room Heater
- storage 3kW DPS yes - D 2.5 See clause 13.4.1

- tubular 0.5KW SFC Yes 5 D 1.0

1kW SFC yes 13 D 1.5 See clause 13.4.1
3kW DPS - D 2.5
- radiant 2kW SFC no 13 D 2.5 See clause 13.4.2
Towel Rail - SFC yes 13 E 1.5 See note 13.5
Cooker 32A CC or yes - D
DPS See clause 13.6
45A CC yes - D
Waste Disposal Unit - SFC and FO yes 13 A 1.5
(domestic) A or C See clause 13.7
DPS no _ 1.0
Sanitary disposal Unit - A
- macerator SFC yes 13 1.5 See clause 13.8
- incinerator - SFC yes 13 E 1.0
Extract fan (single phase) SFC yes 3 B 1.0 See clause 13.9
Wall or window mounted See note 2
-without controller 150W SFC A or C
with FO or yes 3 1.0
DPS no - B 1.0 See notes 3 and 4
- with unfused controller SFC A or C
150W with FO or no 3 1.0 See note 5
DPS no - B 1.0 See notes 3 and 4
- with fused controller SFC A or C
150W with FO or no 13 1.5 See note 5
DPS no - B 1.0 See notes 3 and 4
CODINGS - outlets: DPS = 20A double pole switch: SFC = 13A switched fused connector (see clause 12.10)
CCO = cooker connection outlet; FO = flex outlet.

- cables: A = Thermoplastic (PVC/LSF) insulated, non sheathed cables in conduit (as Section 8)
B = Thermoplastic (PVC/LSF) insulated and sheathed (circular) flexible cord
C = Thermoplastic (PVC/LSF) insulated multi-core sheathed cables (as Section 9)
D = 85°C thermosetting (rubber) insulated HOFR sheathed flexible cord
E = 85°C thermosetting (rubber) insulated non-sheathed cables in conduit (as Section 8)

For other applications refer to Table 3B of the IEE Onsite Guide 2002
NOTES:
1. SFC or DPS to be engraved with the legend "WATER HEATER".
2. Applies only when SFC immediately adjacent to fan.
3. Where fan is in the same room as and not more than 2m from SFC, an FO to be located immediately adjacent to the fan.
4. Where fan is more than 2m from SFC, a DPS to be located immediately adjacent to fan.
5. Cable to be routed from SFC via controller to FO or DPS.

Edition 1 - 2004 47
Specification 034

48 Edition 1 - 2004
Specification 034

Section Fourteen - Luminaires and Lamps

14.1 LUMINAIRES 14.1.9 Translucent covers and reflective surfaces

shall be clean at the completion of the Works.
14.1.1 Luminaires shall comply with BS 4533,
BS EN 60598 and with this Section.
14.2 STREET LIGHTING COLUMNS
14.1.2 Emergency lighting luminaires shall
comply also with Industry Standards ICEL 1001, 14.2.1 Street lighting columns shall be
1004, 1006, 1008, 1009 and shall be marked with constructed and installed in accordance with BS
the ICEL certification label. Self-contained 5649 and BS EN 40 and shall be of the type as
emergency lighting luminaires shall be fitted with a indicated. Columns set in ground shall be fitted
means of testing at locations indicated. They shall be with a base plate unless otherwise indicated.
provided with a means of isolating the lamp circuit
for maintenance purposes. (Special provisions may 14.2.2 Each column shall be fitted with a fuse
apply for "self testing" emergency lighting systems). unit providing terminations adequate for the cabling
to be looped in and out and shall be fitted with fuses
14.1.3 Unless otherwise indicated, fixed to BS 88 or MCB, as indicated. Control equipment
luminaires shall be Class I, and hand lamps shall be shall be incorporated as indicated.
Class III rated at 50 volts.

14.1.4 Unless otherwise indicated, enclosures of 14.3 LAMPS

luminaires shall provide a minimum degree of
protection of IP2X when located within buildings 14.3.1 Lamps shall be of the type and rating as
and IP44 when located outside buildings. indicated.

14.1.5 Luminaires, both with and without built-in 14.3.2 All lamps shall be supplied and installed
control gear, shall be "F" marked if mounted on by the Contractor unless otherwise indicated.
flammable surfaces.
14.3.3 Tungsten GLS lamps shall be suitable for
14.1.6 Where specific requirements related to the lamp holders listed in Table 14A.
flame propagation and flammability of translucent
covers are indicated, certificates of tests carried out
on samples of the material shall be submitted to the 14.4 LAMPHOLDERS
Project Manager. The tests shall comply with BS
2782. 14.4.1 General lighting service (GLS)
lampholders shall comply with Table 14A. Other
14.1.7 Terminal blocks for connection of the lampholders shall be suitable for the lamps
supply cables shall be adequate for the size of specified.
conductors forming the loop-in wiring specified in
clauses 8.12.2 and 9.4.9, unless separate tails are 14.4.2 Bayonet lampholders in enclosed
required as in clause 14.8. Terminal blocks shall luminaires shall have the temperature rating T2, as
incorporate a fuse of suitable type and rating unless described in BS EN 61184.
otherwise indicated.
14.4.3 Lampholders for use with flexible cords
14.1.8 Inductive ballasts for fluorescent lamps shall be of the cord-grip type.
shall comply with BS EN 60920 and BS EN 60921.
Electronic ballasts for tubular fluorescent lamps 14.4.4 Lampholders not in a luminaire shall have
shall comply with BS EN 60928 and BS EN 60929. a shade carrier ring.
Ballasts for discharge lamps shall comply with BS
EN 60922 and BS EN 60923. Power factor
correction shall be provided and this shall be to not 14.5 CEILING ROSES
less than 0.85 lagging.
14.5.1 Ceiling roses shall be of insulating

Edition 1 - 2004 49
Specification 034 Section Fourteen - Luminaires and Lamps

material having the ignitability characteristic "P" as 14.7.5 Where luminaires are supported from the
specified in BS 476. Extension flanges shall be structure other than by the conduit system the
fitted to all surface mounted ceiling roses where the supports shall comply with clause 5.7. Where
wiring installation is concealed in the building luminaires are fixed direct to the structure the
fabric. Luminaire supporting couplers shall comply fixings shall be as specified in Part 2 of Table 8 A.
with BS 6972.
14.7.6 Luminaires mounted on, or recessed into,
14.5.2 Where plug-in connections are indicated suspended ceilings shall be supported independently
suitable proprietary socket outlets and plugs shall be of the ceiling system unless otherwise indicated.
provided for mounting onto a circular conduit box or
other arrangement as indicated. 14.7.7 For wall mounted luminaires the
mounting height shall be 1900mm above finished
floor level, measured to the centre of the conduit
14.6 PENDANTS AND CHAIN SUSPENSIONS box, unless otherwise indicated.

14.6.1 Luminaires shall be suspended at the

height indicated. 14.8 WIRING CONNECTIONS

14.6.2 A plain pendant shall include a ceiling 14.8.1 Where luminaires, other than those
rose, flexible cord and lampholder. The flexible covered by clause 14.8.2, are fixed direct to circular
cord shall be three core 1 .Omm2, 85°C heat resisting conduit boxes or are supported by pendants or
Thermoplastic (PVC) insulated and the sheath shall chains, the final circuit wiring shall terminate at a
be white, unless otherwise indicated. terminal block in the conduit box.

14.6.3 A tube pendant shall comprise a ball and 14.8.2 Where luminaires having fluorescent
socket cover to fit a circular conduit box, and steel tubes are fixed direct to circular conduit boxes, the
conduit not less than 20mm diameter. At the final circuit wiring may be terminated within the
conduit entry to the luminaire a backnut shall be luminaire unless otherwise indicated. The wiring
used. Complete pendant assemblies shall be shall enter each luminaire at the conduit entry
protected against corrosion in accordance with nearest to the terminal block and, where a loop-in
clause 8.3.2, except where specific finishes are wiring system is used, leave by the same entry.
indicated. Wiring shall not pass through a luminaire unless the
approval of the Project Manager is given.
14.6.4 A chain suspension shall comprise a hook
cover fixed to a circular conduit box and a chain, 14.8.3 Where luminaires are mounted on, or
having a load carrying capacity not less than twice recessed into, a suspended ceiling, connection shall
the weight of the luminaire. be by flexible cord from a plug-in ceiling rose unless
otherwise indicated. The plug-in ceiling rose shall
be located not more than 500mm from the access in
14.7 SUPPORTS AND FIXINGS the ceiling and shall be firmly supported.

14.7.1 Where fluorescent luminaires 1200mm or 14.8.4 Cables and flexible cords for final
more in length are supported directly by the conduit connections to luminaires shall be suitable for the
system they shall be fixed to two circular conduit operating temperature of the luminaire. Flexible
boxes, both of which shall form an integral part of cords for chain suspensions shall have a white
the conduit system. sheath unless otherwise indicated, and for plain
pendants they shall comply with clause 14.6.2.
14.7.2 Where the weight of a luminaire is
supported by a conduit box or cable trunking the 14.8.5 The size of final connection cables or
fixing of the conduit box or trunking shall be flexible cords shall be as indicated.
adequate for the purpose.
14.8.6 Where mineral-insulated cable is used the
14.7.3 Luminaires fitted with tungsten filament requirements of clause 10.2.2 shall be met.
lamps and having metal backplates shall not be fixed
directly to a conduit box in which a thermoplastic 14.8.7 Cables and cords passing close to a ballast
material is a load-bearing member. within a luminaire shall be suitable for the operating
temperature of the ballast.
14.7.4 Support of luminaires from cable trunking
shall be by means of proprietary clamps or brackets. 14.8.8 Terminal blocks, other than those forming
part of the luminaires, shall comply with clause

50 Edition 1 - 2004
Specification 034 Section Fourteen - Luminaires and Lamps

12.19 and the requirements of clause 8.10.6 shall be luminaire to an earthing terminal incorporated in the
met. adjacent conduit box. Where the final connection is
by flexible cord the protective conductor shall form
14.8.9 A protective conductor shall connect the part of the cord.
earthing terminal or earthing contact of each

TABLE 14A LAMPHOLDERS

Lamp type Rating (watts) Landholders

Tungsten filament upto150W Bayonet B22d

200W Edison screw E27

300W and above Edison screw E40

Edition 1 - 2004 51
Specification 034

52 Edition 1 - 2004
Specification 034

Section Fifteen - Emergency Lighting

15.1 GENERAL equipment shall be suitable for, and optimised to

suit, the batteries provided.
15.1.1 Emergency lighting systems and
equipment shall comply with BS 5266 and ICEL 15.3.2 Battery chargers shall be capable of
1001, 1004, 1006, 1008, 1009 and other relevant recharging the batteries after they have been
standards, and also Section 14. discharged for the specified duration of the system
so that within 14 hours, or other period where
indicated, the batteries can again support the load for
15.2 CENTRAL BATTERIES the specified duration period. This requirement shall
be achieved without exceeding the maximum design
15.2.1 Batteries shall be as indicated and shall charging characteristics of the batteries.
comply with the relevant British Standard.
15.3.3 Instruments shall provide indication of
15.2.2 Batteries shall be contained as indicated. battery voltage, trickle charge and boost charge
Enclosures shall comply with clause 2.2. Insulating currents. Indication shall be provided of battery
covers shall be provided over all cell terminals and charger functioning and battery charger failure.
inter-connections. All leads shall be insulated. Other instruments and alarms and provision for
remote display of alarms shall be provided as
15.2.3 Batteries shall be maintained in good indicated.
condition on site with all necessary precautions
being taken to prevent deterioration. They shall be 15.3.4 Simulation of mains failure shall be by
handed over fully charged at the completion of the means of a tamper-proof switch operated by a
Works. removable key unless otherwise indicated.

15.2.4 All necessary equipment for routine

maintenance as recommended by the Manufacturers 15.4 WIRING
shall be provided with each group of batteries.
15.4.1 The wiring installation shall comply with
the relevant Sections of this specification. The type
15.3 CENTRAL BATTERY CONTROL and size of cables shall be as indicated.
EQUIPMENT
15.4.2 Wiring shall not be drawn into the same
15.3.1 All the control equipment including mains conduit, trunking compartment or ducting
failure relays, contactors, battery charger, inverter compartment as cables of other Band I circuits. The
(where required), protection fuses, control switches, cores of emergency lighting circuits shall not be
instruments and indicators shall be contained in contained within the same multicore cable, flexible
enclosures complying with clause 2.2. All cable or flexible cord as cores of any other circuits.

Edition 1-2004 53
 Specification 034

54 Edition 1 - 2004
Specification 034

Section Sixteen - Potentially Explosive Atmospheres

16.1 STANDARDS AND CODES OF 16.1.3 Installations shall comply with BS EN

PRACTICE 60079, BS 7535 and with other codes and standards
as indicated.
16.1.1 Equipment and installation in potentially
explosive atmospheres shall comply with other 16.1.4 The zonal classification, temperature
Sections of this Specification as applicable and the classification, apparatus group and type of
requirements of the Dangerous Substances and protection shall be as indicated.
Explosive Areas Regulations.
16.2 MINISTRY OF DEFENCE MILITARY
16.1.2 Equipment shall comply with BS 4683, EXPLOSIVES AREAS
relevant parts of BS 4999, BS 5000 and BS 5501,
BS 6941, BS EN 50281, BS EN 50014-50020 and 16.2.1 Equipment and installations, including
60079, and other standards as indicated. Equipment lightning protection, in MOD military explosives
shall be certified by BASEEFA or, with the approval areas shall comply with specific regulations issued
of the Project Manager, by an equivalent testing by the MOD or armed services. Information
authority. Copies of certificates and Manufacturers pertaining to these areas shall be sought from the
instructions shall be submitted to the Project Project Manager.
Manager.

Edition 1 - 2004 55
Specification 034

56 Edition 1 - 2004
Specification 034 Section Seventeen - Lighting Protection of Buildings

Section Seventeen - Lightning Protection of Buildings

17.1 GENERAL adequate isolation shall be as described in BS 6651

unless otherwise indicated.
17.1.1 The installation shall comply with BS
6651 and BS 7430. 17.3.5 Where the reinforcement of a concrete
structure forms the down conductors, exposure of
connection points to the reinforcement will be
17.2 AIR TERMINATIONS carried out by the Building Contractor. The Lighting
Protection Contractor shall make the connections
17.2.1 The type and location of air terminations and carry out testing as described in clause 19.8.1
shall be as indicated. unless otherwise indicated.

17.2.2 Metal framed or metal clad roofs or metal 17.3.6 Connections to earth electrodes from
copings which form part, or all, of an air termination down conductors formed by reinforcing steel or
shall be bonded across joints between constituent concrete clad steel frames will be made by the
parts. The bonding may be carried out by the Contractor. They will comprise copper tape, not less
specialist roofing Contractor but where this is not than 20mm x 3mm, welded onto the steelwork or
the case the bonds shall be made as indicated. No bolted to a welded bracket.
drilling of roofing or coping shall be done without
the approval of the Project Manager.
17.4 JOINTS
17.2.3 Roof fixings shall not affect the integrity
of the roofing and shall be as indicated. 17.4.1 Joints in conductors shall be kept to a
minimum.

17.3 DOWN CONDUCTORS 17.4.2 Joints between conductors of the same

metal, other than at test points, shall be made by an
17.3.1 The type and location of down conductors exothermic welding process. Overlap of conductors
shall be as indicated. No aluminium conductor shall shall be not less than 100mm.
be buried in the ground.
17.4.3 Where an aluminium conductor is joined
17.3.2 Conductors connecting between a test to a copper conductor, one of the following methods
clamp on the outside of a building and an earth shall be used:
electrode shall be sheathed; but conductors a bi-metal connector formed by friction welding of
interconnecting copper electrodes may be left bare. high purity copper and aluminium;
Conductors in other locations shall be sheathed the copper conductor shall be completely sheathed
where indicated. Sheaths shall be of Thermoplastic for at least 100mm of its length with metal strip
(PVC), extruded, shrunk-on or similarly applied and electrolytically compatible with copper and
the colour shall be as indicated. aluminium, and then clamped to the aluminium
conductor.
17.3.3 The Project Manager shall be consulted
where the profile of the building would cause an Bi-metal joints shall not be made at test points nor
overhang or re-entrant loop to be formed in a down between the test point and earth electrode.
conductor.
17.4.4 A test clamp shall be provided in eaph
17.3.4 Metalwork, including metal windows, down conductor except where the earth electrode is
handrails, pipework, ductwork and cables, adjacent the structure below ground. It shall be located lm
to down conductors shall be bonded to them unless above ground level unless otherwise indicated. Test
the distance between them provides adequate clamps shall be of cast material appropriate to the
isolation. The distance necessary to provide conductor material.

Edition 1 - 2004 57
Specification 034 Section Seventeen - Lighting Protection of Buildings

17.4.5 Bonding connections to other metal parts obtained before work is started. The maximum
of the building shall be electrolytically compatible spacings of fixings shall not exceed 900mm. No
with those metal parts. fixings shall be made into joints in masonry.

17.4.6 Screws shall be of the following 17.6.2 Saddles and holdfasts shall be of the
materials: following materials:

for copper conductors: phosphor bronze, naval brass for copper conductors: gunmetal, phosphor bronze
or high-tensile manganese brass; or naval brass;

for aluminium conductors: stainless steel. for aluminium conductors: aluminium, aluminium
alloy or stainless steel.
17.4.7 Joints shall be protected as specified in
clause 11.4.6. Clips shall be either of metal, as above, or of
outdoor grade polycarbonate or polypropylene with
snap-on lids which cannot be inadvertently removed.
17.5 EARTH ELECTRODES Clips and saddles shall have rounded edges and
countersunk screws. Brass components shall not be
17.5.1 Earth electrodes other than the building used.
structure below ground shall comply with clause
11.2 and shall be installed in accordance with clause 17.6.3 For general areas inside buildings, screws
11.7. and nuts shall be non-corrosive and compatible with
the environment; outside buildings, in plant rooms
17.5.2 Inspection pits shall be provided in or other locations as indicated, they shall be of
accordance with clause 11.5. stainless steel.

17.6.4 No shot firing shall be used and no

17.6 FIXINGS drilling or welding of structural steelwork shall be
done without the approval of the Project Manager.
17.6.1 Fixings shall be in accordance with Table Drilling and cutting of the outside fabric of the
17A, but the Project Manager's approval of the type building shall be carried out only after the Project
of clips, saddles and holdfasts to be used shall be Manager has given approval.

TABLE 17A CONDUCTOR FIXINGS (lightning protection)

Building Fabric Type of Fixing

1. Outside Buildinqs:
Masonry and concrete Clips or spacer saddles with nylon or plastic plugs and screws;
holdfast caulked-in;
backplate holdfasts;
inserts built-in to new concrete.
Asphalt Asphalt pads;
purpose made backplate holdfasts.
Metal roofs and copings As indicated.
Sloping roofs Corrugated holdfasts or slate holdfasts, as appropriate;
other fixings compatible with the materials and the environment.
Other roofs As approved by the Project Manager.

2. Inside Buildings:
All types of fabric as Table 8A.

58 Edition 1 - 2004
Specification 034

Section Eighteen - Cathodic Protection

18.1 GENERAL The soil shall be tamped around the anodes and to a
depth of 300mm above them.
18.1.1 Cathodic protection shall comply with B S
7361 and shall be by impressed current unless 18.2.6 Where the soil resistivity is greater than
otherwise indicated. 1000 ohm.cm the backfill shall be coke breeze
which has passed through a sieve with a maximum
18.1.2 Information on the nature of the soil, mesh of 12mm. The resistivity of the coke breeze
whether it is aerobic or non-aerobic and if so shall not exceed 50 ohm.cm before any additive is
whether it contains sulphate reducing bacteria, may made to it. The coke breeze shall be thoroughly
be indicated in the tender documents. If it is not mixed with 5% to 10% by weight of slaked lime.
indicated, the Contractor shall analyse samples of Alternative materials shall only be used with the
soil taken at various locations across the area to be permission of the Project Manager.
protected, ensuring that samples are taken from
areas of imported backfill as well as from
undisturbed ground. Total current demand for the 18.3 SOURCE OF POWER
installation shall be based on the sample having the
lowest resistivity. 18.3.1 The transformer and rectifier units shall be
supplied by a Manufacturer with proven experience
in making equipment for cathodic protection. They
18.2GROUNDBEDS shall be suitable for the full current range to be
expected during the life of the installation.
18.2.1 Groundbeds shall be located within the
areas indicated. 18.3.2 The equipment shall conform with the
requirements of all relevant standards and this
18.2.2 Anodes shall be of silicon iron chrome Specification.
unless otherwise indicated. Each anode shall be
fitted with a cable tail comprising a single-core 18.3.3 Provision shall be included to enable the
polythene-insulated Thermoplastic (PVC) sheathed protection current to be adjusted by control of the
cable not less than 10mm. The connection to the rectifier output and, where there are multipole anode
anode shall be mechanically and electrically sound or cathode circuits, individually in each circuit.
and shall be sealed against ingress of moisture.
Details of the proposed method of connection shall 18.3.4 Each transformer and rectifier unit shall
be submitted for the approval of the Project include a means to indicate the direct current (dc)
Manager. output voltage and the total output current. Where
more than one anode or cathode circuit is supplied
18.2.3 The number and size of anodes in each from the same unit the means to identify the current
groundbed shall be adequate to sustain the required in each circuit shall be provided. A mains supply
current for not less than 20 years, or other period "ON" indicator lamp shall be provided.
where indicated. The Contractor shall provide to the
Project Manager calculations to demonstrate that
this requirement will be met. 18.4 CABLING

18.2.4 Each anode shall be buried so that the top 18.4.1 Cables to anodes and cathodes shall have
is not less than 1.5m below ground level and copper conductors with Thermosetting (Ethylene or
surrounded by not less than 300mm of backfill. Chlorosulphonated Polyethylene Rubber) insulation
and Thermoplastic (PVC) sheaths, with or without
18.2.5 Where the soil resistivity is less than 1000 armouring as indicated.
ohm.cm the backfill shall be soil which has passed
through a sieve with a maximum mesh of 12mm. 18.4.2 Cables shall be sized so that the total
voltage drop in a circuit will not exceed 20% of the

Edition 1-2004 59
Specification 034 Section Eighteen - Cathodic Protection

rectifier output voltage when the maximum current within inspection pits similar to those specified in
anticipated in the life of the installation flows. clause 11.5, or on posts, as indicated. Where a
number of test points are adjacent to each other they
18.4.3 Cables shall be installed in accordance shall be terminated in a common inspection pit.
with the requirements of Section 6.
18.5.3 Where the tests specified in clause 19.13.2
18.4.4 Jointing and terminating cables shall show bonding across joints in pipework or structure
comply with clause 3.7 except that where armouring to be necessary, each bond shall be made by a
is included it need not be bonded. copper tape or cable connected directly to the
flanges by an exothermic welding process. The
18.4.5 Cable connections to cathodes shall be whole of the bond shall be protected in accordance
protected with a material compatible with the with clause 18.4.5.
protective coating of the cathode.

18.5 TEST POINTS AND BONDING 18.6 MARKING

18.5.1 Test points shall be fixed to buried 18.6.1 Marking of cables shall comply with
structure or pipes where indicated. They shall be clause 6.11. In addition markers complying with
fixed by welding, preferably by an exothermic that clause shall be placed above each anode
process. The Project Manager shall approve the inscribed "CATHODIC PROTECTION
proposed method of fixing before work commences. GROUNDBED". The joint to the cable tail from the
anode need not be additionally marked. Test point
18.5.2 Test points shall be connected by inspection pits or posts shall be inscribed
Thermoplastic (PVC) insulated cable to terminations "CATHODIC PROTECTION TEST POINT".

60 Edition 1 - 2004
Specification 034

Section Nineteen - Inspection and Testing

19.1 GENERAL 19.3.5 Equipment shall be disconnected for the

duration of the relevant tests, where necessary, to
19.1.1 Inspection and testing shall be done in prevent damage to components of equipment.
accordance with BS 7671, the associated IEE
Guidance Notes, and the requirements of this
Section. 19.4 POWER CABLES

19.1.2 Inspection shall include a physical check 19.4.1 Tests shall be made immediately on
that all equipment has been securely fixed and that completion of the installation of power cables to
all electrical connections are mechanically sound. demonstrate that the phase sequence is correct at all
end connections.
19.1.3 In addition to the test at the completion of
each installation, certain tests shall be done during 19.4.2 HV cables and, where indicated, LV
the progress of the Works, as required by clauses cables shall be tested in accordance with clause
19.4 to 19.8 inclusive, 19.12 and relevant standards. 19.3.3 as soon as their installation is complete.

19.4.3 Where indicated, the oversheaths of cables

19.2 INFORMATION laid underground shall be given a voltage withstand
test after backfilling of the trenches is complete but
19.2.1 For equipment supplied under the before termination.
Contract, the Contractor shall obtain from
Manufacturers the time/current characteristics of all
protective devices for automatic disconnection of 19.5 ALARM, CONTROL, COMMUNICATION
supply, and provide copies to the Project Manager AND MONITORING CABLES
and to the person or persons carrying out the
inspection and testing, in addition to meeting the 19.5.1 Cables shall be tested as soon as their
requirements of clause 20.5.1. installation is complete to ensure that the cores are
continuous, that they have not been crossed and that
the insulation resistance is satisfactory. Insulation
19.3 TESTING METHODS tests shall cover all permutations between each
conductor, screen, metallic sheath, armour and earth.
19.3.1 The Project Manager shall be notified of
the method to be used for each type of test and the
notification shall be given not less than 28 days 19.6 CONDUIT AND TRUNKING
before the tests are to be made.
19.6.1 Where conduit is cast in-situ in reinforced
19.3.2 - Testing procedures for continuity of concrete it shall be checked for freedom from
protective conductors and equipotential bonding blockage and steel conduit shall be tested for
shall be in accordance with the IEE Guidance Notes. electrical continuity before casting and as soon as
practicable after casting.
19.3.3 Voltage tests on HV cables and, where
indicated, on LV cables, type tested and partially 19.6.2 Steel conduit and trunking systems shall
type tested assemblies and transformers shall be inspected and tested before any wiring is
comply with the requirements of site testing in the installed; underfloor ducting and flush floor trunking
appropriate British Standards. shall be inspected and tested before screeding.

19.3.4 Alternative methods may be proposed for

the approval of the Project Manager, but they shall 19.7 EARTH ELECTRODES
be no less effective than those set out in the British
Standards. 19.7.1 The resistance of each earth electrode,

Edition 1-2004 61
Specification 034 Section Nineteen - Inspection and Testing

whether for earthing of protective conductors, 19.11.1 Installations in potentially explosive

lightning protection or an electrical system, shall be atmospheres shall be inspected and tested in
checked as described in BS 7430 immediately after accordance with all the relevant requirements of this
installation of the electrodes and the results Section and with the requirements of BS EN 60079.
submitted to the Project Manager.

19.12 CATHODIC PROTECTION

19.8 LIGHTNING PROTECTION
19.12.1 Cathodic protection installations shall be
19.8.1 Where the reinforcement of a concrete tested during the commissioning period in
structure is indicated to form the down conductors, accordance with BS 7361.
the electrical continuity of the reinforcing bars shall
be tested after each pour of concrete is completed 19.12.2 Before pipework and structure is covered
(clause 17.3.5 refers). by backfilling, every joint in the protected
metalwork shall be tested. Where the resistance is
19.8.2 At the completion of the whole lightning not sufficiently low in relation to the total circuit to
protection installation it shall be inspected and tested allow adequate current to pass, the joint shall be
in accordance with BS 6651. bonded in accordance with clause 18.5.3.

19.9 EARTH FAULT LOOP IMPEDANCES 19.13 RECORDS AND CERTIFICATES

19.9.1 The measured earth fault loop impedance 19.13.1 Inspection and test results shall be
for each circuit shall be checked. Where the recorded on the forms provided by the Project
maximum value is exceeded, the Project Manager Manager. Two copies shall be submitted to the
shall be consulted. Project Manager within seven days of each test.

19.13.2 When all inspections and tests results are

19.10 EMERGENCY LIGHTING SYSTEMS satisfactory, Electrical Installation Certificates shall
be given to the Project Manager not later than the
19.10.1 Emergency lighting systems shall be date of completion of the Works. The Certificates
inspected and tested in accordance with the "three- shall be given in the form laid down in BS 7671, BS
yearly" inspection and test procedure laid down in 5839 for fire alarm systems and BS 5266 for
BS 5266. emergency lighting systems.

19.13.3 The type of earthing employed, the values

19.11 POTENTIALLY EXPLOSIVE of prospective short-circuit current and earth fault
ATMOSPHERES loop impedance at the origin of the installation shall
be recorded on the Electrical Installation
Certificates.

62 Edition 1 - 2004
Specification 034

Section Twenty - Drawings and Documents by

Contractor

20.1 EXTENT OF PROVISION detailed layout drawings showing sections

through ceiling voids and vertical shafts;
20.1.1 Unless otherwise indicated, the Contractor
shall provide the drawings and documents specified system diagrams, circuit diagrams and wiring
in this Section. diagrams for all installations and equipment.

20.1.2 General layout drawings shall be drawn to 20.2.3 Diagrams shall comply with BS 5070 and
a scale of 1:100 or 1:50 as indicated and detailed BS EN 61082. Interconnection diagrams shall
layout assembly drawings to a scale of 1:20. If more indicate the type of cable, conductor size and
detail is necessary scales of 1:10, 1:2 and 1:1 may be terminal numbering.
used.

20.1.3 The numbers of sets of drawings and 20.3 BUILDER'S WORK DRAWINGS
documents to be supplied shall be as indicated.
20.3.1 Builder's work drawings shall show fully
dimensioned details of all builder's work required in
20.2 INSTALLATION DRAWINGS AND connection with the Works together with the overall
DOCUMENTS size and weight of equipment.

20.2.1 Installation drawings and documents,

including diagrams and schedules, shall show the 20.4 AS-INSTALLED DRAWINGS
details of the Contractor's proposals for the
execution of the Works and shall include everything 20.4.1 As-installed drawings, including diagrams
necessary for the following purposes: and schedules, shall show all the information
necessary so that each installation can be operated,
to illustrate in detail the arrangement of the maintained, inspected and tested so as to prevent
various sections of the Works and to identify danger, as far as is reasonably practicable. They
the various components; shall incorporate the information necessary for the
identification of the devices performing the
to integrate the Works with the detail of the functions of protection, isolation and switching, and
building and other installations. their locations. The values of prospective short
circuit current and earth fault loop impedance at all
20.2.2 Installation drawings shall include: material locations of the installation shall be
recorded on the appropriate system documentation.
general layout drawings showing the location
of all equipment including cable, cable tray, 20.4.2 The drawings shall include those set out in
conduit, trunking, ducting and earth electrodes; clause 20.2.2.

detailed layout drawings showing the location 20.4.3 Circuit details including loading, origin,
of all equipment including cable, cable tray, route, destination and, where buried, the depth
conduit, trunking, ducting in switchrooms and below finished ground level shall be shown for each
plant rooms; cable, conduit, trunking and ducting. Conductor size
assembly drawings of factory built equipment and material and the type of insulation of all cables
and site built assemblies; shall be shown together with the number of cores in
each cable or the number of cables in each conduit,
detailed layout drawings showing the trunking or ducting. Where identification is by
connection of cable, conduit and trunking to colour of insulation or sheath this shall be shown.
equipment; Joints and draw-in boxes shall be shown.

Edition 1-2004 63
Specification 034 Section Twenty - Drawings and Documents by Contractor

20.4.4 Where incoming supply cables are completion of the Works, the Contract number and
installed by others they shall also be shown as the name of the Contractor.
described in Clause 20.4.3.
20.4.13 A draft of each as-installed drawing shall
20.4.5 Drawings shall indicate whether conduit, be submitted to the Project Manager for approval
trunking or ducting is surface mounted, concealed in before final issue is made.
ceiling spaces, in wall chases, in floor screeds or
cast in-situ.
20.5 MAINTENANCE AND OPERATING
20.4.6 All earthing conductors, main INSTRUCTIONS
equipotential bonding conductors, main earthing
terminal or bar, protective conductors shall be 20.5.1 For each electrical installation, system and
identified with function, origin, route, destination, individual equipment forming part of the Works, the
conductor size and material, type of insulation and, Maintenance and Operating instructions shall
where buried, the depth below finished ground level. include:
Test points shall be indicated.
the information specified for Manuals Class D
20.4.7 Earth electrodes shall be identified, in Building Services Research & Information
showing their type, dimensions, material and depth Association (BSRIA) Application Guide 1/87;
below finished ground level. The nature of the soil
and any treatment that has been given to it or special a description of the extent and manner of
fill that has been used in the installation shall be operation, including duration periods of
identified. standby systems;

20.4.8 Details of each item of equipment, a description of the method used for
including luminaires, shall include electrical compliance with Regulation 413-02 of BS
characteristics, classification, degree of protection 7671 together with time/current characteristics
against ingress of solids and liquids, class of for all protective devices for automatic
protection against corrosion and Manufacturer's disconnection of supply;
name and reference.
a copy of any Certificates of Compliance with
20.4.9 Diagrams shall comply with clause 20.2.3 relevant standards or schemes as required by
and, where necessary, they shall be supplemented clauses 1.5.2 and 1.5.3;
with physical arrangement drawings to assist the
location and identification of component parts of comprehensive instructions for the switching
equipment. on, operation, switching off and isolation of
circuits/systems and for dealing with
20.4.10 Drawings of the lightning protection emergency conditions;
system shall include identification of those elements
of the building fabric used as air terminations and instructions for any precautionary measures
down conductors. Details of connection to structural necessary;
steel frames or to the reinforcement of a concrete
structure shall be included. Details of earth instructions for servicing, including frequency
electrodes shall comply with clause 20.4.7. Test and materials to be used, to maintain the
clamps shall be identified. equipment in good and safe condition;

20.4.11 During the course of the Works the the names and addresses of Suppliers of all
Contractor shall maintain a fully detailed record of major components together with the type and
all changes, which shall be available to the Project model reference, serial number, duty rating and
Manager, to ensure the as-installed drawings are in the order number and date.
all respects accurate.
20.5.2 Maintenance and Operating instructions
20.4.12 Each drawing shall be in accordance with shall be indexed and contained in ring binders with
BS 308, or the relevant BS EN ISO document that rigid covers. The name of the site and the Contract
replaced it and delivered in the format and medium number shall be printed on the front and spine with a
required in the Particular Specification. The words suitable identification title (where more than one
"AS-INSTALLED" shall be placed in 19mm block volume is necessary). The date of completion of the
letters adjacent to the title block of each drawing Works shall be included on a flyleaf.
together with the name of the site and the section of
the Works, the title of the installation, the date of

64 Edition 1 - 2004
Specification 034 Section Twenty - Drawings and Documents by Contractor

20.5.3 Copies of Manufacturer's data may be possible suitably protected box files or folders shall
incorporated to supplement the descriptions and be provided, identified in accordance with clause
instructions required in clause 20.5.1 but shall not 20.5.2.
replace them. Only data relevant to the Works shall
be included, and where non-relevant information 20.5.4 A draft of the Maintenance and Operating
appears on the same sheet it shall be clearly marked instructions shall be submitted to the Project
to show that it is not applicable. The information Manager for approval. Any amendments required
shall be cross-referenced within the text and shall be made before the Project Manager accepts
included in the index, and, if possible, it shall be final documentation.
contained in the ring binders. Where this is not

Edition 1 - 2004 65
Specification 034 Section Twenty - Drawings and Documents by Contractor

66 Edition 1 - 2004
Specification 034

Appendix One - List of Standards

The following Standards and other documentation are referred to in this Specification:

1. British Standards

BS 65:1991. Spec for vitrified clay pipes, fittings and ducts, also flexible mechanical joints for use
solely with surface water pipes and fittings.

BS 88. Cartridge fuses for voltages up to and including 1000V a.c. and 1500V d.c.

BS 215. Spec for aluminium conductors, steel-reinforced for overhead power transmission.

BS 308. Engineering Drawing Practice.

Withdrawn. Replaced by various BS EN's.

BS 476. Fire tests on building materials and structures.

BS 1361:1971. Specification for cartridge fuses for a.c. circuits in domestic and similar premises.

BS 1387:1985. Specification for screwed and socketed steel tubes and tubulars and for plain end steel
tubes suitable for welding or for screwing to BS 21 pipe threads.
BS 1494. Specification for fixing accessories for building purposes. Fixings for sheet, roof and
wall coverings.

BS 1710:1984. Specification for identification of pipelines and services.

BS 2782. Methods of testing plastics.

BS 3506:1969. Specification for unplasticized PVC pipe for industrial uses.

BS 3535. Isolating transformers and safety isolating transformers.

BS 3573:1990. Specification for polyolefin copper-conductor telecommunication cables.

BS 3924:1978. Specification for pressure-sensitive adhesive tapes for electrical insulating purposes.

BS 3955:1986. Specification for electrical controls for household and similar general purposes.

BS 4177:1992. Specification for cooker control units.

BS 4345:1968. Specification for slotted angles.

BS 4533. Luminaires.
BS 4573:1970. Specification for 2-pin reversible plugs and shaver socket-outlets.

BS 4579. Specification for performance of mechanical and compression joints in electric cable
and wire connectors.
BS 4660:2000. Thermoplastics ancillary fittings of nominal sizes 110 and 160 for below ground gravity
drainage and sewerage.
Edition 1-2004 67
Specification 034v Appendix One - List of Standards

BS 4662:1970. Specification for boxes for the enclosure of electrical accessories.

BS 4678. Cable trunking.

BS 4683. Specification for electrical apparatus for explosive atmospheres.

BS 4921:1988. Specification for sherardized coatings on iron or steel.

BS 4999. General requirements for rotating electrical machines.

BS 5000. Specification for rotating electrical machines of particular types or for particular
applications.
BS 5042:1987. Specification for bayonet lampholders.
Withdrawn. Replaced by BS EN 61184:1995.

BS 5070. Engineering diagram drawing practice.

BS 5266. Emergency lighting.

BS 5467:1997. Specification for 600/1000V and 1900/3300V armoured electric cables having

thermosetting insulation.

BS 5481:1977. Specification for unplasticized PVC pipe and fittings for gravity sewers.

BS 5501. Electrical apparatus for potentially explosive atmospheres.

BS 5518:1977. Specification for electronic variable control switches (dimmer switches) for tungsten

filament lighting.

BS 5649. Lighting columns.

BS 5669. Particleboard.

Withdrawn. Replaced by various BS EN's.

BS 5685. Electricity meters.

BS 5839. Fire detection and alarm systems for buildings.

BS 6004:2000. Electric cables. PVC insulated, non-armoured cables for voltages up to and including

450/750V, for electric power, lighting and internal wiring.

BS 6031:1981. Code of practice for earthworks.

BS 6121. Mechanical cable glands.

BS 6207. Mineral insulated cables with a rated voltage not exceeding 750V.

BS 6220:1983. Specification for junction boxes for use in electrical installations with rated voltages not
exceeding 250V.
BS 6346:1997. Specification for 600/1000V and 1900/3300V armoured electric cables having PVC
insulation.
BS 6480:1988. Specification for impregnated paper-insulated lead or lead alloy sheathed electric cables
of rated voltages up to and including 33000V.
BS 6485:1999. PVC-covered conductors for overhead power lines.

68 Edition 1 - 2004
Specification 034 Appendix One - List of Standards

BS 6622:1999. Specification for cables with extruded cross-linked polyethylene or ethylene propylene
rubber insulation for rated voltages from 3.8/6.6kV up to 19/33kV.

BS 6651:1999. Code of practice for protection of structures against lightning.

BS 6701:1994. Code of practice for installation of apparatus intended for connection to certain
telecommunication systems.
BS 6724:1997. Specification for 600/1000V and 1900/3300V armoured electric cables having
thermosetting insulation and low emission of smoke and corrosive gases when affected
by fire.

BS 6910. Cold pour resin compound and heat-shrink cable joints in the voltage range up to
l000Va.c. and 1500V d.c.

BS 6941:1988. Specification for electrical apparatus for explosive atmospheres with type of
protection N.

BS 6946:1988. Specification for metal channel cable support systems for electrical installations.

BS 6972:1988. Specification for general requirements for luminaire supporting couplers for domestic,
light industrial and commercial use.
BS 7917:1990. Specification for performance of bonds for electric power cable terminations and joints
for system voltages up to 36kV.

BS 7211:1998. Specification for thermosetting insulated cables (non-armoured) for electric power and
lighting with low emission of smoke and corrosive gases when affected by fire.

BS 7361. Cathodic protection.

BS 7430:1998. Code of practice for earthing.

BS 7535:1992. Guide to the use of electrical apparatus complying with BS 5501 orBS6941 in the

presence of combustible dusts.

BS 7671:2001. Requirements for electrical installations. IEE Wiring Regulations. Sixteenth edition.

BS 7884:1997. Specification for copper and copper-cadmium stranded conductors for overhead electric
traction and power transmission systems.
BS 7888. LV and MV accessories for power cables with rated voltage from 0.6/lkV (Um=1.2kV)
up to and including 20.8/36kV (Um=42kV).
BS 7889:1997. Specification for 600/1000V single-core unarmoured electric cables having
thermosetting insulation.

BS 7919:2001. Electric cables. Flexible cables rated up to 450/750V, for use with appliances and
equipment intended for industrial and similar environments.

BS 8000. Workmanship on building sites.

BS 8110. Structural use of concrete.

BS EN 40. Lighting columns.

BS EN 681. Elastomeric seals. Material requirements for pipe joint seals used in water and drainage
applications.
BS EN 1011. Welding. Recommendations for welding of metallic materials.

Edition 1-2004 69
Specification 034v Appendix One - List of Standards

BS EN 10025:1993. Hot rolled products of non-alloy structural steels. Technical delivery conditions.

BS EN 10111:2002. Metallic and other inorganic coatings. Measurement of mass per unit area. Review of
gravimetric and chemical analysis methods.

BS EN 10113. Hot-rolled products in weldable fine grain structural steels.

Cold-rolled low-carbon steel flat products for cold forming. Technical delivery
BS EN 10130:1999. conditions.

Cold-rolled uncoated low carbon and high yield strength steel flat products for cold
BS EN 10131:1991. forming. Tolerances on dimensions and shape.

Continuously hot-dip zinc coated structural steels strip and sheet. Technical delivery
BS EN 10147:2000. conditions.

Specification for hot-rolled flat products made of high yield strength steels for cold
BS EN 10149. forming.

Cold rolled steel sections. Technical delivery conditions. Dimensional and cross-
BS EN 10162:2003. sectional tolerances.

BS EN 13601:2002. Copper and copper alloys. Copper rod, bar and wire for general electrical purposes.

BS EN 22063:1994. Metallic and other inorganic coatings. Thermal spraying. Zinc, aluminium and their
alloys.

BS EN 50014:1998. Electrical apparatus for potentially explosive atmospheres. General requirements.

BS EN 50015:1998. Electrical apparatus for potentially explosive atmospheres. Oil immersion "o".

BS EN 50016:2002. Electrical apparatus for potentially explosive atmospheres. Pressurized apparatus "p".

BS EN 50017:1998. Electrical apparatus for potentially explosive atmospheres. Powder filling "q".

BS EN 50018:2000. Electrical apparatus for potentially explosive atmospheres. Flameproof enclosure 'd'.

BS EN 50019:2000. Electrical apparatus for potentially explosive atmospheres. Increased safety 'e'.

BS EN 50020:2002. Electrical apparatus for potentially explosive atmospheres. Intrinsic safety 'i'.

BS EN 50183:2000. Conductors for overhead lines. Aluminium-magnesium-silicon alloy wires.

BS EN 50281. Electrical apparatus for use in the presence of combustible dust.

BS EN 55015:2001. Limits and methods of measurement of radio disturbance characteristics of electrical

lighting and similar equipment.

BS EN 60079. Electrical apparatus for explosive gas atmospheres.

BS EN 60269. Low-voltage fuses.

BS EN 60309. Plugs, socket-outlets and couplers for industrial purposes.

BS EN 60439. Specification for low-voltage switchgear and controlgear assemblies.

BS EN 60446:2000. Basic and safety principles for man-machine interface, marking and identification.
Identification of conductors by colours or numerals.

70 Edition 1 - 2004
Specification 034 Appendix One - List of Standards

BS EN 60529:1992. Specification for degrees of protection provided by enclosures (IP code).

BS EN 60598. Luminaires.

BS EN 60730. Specification for automatic electrical controls for household and similar use.

BS EN 60898. Specification for circuit-breakers for overcurrent protection for household and similar
installations.

BS EN 60920:1991. Ballasts for tubular fluorescent lamps. General and safety requirements.

BS EN 60921:1991. Specification for ballasts for tubular fluorescent lamps. Performance requirements.

BS EN 60922:1997. Auxiliaries for lamps. Ballasts for discharge lamps (excluding tubular fluorescent
lamps). General and safety requirements.

BS EN 60923:1996. Auxiliaries for lamps. Ballasts for discharge lamps (excluding tubular fluorescent
lamps). Performance requirements.

BS EN 60928:1995. Auxiliaries for lamps. a.c. supplied electronic ballasts for tubular fluorescent lamps.
General and safety requirements.

BS EN 60929:1992. Specification for a.c. supplied electronic ballasts for tubular fluorescent lamps.
Performance requirements.

BS EN 60947. Specification for low-voltage switchgear and controlgear.

BS EN 60998. Connecting devices for low-voltage circuits for household and similar purposes.

BS 61008. Specification for residual current operated circuit-breakers without integral overcurrent
protection for household and similar uses (RCCBs).

BS EN 61009. Specification for residual current operated circuit-breakers with integral overcurrent
protection for household and similar uses (RCBOs).

BS EN 61036:1997. Alternating current static watt-hour meters for active energy (classes 1 and 2).
Withdrawn. Replaced by BS EN 62053-21:2003.

BS EN 61058. Switches for appliances.

BS EN 61082. Preparation of documents used in electrotechnology.

BS EN ISO 1461:1999. Hot dip galvanized coatings on fabricated iron and steel articles. Specifications and test
methods.

2. Electricity Association Technical Standards (can be downloaded via www.electricity.org.uk)

TS 09-9. Polymeric insulated, combined neutral/earth (CNE) cables with solid aluminium phase
conductors and concentric aluminium wire waveform neutral/earth conductor. EA,
1981, Issue 5.

TS 43-30. Low voltage overhead lines on wood poles. EA, 1981, Issue 2.

TS 43-40. High voltage single circuit overhead lines on wood poles.

EA, 1988, Issue 1.

3. International Electrotechnical Commission

IEC 60502. Power cables with extruded insulation and their accessories for rated voltages from lkV
up to 30kV.

Edition 1-2004 71
Specification 034v Appendix One - List of Standards

4. DE Functional Standard (can be downloaded via www.defence-estates.mod.uk)

Design and Maintenance Guide (DMG) 08. Space Requirements for plant access, operation and maintenance.
DEO, 1996. ISBN 0117727857.

5. IEE Guidance Notes

Guidance Note 1. Selection and Erection of Equipment, IEE 4th Edition, 0852969899.
Guidance Note 2. Isolation and Switching, IEE, 4th Edition, ISBN 0852969902.
Guidance Note 3. Inspection and Testing, IEE, 4th Edition, ISBN 0852969910.
Guidance Note 4. Protection against Fire, IEE, 3rd Edition, ISBN 0852969570.
On Site Guide (BS 7671:2001, 16th Edition Wiring Regulations), IEE, ISBN 0852969872.

6. Industry Standards (can be downloaded via www.icel.co.uk )

ICEL 1001:1999. Scheme of product and Authenticated Photometric Data Registration for Emergency
Luminaires and Conversion Modules. ICEL, 1999.

ICEL 1004:2003. Requirements for the Re-Engineering of Luminaires for Emergency Lighting Use.
ICEL, 2003.

ICEL 1006:1999. Emergency Lighting Guide. ICEL, 3rd Edition, 1999.

ICEL 1008:2001. Risk Assessment Guide. ICEL, 3rd Edition, 2001.

ICEL 1009:2001. Emergency Lighting Central Power Supply Systems Standard and Registration Scheme.
ICEL, 2001.
7. BSRIA

Application Guide (AG) 1/87.1. Operating and Maintenance Manuals for Building Services Installations,
Armstrong, J.H. BSRIA, 1990, ISBN 0860222551.

8. Health and Safety at Work etc. Act 1974. HMSO, 1974, ISBN 0102156832.

9. SI 1966 no. 94. Construction (Working places) Regulations 1966. HMSO, 1966.

10. SI 1988 no. 1057. Electricity Supply Regulations 1988. HMSO, 1988, ISBN 0110870573.

11. SI 1989 no. 635. Electricity at Work Regulations 1989. HMSO, 1989, ISBN 011096635X.

12. SI 1994 no. 3140. Construction (Design and Management) Regulations 1994. TSO, 1994, ISBN
0110438450.

13. SI 2002 no. 2665. Electricity Safety, Quality and Continuity Regulations 2002. TSO,
2002, ISBN 0110429206

14. SI 2002 no. 2677. Control of Substances Hazardous to Health (COSHH) Regulations 2002. TSO, 2002,
ISBN 0110429192.

15. SI 2002 no. 2776. Dangerous Substances and Explosive Atmospheres Regulations 2002 (DSEARR). TSO,
2002, ISBN 0110429575.

72 Edition 1-2004