CODE OF PRACTICE FOR SAFE WORKING ON LOW VOLTAGE SYSTEMS Rev 3

CODE OF PRACTICE FOR SAFE
WORKING ON
LOW VOLTAGE ELECTRICAL
INSTALLATIONS
CIL-CoP-471
Written By Mark Platten
15/06/2011
Reviewed & Updated 31/05/2013 - BS7671 Amendment 2
Reviewed & Updated 11/06/2014 - Signage Updated
Reviewed & Updated 05/01/2015 - BS7671 Amendment 3

CONTENTS
1.0 INTRODUCTION
1.1 General
1.2 Safety
1.3 Company Policy
1.4 Customers Rules
2.0 DEFINITIONS
2.1 Company
2.2 Electrical Installation Components
2.3 System Conditions
2.4 Persons
2.5 Notices and Documents and Equipment
2.6 Safety Locks
3.0 PROCEDURE FOR SAFE WORKING
3.1 General Procedure for Authorising a Nominated Person
3.2 Deputy Authorised Nominated Person
3.3 Work Prior to Energisation
3.4 Energisation Of Equipment
3.5 Work on Equipment After Energisation
3.6 Making Electrical Equipment Safe for Working On
3.7 Safety Precautions Prior to Starting Work
3.8 Work on or adjacent to Live Electrical Equipment
3.9 Safety Precautions After Completing Work
3.10 Work Requiring Permit Issues
3.11 Discretionary Permit Issues
3.12 Access by Other Trades
3.13 Absence of Permit Holder
3.14 Working in the Vicinity of Live High Voltage Equipment
4.0 APPENDICES
4.1 Legislation and Standards
4.2 Work Permit Form
4.3 Limitation of Access Permit
4.4 Operational Instruction form
4.5 Danger Notice
4.6 Caution Notice
4.7 Testing Notice
4.8 Electrical Safety Equipment
4.9 Work Permit – Demarcation Guidelines
4.10 Work Permit Flow Chart
4.11 Energisation Procedure
4.12 Safe Start Form

1.0 INTRODUCTION
1.1 General
The consequences of shock, or serious burns from contact with low voltage systems may
be serious and in some circumstances fatal. The purpose of this Code of Practice
document is to give guidance to staff to prevent death or personal injury to any person from
either contact with electricity or the effects of electrical arcing caused in connection with
work activities.
1.2 Safety
In considering safety, therefore, there are four basic objectives:
(a) To prevent a person receiving electric shock by the use of safe working practices.
(b) To prevent risk of burns by avoiding conditions under which arcing could occur.
(c) To ensure that working parties are fully conversant with the site working
environment, geographical working areas and work content.
(d) To ensure that working parties consist of persons who have adequate knowledge of
the equipment to be worked on, are fully aware of the work to be carried out and are
competent to undertake the required work.
1.3 Company Policy
It is policy of the company that the above requirements for the safety of persons are assured by
the practice of safe working procedures as detailed in Part 3 of this document.
The document is based on the safety requirements of the Legislation and Standards listed in
Appendix 4.1.
This Code of Practice document is to be implemented by all company personnel to ensure:
(a) The safety of all personnel engaged in electrical installation work.
(b) The adequacy and effectiveness of electrical installations.
(c) Compliance with Statutory Regulations.
This document sets down the principles for controlling Electrical Safety in the workplace. Due to
the diverse nature of installations, subsidiary companies and where necessary sites must
develop
their own specific controls for the implementation of the requirements of this document using the
operational instruction detailed in appendix 4.4.
1.4 Customer Rules
This document does not preclude the use of any customer’s own safety rules, provided that
the Authorised Nominated Person is satisfied that they comply with statutory regulations
and provide safe working conditions.
In this case, the Authorised Nominated Person is responsible for ensuring that all company
personnel are instructed in the requirements of the customer’s procedures and the use of their
documentation.
Should the customer’s safety rules be found to be unsatisfactory the Authorised Nominated
Person must inform the customer’s representative and recommend that Cilantro Engineering UK
Ltd. procedures and documents will be used.
In all cases where the customer presents his safety rules for use the agreement between the
company and the customer, over whom procedures and documents are used, shall be in writing.

2.0 DEFINITIONS
2.1 Company
Cilantro Engineering UK Ltd.
2.2 Electrical Installation Components
2.2.1 Circuit Conductor
Any conductor in a SYSTEM which is intended to carry electric current in normal conditions,
or to be energised in normal conditions, and includes a combined neutral and earth
conductor, but does not include a conductor provided solely to perform a protective function
by connection to earth or other reference point.
(Electricity at Work Regs 1989)
2.2.2 Electrical Equipment
‘Electrical Equipment’ includes anything used, intended to be used or installed for use, to
generate, provide, transmit, transform, rectify, convert, conduct, distribute, control, store,
measure or use electrical energy.
(Electricity at Work Regs 1989)
2.2.3 System
‘System’ means an electrical system in which all the electrical equipment is or maybe
electrically connected to a common source of electrical energy, and includes such source
and such equipment.
2.2.4 Extra-Low Voltage (ELV)
A voltage, “normally not exceeding 50V ac or 120V ripple free dc whether between
conductors or to Earth”.
(BS 7671)
2.2.6 Low Voltage (LV)
A voltage normally exceeding extra-low voltage but not exceeding 1000 volts ac or 1500
volts dc between conductors and not exceeding 600 volts ac or 900 volts dc between
conductors and earth.
(BS 7671)
2.2.7 Low Voltage (LV) Electrical Equipment
Equipment which is normally connected to a low voltage electrical supply.
2.2.8 High Voltage (HV)
Any voltage exceeding low voltage.
2.2.9 High Voltage (HV) Electrical Equipment
Equipment which is normally connected to a High Voltage electrical supply.
2.3 System Conditions
2.3.1 Live
Electrically charged by being connected to an electrical supply or having a charge retained
by capacitance.
2.3.2 Dead
Electrically discharged by being disconnected from any electrical supply and not having any
charge retained by capacitance.

2.3.3 Earth
The conductive mass of the Earth, whose electric potential at any point is conventionally
taken as zero. (BS 7671)
2.3.4 Earthed
Connected to Earth by conductors of sufficient current carrying capacity to sustain the
prospective short circuit current at the equipment without damage, until the protective
device has disconnected the circuit, in the event of Earthed equipment becoming
connected to an electrical supply.
2.3.5 Isolated
Electrically disconnected and separated from Live Electrical Equipment by opening of a
switch, and securing by the use of an appropriate lockable device or disconnection of
conductors.
2.4 Persons
2.4.1 Competent Person
A person who has adequate technical knowledge, suitable attitude and experience for the
nature of the work undertaken to prevent danger or injury.
A Competent Person may receive a Work Permit or Limitation Of Access
2.4.2 Nominated Person
A Competent Person who is considered by the company Management to have the
necessary experience, personal qualities and suitable qualifications and competence to
isolate low voltage electrical equipment for the purpose of working safely. A Nominated
Person shall have received instruction and assessment in the procedure for the issue of the
necessary documentation to the working party.
A nominated person can not issue permits until authorised.
2.4.3 Authorised Nominated Person
A Nominated Person who is authorised in writing by his/her Divisional Director or nominee
to undertake the responsibilities of the Authorised Nominated Person at a specific site or a
defined area within that site and accepts those responsibilities.
An Authorised Nominated Person can issue a work permit or limitation of access permit.
2.4.4 Working Party
A Competent Person or persons under the supervision of a Competent Person selected to
carry out specific work on an electrical system, modification or maintenance of electrical
equipment.
2.4.5 Personal Supervision
Control of a working party by a competent person who is present throughout the duration of
the work.
2.4.6 Authorised Person (High Voltage)
A Competent Person who is considered by the company management to have the
necessary experience, personal qualities and training to undertake specified duties and
operations associated with High Voltage work. After successful interview, initial
appointments will be made in writing and will be subject to annual review.
a HV Authorised Person may carry out work and issue safety documentation in line with the
categories identified on his / her authorisation letter.

2.4.7 Senior Authorised Person (High Voltage)
An Authorised or Competent Person who is considered by the company management to
have the necessary experience, personal qualities and training to undertake duties and
operations associated with High Voltage work. After successful interview, initial
appointments will be made in writing and will be subject to annual review.
A HV Senior Authorised Person may carry out work and issue safety documentation in line
with the categories identified on his / her authorisation letter.
2.4.8 Qualifications and Competence
Authorised Nominated Persons and Deputy Authorised Nominated Persons should, as a
minimum be Approved Electrician Grade (as defined by JIB / SJIB) or equivalent and
should be able to demonstrate an awareness of the requirements for Inspection and
Testing of electrical Installations.
2.5 Notices and Documents and Equipment
2.5.1 Approved Voltage Indicator
A Voltage Indictor meeting the requirements of HSE GS 38 ‘Electrical Test Equipment for
use by Electricians’. The Indicator must have test probes with no more than 4mm exposed
tips. The indicator must be used in conjunction with a compatible proving unit. Only Voltage
indicators approved by the company should be used. (See appendix 4.8)
2.5.2 Caution Notice (As Illustrated in Appendices, 4.6)
An approved notice warning of need for caution against interference with electrical
equipment to which it is attached, to prevent such interference causing danger to a working
party.
2.5.3 Danger Notice (As Illustrated in Appendices, 4.5)
An approved notice warning of danger to persons approaching the area or interfering with
the electrical equipment to which it is attached. the notice should indicate the nature of the
danger by wording or by standard symbols. A typical notice is illustrated in Section 4.5.
2.5.4 Work Permit (CIL-11-ES-001), Illustrated in Appendices, 4.2
A work permit for use on isolated low voltage electrical equipment issued by an authorised
nominated person, to a Competent Person in charge of work with which danger is associated.
The work permit will detail the work to be undertaken, the isolation(s) effected, barriers
erected, caution and danger notices posted and specific precautions to be taken.
When the Authorised Nominated Person is the working party he shall issue a work permit to
himself.
2.5.5 Electrical Apparatus Limitation of Access Permit (CIL-11-ES-002), Illustrated in
appendices, 4.3)
A permit for use in areas where there are hazards from electrical equipment but where no
work will be undertaken on that electrical equipment.
2.5.6 Specific Precautions
Details, to be entered on a Work Permit, of actions to be taken to guard against danger
within the working area.
2.5.7 Suitable Tools
All Tools including personal tools must be suitable for the operation for which they are
being used and must be in good condition.
2.5.8 Safety Locks
A lock with a unique key which is used to lock off a switch mechanism in the ‘off’ position or
to lock closed a cover which prevents access to live circuit conductors.

2.5.9 Safety Key
A key which is required to open a closed safety lock. Only one safety key at a particular
site shall operate any safety lock at that site. No safety key shall operate more than one
lock at a site.
2.5.10 Key Safe
A lockable safe for retention of the safety keys, applicable to safety locks which have been
used to render apparatus safe prior to the issue of a work permit.
3.0 PROCEDURES FOR SAFE WORKING
3.1 General Procedure for Authorising a Nominated Person
3.1.1 Each Business unit will maintain a Register of Nominated Persons who will have attended a
training session and successfully completed an assessment on the
implementation of these procedures.
3.1.2 The Nominated Person will be supplied with an Identification Card
3.1.3 Where a Nominated Person is to undertake the duties of an Authorised Nominated Person,
on a particular site or sites, he will be notified in writing by his Operations Director /
Manager.
3.1.4 It is essential that the letter of Authorisation outlines the duties and responsibilities of the
Authorised Nominated Person and the site or sites for which he is authorised, and the
duration of those duties. A new letter must be issued where the work is to extend past the
expiry date on the original letter of authorisation.
3.1.5 Each Operating Unit will monitor the effectiveness of an Authorised Nominated Person by
maintaining suitable records and undertaking periodic review of performance. This should
be undertaken during site visits by branch Qualified Supervisors and Safety
representatives.
3.2 Deputy Authorised Nominated Person
3.2.1 Due to the nature of working arrangements on some contracts it may be advisable in the
interests of safe working and convenience to nominate a Deputy Authorised Nominated
Person.
3.2.2 A Deputy Authorised Nominated Person will only assume responsibility for issue of work
permits in the absence of the Authorised Nominated Person i.e. through sickness, holidays
or other work commitments etc.
3.2.3 Whenever possible, when the Deputy Authorised Nominated Person is requested to issue a
work permit they will endeavour to utilise a common work permit book and will update any
other local records that may be required i.e. permit issue registers, mimic diagrams etc.
3.2.4 In circumstances where the absence from site of the Authorised Nominated Person is
planned, the handover of responsibilities should be a straightforward matter. However,
where absence from site is not planned, records of permits issued should be available to
enable a safe and satisfactory transfer of responsibility to be undertaken.
3.2.5 If any work permits issued by the Authorised Nominated Person require to be cancelled in
his absence by the deputy, then the safety precautions detailed in Section 3.9 should be
reviewed before any such cancellation takes place.

3.2.6 Whilst undertaking the duties of an Authorised Nominated Person, the Deputy will apply the
requirements for safe working strictly in accordance with this document.
NOTE: It is essential for Safe Working that where there are more than one
Authorised Nominated Persons / Deputy Authorised Persons on a contract
that there is a clear operating procedure produced for the contract identifying
the controls to be put in place. (see Appendix 4.4)
3.3 Work Prior To Energisation
During the installation of LV electrical equipment the work may be carried out by Competent
Persons as instructed by their supervisor without any specific authorisation as long as no
electrical supply has been connected to that electrical equipment.
A Safe Start Briefing is to be held each morning prior to any work commencing, to ensure all
operatives are informed of the tasks to be carried out, equipment to be used, changes to the site
from the previous day & any exclusion zones that may be implemented that day. (see Appendix
4.12)
3.3.1 Prior to initial energisation of any LV electrical equipment the Authorised Nominated Person
must determine that the following actions have been completed:
(a) Cleaning out of the LV ELECTRICAL EQUIPMENT and removal of all extraneous
material.
(b) Tightening of all busbar and terminal connections.
(c) Visual inspection and electrical testing of circuits in line with BS 7671 Requirements
for Electrical Installations: -
Continuity of Circuit Protective Conductors and Ring Final Circuit Conductors.
Insulation Resistance.
Polarity.
(d) Fitting of barriers, blanking plates, and closing of doors. Ensuring adequate
distribution board schedules are available.
3.4 Energisation Of Equipment
3.4.1 Wherever possible electrical equipment should not be connected to or energised until all
work on that equipment and associated circuits is complete. The first energisation of LV
electrical equipment will be authorised by the Authorised Nominated Person.
3.4.2 Where it is necessary to energise electrical equipment any outgoing circuits which are
incomplete must be isolated and secured with the use of a padlock, the key for which must
be controlled by the ANP. Alternatively all conductors, including neutral conductors, of the
incomplete circuit should be disconnected within the distribution board, insulated and
labelled.
3.4.3 Immediately after energisation electrical testing must be completed in accordance with BS
7671.
3.4.4 Once the electrical supply to LV electrical equipment has been made Live a Danger Live
notice, must be attached to the LV electrical equipment to prevent interference where
danger may arise. This notice should remain in place until all envisaged installation,
extension or modification work on the LV electrical equipment or systems, which the LV
electrical equipment forms a part of, is complete.

3.5 Work On Equipment after Energisation
3.5.1 The consequences of shock, or serious burns from short circuits, associated with low
voltage systems may be serious and in some circumstances fatal, therefore, work on LV
electrical equipment shall be done whilst it is dead.
Regulation 13 of the Electricity at Work Regs 1989 states the following: “Adequate
precautions shall be taken to prevent LV electrical equipment, which has been made dead
in order to prevent danger while work is carried out on or near that equipment, from
becoming electrically charged during that work if danger may thereby arise”.
Regulation 14 of the Electricity at Work Regs 1989 states the following:
‘No person shall be engaged in any work activity on or so near any live conductor (other
than one suitably covered with insulation material, so as to prevent danger) that danger
may arise unless:
(a) it is unreasonable in all the circumstances for it to be DEAD, and
(b) it is reasonable in all the circumstances for him to be at work on or near it
while it is LIVE; and
(c) suitable precautions (including where necessary the provision of suitable
protective equipment) are taken to prevent injury”.
All conditions must be satisfied to justify ‘live working’.
3.5.2 Any work to be carried out on LV electrical equipment subsequent to it being made live,
which involves the removal of covers, opening of doors, removal of barriers or in any other
way makes possible contact with circuit conductors, with the exception of Live testing, shall
be carried out only after the need to work on or near the live conductors has been justified
by the Authorised Nominated Person and authorised by the a senior Manager of the
Project. A Risk Assessment for the work shall be produced by the Authorised Nominated
Person.
3.5.3 Work Not Permitted
Under no circumstances will the following type of work involving LIVE supplies be permitted:
(a) Disconnection and removal of live incoming supply cables to distribution boards,
isolators etc.
(b) Any modifications to LV electrical equipment that could give access to live circuit
conductors.
(c) Connection / disconnection of outgoing circuit conductors in LV electrical equipment
which gives access to live exposed Busbars or terminals including work inside
Distribution Boards
(d) Cable jointing on live low voltage cables.

3.6 MAKING LV ELECTRICAL EQUIPMENT SAFE FOR WORKING ON
3.6.1 The Authorised Nominated Person who has been requested to issue a work permit to allow
work to be carried out on LV Electrical Equipment which has previously been made live and
where the work exposes the working party to the possibility of contact with circuit
conductors shall:
(a) Identify the work to be done and any LV electrical equipment and circuit conductors
which may be exposed.
(b) Isolate all such circuit conductors and apply safety locks to prevent unauthorised
reconnection
of the circuit conductors and apply caution notices at all points of
isolation, indicating that men are working.
(c) By use of an approved voltage indicator, prove and demonstrate to the working
party that the circuit conductors to be worked on are dead.
(d) Where adjacent equipment remains live apply danger notices indicating the
presence of live electrical equipment. This equipment should have no exposed live
parts.
(e) Produce a work permit detailing the nature of the work, the points where isolation
has been carried out, details of barriers erected, caution and danger notices applied
and the name of the person in charge of the working party.
(f) Determine that the person who is to receive the work permit fully understands the
content of the work permit and signs as recipient and receives a copy of the work
permit.
(g) Show the working party where danger notices have been applied indicating the
presence of live electrical equipment.
3.6.2 Where more than one working party is covered by common circuit isolations, separate work
permits will be issued to each working party and all work permits will be cleared and
cancelled before the removal of caution and danger notices, removal of safety locks and
reenergisation
of any circuit conductors. Work permits will make reference to all other
associated work permits within the specific precautions section.
NOTE: The keys to any safety locks applied will be retained in a key-safe by the Authorised
Nominated Person.
3.7 Safety Precautions Prior to Starting Work
3.7.1 The Competent Person in charge of the working party shall ensure, where necessary, that
the following safety precautions are established prior to starting work under a Work Permit:
(a) Working spaces and access ways in the working area are free from obstruction.
(b) LV electrical equipment to be worked on has been isolated proved to be dead by the
Authorised Nominated Person and caution notices displayed.
(c) All necessary drawings and specifications required for the work are available.

(d) All members of the working party are fully informed and understand the work to be
undertaken.
(e) Members of the working party are competent to perform the tasks assigned to them.
(f) An appropriate permit has been issued covering the work to be undertaken.
(g) The working party understands the conditions and parameters of the permit and is
made aware that these must not be altered, varied or exceeded.
(h) Should the working area be subject to environmental hazards the permit will identify
the hazards present and the specific precautions to be taken.
3.7.2 The person in charge of a working party shall retain in his possession the permit issued to
him until the completion of the relevant work. He shall then sign the clearance section of
the permit and return it to the Authorised Nominated Person.
(Also see 3.13.3)
3.8 Work on or near Live exposed LV Electrical Equipment
Although the foregoing procedures are designed to ensure that any member of a working
party cannot make contact with live circuit conductors, it is acknowledged that under
exceptional circumstances working on or near live exposed conductors may be necessary.
These include:
(a) When it is not practicable to carry out the work with the circuit conductors dead eg
where for the purposes of testing it is necessary for the circuit conductors to be live;
(b) Where other hazards are created by making the conductors dead, such as to other
users of the system, or for continuously operating process plants etc;
3.8.1 Whenever such work is to take place, and subject to justification as detailed in 3.5.2, the
following safeguards must be affected by the Authorised Nominated Person
(a) The use of people who are competent to work in the vicinity of live LV electrical
equipment safely;
(b) The provision of adequate information to the person carrying out the work about the
live circuit conductors involved, the associated electrical system and the
foreseeable risks;
(c) The use of suitable tools, including insulated tools, equipment and personal
protective equipment (PPE) i.e. insulated gloves, goggles;
(d) The use of suitable temporary insulated barriers or screens;
(e) The use of suitable instruments and test probes that comply with HSE GS 38 i.e.
fused leads.
(f) Accompaniment by another person(s) if the presence of such persons could
contribute significantly to ensuring injury is prevented; i.e. competent to isolate in an
emergency.
(g) Effective control of any area where there is danger from live electrical conductors i.e
using barriers and / or replacing covers.

3.9 Safety Precautions after Completing Work
3.9.1 The person in charge of the working party shall ensure that the following restoration work
has been carried out where applicable:
(a) Waste materials, tools and any other extraneous materials have been removed from
inside equipment.
(b) All terminations are tight.
(c) All barriers and covers are in place and secured.
(d) All tools and materials have been removed from the work area.
(e) All LV electrical equipment doors are closed.
(f) All members of the working party have left the working area.
(g) All access doors to work area are locked as necessary.
(h) The WORK PERMIT has been signed as cleared and returned to the Authorised
Nominated Person.
3.9.2 The Authorised Nominated Person shall determine that all necessary tests have been
carried out and documented, extraneous materials removed, temporary barriers removed,
covers fixed, doors closed and the work permit signed as cleared.
3.9.3 The Authorised Nominated Person shall then cancel the work permit issued for the work,
remove caution and danger notices, which have been displayed and remove safety locks
which have been applied.
3.9.4 The circuit conductors which have been isolated will then be energised and tests completed
as required by BS 7671, after which the LV electrical equipment will be left switched ‘ON’ or
‘OFF’ as required.
3.10 Works Requiring Low Voltage Work Permit (CIL-11-ES-001)
The schematic diagram (Appendix 4.9) identifies the circuits or areas where work permits
must be issued following initial energisation of supplies, as amplified below:
(a) Cables and/or bus-duct from first isolation point on the low voltage side of
11kv/400v transformer to LV switchboard.
(b) Generator, including stored power packs, prime mover for generator, cables and/or
bus-duct to LV switchboard.
(c) UPS, including stored power packs, cables and/or bus-duct to LV switchboard.
(d) Low voltage switchboard including outgoing circuit breakers, fuse switches,
miniature circuit breakers etc.
(e) Outgoing cables from low voltage switchboard to remote motors, distribution boards,
control panels etc.
(f) Outgoing cables from 400v TP & N distribution boards to remote three phase
motors, heaters etc.

(g) Any work within plant control panels including incoming or outgoing supply and
control circuits.
(h) Inspection and test activities on any of the above equipment.
The foregoing includes new or maintenance work on main switchpanels requiring switching
operations, locking-off to make safe, fitting of protective barriers etc.
3.11 Discretionary Work Permit Issues
The issue of work permits for areas shown below the dotted line on the attached schematic
diagram (see Appendix 4.9) are discretionary, where in the considered view of the
COMPETENT, NOMINATED or AUTHORISED NOMINATED PERSON, no danger will
arise, subject to safety precautions being taken.
(a) Connection, disconnection or maintenance work on motors, distribution boards and
panels where local isolator facilities are provided adjacent to or forming part of the
equipment.
(b) Connection/disconnection of final circuits from sub-distribution equipment with
means of isolation by withdrawing local fuses and/or miniature circuit breakers.
(c) Connection, disconnection, and maintenance of final circuits and connected
apparatus associated with lighting, power and motor supplies etc, remote from subdistribution
equipment.
(d) Work on final circuits for the purpose of low voltage tests, subject to the appropriate
live working precautions being taken. See section 3.8.
NOTE: Warning notices should be posted at all times when work is being carried out.
3.12 Access by Other Trades
3.12.1 When work is to be undertaken, by persons from other trades, in areas where there is live
electrical equipment which could be interfered with, then access will be limited by the issue
of a Limitation of Access Permit by the Authorised Nominated Person. Areas include
Switchrooms and rooms containing electrical distribution equipment.
3.12.2 Permits to other trades will only be issued to their nominated representative who will be
deemed to be their Competent Person.
3.12.3 The Limitation of Access Permit will detail the nature and limits of the work, specific
precautions to be taken and the date and time after which the permit is invalid. Should the
work be incomplete at this time a new Limitation of Access Permit must be obtained.
3.12.4 The Limitation of Access Permit will be signed as received and understood by the
subcontractors
Competent Person, who on completion or suspension of the work, will sign the
clearance section and return the work permit to the issuer.
3.12.5 On completion of the work The Authorised Nominated Person will arrange removal of
related temporary barriers and cancel the Limitation of Access Permit.
3.13 Absence of Permit Holder
3.13.1 Should the named person to whom a permit is issued leave the workplace containing the
equipment named on the permit, the work must cease.

3.13.2 If it is intended that work should continue after the permit holder has left the workplace,
then the permit must be returned to the Authorised Nominated Person, who will cancel that
permit and issue a new permit to the person who will subsequently be in charge of the
work.
3.13.3 Should a PERMIT holder leave the workplace without returning the permit for cancellation
and it is required that the named work should continue, the Authorised Nominated Person
must review the safety procedures detailed in sections 3.6 and 3.7.
The Authorised Nominated Person will then clear and cancel the record copy of the
PERMIT himself and record the reason for doing so. A replacement permit will then be
issued to the new working party in the normal manner detailed in section 3.7
Every effort must be made to ensure that should the original permit holder return to the
workplace, he is made aware that his permit has been cancelled and that no further work
must be undertaken in relation to that permit.
3.14 Working in the Vicinity of Live High Voltage Electrical Equipment
3.14.1 On some installations circumstances may dictate that high voltage and low voltage
electrical equipment are installed within close proximity.
3.14.2 As soon as any high voltage electrical equipment has been energised and made live, then
access to the vicinity of the live high voltage electrical equipment has to be strictly
controlled.
3.14.3 If there is a company High Voltage Authorised Person on site then they shall ensure that
the necessary controls are exercised in accordance with Cilantro Eng Uk ‘Policy and
Practices for Safe Working on High Voltage Electrical Installations’.
3.14.4 Such controls would normally limit access to the vicinity of high voltage electrical
equipment
under the applicable permits as relevant to the nature of the work to be undertaken as
follows:
ELECTRICAL APPARATUS INSTALLATION LIMITATION OF ACCESS (CIL-11-ES-002)
HIGH VOLTAGE PERMIT TO WORK*
SANCTION FOR TEST*
* NOTE: These permits can only be issued by High Voltage Authorised Personnel.
3.14.5 If there are no company or Customer High Voltage Authorised Persons on site to control
access for work in the vicinity of High Voltage Electrical Equipment, then this function shall
be undertaken by the Authorised Nominated Person with the following limitations:
(a) There must be no exposed live high voltage conductors in the area in which work is
to be undertaken.
(b) All access to the area shall be under cover of a Limitation of Access Permit issued
by the Authorised Nominated Person to a competent person in charge of a working
party. Work must stop if the Competent Person is not present. Where it is deemed
that the nominated representative from another company is not suitably competent
to be in the vicinity of high voltage electrical equipment then the working party must
have personal supervision by a Competent Person.
NOTE: This includes company/Customer Personnel and all other persons
that require access including main/subcontractors.
(c) The Limitation Of Access Permit shall not permit any work on or associated with the
high voltage electrical equipment, switchgear, cables etc, including non electrical
work e.g. working in cable trenches containing LIVE cables to seal duct entries etc.

(d) Work on low voltage electrical equipment in the vicinity of live high voltage electrical
equipment shall be under the general procedures of this document. However, the
Limitation of Access Permit covering such work shall clearly identify the limitation of
the work to be undertaken and any specific safety measures that need to be
adopted in addition to those which would normally be exercised.
(e) The Limitation of Access Permit shall clearly state any work activities which shall
not be undertaken.
(f) Those in receipt of the Limitation of Access Permit must fully understand all the
implications, limitations and ensure strict compliance.
Detail that may be considered to be entered is as follows:
(i) Do not use switchgear for access purposes or as a substitute for scaffolding, steps
or ladders.
(ii) Do not remove cable trench covers.
(iii) Do not touch, stand on or lay tools on cables or cable trays.
(iv) Do not touch or operate any switchgear unless specifically instructed to do so.
(v) Precautions must be taken to avoid liquid ingress to any switchgear, accidental or
otherwise i.e. paint, drinks, solvents etc.
(vi) Keep switchroom locked at all times unless in attendance.
(vii) Do not remove any barriers, safety signs or warning notices.
This list is not exhaustive and should be regarded as suggestion only.
Consultation should be made with a company High Voltage Authorised Person.

4.0 APPENDICES
4.1 Legislation and Standards
Relevant Acts, Regulations, Codes of Practice and Standards, as amended.
4.1.1 Health and Safety at Work etc Act 1974.
4.1.2 Management of Health and Safety at Work Regulations 1999.
4.1.3 Provision and Use of Work Equipment Regulations 1998.
4.1.4 Personal Protective Equipment at Work Regulations 1992.
4.1.5 The Electricity Safety, Quality and Continuity Regulations 2002
4.1.6 Electricity at Work Regulations 1989.
4.1.7 BS 7671: Requirements for Electrical Installations, as amended.
4.1.8 HSG 85 Electricity at Work Safe Working Practices.
4.1.9 HS (R) 25 Memorandum of Guidance on the Electricity at Work Regulation 1989
4.1.10 HSE GS 38 Electrical Test Equipment for use by Electricians
4.2 Example of Work Permit (MAP-11-ES-001)
4.3 Example of Limitation of Access Permit (MAP-11-ES-002)

4.4 Operational Instruction; Control of Electrical Safety
Location(s)………………………………………………………………………………………………
Duration: Start Date ………………. Completion date…………………..
Person in Control of Electrical Safety Procedures. (ANP)(QS) ………………………………
(For contracts with more than one location NICEIC Qualified Supervisor may be person in
control).
Person in control is responsible for ensuring that all operatives are aware of isolation procedures
and has access to appropriate safety equipment via the Authorised Nominated Person including,
but not limited to:-
 Approved Voltage indicator
 Insulated tools
 Safety padlocks
 MCB locking devices
 Multi Hasp locking device
 Key Safe
 Caution Notice
 Danger Notice
 Additional Safety equipment is available upon request through Cilantro Safety
Department
 This includes:-
 Insulated Gloves
 Goggles
 Barriers / rubber screens
Specific controls to be implemented at this location(s) are:-
………………………………………………………………………………………………………………
………………………………………………………………………………………………………………
………………………………………………………………………………………………………………
………………………………………………………………………………………………………………
………………………………………………………………………………………………………………
………………………………………………………………………………………………………………
………………………………………………………………………………………………………………
Project Manager ………………………… Signature………………Date………………
ANP ………………………… Signature………………Date………………
Qualified Supervisor……………………….... Signature………………Date………………

4.5 Danger Notice
4.6 Caution Notice
DO NOT TOUCH

4.7 Testing Notice
4.8 Electrical Safety equipment.
4.8.1 Mandatory for all sites
Voltage Indicator with proving unit.
Martindale V1 13700/G with Proving Unit
Kewtech KEW 1700 with GS 38 option and proving unit
Tools
Screwdrivers should be insulated to 1000V
Pliers should be insulated to 1000V
Safety Locks and Key Safes
Padlocks
MCB locking devices
Key Safe
Safety Lockout Hasps
Safety Signs
Danger Live
Caution Men at work
Caution testing in progress
4.8.2 Additional Equipment to be provided where necessary
PPE (Available from Head Office on Request).
Insulated Gloves
Goggles
Rubber sheet (Available from Head Office on Request).

Voltage Indicator and Proving Unit

4.9 Work Permit – Demarcation Guidelines

4.10 Safe Isolation and Work Permit Flow Chart.
4.10 SAFE ISOLATION and WORK PERMIT FLOW CHART
NO
YES
NO
YES YES
NO
NO YES
NO
NO YES YES NO
YES
Locate and identify the circuit /
equipment to be worked on.
Identify all sources of energy
supply
Does the ANP consider a Work
Permit is required?
No Work Permit
Necessary
Start Work
Isolate, lock off. Prove
circuit / equipment is
DEAD
Display warning
notices.
Start Work
Is the voltage of the circuit
above Low Voltage
Seek advice from HV
Appointed Person, DO NOT
ATTEMPT TO START WORK
Can all the circuits / supplies /
equipment be isolated?
ANP to Justify whether
work can be undertaken
see Section 3.5
Isolate, lock off. Prove
circuit / equipment is
DEAD
DO NOT ATTEMPT
TO START WORK –
Seek guidance from
Head office.
Isolate and lock off as far as
possible, all supplies in
connection with the circuit /
equipment to be worked on.
Is the circuit
/ equipment
dead?
Take all suitable precautions
as detailed in Section 3.6
Issue and Display Permit
to Work and caution
notices
START WORK On completion of work,
return Permit to Work
to the ANP for
cancellation
START WORK

4.11 Energisation procedure
4.11 ENERGISATION PROCEDURE
NO
SATISFACTORY
NO
SATISFACTORY
YES
SATISFACTORY
SATISFACTORY
Prior to Initial Energisation, Ensure all actions have been
completed as per Section 3.3.1
 Equipment cleaned out.
 All connections tight.
 Visual Inspection carried out.
 Dead tests carried out:
1. Continuity of Protective conductors
2. Insulation Resistance
3. Polarity.
 Barriers and covers replaced
INSPECTION & TEST PLAN:-
 Inspection Sheets
 Snag Sheets
 Test Sheets
ANP to ensure that all related Permits to Work have been
cleared and cancelled.
ANP to review completed actions.
ANP to ensure that all outgoing circuits from the Distribution
equipment have been Isolated by locking off, removal of fuses,
or disconnection of the conductors.
ANP to authorise Initial Energisation.
 During Initial Energisation the area must be
controlled.
 Where more than one person is involved, clear
communication MUST be maintained.
INSPECTION & TEST PLAN:-
 Test Sheets
DANGER LIVE notice to be
attached where possibility of
danger may arise.
Live testing to be completed upon Initial
Energisation.
 Earth Fault Loop Impedance.
 Operation of RCD/RCBO if applicable
 Functional testing.
ANP to Isolate
circuit / equipment
until such time as
the test result is
Satisfactory.

CODE OF PRACTICE FOR SAFE WORKING ON LOW VOLTAGE SYSTEMS Rev 3

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