Western Power Plain Document...These Electrical Safety Standards provide the minimum electrical safety principals for activities related to construction, testing, commissioning, operation

HORIZON POWER

Electrical Safety Standards CS# 2305182 © Horizon Power

DOCUMENT CONTROL

Document Owner (May also be the Process Owner)

Name: Mark Van Vuuren

Position: Field Practices Manager

Date: September 2013

Approved By *

Name: Mark Van Vuuren

Position: Field Practices Manager


Authorisation ** Process Owner is hereby vested with

authority and responsibility to manage the process end to end.

Name: Lance Roberts

Position: Manager Safety & Health


Date Created/Last Updated September 2017

Review Frequency *** Every 3 years

Next Review Date *** September 2020

* Must be the Process Owner and is the person assigned authority and responsibility for managing the whole process, end-to-end, which may extend across more than one division and/or functions, in order to deliver agreed business results.

** This person will have the power to grant the process owner the authority and responsibility to manage the process from end to end.

*** Frequency period is dependent upon circumstances– maximum is 5 years from last issue, review, or revision whichever is the latest. If left blank, the default will be 1 year unless otherwise specified.

STAKEHOLDERS

The following positions must be consulted if an update or review is required:

NOTIFICATION LIST

The following positions must be notified of any authorised change:

REGIONAL MANAGERS WORKS DELIVERY COORDINATORS

ASSET MANAGEMENT SERVICES HORIZON POWER CONTROL CENTRE

MANAGER OF SAFETY AND HEALTH ASSET MANAGERS

HORIZON POWER


These Electrical Safety Standards provide the minimum electrical safety principals for activities related to construction, testing, commissioning, operation and maintenance of Horizon Power electrical assets.

These Standards will assist Horizon Power workers and including Workers operating, servicing, and/ or maintaining (SPS) Standalone Power Systems electrical equipment (inclusive of all generating methodologies) involved in managing electrical risks associated with carrying out these activities.

They will govern electrical safety and provide a more suitable match for the diverse breadth and depth of electrical activities in our business.

They have been written to support Horizon Power’s overall safety and health framework and the hierarchy of Acts / Regulations, Codes of Practice, Organisational Policies, Practices and Procedures.

These Standards do not detail all the necessary requirements to carry out activities, but together these standards and other instructions, procedures and operational manuals will provide a structured safe system of work.

Hierarchy of Documentation

WA general workplace safety legislation administered by the regulator WorkSafe WA:

Occupational Safety and Health Act 1984

Occupational Safety and Health Regulations 1996

WA Electrical legislation administered by the regulator EnergySafety WA:

Electricity Act 1945

Electricity Licencing Regulations 1991

Electricity Regulations 1947

In the interest of your own personal safety, and the safety of all Horizon Power workers and the general public it is essential that you read these standards and understand how they relate to your work environment.

These Standards will be regularly reviewed, if there are any queries and suggestions for improvement, then direct your queries to the Field Practices team via the Continuous Improvement Process

Standards for t he sa fe t y o f pe rsons w ork ing fo r Hor i zon

Pow er in t he const r uct i on , t es t i ng , commiss ion ing ,

opera t i on and main tenance of E lec t r ica l Appara t us

HORIZON POWER


Hierarchy of Documentation

Acts & Regulations

Codes of Practice

AS/ANZ Standards

Guidenace Notes

Horizon Power Safety & Health Management

Systems

Horizon Power Electrical Safety

Standards

Horizon Power Work Instructions

Horizon Power Switching Manuals

Horizon Power published technical

standards & guidelines

HORIZON POWER


CONTENTS

1 APPLICATION ........................................................................................... 1-1

1.1 Scope ............................................................................................... 1-1

1.2 Training and Authorisation ................................................................ 1-1 1.3 References ....................................................................................... 1-2

2 DEFINITIONS ............................................................................................. 2-1

3 GENERAL REQUIREMENTS .................................................................... 3-1

3.1 Basic Safety Principles ..................................................................... 3-1

3.2 Hazard identification, faults, emergencies & on-site response ......... 3-1 3.3 Emergencies and On-Site Response ............................................... 3-2 3.4 Hazard Identification and Risk Assessment and Reporting .............. 3-3

3.5 Reporting Of Electrical Incidents ...................................................... 3-3 3.6 First Aid ............................................................................................ 3-3 3.7 Elevated Work Platforms .................................................................. 3-3 3.8 Tools and Equipment ........................................................................ 3-3

3.9 Ladders and Scaffold ........................................................................ 3-4 3.10 Personal Protective Equipment ........................................................ 3-4 3.11 Permission to Work .......................................................................... 3-4 3.12 Handover Certificates ....................................................................... 3-5

3.13 Safety Observers .............................................................................. 3-5 3.14 Entry to Substations ......................................................................... 3-5

3.15 Commissioning testing apparatus and underground cables ............. 3-5 3.16 Documentation and Records ............................................................ 3-6 3.17 Commissioning program and safety compliance review ................... 3-6

3.18 Safety rules for testing and / or commissioning electrical apparatus 3-8 3.19 Energising Electrical Apparatus ........................................................ 3-9

3.20 Work on Other Authorities’ Apparatus .............................................. 3-9

4 GENERAL SWITCHING REQUIREMENTS ............................................... 4-9

4.1 High Voltage Switching and Earthing ............................................... 4-9 4.2 Operating Authority ........................................................................... 4-9 4.3 Switching Schedules (Program) ....................................................... 4-9 4.4 Switching ........................................................................................ 4-10

4.5 Fault Switching ............................................................................... 4-10 4.6 Isolations under fault conditions ..................................................... 4-10 4.7 Best Practice of Switching .............................................................. 4-13 4.8 PAUSE: What has to be done? ...................................................... 4-13

4.9 PAUSE: Now check existing conditions. ......................................... 4-14 4.10 Electrical Hazards ........................................................................... 4-14 4.11 Shock ............................................................................................. 4-14

4.12 Arc Flash ........................................................................................ 4-15 4.13 Blast ............................................................................................... 4-15 4.14 Step Potential ................................................................................. 4-16 4.15 Touch Potential ............................................................................... 4-17 4.16 Electrical Apparatus Labels ............................................................ 4-17

5 NETWORK TAGS .................................................................................... 5-18

6 ISOLATION OF ELECTRICAL APPARATUS ........................................... 6-1

HORIZON POWER


7 EARTHING / SHORT CIRCUITING (BOXED IN) ....................................... 7-1

7.1 Program Earths ................................................................................ 7-1 7.2 Working Earths (Boxed in) ................................................................ 7-2

7.3 Earthing / Shorting Equipment Check ............................................... 7-2 7.4 Electromagnetic Induction ................................................................ 7-2

8 WORK PERMITS ....................................................................................... 8-3

8.1 Dead Access/Isolate, De-Energised, Proved De-Energised and Earthed ....................................................................................................... 8-3

8.2 Vicinity or Live Access ...................................................................... 8-4 8.3 Testing .............................................................................................. 8-4 8.4 Electrical Apparatus Declared Out of Use ........................................ 8-5

9 APPROACH TO ELECTRICAL APPARATUS .......................................... 9-5

9.1 Danger Zone ..................................................................................... 9-5 9.2 Safe Approach Distance (SAD) ........................................................ 9-6 9.3 Authorised Persons .......................................................................... 9-9

9.4 Safe Approach Distance (SAD) ........................................................ 9-9

10 HIGH VOLTAGE ...................................................................................... 10-1

10.1 General ........................................................................................... 10-1 10.2 Remote or Automatically Controlled Electrical Apparatus .............. 10-1

10.3 Approach to Cables ........................................................................ 10-1 10.4 Live High Voltage Work .................................................................. 10-1

10.5 Dead High Voltage Work ................................................................ 10-2

11 LOW VOLTAGE ....................................................................................... 11-1

11.1 General ........................................................................................... 11-1 11.2 Live Low Voltage Work ................................................................... 11-1 11.3 Dead Low Voltage Work ................................................................. 11-2

HORIZON POWER


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HORIZON POWER SECTION 1 Page 1-1


1 APPLICATION

These Standards shall be followed by all persons who work on or near Horizon Power’s electrical apparatus.

Safety is the priority value for all aspects of the business

These Standards shall be followed to ensure:

Safety of Horizon Power workers and the public.

Safety and security of Horizon Power’s plant, public and property.

Continuity and reliability of supply.

1.1 Scope

These Standards cover basic electrical safety principles for people working on or near to Horizon Power’s electrical apparatus.

These Standards underpin work instructions, procedures and standards.

Shall is to be interpreted as mandatory and, Should is to be interpreted as advisory or discretionary.

Note: Where these Standards make reference to Person or Persons, read as including HE / HIM / MAN / SHE /HER /WOMAN /THEM.

1.2 Training and Authorisation

Persons who are required to work on or near Horizon Power’s electrical apparatus shall not do so unless they:

Have been appropriately trained for the work they intend to do

Have competency in rescue and resuscitation where required

Are authorized and deemed competent by Horizon Power to carry out that work

To maintain authorisation, Compliance Auditing and Work Skills assessments shall be undertaken at regular intervals and cover as a minimum knowledge, skills and attitude necessary for an individual to perform specified activities and tasks.

Refresher training shall be conducted where deficiencies in following safety instructions, work procedures, concepts or techniques are found during Work Skills assessments.

Refresher training may be done on the work site in conjunction with Work Skills assessments or Compliance Audits.

SECTION 1 HORIZON POWER Page 1-2


1.3 References

National Electricity Network Safety Code (ENA NENS 01)

National Guidelines for Safe Access to Electrical and Mechanical Apparatus (ENA NENS 03)

National Guidelines for Safe Approach Distances to Electrical Apparatus (ENA NENS 04)

Occupational Safety and Health Regulations 1996

Occupational Safety and Health Act 1984 – Reprinted as at June 2005

Horizon Power Network Permit to Work Training Manual

Horizonpower Instruction Manual / Powerlink – Safety – Field Practice Manuals

Horizon Power Switching Rules

Horizon Power Switch Gear Instruction Manual



2 DEFINITIONS

Approved

Having the appropriate Horizon Power endorsement in writing for a specific function.

Authorised Person

A competent person with the delegated authority to perform the duty concerned on behalf of Horizon Power.

Brownfield site

An operational site undergoing enhancement and expansion work (that remains under the overall control of a primary system operating authority) that has sections made non-connectable under an Electrical Access Permit by the physical removal of conductors. Control of the non-connectable plant may be delegated by the primary operating authority to either a construction authority or a commissioning authority via a formal handover certificate.

Caution Tag

An approved notice that reads “CAUTION”

Cable

Means an insulated conductor or two or more such conductors laid together, whether with or without fillings, reinforcements or protective coverings.

Competent Person

Means a person having the skills, knowledge and attributes a person needed to safely complete a task.

Conductor

Means a wire, cable or form of metal designed for carrying electric current including neutrals and earths.

Connectable

Apparatus capable of being connected to the live system by switching of an isolating device.

Connected

Joined together by a conductor capable of carrying electrical current for its required function or purpose by either physically clamping or bolting conductors together or closing a circuit breaker, switch or similar device.



Control Authority

Means the representative who is responsible for the control of the electrical apparatus. Typically these include:

Construction authority;

Commissioning authority; or

Operating Authority

Third party.

Controller

An authorised person who co-ordinates switching, preforms switching by remote control, records and controls the issue of work permits.

Commissioning

The process by which new equipment/apparatus is accepted energised by the Operating Authority.

Danger

The presence of risk to health and/or risk to bodily harm.

Danger Tag

An approved notice that reads “DANGER - DO NOT OPERATE”

Danger Zone

The area surrounding live electrical equipment, such as power lines, that ordinary persons, other equipment and materials must not enter.

De-energised

Means that the electrical supply to Electrical Plant and Equipment has been isolated but not earthed.

Discharged (electrical)

Means conductors, which have been connected to earth to remove any stored electrical energy.

Earth

The general conductive mass of earth, the electric potential of which, at any point, is conventionally taken as zero.



Earthed

Means directly electrically connected to the general mass of earth to ensure and maintain the effective dissipation of electrical energy.

Earthing Equipment

Means approved equipment fitted in an approved manner for earthing electrical apparatus.

Electrical Access Permit (EAP)

Horizon Power’s standard form that authorises access to, and work on, an electrical apparatus that has be made safe through isolating and earthing (HV) or short circuiting (LV)

Electrical Apparatus

Means any electrical machinery or equipment (including primary and secondary) including overhead lines, underground cables and substation equipment, which are live or can be made live. It can also mean equipment used in the generation or supply of electricity that has the ability to rotate, or is pneumatic or hydraulic in nature, or contains stored energy through mechanisms, liquid or gas stored within the equipment.

Electricity Network

Means transmission and distribution systems consisting of electrical apparatus, which are used to convey or control the conveyance of electricity between generators’ points of connection and customers’ points of connection.

Energised

Means connected to a source of electrical supply.

Emergency Service Personnel

Trained personnel from organisations which ensure public safety and health, this includes police, ambulance, fire and rescue services.

Equipotential Bonding

Equipotential bonding - commonly referred to as bonding - is a very important measure in reducing the risk of equipment damage and personal injury. Bonding involves joining together all metalwork and conductive items that are or may be earthed so that it is at the same potential (voltage) everywhere.

Extreme Emergency

Situation that presents an immediate threat to life, property or the environment.

Greenfields Site

A whole site that is not connectable to Horizon Power’s operational site.



Handover Certificate

Means a certificate used to transfer responsibilities between control authorities for any defined part of apparatus.

High Voltage or HV

A voltage exceeding 1000 volts AC or 1500 Volts DC.

Instructed Person

Means a person adequately advised or supervised by an authorised person to enable them to avoid the dangers which electricity may create.

Insulated

Means separated from adjoining conducting material by a non-conducting substance, which provides resistance to the passage of current, or to disruptive discharges through or over the surface of the substance at the operating voltage.

Incident

An incident is something that happens, often something that is unpleasant.

An instance of something happening; an event or occurrence.

Isolated

Means disconnected from all possible sources of electrical supply and needing a deliberate planned physical movement to make the electrical apparatus live.

Isolating Device

A device for rendering plant and electrical apparatus isolated.

Link, Isolator or Disconnector

Means all electrical apparatus other than circuit breakers for disconnecting electrical conductors.

Isolation Point

An isolating device that has been positioned off, remote operation disabled, has a danger tag fitted and is assessed as a suitable step in the process of making safe for access purposes.

Issuing Officer (IO)

An authorised person who is responsible for issuing and cancelling work permits.

Live

Means energised or subject to hazardous induced or capacitive voltages.

https://www.collinsdictionary.com/dictionary/english/happen

https://www.collinsdictionary.com/dictionary/english/unpleasant



Live Line Stick. (Hot Stick)

Means an approved, rated and tested insulated stick for use on live high voltage electrical apparatus.

Live Work

Means all work performed on components of electrical apparatus, not isolated, nor proved de-energised or short-circuited earthed.

Low Voltage or LV

A voltage less than 1000 volts AC or 1500 volts DC

Mobile Plant

Means cranes, elevating work platforms, tip trucks or similar plant, any equipment fitted with a jib or boom and any device capable of raising or lowering a load.

Near

Outside the Safe Approach Distance (SAD) where there is a reasonable possibility of a person, either directly or through any conducting medium, coming within the relevant Safe Approach Distance (SAD).

Network

An interconnected system to transmission and or distribution conductors and electrical apparatus.

Note: “Network” and “system” can be used interchangeably.

Network Operator

Means the owner, controller or operator of an electricity network.

Operating Agreement

Provides a statement of condition status of apparatus within and between separate network operators.

Operation Stick

Means an approved insulating stick for use on Low Voltage apparatus.

On

Working anywhere inside the Safe Approach Distance (SAD)

Person in Charge

Means a person who is responsible for the work being carried out by a work party.



Program Earth

Means approved earthing and short circuiting equipment applied to electrical apparatus, as a requirement for the issue of a work permit.

Recipient in Charge

Means the authorised person who is responsible for the work being carried out by a work party using a work permit.

Safe Approach Distance (SAD)

Means the minimum separation distance that shall be maintained by a trained and competent person, mobile plant (including its load) or any object (other than insulated objects designed for contact with live conductors) from electrical apparatus.

Safe

Means not posing an unacceptable risk to life, health or property.

Safety Observer

Means a competent person assigned by the ‘person in charge’ and whose sole function is to observe and warn against unsafe approach to live electrical apparatus or other unsafe conditions.

SCADA

Supervisory Control and Data Acquisition

Shall

Is to be interpreted as “Mandatory”.

Short Circuiting

Means the connecting together of conductors by approved equipment so that an electrical voltage cannot exist between them.

Should

Is to be interpreted as “advisory or discretionary”.

Substation

Means a switchyard, terminal station or place at which high voltage supply is converted, or transformed or switched.

Switch

Means electrical apparatus designed to make or break normal load current and make fault current.



Switching

The operation of circuit breakers, isolators, disconnectors, fusses or other method of making or breaking an electrical circuit, this also include the application and removal of program earths.

Switching Operator

Means a person authorised to carry out switching operations within their limits of authority on networks and generating plant and equipment.

Testing

The process by which the performance of the equipment is identified prior to the equipment becoming energised.

Vicinity

Means work Outside the Safe Approach Distance (SAD) where there is no reasonable possibility of a person, either directly or through any conducting medium, coming within the relevant Safe Approach Distance (SAD).

Work Permit

Means any form of authorisation, which allows access to, work on or near, or testing of electrical and mechanical apparatus.

Working Earth

Means approved earthing and short circuiting equipment applied to electrical apparatus, following the issue of a work permit.






3 GENERAL REQUIREMENTS

Scope

The intention of the Electrical Safety Standards (ESS) is to provide Horizon Power with a set of standards and procedures that govern all access to Horizon Power electrical apparatus, assets.

The standards within the ESS are intended for all Horizon Power workers and including Workers operating, servicing, and/ or maintaining (SPS) Standalone Power Systems electrical equipment (inclusive of all generating methodologies), who work on or near the Horizon Power electrical assets, including extra low voltage systems (as defined in AS/NZS 3000:2007), street lighting and metering services.

3.1 Basic Safety Principles

3.1.1 All HV and LV electrical apparatus shall be regarded as live until Isolated, proved to be de-energised, earthed and / or short-circuited where practicable, and a work permit issued according to the procedures approved by Horizon Power.

3.1.2 Rescue equipment must be positioned for use when working on or close to bare live or de-energised electrical apparatus.

3.1.3 Personnel who work on or near live or de-energised electrical apparatus and their direct assistant(s) must be trained in the use of rescue equipment and resuscitation.

3.2 Hazard identification, faults, emergencies & on-site response

Fault operations and primary response procedures are high priority activities that manage hazards to make the electrical system, apparatus, and asset safe.

All personnel must ensure that their own safety and the safety of others are not placed at risk.

Prior to commencing any work on or near electrical apparatus, hazards must be identified, risk assessed and controlled.



3.3 Emergencies and On-Site Response

Any Horizon Power authorised worker, whether on or off duty, who finds or is advised of a hazard to public safety caused by Horizon Power electrical supply system, must:

Take immediate steps to protect the public

Seek assistance

Where possible, instruct a willing ordinary person to stand in a suitable position to warn public of the hazard, this instructed ordinary person must be willing to remain until the return of the authorised person, or until other assistance arrives.

Set up a NO-GO zone

Notify the control authority (HPCC)

In extreme emergencies that present an immediate threat to life, property or the environment:

Undertaking Emergency Switching to remove the threat can only be performed by an authorised person

Any emergency switching must be reported to the Control Authority (HPCC) as soon as the switching has taken place

De-energisation is mandatory if emergency services have to attend the hazard.

All electrical apparatus must be treated as LIVE unless proven otherwise.



3.4 Hazard Identification and Risk Assessment and Reporting

3.4.1 Hazards shall be identified and the associated risks assessed and controlled prior to working on or near any electrical apparatus.

3.4.2 Factors that assist in the control of hazards include:

Adhering to the Safe Approach Distances (SAD)

The work method employed, including the use of safety observers

The skill of knowledge of work team or individual

Adequate and effective communication

3.4.3 The risk assessment process shall be regularly audited to ensure compliance

All electrical apparatus shall be treated as LIVE unless proved otherwise.

3.5 Reporting Of Electrical Incidents

3.5.1 All electrical incidents where there is an electrical discharge, which has or could have caused injury or damage to property shall be reported to the ‘person in charge’ and Horizon Power, as soon as practicable.

3.6 First Aid

3.6.1 In the event of injury, any Horizon Power worker who undertake work in operational areas must be trained in First Aid and appropriate first aid kits shall be readily available for use at all worksites.

3.7 Elevated Work Platforms

3.7.1 All elevated work platforms (EWP) used near live electrical apparatus must be insulated to a voltage equal to or greater than the operating voltage of the apparatus being worked on.

3.8 Tools and Equipment

3.8.1 Only Horizon Power approved tools and equipment shall be used unless otherwise authorised as part of approved development.

3.8.2 Any defects or hazards with tools or equipment shall be tagged out of service, segregated from further use, and reported to the ‘person in charge’ as soon as possible.

3.8.3 Tools and equipment shall be periodically inspected and / or tested to ensure their safety for use.



3.9 Ladders and Scaffold

3.9.1 Ladders and scaffold used when working on or near live electrical apparatus shall be approved for electrical work.

3.9.2 Ladders and scaffold accessible to the public shall not be left unattended in the working position.

3.9.3 Ladders and scaffold shall be periodically inspected and / or tested to ensure their safety for use.

3.10 Personal Protective Equipment

3.10.1 All Horizon Power workers who work on or near Horizon Power‘s electrical network shall wear approved personal protective equipment (PPE).

3.10.2 Approved personal protective equipment (PPE) specified for the task or work area shall be worn.

3.10.3 Before undertaking any work each person shall check and ensure that all PPE is in good order and appropriate for the task or work being undertaken.

3.10.4 All defective PPE must be removed from use / service.

3.11 Permission to Work

3.11.1 A work permit shall be issued before approved work starts on or near any electrical apparatus.

3.11.2 A person working under the authority of a work permit shall be responsible to carry out that work under the conditions contained in the work permit.

3.11.3 The person shall also be satisfied that the required safety precautions have been taken.

3.11.4 Each section of the Work Permit shall be filled out by the relevant person determined in the Work Permit.

3.11.5 A person who permanently leaves the work site shall sign off the work permit.

3.11.6 A person who temporarily leaves the work site shall sign off the work permit and on return before starting work check with the Recipient in Charge (RIC) that the conditions of the work permit have not changed before re-signing on the work permit.



3.12 Handover Certificates

3.12.1 All work permits issued for electrical apparatus shall be cancelled before the electrical apparatus is handed over from one Operating Authority to another.

3.12.2 All persons working on electrical apparatus at the time of handover shall sign on the Handover Certificate.

3.12.3 This is to acknowledge that they understand the change in responsibility for control of that electrical apparatus.

3.12.4 On completion of the handover to the Operating Authority, the electrical apparatus may be connected to Horizon Power’s electrical system and energised.

3.12.5 A Handover Certificate from the Operating Authority to the Construction Authority shall be used to retire or take electrical apparatus out of service.

3.13 Safety Observers

3.13.1 The function of a Safety Observer, when appointed, shall be to warn all persons on that work site against unsafe approach to live electrical apparatus or other unsafe conditions.

3.13.2 The Person in Charge shall specifically instruct any Safety Observer in his duties on each occasion he is posted.

3.13.3 Work must cease if the safety observer’s view of the work is impaired.

3.14 Entry to Substations

3.14.1 Only inducted and authorised persons shall enter substations, switchyards or relay / control rooms.

3.14.2 The Control Authority shall be informed when any person enters or departs from a Substation, switchyard or relay / control room, all entries need to be recorded in the onsite log book. This may not be required in the case of distribution Substations.

3.15 Commissioning testing apparatus and underground cables

The purpose of commissioning any new, repaired or maintained electrical network, systems apparatus, such as over headlines and underground cables, connected to Horizon Power HV, LV system, is to determine the electrical apparatus is fit for purpose and service and is capable of safe operation and function.

Electrical commissioning and recommissioning, maintenance and testing

proves that the equipment meets a specific performance criterion before it is

energised.

Testing plant prior to energisation mitigates the possibility of failure on

connection to the Horizon Power electrical assets, system.



Horizon Power workers and including Workers operating, servicing, and/ or maintaining (SPS) Standalone Power Systems electrical equipment (inclusive of all generating methodologies), undertaking work on any electrical installations must take all practicable steps to maintain their electrical assets, systems apparatus, overhead lines and underground cables in a configuration and condition to meet the requirements for safety and functional operation.

They should also establish and operate administrative systems, including records of checks undertaken, that provide periodic safety checks at reasonable intervals appropriate to the operating environment and operational risks.

The purpose is to:

Check workmanship

Check condition of new repaired electrical apparatus, including labelling accuracy

Ensure electrical apparatus is safe

Ensure correct operation of apparatus.

3.16 Documentation and Records

All measurements and tests required should be recorded and the documentation kept.

To enable the integrity of the electrical installation over a long period of time and its suitability, the following records should be maintained:

initial design calculations and decisions

results of commissioning tests

results of periodic inspections and measurements

drawings showing the earthing system layout including location and size of all earth conductors and electrodes, and the location of all grid connections

3.17 Commissioning program and safety compliance review

Commissioning of new electrical assets, systems apparatus, overhead lines and underground cables is essential as a validation step for the design and installation process and for the design inputs.

In most cases commissioning should measure the outputs of the electrical apparatus, overhead line and underground cables in terms of produced voltages and current distributions.

The commissioning should consider closely the key performance criteria identified in the hazard identification and treatment analysis phases.

Commissioning will determine the electrical apparatus, overhead lines and underground cables initial compliance and set a benchmark or baseline for ongoing supervision.



As it is not always possible to foresee all hazards at the design stage, commissioning testing should also determine the need for any localised secondary mitigation and any additional requirements.

The electrical Commissioning procedure normally consists of six core activities, in some instances, not all activities are required:

Visual inspection

Continuity testing

Earth resistivity testing

Earth potential rise(EPR) measurement

Current distribution measurement

DANGER

Commissioning new electrical equipment can be extremely hazardous. It is crucial to take all safety precautions at each step of the process.

Failure to take safety precautions when commissioning can result in serious injury to personnel and to the public. It may also cause significant damage to plant and disruption to the electrical network.

Commissioning practices for transmission equipment can be more detailed and complex than commissioning of equipment for connection to the HV / LV assets, system. However, in both cases, the same extreme care and vigilance to potential hazards must be exercised.

DANGER

Always check that transformers with two sets of high voltage (HV) bushings have had the dust covers removed and dead end plugs fitted if only one set of bushings is in use.

Note: Make sure that the HV screens at SPUDS transformers are connected together in a common lug and bolted solidly at the earth bar.

Note: Fit a “Do Not Operate” danger tag to a cable where it is terminated at one end only (at the point of supply) and does not need to be energised.



3.18 Safety rules for testing and / or commissioning electrical apparatus

Minimum Requirements

Approved and appropriate PPE must be worn when carrying out testing and commissioning

The issuing officer of the STT has a duty to ensure that the condition of the equipment covered by the permit is safe for the proposed work to be undertaken.

Upon receiving the STT, the TIC has a duty to avoid danger during testing by:

Undertaking a risk assessment

Identifying the appropriate control measures implemented

Ensuring electrical apparatus and test equipment, leads and connections, are adequately guarded to prevent danger

Limited accessibility to the electrical apparatus for authorised persons and members of the public.

Posting relevant signs in obvious positions(throughout the entire period that the electrical apparatus may be subject to voltage

Ensuring all cables and capacitators are discharged before and after application of test voltage

Ensuring effective communication within the work party.

The risk assessment must take proper account of:

The types of test being carried out

The isolation of the electrical apparatus being tested.



3.19 Energising Electrical Apparatus

3.19.1 Before energising electrical apparatus the Person in Charge of the work shall ensure that all persons and relevant equipment are clear of that electrical apparatus, and it is safe to do so.

3.20 Work on Other Authorities’ Apparatus

Occasionally Horizon Power workers are required to operate and to work on or near electrical systems and associated plant / apparatus that are not owned or controlled by Horizon Power.

Prior to starting any such work there must be a clear agreement of the rules, documents and procedures that are used by all working parties.

All staff must be informed.

In the event that rules / policies are provided by a third party, these rules must be confirmed to at least comply with the ESS, the ESS is always the minimum standard.

In the case where no external –party rules, documents or procedures apply, Horizon Power’s ESS and related documents must be used.

4 GENERAL SWITCHING REQUIREMENTS

Apart from the emergency expectations, appropriately authorised, trained and competent switching operators and / or controllers within their limits of their authorised instructions can only perform switching operations.

4.1 High Voltage Switching and Earthing

4.1.1.1 Switching shall only be carried out by Authorised Switching Operators and within the limits of the switching authority issued.

4.1.1.2 For work continuing for any length of time, before work commences each day the Person in Charge shall inspect earthing equipment to make sure the earthing equipment in use is still correctly installed.

4.2 Operating Authority

All HV switching is coordinated through the Operating Authority Control Centre of Horizon Power (HPCC)

Transmission switching is controlled by HPCC

Generation switching is controlled by Generation Support Desk (GSD)

4.3 Switching Schedules (Program)

A switching schedule (switching program) is a sequential, numbered list of precisely ordered switching operations steps. A Distribution Network Access Request (DNAR) request must be submitted to generate a switching schedule for planned work.



4.4 Switching

At each item of the switching schedule, and before performing an operation, the switching operator and/or controller must verify:

The correct item number on the schedule

The correct location

The correct apparatus

The apparatus is in the expected state prior to operation and is fit to be operated.

Following the STOP, THINK, CHECK protocol is mandatory.

As a safety precaution the switching operator must give preference to operating to energise or de-energise equipment from a distance, or via a remote means.

Where available, voltage and current indicators must be used by the controller and/or switching operator to confirm switching and the apparatus operational status.

4.5 Fault Switching

Switching on Horizon Power’s network can only be carried out by persons appropriately authorised, trained and competent for the work they intend to do.

During fault conditions and during Fault Finding, additional hazards may be encountered, hazards such as:

System faults have many causes and can create different results, faults can range from high impedance down to low impedance faults, refer to Field Instruction 8.22 Switching Activities http://dm.horizonpower.com.au/otcs/llisapi.dll/properties/3331612

4.6 Isolations under fault conditions

HV / LV isolations are just as important when working under fault conditions as they are when working completing maintenance works

Equipment / apparatus must be isolated correctly and access permits must be issued before approaching equipment / apparatus.

Switching Programs must still be used, even if switching program is hand written (Emergency Fault Switching Program) in consultation with HPCC.

Re-energising the system with a fault still present, can cause serious problems; injury to personnel, public, livestock and damage to equipment.

Horizon Power workers that are required to replace fuses on the HV / LV overhead and underground network after a fault has occurred must ensure:

No attempt should be made to re-energise the line / cable without confirming as to the cause of the fault

Before replacing any fuses on the HV / LV overhead network after a fault and a blown fuse has occurred, a full line patrol will be conducted to ensure the fault has been cleared and the overhead line has been made safe.

http://dm.horizonpower.com.au/otcs/llisapi.dll/properties/3331612



The intention of an initial patrol before energisation shall be to ensure that the line is not hazardous to the public, livestock and equipment and to locate any obvious cause of the fault.

If the cause of the fault cannot be determined, call formal leader and /or HPCC and start detailed fault finding.

If the equipment, site location / environment is too hazardous, leave area de-energised and notify HPCC, formal leader and customer of hazardous situation.

Horizon Power employees and contractors that are required to replace fuses on the HV/LV overhead network after a fault has occurred must ensure (in consultation with HPCC):

No attempt should be made to re-energise the fused line, without

considering the possible cause of the fault, and without direction from

HPCC.

Before replacing any fuses on the HV/LV network after a fault (blown

fuse/s) has occurred a line patrol shall be conducted as far as is

practicable to ensure all reasonable attempts have been made to ensure

the safety of the public and the integrity of the line;

o The intention of a patrol before energisation shall be to ensure that the

line is not hazardous to the public, livestock and equipment and to

locate any obvious cause of the fault, therefore if all reasonable

attempts to patrol the line have been made and it has been determined

through a documented risk analysis those areas not accessible to

patrol are also inaccessible to other vehicles and pedestrians, an

attempt can be made to re-energise then line.

o Line Patrol on overhead LV faults shall be mandatory.

o Line Patrol on overhead HV within town boundaries shall be

mandatory.

If the re-energisation is successful then a full line patrol shall be conducted at the earliest practical time.

Following a line patrol which has not been able to identify the cause of a fault, an attempt can be made to re-energise the line to determine if the fault is transient or permanent.

This does not apply to outages during the Extreme or Catastrophic bushfire risk days (refer to Field Instruction 2.4 Fire Precautions for Field Work) where a full patrol must be conducted, before the line is energised.

If the cause of a permanent fault cannot be determined, call for help (formal leader and /or HPCC) and start detailed fault finding.

If the equipment, site location/environment is too hazardous or inaccessible, leave the area de-energised and notify HPCC, formal leader and customer of hazardous situation.



Underground HV/LV faults

Replacing fuses on the underground system, asset after a fault has occurred, it cannot always be determined if it was an overload or a permanent fault due to the inability of being able to test LV circuits with customers still connected.

Horizon Power employees and contractors that are required to replace fuses on the HV/LV underground system, asset after a fault has occurred must ensure:

LV circuit and path of the circuit will be identified and patrolled to ensure no fresh

excavations, fencing, or obvious incidents/accidents have occurred on that

circuit, then if nothing is found it will be acceptable whilst wearing all mandatory

PPE to attempt a fuse replacement, in consultation with HPCC.

If the fuse blows after one attempt, detailed fault finding on the circuit should be

undertaken to determine the cause, (a safety observer should be considered

during complex fault finding process).

On a concentrated HV underground network, the faulted area should be

determined by the use of fault indicators in RMU’s where available, to isolate the

faulted area prior to attempting a manual reclose.

If fault indicators are not available fault finding shall be undertaken in

collaboration with the HPCC to identify the faulted area.

STOP … THINK: What are the existing conditions?

CHECK: Are there other checks to be made before operation?

E.G. Permit status, earths to be applied and or removed and circuit breaker status.



4.7 Best Practice of Switching

Switching can only be carried out by a switching operator within the limits of the switching operator’s authorisation.

Switching is a highly technical and demanding task.

Potential errors are minimised by applying the STOP, THINK, CHECK rule prior to the start of each operation.

The operator must take precautions using the protocol – what are the existing conditions?

4.8 PAUSE: What has to be done?

Are you at the correct sequence on the switching programme? Check

Operations performed in the sequence of the switching programme. Check

Are you at the correct location? Check

Are you at the correct switch? Check the asset ID number

What operation has to be carried out? Check



4.9 PAUSE: Now check existing conditions.

Are there any other Checks to be made before operation, for example: permit status, earths removed and circuit breaker status?

Is the switch in the correct position? Check for example; if you have to turn the switch off, is it on?

Are there meters to indicate circuit conditions? Check if so, use them before and after?

Are there any tests that have to be made before operations? Check for example, Modiewark.

When returning from a break, the switching operator must confirm with the Operating Authority (HPCC) that they are still working from the correct schedule / program version and are at the right step.

4.10 Electrical Hazards

Electrical hazards pose a significant threat to the safety and health of employees, contractors and the general public.

Some common sources of electrical hazard include:

Inadvertent contact with live equipment

Unauthorised work within the danger zone

Faults, breakdown in insulation systems and equipment defects

Effects of direct and indirect lighting storms

Equipment becoming inadvertently live due to induced voltages or interference.

4.11 Shock

Shock is the unwanted flow of electricity through the body, typically occurs when the human body creates a path between a live apparatus and an earth. Electrical shock can cause severe electrical burns, internal tissue damage and /or ventricular fibrillation. Shock can stop the human heart on impact and can cause death. Small charges and induction from stray earths must not be underestimated.

The let go threshold is generally considered to be 10 mA, for a typical person this is equivalent to 10 volts.

Electric shock hazards can occur through step and touch in the vicinity of faulty electrical apparatus.



4.12 Arc Flash

An arc flash is the heat and light energy released when an insulator fails and current flows through a normally nonconductive media such as air.

The flash produced due to this breakdown is similar to the light radiation emitted by a commercial electrical arc welder.

The heat that is released may cause severe burns, especially to unprotected flesh and eyes.

4.13 Blast

A blast is an arc flash that yields an explosion and a massive amount of energy that rapidly vaporises metal conductors, blasting molten metal and superheated material called plasma in an outward direction with extreme force, the violent event can cause destruction of switchgear, and nearby equipment.

The high velocities of molten metal partials can cause severe burns, blindness, internal organ damage and death through inhalation.



4.14 Step Potential

Electricity always seeks the shortest and most direct conductive path to earth, in the case of a ground fault, for example fallen conductor, electricity will pass into the ground and fan outwards in a radial pattern with diminishing voltages.

Step potential is a shock hazard that occurs when a person is close or steps towards the energised contact site.

The step voltage that passes through the body is calculated by the difference in voltage of the energised soil between their feet.

Fig 1: Step Potential – 22 k V System

In figure 1, fault current is travelling down a conductor to the ground, the conductor is energising the ground and the voltage fans outwards in a radial pattern diminishing in voltage as it moves from the contact site. Standing with one foot in the 8 k V voltage zone Which is determined by the distance from contact point on the ground, and a second foot within the 6 k V voltage zone, this person would experience a hazardous shock of 2 k V (2000 volts)



4.15 Touch Potential

Touch Potential is when contact is made though an energised object. The touch voltage that passes through the body is equal to the difference between the voltage of the energised object and the voltage of the zone where the feet are placed, remembering that voltages diminish in an outward radial pattern from the contact site.

Fig 2: Touch Potential – 22 k V System

In Figure 2, touching the 12.7 k V conductor while standing within the 10 k V voltage zone which is determined by the distance from contact site would yield a hazardous shock of 2.7 k V (2,700 volts)

4.16 Electrical Apparatus Labels

Electrical apparatus such as circuit breakers, isolators, dis-connectors, fuses or other method of making or breaking and electrical circuit must be clearly labelled by an approved means, this is to ensure that all electrical apparatus can be accurately identified and described.

All electrical apparatus must be legibly and permanently labelled to clearly identify the equipment.

Where applicable a label should also identify what an apparatus is connected to, and portion of the electrical installation that it covers.

Destination labels must be proved prior to equipment being handed over for connection.



5 SYSTEM ACCESS TAGS

Only System Access Tags approved by Horizon Power are permitted for use, metal tags must not to be used under any circumstances.

Changing the purpose, colour and / or wording of a tag is prohibited without the approval of the Operating Authority (HPCC)

When applying electrical tags, the correct electrical tag must be used for the type of work been carried out.

Tags associated with a work permit and /or JRA must be recorded on the corresponding work permit and / or JRA.

Locks

Isolate/Barrier and Tag out

The Network Permit to Work Standard (NPTW) does not use any procedures that incorporate personal locks on isolation points.

As part of the normal NPTW isolation procedure, the Switching Operator shall use a Horizon Power lock on a point of isolation if that apparatus has a locking facility.

For more information regarding Network Tags refer to: Networks Permit to Work Training Manual http://dm.horizonpower.com.au/otcs/llisapi.dll/properties/4920830




6 ISOLATION OF ELECTRICAL APPARATUS

The purpose of isolation is to safely disconnect electrical apparatus from all possible sources of supply, isolation points must be rendered incapable of being energised unintentionally.

Where locking facilities are available it must be used to lock the electrical apparatus in the off position (check POFF) and a danger tag fitted.

If barriers are required to prevent unsafe access to live parts, only approved Horizon Power barriers can be used.

7 EARTHING / SHORT CIRCUITING (BOXED IN)

The purpose of earthing / short circuiting is to:

Limit the rise of potential difference in the work area and trigger the protection equipment to disconnect supply if supply is inadvertently restored.

Safely discharge induced and residual voltages.

Safely discharge electrical charges caused by lightning, wind, changes in ambient conditions or altitude.

Before electrical apparatus is earthed / short circuited, it must be tested for de-energised with an approved in current test date instrument.

The de-energised test is preformed using the following sequence:

The instrument is proved to be working

The instrument is used to prove the circuit under test is de-energised

The instrument is proved to be working.

Earths must be applied immediately after the tests have proven de-energised; this process must be repeated at all earthing points (All points of supply must be protected under a set of earths/shorts, Boxed In)

When placing earth leads, the connection to the main earth must be made first and removed last.

7.1 Program Earths

Program earths must be applied to protect the work site against inadvertent energisation from all possible sources of supply. The work site is the area within the isolation points and between the program earths.

The switching officer is responsible for the application of program earths, the switching officer cannot delegate this responsibility but may directly and continually supervise another authorised person required to perform this task.

The removal of program earths under a switching program, immediately following the cancellation of an EAP, must be signed-off on the EAP in the “Removed By” column, this serves as an additional safety precaution and double-check that all program earths have been removed.



Permission must be granted by the Control Authority (HPCC) before program earths can be placed in locations that are different to those written on the switching program.

7.2 Working Earths (Boxed in)

Working earths are used to ensure earths are covering all sources of supply. A working earth is not required when program earths are visible from both sides of the work site.

The Recipient in Charge (RIC) is accountable for the application and removal of working earths, Recipients must not apply working earths without the approval of the RIC, all working fitted or removed must be noted on the work permit

Working earths should be installed as close as possible to either side of the work being carried out. (Box yourself in)

7.3 Earthing / Shorting Equipment Check

Prior to commencing or recommencing work, the RIC must inspect the earthing / shorting equipment in use to make sure it is still correctly installed, particularly those installed on previous days.

All earths and shorting equipment shall be inspected prior to use.

All earths and shorting equipment shall be within its current test period and tagged

7.4 Electromagnetic Induction

Working earths can also be used to control induced and static voltages at the work site.

In situations where it is considered that the program earths do not provide adequate protection from electromagnetic induction, additional working earths/ shorts must be used.

Due regard is to be given to conductor earthing on power lines under construction for both connectable and non-connectable to the network, due to the risk of electromagnetic induction, static induction and lightning.



8 WORK PERMITS

All work permits are designed for the safety of all personnel and the electrical apparatus. The appropriate work permit is used to grant access for work on or near Horizon Power’s Transmission and Distribution electrical apparatus.

The three work permits associated with the Horizon Power Permit to Work are the:

Electrical Access Permit (EAP)

Vicinity Authority (VA)

Sanction to Test (STT).

All Horizon Power workers deemed to be an Authorised Persons must understand each work permit’s specific application, who is authorised to work with that permit, and the standard procedure and variations to the standard procedure associated with each permit.

A fourth work permit and its associated procedures are pending, and the subject of further development. The proposed work permit is the Access to Live Electrical Apparatus (ALEA) work permit. This permit will be used for work on energised electrical apparatus.

8.1 Dead Access/Isolate, De-Energised, Proved De-Energised and Earthed

8.1.1 Electrical apparatus shall be made dead.

8.1.2 The Recipient in Charge shall advise all Recipients of the isolation and program earth locations.

8.1.3 The Recipient in Charge may remove or install working earth’s and shall advise all Recipients.

8.1.4 Multiple Permits may exist on single electrical apparatus, refer to Switching Operators Manual- Distribution (http://dm.horizonpower.com.au/otcs/llisapi.dll?func=ll&objaction=overview&objid=5011675)

8.1.5 Program Earths may be temporarily removed during work ONLY for the purpose of testing and only after:

a) All persons working under the work permit are notified;

b) The Issuing Officer has granted permission.

8.1.6 Work shall not restart until the test is complete and earths reapplied.

http://dm.horizonpower.com.au/otcs/llisapi.dll?func=ll&objaction=overview&objid=5011675

http://dm.horizonpower.com.au/otcs/llisapi.dll?func=ll&objaction=overview&objid=5011675



8.2 Vicinity or Live Access

8.2.1 The Recipient in Charge shall advise all persons of the live electrical apparatus and safe approach distance (SAD).

8.2.2 Multiple work permits may exist on single electrical apparatus.

8.3 Testing

8.3.1 The Tester in Charge shall advise all Recipients of the points of isolation, safe work area, live electrical apparatus and safe approach distance.

8.3.2 Multiple work permits cannot exist on single electrical apparatus.

8.3.3 A work permit to test may be issued for work on the control and protection circuits of a primary electrical apparatus even though a separate work permit has been issued for primary access. Adequate secondary isolations shall be made.

8.3.4 The Tester in Charge may remove or install working earths and shall advise all Recipients.

The Tester in Charge may energise any electrical apparatus for the purpose of testing, provided all persons of the work party have been notified beforehand.



8.4 Electrical Apparatus Declared Out of Use

8.4.1 The Control Authority may declare electrical apparatus out of use by removing from each source of electrical supply a permanent length of conductor.

For High Voltage the length of conductor permanently removed shall be at least equal to the minimum safe approach distance for the voltage to be worked on.

For Low Voltage a permanent length of conductor must be removed with a minimum gap of 150 mm.

Note: Fuses, Links, Live line Taps, Switches or Isolators shall not be regarded as a permanent length of conductor.

Note: Removal of taps is not considered “declared out of use”

8.4.2 Electrical apparatus declared out of use may be accessed without a work permit.

Even though electrical apparatus is declared out of use, the risk assessment process must consider the possibility of induction, lightning strikes, static charges, PV back feed etc.

Personal earths / shorts must be applied.

9 APPROACH TO ELECTRICAL APPARATUS

‘The closer the apparatus, the greater the hazard’

A hazard is impacted by the following:

Skills and / or qualifications of the person(s) working on or near the electrical apparatus

Supervision of the work party and environment

Type of work activity being performed.

9.1 Danger Zone

A danger zone is a specific area surrounding live electrical apparatus that ordinary persons, equipment and materials must not enter. The area of the danger zone is determined by the voltage of the electrical apparatus.

Reference to the Occupational Safety and Health Regulations 1996 reg 3.64, a danger zone means anywhere that:

is within 0.5 meters of a live insulated overhead power line or aerial bundled conductor line of a voltage of not more than 1,000 volts;

is within 1.0 meter of a live uninsulated overhead power line of a voltage of not more than 1,000 volts;

is within 3.0 meters of a live overhead power line whether insulated or not, of a voltage exceeding 1,000 volts but not more than 33, 000 volts; or



Is within 6.0 meters of a live overhead power line whether insulated or not, of a voltage exceeding 33,000 volts.

9.2 Safe Approach Distance (SAD)

Safe Approach Distance (SAD) is the distance an authorised person, vehicle, mobile plant including its load, controlling ropes and any other accessories or object, other than insulated objects designed for contact with live conductors must maintain when;

Working in the vicinity of electrical apparatus

Operating vehicles or mobile plant in the vicinity of electrical apparatus.

Authorised persons may enter the danger zone; however they must not enter the SAD zone.

Only specially trained live line authorised personnel may enter the SAD while following live line procedures.

Workers shall observe an appropriate safe approach distance when working, or operating vehicles or mobile plant, near electrical apparatus.

Work in the vicinity of any electrical apparatus shall be carried out in a safe manner and control measures taken shall be consistent with the risk and work performed.

The SAD’s in these Electrical Safety Standards are based on an ‘exclusion zone’ principle

This defines an area around the electrical apparatus into which no part of the worker, mobile plant or object other than approved insulated objects.

When working at these distances work practices shall be established to ensure workers, mobile plant and unapproved objects do not encroach on the SAD’s.

Refer to Fig 3: – Safe approach distance to exposed live conductors for ordinary persons, instructed persons and authorised workers.

Refer to Fig 4: – Safe approach distance to exposed live conductors for vehicles and mobile plant.

Unnecessary approach to live exposed electrical apparatus shall be avoided.



Figure: 3



Figure: 4



9.3 Authorised Persons

For network access, “authorised persons” include Issuing Offices, RIC’s, TIC’s and Recipients.

For other electrical, non-electrical access work, “authorised persons” includes those with electrical licence, ensuring regulatory or other relevant authority requirements are met

9.4 Safe Approach Distance (SAD)

Ordinary persons cannot enter a worksite or sign onto a permit unless under direct supervision of an authorised person.

If ordinary persons are working, they must have an authorised RIC on site and been directly supervised when undertaking work inside the Danger Zone, refer to Field Instruction 2.17 Safe Approach Distance http://dm.horizonpower.com.au/otcs/llisapi.dll/properties/2225533




10 HIGH VOLTAGE

10.1 General

10.1.1 The description and location of the electrical apparatus to be worked on and the safety measures to be taken shall be clearly understood by all persons intending to work on that electrical apparatus.

10.1.2 A person shall not touch any insulator that is in direct contact with a Live Conductor. Insulators are defined as Pin, Disc strings, Post and Polymer types.

Note: This does not apply to Authorised HV Live glove and barrier work.

10.2 Remote or Automatically Controlled Electrical Apparatus

10.2.1 Prior to the issue of a work permit to work on or near live electrical apparatus, the remote or automatic function shall be made inoperative.

10.3 Approach to Cables

10.3.1 Cables energised at high voltage shall not be moved unless permission has first been given by the Control Authority, and then only under direct instruction from an authorised person.

10.3.2 No work shall commence on accessing conductors of high voltage cables until after:

All appropriate identification and spiking procedures have been carried out (spiking does not apply to terminations) and

A work permit has been issued.

10.4 Live High Voltage Work

10.4.1 Live high voltage work shall only be carried out by authorised and competent persons and in accordance with the provisions of the HV Live Work Manual.

10.4.2 Permission to work shall be in the form of a work permit.

10.4.3 Placing Earths (Boxed In)

10.4.3.1 Prior to installing earths persons shall make sure approved tests have been completed to confirm that the electrical apparatus is De-energised.

10.4.3.2 Where a permanently installed earth point is available it shall be used.

10.4.3.3 Where there is no installed earth point an approved metal earthing stake shall be driven into the ground. Care shall be taken to avoid driving this stake into



other underground services such as Power cables, Water pipes, Telephone cables etc.

10.4.3.4 When placing earth leads the connection at the earth point shall be made first and all persons should keep clear of the earth leads.

10.4.3.5 When removing earth leads the connection at the earth point shall be removed last.

10.4.3.6 The neutral conductor of the low voltage system shall not be used as a high voltage earth.

10.4.4 Location of Earths (Boxed In)

10.4.4.1 Earths shall be placed on all sides of the work site, (Boxed In at all times)

10.4.4.2 Earths should be placed so as to remain effective even if the electrical apparatus covered by the work permit is disconnected.

10.4.5 Capacitors and Cables

10.4.5.1 Before any person touches de-energised Capacitors, all conductors, including neutral conductors shall be discharged and earthed.

10.4.5.2 The same precautions shall be taken with Capacitors, which are part of any electrical apparatus.

10.4.5.3 Before any person touches de-energised cables, all conductors, including screen conductors shall be discharged and earthed.

10.4.6 Induced Voltages (Induction)

10.4.6.1 Where it is considered necessary to protect from induced voltages, additional earthing equipment shall be used.

10.4.6.2 The Recipient in Charge is responsible to make sure all additional earthing equipment is recorded on the work permit.

10.4.7 Locking (Isolate, Barrier and Tag Out)

10.4.7.1 Where earthing points have locking facilities, they shall be used.

10.5 Dead High Voltage Work

10.5.1 General

10.5.1.1 High Voltage electrical apparatus shall be isolated from all sources of supply.

10.5.1.2 The electrical apparatus shall be proved De-energised by performing the approved test or tests.

10.5.1.3 The electrical apparatus shall be earthed by approved methods.

10.5.1.4 Approved danger or other labels shall be fitted and where practical, approved barriers and/or ropes shall be erected.



10.5.2 Work On Dead High Voltage

10.5.2.1 No person shall access any High Voltage electrical apparatus until:

They have signed onto a work permit; or

The electrical apparatus has been declared out of use.

10.5.3 Double Circuit Lines

10.5.3.1 Where work is carried out on a High Voltage double circuit line, the electrical apparatus to be worked on shall be clearly and continuously identified in the approved manner to all persons covered by the work permit.






11 LOW VOLTAGE

11.1 General

11.1.1 The description and location of the Low Voltage electrical apparatus to be worked on and the safety measures to be taken shall be clearly understood by all workers intending to work on that electrical apparatus.

11.1.2 The Person in Charge shall give adequate instruction to competent persons before work commences on or near Low Voltage electrical apparatus.

11.2 Live Low Voltage Work

11.2.1 Only competent persons using approved work methods shall carry out work on uninsulated live Low Voltage electrical apparatus.

11.2.2 Do not allow different parts of the body to make contact with separate uninsulated live Low Voltage electrical apparatus and conducting surfaces of different voltages at the same time.

11.2.3 Approved insulating gloves with outer protection must be worn when working on live Low Voltage electrical apparatus or de-energised Low Voltage work within reach.

11.2.4 Tools used for work on any live Low Voltage electrical apparatus shall be approved for the task concerned.

11.2.5 Approved safety equipment shall be used to prevent inadvertent contact with live Low Voltage electrical apparatus.

11.2.6 When handling any tools or equipment, care shall be taken to avoid contact with adjacent live Low Voltage electrical apparatus and conducting surfaces of different potential / voltages at the same time.

11.2.7 Approved insulating covers shall be used to prevent inadvertent contact with live Low Voltage electrical apparatus or conducting surfaces of different potential / voltages except where approved methods permit otherwise.

11.2.8 A competent Safety Observer shall be present when work is being carried out on live Low Voltage electrical apparatus except for the following tasks:

Testing, removal and installation of meters

Inspection and replacement of fuses

Maintenance of control circuits



11.2.9 De-Energised / Isolated Low Voltage Work

11.2.10 Low voltage electrical apparatus must be Isolated in such a way the circuit cannot be inadvertently energised.

11.2.11 Where the Low Voltage electrical apparatus cannot be isolated, de-energised and earthed or LV shorts fitted, then the electrical apparatus shall be treated as LIVE.

11.3 Dead Low Voltage Work

11.3.1 General

11.3.2 Low Voltage electrical apparatus shall be Isolated from all sources of supply.

11.3.3 The Low Voltage electrical apparatus shall be proved de energised by an approved test.

11.3.4 Low Voltage overhead and underground electrical apparatus shall be short-circuited where practicable using approved equipment.

11.3.5 All control and isolation points shall be danger labelled and barriered off or locked out except where a section of conductor etc. has been removed to create an isolation point. At these isolation points a danger label will only be required.

11.3.6 Work On Dead Low Voltage

11.3.7 No person shall commence work on any isolated, de-energised and earthed Low Voltage electrical apparatus until:

They have signed onto a work permit

The Low Voltage electrical apparatus has been declared Out of Use.

Western Power Plain Document...These Electrical Safety Standards provide the minimum electrical safety principals for activities related to construction, testing, commissioning, operation

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