Working Overhead Underground Electric Lines

Working in the Vicinity of Overhead and

Underground Electric Lines

Draft

Code of Practice

SAFE WORK AUSTRALIA MEMBERS’ MEETING 6

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Table of Contents

FOREWORD.................................................................................................................................4

SCOPE AND APPLICATION........................................................................................................4

1. INTRODUCTION...................................................................................................................61.1 What is working in the vicinity of overhead and underground electrical services?........61.2 Who has the health and safety duties?..........................................................................61.3 What is involved in managing electrical risks?...............................................................61.4 Planning and preparation before starting work..............................................................7

2. APPROACH DISTANCES – OVERHEAD ELECTRIC LINES.............................................92.1 Approach Distances.......................................................................................................92.2 Unauthorised Person Zone..........................................................................................122.3 Authorised Person Zone..............................................................................................122.4 No Go Zone – Approval of the electricity supply authority...........................................132.5 Approach Distances for Vehicles.................................................................................142.6 Authorised Person.......................................................................................................152.7 Safety Observer...........................................................................................................15

3. OPERATING CRANES AND MOBILE PLANT – OVERHEAD ELECTRIC LINES...........173.1 Identify hazards............................................................................................................173.2 Assess risks.................................................................................................................183.3 Control risks.................................................................................................................183.4 Workers in contact with the crane, load or mobile plant..............................................223.5 Work in the Safety Observer Zone...............................................................................233.6 Work in the Authorised Person Zone...........................................................................243.7 Cranes and mobile plant..............................................................................................25

4. TREE AND VEGETATION MANAGEMENT – OVERHEAD ELECTRIC LINES................264.1 Managing risks.............................................................................................................264.2 Identify hazards............................................................................................................284.3 Assess risks.................................................................................................................284.4 Control risks.................................................................................................................294.5 Trees or branches contacting energised overhead electric lines.................................30

5. SCAFFOLDING WORK – OVERHEAD ELECTRIC LINES...............................................315.1 Identify hazards............................................................................................................315.2 Assess risks.................................................................................................................315.3 Control risks.................................................................................................................315.4 Specific control measures............................................................................................325.5 Erected scaffolding – use of a hoarding and enclosure for reduced safety clearances34

6. AGRICULTURAL WORK – OVERHEAD ELECTRIC LINES.............................................366.1 Identify hazards............................................................................................................366.2 Assess risks.................................................................................................................366.3 Control risks.................................................................................................................376.4 Particular circumstances..............................................................................................39

7. LOW VOLTAGE OVERHEAD ELECTRIC LINES NEAR BUILDINGS AND STRUCTURES....................................................................................................................40

7.1 Approach Distances.....................................................................................................417.2 Identify hazards............................................................................................................417.3 Assess risks.................................................................................................................427.4 Control risks.................................................................................................................42


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8. TRANSPORTATION OF HIGH LOADS – OVERHEAD ELECTRIC LINES.......................448.1 Meaning of specific terms used in transporting high loads..........................................448.2 Transport requirements for high load categories.........................................................458.3 Responsibilities – Electrical safety...............................................................................46

9. ELECTRICAL RISKS UNDERGROUND AND IN BUILDINGS..........................................489.1 Identify hazards............................................................................................................489.2 Assess risks.................................................................................................................489.3 Control risks.................................................................................................................499.4 Notes on cable identification........................................................................................50

APPENDIX A – DEFINITIONS....................................................................................................52

APPENDIX B – CASE STUDIES - INCIDENTS AND SCENARIOS..........................................53

APPENDIX C – EMERGENCY RESCUE PROCEDURE............................................................56

APPENDIX D – REQUIREMENTS FOR THE TRANSPORTATION OF HIGH LOADS.............59

APPENDIX E – OTHER RELEVANT INFORMATION................................................................60


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FOREWORD

This Code of Practice on managing risks when working in the vicinity of overhead and underground electric lines is an approved code of practice under section 274 of the Work Health and Safety Act (the WHS Act).

An approved code of practice is a practical guide to achieving the standards of health, safety and welfare required under the WHS Act and the Work Health and Safety Regulations (the WHS Regulations).

A code of practice applies to anyone who has a duty of care in the circumstances described in the code. In most cases, following an approved code of practice would achieve compliance with the health and safety duties in the WHS Act, in relation to the subject matter of the code. Like regulations, codes of practice deal with particular issues and do not cover all hazards or risks which may arise. The health and safety duties require duty holders to consider all risks associated with work, not only those for which regulations and codes of practice exist.

Codes of practice are admissible in court proceedings under the WHS Act and Regulations. Courts may regard a code of practice as evidence of what is known about a hazard, risk or control and may rely on the code in determining what is reasonably practicable in the circumstances to which the code relates.

Compliance with the WHS Act and Regulations may be achieved by following another method, such as a technical or an industry standard, if it provides an equivalent or higher standard of work health and safety than the code.

An inspector may refer to an approved code of practice when issuing an improvement or prohibition notice.

This Code of Practice has been developed by Safe Work Australia as a model code of practice under the Council of Australian Governments’ Inter-Governmental Agreement for Regulatory and Operational Reform in Occupational Health and Safety for adoption by the Commonwealth, state and territory governments.

A draft of this Code of Practice was released for public consultation on 2 April 2012 and was endorsed by the Select Council on Workplace Relations on [to be completed].

SCOPE AND APPLICATION

This Code provides practical guidance for persons conducting a business or undertaking on how to ensure, so far as is reasonably practicable, that no person, plant or thing at the workplace comes within an unsafe distance of an overhead or underground electric line.

This Code should be read in conjunction with Code of Practice: Managing electrical risks in the workplace as it provides specific guidance on managing the risks associated with electrical safety and energised electrical work.

This Code does not apply to: works carried out by or on behalf of an electricity supply authority on the electrical

equipment, including electric line-associated equipment, controlled or operated by the authority to generate, transform, transmit or supply electricity

mobile plant or vehicles operating on a public road where the design envelope is not greater than the transit envelope and is in any case not greater than 4.6 metres in height (for example, a side loading waste collection vehicle collecting waste bins from the side of a public road under overhead electric lines)

a crane or item of plant correctly stowed for travelling on a public road, and


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work carried out by emergency services personnel, including state emergency services, fire, police, volunteer rescue associations and ambulance personnel during a declared emergency or other local emergency incident.

How to use this code of practice

In providing guidance, the word ‘should’ is used in this Code to indicate a recommended course of action, while ‘may’ is used to indicate an optional course of action.

This Code also includes various references to provisions of the WHS Act and Regulations to provide context with legal requirements. These references are not exhaustive. The words ‘must’, ‘requires’ or ‘mandatory’ indicate that these legal requirements exist, which must be complied with.


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1. INTRODUCTION

Electrical risks are risks of death, electric shock or other injury caused directly or indirectly by electricity. Contact with energised overhead or underground electric lines can be fatal, whether they are carrying a voltage as high as 400 000 V or as low as 230 V.

Actual contact with overhead electric lines is not necessary to result in electric shock. A close approach to the line conductors may allow a ‘flashover’ or arc to take place. The risk of flashover increases as the line voltage increases.

1.1 What is working in the vicinity of overhead and underground electric lines?Work ‘in the vicinity of’ overhead and underground electric lines means a situation where there is a reasonable possibility of a person, either directly or through any conducting medium, coming within an unsafe distance specified in this Code. For the purposes of this Code the term ‘in the vicinity of’ can be interchanged with other legislative or commonly used industry terms i.e. ‘close proximity’, ‘unsafe distance’ or ‘near’.

Other definitions of key terms used in this Code are at Appendix A.

1.2 Who has the health and safety duties?A person conducting a business or undertaking has the primary duty under the WHS Act to ensure, so far as is reasonably practicable, that workers and other persons are not exposed to health and safety risks arising from the business or undertaking.

A person conducting a business or undertaking has more specific duties under the WHS Regulations to manage electrical risks, including ensuring, so far as is reasonably practicable, that no person, plant or thing at the workplace comes within an unsafe distance of an overhead or underground electric line.

Designers, manufacturers, importers, suppliers or installers of plant or structures that could be used for work must ensure, so far as is reasonably practicable, that the plant or structure is without risks to health and safety. Designers and manufacturers of electrical equipment or installations must ensure they are designed and manufactured so that electrical risks are eliminated or, if this not reasonably practicable, minimised so far as is reasonably practicable.

Officers, such as company directors, have a duty to exercise due diligence to ensure that the business or undertaking complies with the WHS Act and Regulations. This includes taking reasonable steps to ensure that the business or undertaking has and uses appropriate resources and processes to eliminate or minimise risks to health and safety.

Workers have a duty to take reasonable care for their own health and safety and not adversely affect the health and safety of other persons. Workers must comply with any reasonable instruction and cooperate with any reasonable policy or procedure relating to health and safety at the workplace.

1.3 What is involved in managing electrical risks?

In order to manage risk under the WHS Regulations, a duty holder must:

identify reasonably foreseeable hazards that could give rise to the risk

eliminate the risk, so far as is reasonably practicable

if it is not reasonably practicable to eliminate the risk, minimise the risk so far as is reasonably practicable by implementing control measures


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maintain the implemented control measure so that it remains effective

review, and if necessary revise, all risk control measures so as to maintain, so far as is reasonably practicable, a work environment that is without risks to health and safety.

This Code provides guidance on how to manage electrical risks associated with working in the vicinity of overhead and underground electric lines by following a systematic process that involves:

identifying hazards

if necessary, assessing the risks associated with these hazards

implementing and maintaining risk control measures

reviewing risk control measures.

Electric lines should always be treated as live. Further guidance on managing electrical risks generally is available in the Code of Practice: Managing Electrical Risks in the Workplace.

Consulting your workers

Consultation involves sharing of information, giving workers a reasonable opportunity to express views and taking those views into account before making decisions on health and safety matters.

You must consult, so far as is reasonably practicable, with workers who carry out work for the business or undertaking and who are (or are likely to be) directly affected by a work health and safety matter. If the workers are represented by a health and safety representative, the consultation must involve that representative.

Consultation with workers and their health and safety representatives is required at every step of the risk management process. By drawing on the experience, knowledge and ideas of your workers you are more likely to identify all hazards and choose effective risk controls.

Consulting, co-operating and co-ordinating activities with other duty holders

You must, so far as is reasonably practicable, consult, co-operate and co-ordinate activities with all other persons who have a work health or safety duty in relation to the same matter.

Sometimes you may have responsibility for a health and safety matter along with other business operators who are involved in the same activities or who share the same workplace. In these situations, you should exchange information to find out who is doing what and work together in a co-operative and co-ordinated way so that all risks are eliminated or minimised so far as is reasonably practicable.

For example, if you hire a crane company to carry out lifting operations at your workplace and there are overhead electric lines, you should consult with the crane operator as well as with the electricity supply authority regarding safe approach distances and control measures to prevent contact. Duty holders should co-operate with each other and co-ordinate activities to ensure that workers are not exposed to electrical risks (e.g. instructing on and ensuring compliance with ‘no go’ zones’).

Further guidance on consultation is available in the Code of Practice: Work Health and Safety Consultation, Co-operation and Co-ordination.

1.4 Planning and preparation before starting workCareful planning and preparation is an essential step to ensure that work is done safely, this can include:


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identifying the nature of the work planned and ways of dealing with changes as the work proceeds

the possible hazards and risks associated with the work consultation with the electricity supply authority regarding the proposed work compliance with any conditions imposed by the electricity supply authority for the work an effective communication system in place to ensure communication and interaction

between workers at the site training, qualifications and competency of workers provision of information and instruction to operators and other workers about control

measures to eliminate or minimise electrical risks supervision to ensure safe work procedures are followed checking the operation of plant and equipment, including the operation of limiting devices proximity of persons, cranes, mobile plant, material and tools to overhead electric lines proximity of persons to cranes and mobile plant workplace access and egress emergency rescue procedures ensuring approach distances are appropriate for the authorisation levels of the workers

undertaking the work.

When preparing for the work, a person conducting business or undertaking should ensure no new hazards are created.

Safe work method statements

Construction work that is carried out on or near energised electrical installations or services is defined as ‘high risk construction work’.

A safe work method statement (SWMS) is required for energised electrical work, as well as any high risk construction work. The SWMS must be prepared before any work commences. Further guidance on developing a safe work method statement is provided in the Code of Practice: Construction Work.


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2. APPROACH DISTANCES – OVERHEAD ELECTRIC LINES

Regulation 166: A person conducting a business or undertaking must ensure, so far as is reasonably practicable, that no person, plant or thing at the workplace comes within an unsafe distance of an overhead electric line.

If this is not reasonably practicable, the person must ensure that a risk assessment is conducted in relation to the proposed work and control measures implemented are consistent with the risk assessment and, if an electricity supply authority is responsible for the electric line, any requirements of the authority.

This Section provides guidance on competency requirements and approach distances to energised electrical conductors, including no go zones for cranes and plant (and their loads), as well as for vehicles, individuals and hand-held tools. Approach distances apply to persons with varying levels of qualification, training or knowledge.

This Code is based on the assumption that without appropriate technical knowledge and experience of electricity distribution networks and associated electrical equipment, many persons working in the vicinity of overhead electric lines will not be able to identify the operating voltage, and will therefore not be able to recognise and avoid the inherent dangers of energised overhead electric lines. These persons are termed unauthorised persons.

2.1 Approach DistancesNote: Please refer to the draft model Work Health and Safety Codes of Practice Issues

Paper for further information on the issues associated with approach distances.

An approach distance is the minimum separation in air from an exposed overhead conductor that should be maintained by a person, or any object held by or in contact with that person. The approach distances specified take account of differing levels of technical knowledge and items of plant and are greater for unauthorised persons than for authorised persons who have been trained and assessed as having the necessary technical knowledge and skills.

The approach distances for unauthorised persons and authorised persons are based on those specified in the National Guidelines for Safe Approach Distances to Electrical Apparatus. These approach distances were derived by determining a distance to avoid electrical flashover and providing an additional allowance for inadvertent movement of the person, crane or mobile plant relative to the overhead electric lines, or the movement of the overhead electric lines relative to the person, crane or mobile plant.

The approach distances set out in this section are only part of an overall safe system of work, which should be implemented by any person conducting a business or undertaking working in the vicinity of overhead electric lines and associated electrical equipment.

Assessing the relevant approach distance

Before starting any work in the vicinity of overhead electric lines it is essential that the height and voltage of the overhead electric lines (and if applicable the horizontal safety clearance) be assessed at the worksite. When assessing the relevant approach distances for the work shown in Figure 1, a number of factors should be considered including:

the possibility of errors in estimating distances, especially at higher voltages, where the approach distance is large. It may be necessary either to allow more clearance or to use methods that provide more accurate estimation of distances, for example, an ultrasonic cable height indicator, which provides a safe and accurate method of estimating distances near overhead electric lines. If the height or voltage of the overhead electric lines cannot


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be accurately determined, you should consult the electricity supply authority in your state or territory.

Figure 1: Distance that should be assessed for each worksite.

overhead electric lines are made of metal and are therefore subject to expansion and contraction when heated and cooled. This can be a direct result of high ambient air temperature and/or excessive electrical load current passing through the conductors. Regardless of the cause, any expansion will result in gravity causing the electric lines to sag downwards. Wind can also cause the electric lines to swing from side to side. For this reason the approach distances should be increased either vertically or horizontally by the amount of conductor sag or swing at the point of work, shown in Figure 2.

Figure 2: Overhead electric line ‘sag or swing’.


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where more than one voltage is present, for example, overhead electric lines where two or more circuits operating at different voltages are supported on the same poles, the approach distance appropriate to each voltage should be maintained independently.

increased clearances should be allowed where a risk assessment identifies a reasonable possibility of the load or lifting gear (crane hook, chains and slings) moving or swinging towards the overhead electric lines or associated electrical equipment when the crane or item of mobile plant is operated.

A warning sign, shown below, can alert workers and others to possible hazards when estimating approach distances.

Increase to approach distances

Certain Australian Standards and industry practices require greater approach distances than those described in this Code. For certain types of work or classes of authorisation and competency, greater distances than that described in this Code may be appropriate. For example, the approach distances shown in Table 1 are less than those described in AS: 2550.5 Cranes, hoist and winches - Safe Use Part 5: Mobile cranes.

Local electricity supply authorities may also have more stringent requirements.

How close can I go to overhead electric lines?

Once an assessment has been carried out of the worksite and the overhead electric lines, a decision can be made on the approach distance for the proposed work. The approach distances and work zones described in this section and shown in Figure 3 vary with the voltage of the overhead electric lines and the level of authorisation of the person/s performing the work.

Figure 3: Approach distances and work zones in the vicinity of overhead electric lines.


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The relevant approach distances are set out in the following tables1:

Table 1 provides approach distances for unauthorised persons. These are workers who have not received training in overhead line electrical hazards and do not have sufficient training or experience to enable them to avoid the dangers which overhead electric lines and associated electrical equipment may create. Unauthorised workers are restricted to work in the unauthorised person zone (see Section 2.2 and Figure 3).

Table 2 provides reduced approach distances for authorised persons. These are workers who have successfully completed a recognised training course in overhead line electrical hazards and are therefore permitted to work closer to the overhead electric lines in the authorised person zone (see Section 2.3 and Figure 3).

Table 3 provides approach distances for vehicles that are driven under overhead electric lines (see Section 2.5 and Figure 4).

Approach distances can vary depending on the voltage and apply to: any part of a crane or item of mobile plant, including vehicles any load being moved, including the slings, chains and other lifting gear any person working at heights, for example, from an elevating work platform (EWP),

scaffold, or other structure any hand tools, hand control lines, equipment or other material held by a person.

Note: Different approach distances apply for scaffolding work (Section 5) and work in the vicinity of low voltage overhead electric lines near buildings and structures (Section 7).

2.2 Unauthorised Person ZoneTable 1 provides approach distances for:

unauthorised persons performing work in the vicinity of overhead electric lines, including plant, hand tools, equipment or any other material held by a person

cranes (and their loads) and items of mobile plant operated by an unauthorised person in the vicinity of overhead electric lines.

Where a risk assessment determines it necessary, the use of a safety observer should also be considered for work performed by unauthorised persons working outside but up to the approach distances specified in Table 1. The responsibilities of the safety observer are described in Section 2.7.

Table 1: Approach distances for work performed by unauthorised persons

Nominal phase to phase a.c. voltage (volts) Approach distance (metres)Up to and including 132,000 3.0Above 132,000 up to and including 330,000 6.0Above 330,000 8.0Nominal pole to earth d.c. voltage (volts) Approach distance (metres)Up to and including +/- 1500 Volts 3.0 3.0

2.3 Authorised Person ZoneTable 2 provides approach distances for:

authorised persons, with a safety observer, who are performing work in the vicinity of overhead electric lines, including plant, hand tools, equipment or any other material held by a person

1 You should contact your local electricity supply authority to check relevant approach distances as they may have more stringent requirements.


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cranes (and their loads) and items of mobile plant operated by an authorised person with a safety observer in the vicinity of overhead electric lines.

The approach distances in Table 2 are based on: completion of a written risk assessment prior to the commencement of work application of a safe system of work, including a safety observer if determined by the written risk assessment, consultation with the electricity supply

authority regarding the proposed work and compliance with any conditions imposed by the electricity supply authority for the work.

Table 2: Approach distances for work performed by authorised persons, with a safety observer.

Nominal phase to phase a.c. voltage (volts) Approach distance (metres)Insulated low voltage cables up to 1000, including LV ABC

0.5

Un-insulated low voltage conductors up to 1000 1.0Above 1000 up to and including 33,000 1.2Above 33,000 up to and including 66,000 1.4Above 66,000 up to and including 132,000 1.8Above 132,000 up to and including 220,000 2.4330,000 3.7500,000 4.6Nominal pole to earth d.c. voltage (volts) Approach distance (metres)Up to +/- 1,500 1.0 1.0

2.4 No Go Zone – Approval of the electricity supply authorityA no go zone is the area around overhead electric lines or electric parts that forms a safety envelope. A safety envelope is the space encapsulating an item of plant, including attachments such as rotating/flashing lights or radio aerials, categorised as:

a design envelope - the space encapsulating all possible movements of the plant and any load attached under maximum reach, or

a transit envelope - the area encompassing the normal height and width of a vehicle or plant when travelling to or from a worksite.

No part of a person, hand tools, equipment or any other materials held by a person, cranes, vehicles or items of mobile operating plant including the load, controlling ropes and any other accessories may cross into the no go zone while the electrical part is energised without the written approval of the electricity supply authority. This approval should be made available at the worksite.

No go zones apply whenever carrying out work or operating plant (for example tip truck, crane, elevating work platform, concrete pumping truck), around an energised electrical part and the risk cannot be eliminated.

The safest option is to have the electricity turned off and tested or have the lines shifted. This will rule out the need for a no go zone. If the electrical part is high voltage, it must be earthed. If the electricity cannot be turned off, the electric line remains energised and dangerous.

About no go zones

A no go zone extends in all directions, not just sideways; it is all around the electrical part. A person should not enter a no go zone.


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The areas of a no go zone may vary, but it will always exist. Before work commences in the vicinity of an energised electrical part, no go zones should be established.

To decide the correct no go zone in the circumstances, you should consider:

the voltage of the electric line, and

if it is insulated or bare.

If you don’t know these facts, you should ask the electricity supply authority or the property owner.

You should also consider who or what will work in the vicinity of the electric line, for example:o an unauthorised or an authorised persono an operating planto a vehicle.

On site, the authorised person could be the plant operator, supervisor, electrician or worker. Equipped with the right electrical training or experience, the authorised person can work within a smaller no go zone. All of these factors govern the safe approach distance.

2.5 Approach Distances for VehiclesTable 3 provides approach distances for vehicles, mobile plant stowed for transit or with a design envelope up to and including 4.6 metres in height, which are driven by or operated by persons under overhead electric lines.

Table 3: Approach Distances for Vehicles.

Nominal phase to phase a.c. voltage (volts) Approach distance (metres)Low voltage conductors up to 1000 0.6Above LV, up to and including 33,000 0.9Above 33,000 up to and including 132,000 2.1Above 132,000 up to and including 220,000 2.9330,000 3.4500,000 4.4Nominal pole to earth d.c. voltage (volts) Approach distance (metres)Up to and including +/- 1500 Volts 0.9

When assessing the approach distance for a vehicle driven under overhead electric lines several factors should be considered including:

The approach distances for vehicles specified in Table 3 that are based on the fact that the design or transit envelope of the vehicle does not allow any part of the vehicle to come closer than the approach distances specified. This includes the load, exhaust pipe and attachments for example rotating/flashing lights or radio aerials. See Figure 4 below.

Where a work activity involves a person working from, standing on or walking across the top of a vehicle the relevant approach distance specified in either Table 1 or Table 2 should be maintained. For example, this may include the driver of a livestock transporter who may need to access the top of the vehicle to check livestock.

Where, as a result of the work being performed the distance between the conductors and the ground may decrease (for example when constructing a road or levee bank beneath overhead electric lines or where the ground level is raised during the work), then the distance between the vehicle should be continually re-assessed to ensure that the relevant approach distances are being maintained.


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Any additional assessment factors that may be relevant for the operation of the vehicle as described in assessing the relevant approach distance in Section 2.1.

Figure 4: Transit envelope – The maximum overall height of the vehicle.

2.6 Authorised Person

Training and Competence

Persons such as operators of cranes, mobile plant and elevating work platforms who carry out work closer than the approach distances specified in Table 1 and safety observers who observe the work should have successfully completed an appropriate training course (for example Crane and Plant Electrical Safety Course), conducted by a registered training organisation, that relates to work in the vicinity of overhead electric lines.

The registered training organisation, which provides the training and competency assessment should provide the person concerned with a statement of attainment or written certification of his/her successful completion of assessment, that has an identifying number particular to that person.

A person conducting the business or undertaking should maintain appropriate training and assessment records for ‘authorised persons’ and other workers who carry out work in the vicinity of overhead electric lines.

Maintenance of competency

Authorised persons and safety observers should be either re-assessed or re-trained annually to ensure their on-going competency to perform activities associated with work in the vicinity of overhead electric lines.

Re-assessment or re-training should cover as a minimum the knowledge and skills necessary to ensure safe work practices in the vicinity of overhead electric lines, resuscitation procedures, and emergency rescue procedures to be followed in the event of an incident.

Persons who have failed to maintain competency through the regular on-the-job application of learnt skills and knowledge should undertake refresher training and competency assessment.

2.7 Safety Observer The safety observer is a person specifically assigned the duty of observing the work in the vicinity of energised overhead electric lines and associated electrical equipment in order to:


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warn persons or the crane or plant operator so as to ensure the approach distances are being maintained

warn of any other unsafe conditions.

A safety observer should: be used whenever the work activity is likely to be performed in the authorised person

zone be positioned at a suitable location to effectively observe both the overhead electric lines

and plant be able to immediately and effectively communicate with the operator of the crane or

mobile plant, or other persons if required ensure that all persons stay outside the specified approach distance (unless performing a

rescue in accordance with approved procedures or carrying out a specific task that is described in the safe work method statement, for example a crane dogman holding a non-conductive tag line attached to a load suspended from a mobile crane)

not carry out any other work while acting as a safety observer, which includes the passing of tools, equipment or materials directly to the personnel performing the work

not observe more than one work activity at a time monitor the work activity being carried out and have the authority to suspend the work at

any time.

Further guidance and examples of what can go wrong when relevant approach distances are not maintained are provided in Appendix B.


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3. OPERATING CRANES AND MOBILE PLANT – OVERHEAD ELECTRIC LINES

Contact with overhead electric lines can pose a risk of electrocution when operating a crane or other plant. It can be extremely difficult for crane or plant operators to see electric lines and to judge distances from them.

The risks associated with operating a crane or an item of mobile plant in the vicinity of overhead electric lines must be managed. The types of cranes and/or mobile plant include:

cranes (including mobile cranes and vehicle loading cranes) concrete placing booms elevating work platforms load shifting equipment (including forklifts) excavation and earthmoving equipment high load transportation vehicles.

This Section does not apply to cranes and mobile plant when they are retracted and correctly stowed when travelling on a public road or where the design envelope of the crane or item of mobile plant is less than 4.6 metres in height.

Electric lines covered in this Section include: overhead electric distribution lines on poles: high or low voltage overhead electric transmission lines on towers dedicated overhead electric lines used by public transport authorities, for example,

tramways and railways privately owned overhead electric lines.

3.1 Identify hazards

Before operating a crane or item of mobile plant, a worksite inspection should be conducted to identify any potential hazards, such as energised overhead electric lines or other associated electrical equipment.

Electric lines should always be treated as energised unless the operator of the crane or mobile plant has received an access authority or other form of written documentation from the electricity supply authority which allows persons to work within the no go zone. There are two options for operating a crane or mobile plant in the vicinity of overhead electric lines:

have the electric lines de-energised, or stay outside the authorised person zone shown in Figure 5.

Figure 5: Cranes and mobile plant working in the vicinity of overhead electric lines.


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3.2 Assess risks A risk assessment involves considering what could happen if someone is exposed to a hazard and the likelihood of it happening. The risk assessment should consider:

the location and voltage of the overhead electric lines the nature, size and shape of the load to be moved, for example, dimensions, surface

area (particularly the surface area facing the wind) and whether the load is conductive. When in contact with high voltage, material that would normally be non-conductive may become conductive. All materials should be assumed to be conductive unless a competent person can confirm otherwise

the setting up and packing up processes the safe work practices and procedures in use the type of crane, mobile plant, machinery and equipment to be used and its design

envelope stability of crane or mobile plant and suspended loads site conditions, including unexpected movement of the terrain, ground or surface upon

which the crane or plant is located prevailing or unexpected wind strength and direction and weather conditions the qualifications, competency, skill and experience of people doing the work vehicular traffic, pedestrians, or livestock that could interfere with the work the minimum clearance distance from the closest part of the crane or other operating

plant to the electric line whether the load is being carried above the electric lines and may accidentally fall onto

the energised lines, for example, moving a swimming pool from the street over energised electric lines into the yard of a home

the possibility of sway and sag of the overhead electric lines (sway of overhead electric lines is usually caused by wind, while sag may vary as temperatures vary)

possibility of crane or plant becoming energised through voltage induced by adjacent electric lines, especially high voltage lines

how the load being carried by a crane is secured and whether any part of the load may inadvertently move during the operation and encroach on the authorised person zone

the potential for inadvertent movement of the crane or mobile plant, the load, persons and electrical equipment in the area

the functional behaviour of the crane, load or plant that could result in inadvertent contact with overhead electric lines.

Crane or mobile plant operation in the vicinity of overhead electric lines may also require a safe work method statement based on a risk assessment.

Note: A load is any substance, material or object being moved, carried, lifted or supported or which is in rotary or vertical motion, in association with a crane or mobile plant. A load includes persons and equipment located on an elevating work platform.

3.3 Control risks Once the hazards have been identified and assessed, control measures must be implemented to eliminate the hazards so far as is reasonably practicable, or if that is not possible, minimise the risks so far as is reasonably practicable.

Eliminate the hazard and associated risks

This may include: de-energising the electric lines for the duration of the work rerouting the electric lines away from the crane or other operating plant


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replacing existing overhead electric lines with underground electric lines.

Arrangements for de-energising and re-routing lines should be made with the electricity supply authority or person with management or control of the electric line or premises as early as possible when planning work. The de-energising process can take some time and, depending on the circumstances, may delay work. Confirmation should be sought that electric lines have been de-energised.

The person conducting the business or undertaking or operator of the crane or mobile plant should:

discuss options for de-energising or re-routing the electricity supply with the electricity supply authority or in the case of work involving private overhead electric lines, the person with management or control of the workplace (be it land, building, vehicle or installation)

consider working at another time when the electricity supply can be isolated, and investigate whether the section of the overhead electric line that needs to be de-

energised can be isolated, while leaving the remainder connected.

Minimise the risk

If elimination of the hazard is not possible, minimise the risk by implementing control measures in the following priority order:

Substitute the hazard with something safer

This may include another way of performing the work for example: setting up the crane or mobile plant in a position that keeps the design envelope outside

the approach distance separating the hazard from the crane or mobile plant and people by using an alternative

crane or mobile plant which cannot encroach on the approach distances using an effectively tested insulated elevating work platform bucket that could prevent

electric shocks from the exposed energised part to ground via the operating plant. Warning: in spite of the insulated bucket, the worker could still receive an electric shock by touching a current source with one hand and an earth point with the other hand

working at another time when the electricity supply can be isolated.

Isolate the hazard from people

This may include installing or erecting a physical barrier to prevent any part of the machine or the load being moved from encroaching on the authorised person zone. A physical barrier should consist of a non-conductive material for example wood or plastic or alternatively correctly earthed metal and be strong enough to withstand any impact from falling objects, loose materials or contact by the crane or other operating plant. Before any barriers are erected, a risk assessment must be carried out by an appropriately qualified person to ensure the appropriate design and


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correct materials are used. The barrier should be erected safely. This may entail isolating the electricity supply while the barrier is installed.

Use engineering controls

This may include: limiting the hoisting, slewing (i.e. forcible turning or swinging of a crane to a new position

while moving a load) or other movements of the crane or mobile plant with:o mechanical stops or interlocking of the motion of the crane or mobile plant to prevent

it from being moved by electricity within the approach distanceo mechanical constraints on the jib, boom, or other part of the crane or mobile plant

likely to contact energised overhead electric lines or associated electrical equipment as a result of surge or backlash

o using cranes or mobile plant fitted with programmable zone limiting devices. If a limiting device is used, the interlocking or warning system should be designed to ‘fail safe’ or should at least meet category four (4) reliability in accordance with AS 4024.1 Safeguarding of Machinery or a SIL of three (3) under AS 61508 Functional safety of electrical / electronic / programmable electronic safety-related systems. Where the limiting device prevents movement, sudden stopping or the momentum of the load should be catered for.

minimising unexpected movement of the crane or mobile plant through:o additional outriggers, supports or packing to increase the stability of the crane or

mobile planto preparation of the ground or surface, or adjustment or servicing of the crane or mobile

plant, to minimise surge or backlash.

Increased clearances should also be allowed where there is a reasonable possibility of the load or lifting gear (for example crane, hook, chains or slings) moving or swinging towards the overhead electric lines or associated electrical equipment when the crane or item of mobile plant is operated.

Define areas that the crane or mobile plant should not enter by: using rigid or tape barriers to mark off areas under overhead electric lines arranging for the electricity supply authority to mark the limit of the approach distance with

high visibility ‘bunting’ or similar as shown in Figure 6.

Figure 6: Visual tape bunting fitted under overhead electric lines.


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Use administrative controls

This may include: managing and supervising the work to ensure that:

o the work is done very carefully and in an un-hurried, considered manner (haste can be dangerous)

o safe work method statements are rigorously followedo the appropriate persons involved in the work are authorised

making the hazard visible by arranging for the electricity supply authority to effectively identify exposed energised low voltage conductors (up to and including 1000 volts) by using approved visual indicators for example sheeting or sleeves, for example ‘tiger tails’. The ‘tiger tails’ should extend a minimum distance of 5 metres beyond the extremities of where the crane or item of mobile plant will be operating. A competent person should visually inspect the ‘tiger tails’ each day prior to commencing the crane or mobile plant operations. If they have moved or been damaged the electricity supply authority should be contacted to ensure the ‘tiger tails’ are replaced or located in the correct position

planning for emergencies including having fire-fighting equipment suitable for electrical fires an appropriate first aid kit readily accessible on site. Emergency rescue procedures following contact with overhead electric lines are provided in Appendix C

ensuring a safety observer is used whenever a crane, mobile plant or load is in motion and is likely to come closer than the approach distances listed in Table 1 and shown in Figure 3

fitting proximity sensors and warning device to the crane or mobile plant that alerts the operator when the crane or mobile plant has entered energised high voltage overhead electric line zones

using warning signs to indicate the location of overhead electric lines and/or defined work areas (see Figure 7).

Figure 7: Overhead electric lines warning sign.

Use personal protective equipment (PPE)

Appropriate PPE may include: insulating gloves used by anyone who may come into contact with any conducting part of

the crane, plant or load being moved


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standing on a rubber insulating mat standing on an ‘equipotential conductive mat’.

3.4 Workers in contact with the crane, load or mobile plantNo-one should remain in contact with any part of a crane, load or mobile plant and the ground or other earthed situation while the crane or mobile plant is being operated closer than the approach distances listed for unauthorised persons in Table 1 of this Code, unless additional precautions are taken to prevent electric shock.

Operators

The operator should handle the controls of a crane or item of mobile plant while standing on the ground or while in an earthed situation only if:

the controls are effectively insulated (consultation with the electricity supply authority will be necessary to verify effective insulation)

using wireless remote control the operator wears low voltage insulating gloves – provided that the energised electrical

equipment is low voltage and does not exceed 1000 volts for low voltage, the operator stands on a rubber insulating mat 900mm x 900mm x 6 mm

thick that is clean and dry the operator stands on an ‘equipotential conductive mat’ which is electrically connected to

all metalwork associated with the controls.

Other workers

Other workers who are essential to the particular operation of the crane or operating plant, for example a dogger, crane chaser or other worker helping to set up the crane or operating plant, may work within the safety observer zone, provided these workers are not required to have direct contact with any part of the crane, operating plant or load.

Other workers at the worksite may contact the crane, mobile plant or load while standing on the ground or while in an earthed situation only if one of the following control measures is observed:

they wear low voltage insulating gloves – provided that the overhead electric lines or electrical equipment is low voltage

effective insulation is provided on the overhead electric lines or electrical equipment, or the crane, load or mobile plant or its parts to ensure that even if it contacts the overhead electric lines or electrical equipment, no–one would receive an electric shock

control of the load by non-conductive tail ropes whenever uncontrolled motion could allow it to come within the approach distance (as long as the insulating properties of the rope are appropriate to the operating voltage)

they are positioning or removing lifting gear from a crane hook or the load while it is stationary

they are adjusting outriggers, jacks, packings, chocks or similar, as long as the crane, load or mobile plant is not being moved.

Competency requirements

In order to carry out crane and mobile plant operations closer than the approach distances specified in Table 1, the following persons should be authorised as described in Section 2.6 of this Code:

the operator of the crane or mobile plant a safety observer.


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3.5 Work in the Safety Observer Zone

The Safety Observer Zone

A crane or mobile plant is considered to be in the safety observer zone when it is possible that any of the following could enter the authorised person zone of energised electric lines during operation:

any part of the crane or operating plant any person on or working on an elevated work platform any hand tools or other equipment held by anyone involved with the operation the load being moved

The safety observer zone concept is designed to encourage operating plant operators to locate their equipment away from the possibility of encroaching into the authorised person zone. When this is not possible, adopt other suitable precautions to prevent encroachment.

A crane or operating plant is not operating in a safety observer zone when: high voltage electric lines have been de-energised and earthed limiting devices have been installed to warn the operator or prevent any part of the crane,

plant or load being moved from entering the authorised person zone (as long as the limiting device is effective under stress conditions and is regularly inspected and tested by a competent person), or

any part of the crane, plant or load being moved is prevented from entering the authorised person zone by physical barriers or by design of the crane or mobile plant that limits such movement.

The safety observer zone for electric lines on poles and on towers is shown in Figure 8.

Figure 8: Safety observer zone for overhead electric lines on poles and towers


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Safety Observer

A safety observer should be assigned the duty of observing the approach of a crane or mobile plant (and its load) to the energised overhead electric lines and associated electrical equipment. The safety observer should be used whenever the crane, load, mobile plant or persons working from the plant are in motion and are likely to come closer than the approach distances specified in Table 1.

The safety observer should: warn the operator if any part of the crane or plant or load is about to enter the authorised

person zone. Encroachment into the authorised person zone is strictly forbidden not be required to observe more than one crane or operating plant at a time communicate effectively with the operator of the crane or operating plant at all times and

should warn the operator about the approach to the authorised person zone. Specialist communication equipment may be necessary where there is a barrier to communication

not be located on the work basket of an elevating work platform, except where rail mounted elevating work platforms are being used for working on rail traction electrical equipment

be trained to perform the role mark the border of the authorised person zone with suitable markers, for example, red

warning tapes, which can be easily viewed by the crane or plant operator have the authority to suspend the work at any time.

3.6 Work in the Authorised Person ZoneA crane or other operating plant may be in the authorised person zone (see Figure 3) when it is operated by an authorised person.

When a crane or other operating plant is in the authorised person zone, or when it is intended to operate in the authorised person zone, a safety observer or another safe system of work should be used which will prevent contact with the low voltage electric line, or where contact is allowed, prevent damage to the electric line.

Another safe system of work may include one or more of the following precautions: use of an authorised person zone between low voltage electric lines and a crane or other

operating plant. A one metre distance or, where circumstances demand, a greater distance, may be necessary to ensure that contact and possible damage to the electric line does not occur. The distance would need to allow for such risks as inadvertent movement of operating plant due to unstable foundation. A one metre authorised person zone may not be necessary in respect of low voltage communication lines

use of limit switches to prevent the crane or operating plant from contacting the electric line

positioning and design of the crane or operating plant which will prevent the plant from contacting the electric line.

Authorised person

In order to authorise a worker, the person conducting a business or undertaking should first gain approval from the person with management or control of the electrical line to do the work that involves being near it. The person conducting a business or undertaking would need to ensure that the worker has enough technical skill and knowledge to perform the work.

In many instances, approval would need to be sought from an electricity supply authority. However, if it is a private electric line, the owner would need to approve the person to work near the electric line. For example, if the private electric line is on a farm, the person conducting a


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business or undertaking would need to seek approval from the farm owner before the worker can be authorised.

3.7 Cranes and mobile plant

Earthing systems for cranes and mobile plant

The chassis of a crane or item of mobile plant may, where practical, be earthed and bonded. A system of work should be adopted that ensures workers are kept clear of cranes and mobile plant when work is carried out in the vicinity of energised overhead electric lines and that workers are advised of the effectiveness of the earthing system.

Specific advice and guidance about the earthing of a crane or item of mobile plant should be sought from the electricity supply authority.

Notices to be fixed to cranes and mobile plant

Cranes or items of mobile plant intended for use, or used, in the vicinity of energised overhead electric lines should be fitted with a warning notice or label, listing the approach distances for unauthorised persons as set out in Table 1.

The notice or label should be maintained in a legible condition and be displayed at each set of controls and should be readily visible to the operator.


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4. TREE AND VEGETATION MANAGEMENT – OVERHEAD ELECTRIC LINES

The risks associated with persons who carry out tree trimming and vegetation management in the vicinity of energised overhead electric lines must be managed where:

a person or something the person is holding or is in contact with could come closer than the relevant approach distance specified in either Table 1 or Table 2 of this Code

the work creates risk of damage to overhead electric lines or electrical equipment.

Examples of vegetation management in the vicinity of overhead electric lines include: a householder trimming a tree on his or her property a local government work crew (other than those who are authorised persons for clearing

of vegetation around electric lines) performing vegetation clearing or planting or vegetation treatment

a building or road construction contractor performing vegetation clearing or trimming work a person picking fruit from trees.

4.1 Managing risks

An electricity supply authority or the person with management or control of the electric line should ensure that trees and other vegetation are trimmed and other measures taken to prevent contact with an overhead electric line that is likely to cause injury from electric shock to any person or damage to property.

Unauthorised persons carrying out tree and vegetation management

An unauthorised person should not: climb a tree closer than 3 metres to energised overhead electric lines, or cut any branch

that may come closer than 3 metres to energised overhead electric lines as a result of the work

allow any part of their body or anything they are holding or that is attached to their body, or anything they are using, to come closer than the approach distances specified in Table 1 of this Code when carrying out the work in the vicinity of energised overhead electric lines. The only exception is if the person is handling an insulated device which has been tested and found to be safe for use on and near the electrical part.

Work should not be carried out above overhead electric lines or where any part of the tree or vegetation could fall or be carried closer than the approach distances specified in Table 1.

If there is a reasonable possibility of the work being carried out above overhead electric lines or coming closer than the approach distances specified in Table 1 the work should be carried out by authorised persons who have been trained and have current competency in carrying out ‘tree and vegetation management’ in the vicinity of energised overhead electric lines. Work zones for tree management in the vicinity of overhead electric line are shown in Figure 9.


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Figure 9: Work zones for tree management in the vicinity of overhead electric lines.

Authorised persons carrying out tree and vegetation management

Authorised persons who have current competency to carry out ‘tree and vegetation management’ in the vicinity of energised overhead electric lines may carry out the work in accordance with the approach distances specified in Table 2 of this code provided that a safe system of work is implemented, which includes a safety observer.

Tree management inside the No Go Zone – Approval of the Electricity Supply Authority

The no go zone is the area around overhead electric lines or electric parts, forming a safety envelope. No part of a person (including hand tools, equipment or any other material held by a person) or plant (including the load, controlling ropes and any other accessories associated with the plant) may cross into the no go zone without the written approval of the electricity supply authority. The written approval should be available at the worksite.

Work required on tree and vegetation that is inside the no go zone (closer to energised overhead electric lines than the approach distances specified in Table 2 of this Code) should only be performed by authorised persons approved by the electricity supply authority.

No go zones vary according to the voltage, the type of overhead electric lines and the qualifications/experience of the person performing the work.


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4.2 Identify hazards Before undertaking any vegetation management work a worksite inspection should be conducted to identify any potential hazards, such as energised overhead electric lines or other associated electrical equipment.

Hazards may include: branches or other vegetation falling onto electric lines during trimming operations tools such as power saws or power trimmers coming into direct contact with electric lines or

other associated electrical equipment operational characteristics that may present a risk such as cutting equipment, for example,

chain saws, which may ’kick back’, causing equipment to move inadvertently mobile plant, for example an elevating work platform, coming into contact with overhead

electric lines or other associated electrical equipment electric lines becoming broken and falling on the ground, footpath or road wind blowing branches or limbs against overhead electric lines high winds resulting in the loss of control while lowering materials unexpected movement of the worker, mobile plant or the vegetation relative to the worker wet weather making the situation more dangerous.

4.3 Assess risks A risk assessment involves considering what could happen if someone is exposed to a hazard and the likelihood of it happening. The risk assessment should determine the risk of:

injury to a worker (or something he or she is carrying, or something attached to that worker), or

damage to property, plant or equipment that may encroach within the authorised person zone for that work.

This step will help to determine the level of associated risk and establish a priority list based on that risk level. A copy of the assessment should be kept for future reference.

The risk assessment should consider: the location and voltage of the exposed energised part, for example, electric line height of the electric lines whether the electric lines are insulated or bare proximity of vegetation insulating properties of the tools and whether they have been tested and found to be

electrically safe heights of any tools, equipment or machinery to be used, placed or operated in the vicinity

of the electric line size of equipment being operated in the vicinity of the electric line and the equipment’s

operating characteristics, ease of manoeuvrability and conductivity location of overhead electric line supporting structures such as poles and towers in relation

to the work to be performed, for example, vegetation may have attached itself to a pole particular arrangement of supporting structures, for example, there may be stay wires that

are hard to see unexpected movement of the terrain, ground or surface upon which the equipment or plant

is located, perhaps resulting in a corresponding surge or sudden movement of the load towards energised electric lines

prevailing weather, for example, strong wind or water affecting the movement of the plant or its parts

visibility of the overhead electric lines and their associated support structures, such as poles, and particularly stay wires on poles.


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4.4 Control risks Once the hazards have been identified and assessed, control measures must be implemented to eliminate the hazards so far as is reasonably practicable, or if that is not possible, minimise the risks so far as is reasonably practicable. The best means of eliminating the hazards is to prevent people, their plant and equipment, as well as any materials from coming close enough to energised conductors for direct contact or flash over to occur.

In addition to ensuring that the work in the vicinity of overhead electric lines is avoided, other factors should be considered:

always assume an overhead electric line or associated electrical equipment to be energised unless an access authority or other written documentation is received from the electricity supply authority

if a telecommunication cable is encountered, never assume that the operating voltage is harmless

a tree or branch of a tree can conduct electricity even in dry conditions. Never assume that a tree branch can safely rest on or against overhead electric lines. If the tree or branch has the potential during the felling or cutting process to come closer than the approach distances specified in Table 1 the overhead electric lines should be de-energised

trees that have grown into contact with energised overhead electric lines must not be cut by a person who is in an earthed situation (such as standing on the ground or working from within the tree) unless a safe system of work is used that meets the requirements of the electricity supply authority

plant that comes within the vicinity of an overhead electric line may become energised and pose a serious danger to the operator and any bystanders. Ensure that when operating plant (i.e. any machines (including chain saws), tools or equipment) in the vicinity of energised overhead electric lines that the relevant approach distances are maintained. Operations should cease where trees or persons are in danger of coming closer than the relevant approach distances

manage traffic and pedestrians at the worksite to ensure approach distances are maintained and that members of the public are kept at a safe distance. If the work in the vicinity of overhead electric lines requires a change in traffic direction or vehicle speed limits, full traffic control is required in accordance with the Roads and Traffic Authority’s requirements in your state or territory

assess the weather conditions, including electrical storms, significant rain or excessive wind velocities that could impact on the proposed work.


This may include: de-energising the electric line for the duration of the work, or re-routing the service line away from the work area.

Note: De-energising or moving electric lines should be arranged as soon as possible because, depending on the circumstances, it may take some time to arrange.

Minimise the risk

If elimination of the hazard is not possible, minimise the risk by implementing control measures in the following priority order:


This may include another way of performing the work for example: using non-conductive tools designed to reduce the possibility of direct contact with the

overhead electric lines using non-conductive scaffolding instead of metal scaffolding


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having someone else do the work. If the electric line is the property of the electrical supply authority, have the electrical supply authority undertake the work.


This may include the worker clearing the vegetation staying outside the no go zone. Clearing operation would cease where workers, trees or equipment were in danger of coming into the no go zone.


This may include: using mechanical tools or devices using modified tools and equipment using insulated fibreglass extension handles on loppers, instead of a conductive

aluminium extension handles changing the work system.


This may include: planning and documenting the work procedure before starting work using a safety observer to warn people before they encroach into the no go zones using visible markers, such as ‘tiger tails’ installed on electric lines and stay wires to make

them easier to see and locate. ‘Tiger tails’ do not insulate wires.


Appropriate PPE includes the use of effectively electrically tested insulating gloves by anyone who may be at risk of encroaching into the no go zones.

4.5 Trees or branches contacting energised overhead electric linesWhile it is not permitted to work on trees where they (or their branches) may fall on overhead electric lines, it is important to know what action to take if a branch or tree comes into contact with an energised overhead electric line, whether through pruning, wind, storm or other damage.

When this situation arises, do not touch any part of the branch or tree. If any part of a branch is touching energised electric lines, the entire branch may be ‘energised’, including the leaves. Contact with any part of it may result in electric shock, burns or electrocution.

Immediately contact the electricity supply authority and keep all persons clear of the area while waiting for assistance.

Further guidance on operating cranes or mobile plant near overhead electric lines while undertaking vegetation management is provided in Section 3.


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5. SCAFFOLDING WORK – OVERHEAD ELECTRIC LINES

The risks associated with work involving the erection, dismantling and use of fixed scaffolding in the vicinity of overhead electric lines and associated electrical equipment must be managed.

AS/NZS 4576 – Guidelines for Scaffolding sets a 4 metre approach distance for metallic scaffolding used in the vicinity of overhead electric lines. This approach distance should be used as a reference point for persons planning and undertaking scaffolding work. Other contributing factors in this standard may also need to be considered.

For work involving the use of mobile aluminium scaffolding refer to the risk control measures for mobile plant described in Section 3 of this Code.

Construction work carried out on or out on or near energised electrical installations or services is defined as ‘high risk construction work’ and requires the preparation of a safe work method statement (SWMS).

5.1 Identify hazards Before undertaking any scaffolding work where the work might come closer than the 4 metre approach distance specified in AS/NZS 4576 – Guidelines for Scaffolding, a worksite inspection should be conducted to identify any potential hazards.

Hazards may include: energised overhead electric lines and associated electrical equipment deteriorated or broken down insulation on the conductors or electrical equipment scaffolding coming into contact with overhead electric lines the possibility of hand held tools, equipment or materials coming into contact with

overhead electric lines.


the type of work activities being undertaken, tools, equipment, scaffolding and materials being used

proximity of the work activity or scaffolding to the overhead electric lines environmental conditions, for example rain, wind or uneven terrain, which may bring a risk

of unexpected movement of tools, equipment, scaffolding or material held by workers.



This may include: de-energising the overhead electric lines for the duration of the work rerouting the overhead electric lines away from the scaffolding following consultation and

agreement of the electricity supply authority, or replacing existing overhead electric lines with underground cables.


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Minimise the risk

If elimination of the hazard is not possible, minimise the risks by implementing control measures in the following priority order:


This may include erecting a physical barrier on the scaffold to prevent a person or anything held by a person, or attached to the person, encroaching within the 4 metre approach distance.


This may include: substituting the scaffold with another means of access and egress, for example an

elevated work platform using an insulated fibreglass extension handle on a paint roller, instead of a conductive

aluminium extension handle


This may include: planning and documenting safe work method statements before starting work using a safety observer to warn people before they encroach within the 4 metre approach

distance using approved visual indicators, to make the hazard visible by arranging for the

electricity supply authority to effectively identify exposed energised low voltage conductors (up to and including 1000 volts a.c.), for example ‘tiger tails’ shown in Figure 15 of this code.


Appropriate PPE includes the use of electrically tested insulating gloves by anyone who may be at risk of coming closer than the 4 metre approach distance.

A combination of the above control measures is required to be taken to minimise the risk to the lowest level reasonably practicable if no single measure is sufficient for that purpose.

5.4 Specific control measures

In addition to the above, specific control measures are outlined as follows.

Erecting and dismantling scaffolding in the vicinity of overhead electric lines up to and including 33kV

A thorough inspection of the surroundings should be undertaken prior to the erection or dismantling of the scaffold in the vicinity of overhead electric lines. No scaffold work should commence until the presence, location, type and operating voltage of all overhead electric lines are determined by a competent person. Operating voltage is the a.c. voltage (phase to phase RMS) or d.c. voltage by which a system of supply is designated.

Overhead electric lines should be de-energised and an access authority or other form of written documentation obtained from the electricity supply authority if the scaffold and the overhead electric lines is or has the potential to come within the 4 metre approach distance shown in Figure 10 below.

If there is the risk that the 4 metre approach distance cannot be maintained, the electricity supply authority should be contacted to enable the development of a safe system of work for the erection, use and dismantling of the scaffolding.


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Figure 10: The 4 metre approach distance applies in any direction where metallic scaffold is erected, used or dismantled in the vicinity of overhead electric lines.

Where low voltage overhead electric lines (up to and including 1000 volts) cannot be de-energised and isolated, ‘tiger tails’ should be provided and installed by the electricity supply authority for the full length of the scaffolding plus a minimum distance beyond each end of the scaffolding of 5 metres. A competent person should visually inspect the ‘tiger tails’ each day prior to commencing scaffolding operations. If the ‘tiger tails’ have moved or been damaged the electricity supply authority should be contacted to ensure the ‘tiger tails’ are replaced or located in the correct position.

Note: ‘Tiger tails’ are plastic pipe type cable covers, used to provide a useful visual indication to people working in the vicinity of overhead electric lines or stay wires. ‘Tiger tails’ should not be regarded as providing protection against mechanical interference or electrical protection from electrical hazards. ‘Tiger tails’ do not insulate wires.

Electrical wires or equipment that pass through a scaffold should be de-energised or fully enclosed to the requirements of the electricity supply authority. These requirements may incorporate full enclosure of the wires or electrical equipment by a non-conductive material, for example moisture resistant flooring grade particle board, dry timber, dry plywood or similar dry non-conductive material approved by the electricity supply authority.

To prevent a person or anything held by a person, or attached to the person, coming closer than the 4 metre approach distance the electricity supply authority may require the erection of a hoarding on the external face of the scaffolding and, if applicable a suitable enclosure on the internal side of the scaffold described in Section 5.5 and shown in Figure 11.


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Figure 11: Enclosure of overhead electric lines.

5.5 Erected scaffolding – use of a hoarding and enclosure for reduced safety clearances

A hoarding is containment sheeting positioned on the external face of a scaffold that serves as a physical barrier between a worker and energised overhead electric lines and associated electrical equipment.

The A and B clearances shown in Figure 12 are horizontal safety clearances and vertical mechanical clearances from the conductors and will be advised by the electricity supply authority prior to the erection of the scaffolding in the vicinity of the overhead electric lines.

The following installation conditions apply for the use of a hoarding and enclosure for reduced safety clearances:

gaps between fitted sheets of plywood should not exceed 3mm no exposed cut or drilled holes should be permitted in the sheets of plywood


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the scaffolder should be responsible for attaching plywood to the scaffold and ensuring that the arrangement can sustain an appropriate wind load

warning signs should be affixed to the safe side of the hoarding warning of the presence of the electrical hazard on the other side of the hoarding and warning that the hoarding should not be removed

a competent person should visually inspect the hoarding and, if applicable the enclosure on a daily basis to ensure the hoarding and enclosure are in a satisfactory condition and remain impenetrable.

Figure 12: Scaffolding with hoarding.

Further guidance on the erection, dismantling and use of scaffolding is provided in: Code of Practice: Scaffolding Work AS/NZS 4576 – Guidelines for Scaffolding.


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6. AGRICULTURAL WORK – OVERHEAD ELECTRIC LINES

The risks associated with agricultural workers when working in the vicinity of overhead electric lines must be managed.

Examples of such work include: handling irrigation pipes under or in the vicinity of an overhead electric line using lifting or elevating plant or equipment for example grain augers, hay bale elevators,

travelling irrigators or harvesters under or in the vicinity of an overhead electric line moving or relocating agricultural plant, for example folding cultivators, where the transit

(stowed) height of the equipment is greater than its operating height any other work that involves the risk of a person or anything attached to or held by a

person, coming into contact with overhead electric lines.

A person should not work in situations where any part of mobile plant being operated, or any hand tools or other equipment or load being handled by any person involved with the operation are at, or within, the no go zones for the electric line (see Section 2.4 of this Code).

6.1 Identify hazards Before undertaking any agricultural work in the vicinity of overhead electric lines, a worksite inspection should be carried out to identify any potential hazards such as energised overhead electric lines or other associated electrical equipment.

Many people have been electrocuted when metal parts of agricultural plant (for example augers, field bins, harvesters or tip trucks) have come into contact with or close to energised overhead electric lines. Such accidents usually occur when the operator has not lowered the equipment before moving it or has raised the item of mobile plant upwards into the energised overhead electric lines.

Hazards may include: working near and in the process coming into contact with signs, scaffolding or machinery

operating in the vicinity of overhead electric lines driving machinery with tall attachments through paddocks where overhead electric lines

exist operating or moving tipper trucks, mobile silos, field bins, harvesters or other large rural

machinery (cotton harvesters, field irrigators) under or in the vicinity of energised overhead electric lines

moving or re-arranging long metallic irrigation pipes.

Where work is carried out in the vicinity of energised overhead electric lines, the height and location of the electric lines needs to be identified as part of an overall site hazard identification process. The local electricity supply authority can assist with this process.

Operators of agricultural plant and equipment also should be made aware of the design height and the transit (stowed) height of the mobile plant they operate.

6.2 Assess risks A risk assessment involves considering what could happen if someone is exposed to a hazard and the likelihood of it happening.The risk assessment should consider:


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the type of work activities being undertaken or agricultural equipment being used proximity of the work activities to the overhead electric lines and the height of the electric

lines location of overhead electric line supporting structures for example poles and towers in

relation to the work to be performed, for example, a pole may be located where a large self propelled machine, for example a harvester, is required to reverse or turn

visibility of the overhead electric lines and their supporting structures, for example stay wires on poles

how often the work will need to be done in the vicinity of the overhead electric lines proximity of stationary or fixed plant and equipment to the overhead electric lines, for

example grain silos and stock crate gantries voltage of the exposed energised part, for example electric line whether the lines are insulated or bare heights of any tools, equipment or machinery to be used, placed or operated in the vicinity

of the electric line size of equipment being operated in the vicinity of the electric line and the equipment’s

operating characteristics, ease of manoeuvrability and conductivity the possibility of sway and sag of the overhead electric lines (sway of overhead electric

lines is usually caused by wind, while sag may vary as temperatures vary) unexpected movement of the terrain, ground or surface upon which the equipment or

plant is located, potentially causing a surge or sudden movement of the load towards energised electric lines

prevailing weather, for example, strong wind or water affecting the movement of the plant or its parts.



Eliminating the hazard may include: de-energising the lines for the duration of the work relocating the overhead electric lines or having them installed underground in consultation

with the electricity supply authority relocating plant or structures, such as a silo, away from the overhead electric lines. Lower

augers before transporting to eliminate the risk of contacting overhead electric lines and keep mobile irrigator sprayed water at least 8 metres away from overhead electric lines.

Arrangements for de-energising and re-routing lines should be made with the electricity supply authority, or person with management or control of the electric line, as early as possible when planning work. The de-energising process can take some time and depending on the circumstances, may delay work. Confirmation should be sought that electric lines have been de-energised.

Minimise the risk



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This may include: using another means to perform the task for example filling a silo through a ground-level

filler pipe on the silo rather than using a truck-mounted auger. This alternative would eliminate the risk of contact with energised overhead electric lines.


This may include erecting a physical barrier to prevent any part of the plant or equipment encroaching into the no go zone. A physical barrier should consist of a non-conductive material for example wood or plastic or alternatively correctly earthed metal. It should be strong enough to withstand any impact from falling objects or loose materials. Before any barriers are erected, a risk assessment must be carried out by an appropriately qualified person to ensure the appropriate design and correct materials are used. The barrier should be erected safely. This may entail isolating the electricity supply while the barrier is installed.


This may include: limiting the height of all mobile plant in order to maintain safety clearances from overhead

electric lines using limiting devices to prevent equipment from entering the no go zones. If a limiting

device is used, the interlocking or warning system should be designed to ‘fail safe’ or should at least meet category 4 reliability in accordance with AS 4024.1 Safeguarding machinery or ISO 13849-1:2006 Safety of machinery – Safety related parts of control systems – Part 1: General principles for design. Where the limiting device prevents movement, sudden stopping or the momentum of the load should be catered for.


This may include: developing work procedures and travel routes for equipment and vehicles that ensures

workers, their equipment and containers for example field bins, stock and tipper trucks do not operate in the vicinity of or under energised overhead electric lines

using a safety observer to warn the operator of plant or equipment whenever there is danger of entering the no go zones

installing warning signs on gates to paddocks or on roadways where overhead electric lines exist (see Figure 13)

using visible markers, for example ‘tiger tails’ installed on electric lines and stay wires to make them easier to see and locate. Note: ‘tiger tails’ do not insulate wires.


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Figure 13: Overhead electric lines warning sign.


Appropriate PPE includes effectively maintained insulating gloves, rubber soled boots and safety helmets when agricultural plant or equipment is being operated in the vicinity of overhead electric lines.

If no single measure is sufficient to minimise the risk to the lowest level reasonably practicable, a combination of the above control measures is required to be taken.

6.4 Particular circumstancesWhere plant or equipment consists of a vehicle, possibly including an attached trailer, the plant or equipment should be driven under an overhead electric line only under the following circumstances:

the plant or equipment has a fully-enclosed driver’s cabin the driver remains completely within the cabin a clearance between the plant or equipment not exceeding those for unauthorised

persons in Table 1 and shown in Figure 3 is maintained at all times no other person is in or on the plant or equipment or in contact with the plant or

equipment or at risk of encroaching within the no go zone of the energised exposed parts moving or extendable parts are retracted and secured.

Emergency rescue procedures following contact with overhead electric lines are provided in Appendix C.


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7. LOW VOLTAGE OVERHEAD ELECTRIC LINES NEAR BUILDINGS AND STRUCTURES

The risks associated with people working in the vicinity of low voltage service lines must be managed. This work may involve:

painting or maintenance work undertaken in the vicinity of low voltage overhead lines erection of scaffolding in the vicinity of a low voltage overhead line operation of motor vehicles (concrete trucks, furniture removal vans, etc) in the vicinity of

low voltage overhead lines minor building work in the vicinity of low voltage overhead lines, or any other non-electrical work where there is a risk of contact with a low voltage overhead

line.

Electric lines covered by this Section and shown in Figure 14 are any ‘low voltage overhead service lines’, including:

electricity supply authority’s low voltage overhead lines including service lines low voltage overhead lines forming part of consumers’ installations insulated low voltage aerial conductors and associated electrical equipment that are

connected from the point of supply (either the overhead electric pole located on the street or the consumer’s boundary) and terminated on the consumer’s building, pole or structure at the point of attachment

insulated low voltage aerial consumers’ mains and associated electrical equipment forming part of the consumer’s electrical installation.

Figure 14: Low Voltage Overhead Service Lines.


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7.1 Approach DistancesTable 4 provides approach distances for unauthorised persons:

performing minor building work in the vicinity of low voltage overhead service lines, (including hand tools held by a person)

operating cranes (and their loads) and items of mobile plant in the vicinity of low voltage overhead service lines

handling metal materials in the vicinity of overhead service lines (for example scaffolding, roofing materials and guttering)

handling non-conductive materials in the vicinity of overhead service lines (for example timber, plywood, PVC pipes and guttering)

driving or operating a vehicle under overhead service lines.

The approach distance specified in Table 4 below is based on the fact that the design or transit envelope of the vehicle does not allow any part of the vehicle to come closer than the 0.6 metre approach distance specified.

Table 4: Approach distances for work in the vicinity of low voltage overhead service lines.

Unauthorised Persons (metres)

Hand held tools

Operation of crane or mobile plant

Handling of metal materials (e.g. scaffolding, roofing, guttering, pipes, etc)

Handling of non-conductive materials (e.g. timber, plywood, PVC pipes and guttering, etc)

Driving or operating vehicle

3.0 3.0 4.0 1.5 0.6

7.2 Identify hazards Before undertaking work in the vicinity of low voltage overhead service lines where the work might come closer than the specified approach distances, a worksite inspection should be carried out to identify any potential hazards.

Hazards may include: bare exposed energised conductors deteriorated or broken down insulation damaged overhead service line mains connection box or damaged insulation around

conductor clamps deterioration of earthing of exposed conductive parts that are required to be earthed voltage of the line is higher than the expected low voltage (240/415 volts a.c.), and the possibility of hand held tools and equipment coming into contact with exposed

energised parts.

Note: If the overhead line is found to be a high voltage line, this section does not apply If the voltage of the line cannot be determined, the line should be deemed as a high

voltage line If you cannot determine whether the line is effectively insulated, the line should be treated

as being bare.


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the type of work activities being undertaken, including how safe access and egress will be made to the worksite

tools or equipment being used, and the risk of mechanical damage to the low voltage overhead service lines if inadvertent contact is made with the conductors and electrical equipment. Examples may include:o handling a sheet of roofing material that inadvertently comes into contact with the

service lineso use of cutting or grinding tools where the operator could lose control and come within

the 0.5 metre approach distanceo use of a heavy electric disc sander to sand timber near the point of attachment of a

service line; this may impose a high risk of encroaching the no go zone if control were lost. The risk of damage to and contact with the line and consequent electric shock is high if the sander touched the line. Manual sanding should be considered

proximity of the work to the low voltage overhead service lines environmental conditions, for example rain, wind or uneven terrain, which may bring a risk

of unexpected movement of tools or equipment held by workers.

Visual Examination of low voltage overhead line

An insulated low voltage overhead line should be examined for visible defects. If the line is part of a customer’s installation, a licensed electrical worker should assess the line. If the line is the property of an electricity supply authority, either an electrical worker with relevant experience or the electricity supply authority should be engaged to have the line assessed.

The line is visually checked to ensure that: the insulation is intact, with no tears, cracks or other physical defects, and there are no

exposed energised parts along the line there are no exposed energised parts anywhere on the line.



This may include: de-energising the lines for the duration of the work. This should be confirmed by the

person with management or control of the electric line re-routing the low voltage overhead service line away from the worksite in consultation

with the electricity supply authority or in the case of overhead service lines forming part of the consumer’s electrical installation, the person with management or control of the premises.

Minimise the risk



This may include: using non-conductive scaffolding instead of metal scaffolding


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if work has to be carried out in close proximity to the point of attachment and the electricity cannot be isolated, arrange for the electricity supply authority to fit insulated matting and ‘tiger tails’ at the point of attachment and over the overhead service lines before the work commences (see Figure 15 below).


This may include erecting a physical barrier to prevent a person or anything held by a person, or attached to the person, encroaching into the no go zone. A physical barrier should consist of a non-conductive material for example wood or plastic or, alternatively, correctly earthed metal. It should be strong enough to withstand any impact from falling objects or loose materials. The barrier should be erected safely. This may entail isolating the electricity supply while the barrier is installed.


This may include: sanding by hand near the point where an overhead line meets a building, rather than

using an electric disc sander using an insulated fibreglass extension handle on a paint roller, instead of a conductive

aluminium extension handle.

Figure 15: Insulated matting and tiger tail fitted to overhead service line.


This may include: planning and documenting work procedures before starting work using a safety observer to warn people before they encroach into the no go zone using visible markers, for example ‘tiger tails’ installed on electric lines and stay wires to

make them easier to see and locate.


Appropriate PPE includes electrically tested insulating gloves worn by anyone who may be at risk of encroaching into the relevant approach distance.

If no single measure is sufficient to minimise the risk to the lowest level reasonably practicable, a combination of the above control measures is required.

Emergency rescue procedures following contact with overhead electric lines are provided in Appendix C.


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8. TRANSPORTATION OF HIGH LOADS – OVERHEAD ELECTRIC LINES

The risks associated with road transport operators contacting energised exposed parts, for example, when moving a high load with a vehicle in the vicinity of overhead electric lines of an electricity supply authority must be managed. This Chapter provides guidance on responsibilities and safe procedures to these operators, their workers and others.

Apart from electrical risks, there may be other obstacles or risks associated with transporting such loads, for example clearance from trees and traffic lights. This Code does not cover such risks. This Code also does not cover permits and other requirements in relation to the transport of over dimension loads from other authorities, for example local council, rail or transport authorities.

8.1 Meaning of specific terms used in transporting high loads

Assessing means checking the suitability of, and the requirements necessary for, safe transport of a proposed high load by reference to the electricity supply authority’s records. If this is not possible, scoping should be undertaken.

Escorting is facilitating safe passage of a high load through an electricity supply authority’s network, including any activities necessary to achieve safety.

Escort service provider is a person conducting a business or undertaking who provides services to escort a vehicle in accordance with the electricity supply authority’s electrical safety precautions.

Notification is a road transport operator’s advice to the electricity supply authority of the intended route and the specification of a high load.

Road transport operator is a person conducting a business or undertaking who transports a load more than 4.6 metres high.

Scoping is checking the suitability of, and the requirements necessary for, safe transport of a proposed high load by physically checking the intended route. Allowances should be made for changes in the road profile, for example, dips and the distance between front and rear wheel axles. (Figure 16 shows an example of a problem caused by changes to the road profile.) Scoping may not be required where the suitability for transporting a high load over a particular route can be determined by assessment.

Scoping service provider is an electricity supply authority or a person conducting a business or undertaking who carries out scoping or assessing in accordance with an electricity supply authority’s high load safety precautions.

Qualified person is a person who has successfully completed a high load transportation scoping course or its equivalent provided or authorised by an electricity supply authority. The evaluation of the person’s qualification will be made by the relevant electricity supply authority.


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Figure 16:The road profile can affect the clearance height of over dimension loads.

8.2 Transport requirements for high load categoriesElectricity supply authorities have certain requirements that must be met before high loads can be moved with a vehicle in the vicinity of overhead electric lines of an electricity distribution network.

What is a high load and what requirements apply?

There are four categories of high load. The transport requirements of high loads depend on the height of the load above the roads. Three of these categories have special requirements. The categories and requirements are set out in Table 5.

Table 5: Categories and requirements for high loads being transported

Category Number

Maximum transport height of load above road

Transport Requirements

1 Up to 4.6 metres Transport can be carried out without any notification.2 Over 4.6 metres, but not

exceeding 5.0 metres Notification to the electricity supply authority is

required. The route should be assessed by a qualified person

taking into account the electricity supply authority’s advice about the network including information in the notification and any safety advice.

Generally no escorting will be required, depending on the outcome of scoping/assessment.

3 Over 5.0 metres, but not exceeding 5.5 metres

Notification to the electricity supply authority is required.

The route should be assessed by a qualified person taking into account the electricity supply authority’s safety advice.

An escort may be required in accordance with the electricity supply authority’s requirements or depending on outcome of scoping/assessment.


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4 Exceeding 5.5 metres Notification to the electricity supply authority is required.

The route should be assessed by a qualified person taking into account the electricity supply authority’s advice about the network and any safety precautions advised by the network.

An escort is required.

Category 1 (height of 4.6m or less):

Transport can be carried out without any notification to the electricity supply authority.

Category 2, 3, 4:

Notification should be forwarded to the electricity supply authority. Notification about transporting a high load should contain the following:

dimensions of the load. The maximum travel height of the load should be determined by combining the height of the object and the vehicle used for transportation. If unable to predetermine the exact measurement, the maximum possible height should be used for scoping or assessing purposes

route specification time or times during which transport is required to take place details of the service provider responsible for facilitating the transport of the high load and

providing safety precautions.

Copies of the notification form can be obtained directly from the electricity supply authority or their website.

8.3 Responsibilities – Electrical safety

Electricity supply authority

Responsibilities regarding the transport of high loads are to: provide relevant electricity network information to transport operators and escort service

providers advise precautions for scoping/assessing high loads and escorting high loads, which

address the electricity risks of these activities, and provide written authorisation.

Escort service provider – electrical safety

Responsibilities regarding the transport of high loads are to: understand no go zone concepts and their application ensure that only persons with appropriate training are engaged to perform relevant

activities associated with escorting the high load inform the electricity supply authority if load and route do not conform to the notification

details use only specialised equipment, especially where the equipment may and can come into

contact with exposed energised parts notify the electricity supply authority of operational electrical safety problems that have

been identified, for example, damage to network assets, and direct road transport operators to ensure electrical safety is maintained.


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Road transport operator – electrical safety

Responsibilities regarding the transport of high loads are to: notify the electricity supply authority of the intention to move a high load in the vicinity of

network assets provide accurate information about high loads to the electricity supply authority comply with precautions required by the electricity supply authority comply with directions of escort provider, and contact the electricity supply authority about any operational matters affecting electricity

safety, for example if the high load transport encountered electric lines lower than the minimum clearance required, where an escort service provider is not required.

Scoping service provider or network assessor – electrical safety

Responsibility regarding the transport of high loads is to provide accurate information about the network through which the high load is to be transported.

Note: The categories and requirements for the transportation of high loads are based on Queensland requirements. For specific requirements in other jurisdictions contact the relevant Transport/Traffic Authority and the Electricity Supply Authority in your state or territory. For further information see Appendix D.


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9. ELECTRICAL RISKS UNDERGROUND AND IN BUILDINGS

Regulation 166 requires that a person conducting a business or undertaking must ensure, so far as is reasonably practicable, that no person, plant or thing at the workplace comes within an unsafe distance of an underground electric line. If this is not reasonably practicable, the person must ensure that a risk assessment is conducted in relation to the proposed work and control measures implemented are consistent with the risk assessment and, if an electricity supply authority is responsible for the electric line, any requirements of the authority.

The risks associated with people working in the vicinity of electrical installations or underground electrical services that involve potential contact with exposed energised parts must be managed.

Examples of such work include: a builder removing a sheet of plasterboard from a stud wall and thus creating a risk of

contact with exposed energised parts, for example, an electrical accessory for example a socket outlet

a plumber cutting a water pipe in a building where there could be an electrical cable next to the water pipe

a fencing contractor digging holes where an electrical cable could be buried.

Construction work carried out on or out on or near energised electrical installations or services is defined as ‘high risk construction work’ and requires the preparation of a safe work method statement (SWMS).

9.1 Identify hazards

Before undertaking any work, the person conducting a business or undertaking, whether at a construction site or not, must find out from appropriate sources what underground electrical services could create a risk if contacted or damaged. This information must be considered when planning work. A written record of this information should be kept.

Hazards may include: any electric lines or equipment installed in building cavities that may become accessible

when:o a part of the building covering the cavity has been removedo work is being carried out in the building cavity

conductive material or fixings that may inadvertently contact energised parts, for example metallic sarking or metallic thermal insulation being installed in or removed from a building

work activities that could involve risk of damage to electric line or cables, for example drilling or sawing

work done in a building or structure where the existence of electric lines and equipment is not known

excavating or driving implements into the ground (for example star pickets) where underground services may be located.


tools damaging cables or equipment, for example:o when digging, driving equipment or excavating where buried electrical cables may be

presento when demolishing part or whole of a building


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o when installing a building component or material, for example, using screws to fix a bracket to a wall where the screw could penetrate a cable installed behind the wall surface

cables or equipment being concealed in a work location.

If it is not known whether cables, conduits, equipment or situations form an electrical safety risk, you should either assume that the risk exists, or have a qualified person investigate and report.

If excavating in a public place, suitable means should be used to identify any electrical cables that could be present. Suitable means may include:

Call Dial Before You Dig, a free enquiry service for information on underground assets anywhere in Australia. This organisation will advise if electrical cables owned by one or more of its contributory members are located in the vicinity of your worksite. In addition, definite cable locations can be determined by special arrangement with the organisations. Dial Before You Dig can be contacted by:

o phone on 1100; oro submit an online enquiry at www.1100.com.au

Contact relevant authorities about any cables they may have placed in the vicinity of the excavation. Authorities may include:

o electricity supply authoritieso communication companieso local government authoritieso water authorities.

In some instances, customers of electricity supply authorities have authority to place electricity cables in public places. If excavating on private property, contact the owner or occupier of the premises about buried cables before starting work.


Where the risk is not known, it should be assumed that an electrical risk could exist. For example, if you cannot determine exactly where an underground cable is, you should dig carefully to avoid accidental damage. This may mean digging only by hand. Where the risk is known, for example where an electrical conduit contains an energised low voltage circuit and there is a risk the conduit could be cut or scraped with a power tool, suitable precautions should be taken. This may mean using hand tools instead of power tools.


This may include having the electricity supply to the circuit isolated. Sometimes, when many cables and circuits come from a switchboard, identifying the isolation point for a particular cable is not easy. A qualified person should be engaged to do the isolation work. For example, if the work involves building demolition and isolating supply is the risk control measure, it may be necessary to have the electricity supply authority disconnect the supply. De-energising electric lines should be arranged as soon as possible because depending on the circumstances, it may take some time to arrange.


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http://www.1100.com.au/

Minimise the risk


Substitute the hazard with a safer option, process or equipment

This may include: welding a bracket to a column, which may result in excessive heat and damage to

adjacent electrical cable, during the welding process consider bolting the bracket to the column consider hiring a person with the relevant electrical qualification to do the job.


This may include installing a physical barrier to prevent accidental contact between a hand-held tool, for example grinder and the exposed energised parts in the wall. A physical barrier should consist of a non-conductive material for example wood or plastic or alternatively correctly earthed steel and be strong enough to withstand any impact from falling objects or loose materials. The barrier should be erected safely. This may entail isolating the electricity supply while the barrier is installed.

Redesign equipment or work process

This may include using a less intrusive method of carrying out the activity, for example when cutting a hole for a door through an existing stud and plaster wall, scoring and breaking the plaster rather than sawing it through will reduce the risk of damage to any cables, which may be in the wall.


This may include: authorisation to conduct the work training regime to identify the hazards and perform the work safely.


Appropriate PPE includes the use of effectively electrically tested insulating gloves and/or fire retardant clothing.

9.4 Notes on cable identificationElectric lines and cables are manufactured in many different ways. Not all cables are covered with thermoplastic sheath, although these are common and often well known in the building industry.

Electrical cables have different shapes and appearances. For example, cables can be circular, oval, flat, or ribbed in cross section. These cables can also be of any colour.

Some electric cables consist of a copper sheath with copper conductors within the sheath and a mineral insulation separating the conductors and sheath. These cables look and feel identical to copper water pipe or gas pipe. Cables of this kind could also be made of other metals for example stainless steel and aluminium.

Cables in buildings and structures can operate at low or high voltages, for example, cables supplying a transformer in a building may be energized at 11,000 volts (11kV).

Some installed cables may be exposed while others may be concealed in many ways, for example:


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in wall, floor and ceiling cavities behind joinery - skirting boards and pelmets in structural parts of buildings - hollow steel studs and supporting columns.

Electrical conduits are often made of different materials and constructed differently for example: PVC rigid conduit from 16mm or 5/8 inch outside diameter (OD) to 150mm or 6 inch OD is

generally light grey; if the conduit is heavy duty and suitable for underground use, it may be orange (PVC conduit for protection against high temperatures is black)

PVC flexible conduit or flexible hose PVC corrugated conduit screwed metal conduit, generally made from galvanized steel split metal conduit (obsolete but still widely used) and generally painted black cable trunking, rectangular or square in cross section, and in a wide range of sizes, made

of steel or plastic cable tray, generally galvanized steel in a wide range of sizes and styles.

Further guidance on managing risks associated with excavation is provided in the Code of Practice: Excavation Work.


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APPENDIX A – DEFINITIONS

Conductor means a wire, cable or form of metal designed for carrying electric current.

De-energised (dead) means separated from all sources of supply but not necessarily isolated, earthed, discharged or out of commission.

Earthed means directly electrically connected to the general mass of earth so as to ensure and maintain the effective dissipation of electrical energy.

Electrical part means an exposed part or an overhead insulated electric line.

Electrical work means connecting electricity supply wiring to electrical equipment or disconnecting electricity supply wiring from electrical equipment; or installing, removing, adding, testing, replacing, repairing, altering or maintaining electrical equipment or an electrical installation.

Electricity Supply Authority means a person or body engaged in the distribution of electricity to the public or in the generation of electricity for supply, directly or indirectly, to the public. An electricity supply authority may also be known as a network operator.

Energised (live) means connected to a source of electrical supply or subject to hazardous induced or capacitive voltages.

High voltage means exceeds low voltage.

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, and to mitigate the danger of shock or injurious leakage of current.

Isolated (specific electrical usage) means separated from all possible sources of electrical energy and rendered incapable of being energised unintentionally.

Low voltage means exceeds extra-low voltage and does not exceed 1000 volts alternating current (1000 V a.c.) or 1500 volts direct current (1500 V d.c.).

Voltage means a potential difference between conductors or between conductors and earth.


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APPENDIX B – CASE STUDIES - INCIDENTS AND SCENARIOS

A variety of examples are provided to illustrate the risk management process and bring together the practical advice of this Code. The examples created here highlight parts of this Code that can be used to manage risks of working in the vicinity of overhead electric lines and underground electrical services to meet electrical safety obligations and avoid death, serious injury and damage to property.

Case 1: Incident – Mobile Crane OperationsA mobile crane came into contact with 132,000 volt overhead electric lines that were located adjacent to a worksite. At the time of the incident the crane driver had slewed the boom of the crane towards the overhead electric lines, which resulted in the lifting chains swinging outwards, making contact with the electric line.

Luckily no persons were injured, however the crane sustained extensive damage to the tyres, lifting rope and electrical system on the crane.

Contributing factors and relevant sections

Failure to: maintain relevant approach distance to the electric lines and take account of the possibility

of the lifting chains swinging towards the overhead electric lines when the crane was operated

carry out an adequate risk assessment of the worksite implement appropriate risk control measures for the work use a safety observer to observe the crane operations near the electric lines.

Case 2: Setting up a Mobile Concrete PumpAs the project manager, Kevin understands and manages his Workplace Health and Safety obligations but he also knows that electric line safety is just as essential. For the type of projects he uses concrete pumps regularly. An important part of setting up concrete pumping equipment for a project is to consider the vicinity of overhead electric lines in the risk management process.

with his contractors Kevin makes certain that he has identified the no go zone minimum clearance distance for the concrete placement boom in consultation with the electricity supply authority and allowing for sway and sag of the lines. He documents this all in a risk assessment

Kevin ensures the pump is able to be set up on solid ground to prevent inadvertent movement of booms into no go zones

he makes certain that the safety observer watches while pump operators set up and that they keep the pipes away from no go zones and parallel to the ground where possible

ensures a safety observer is present to warn the operator when the placement boom approaches the no go zone.

Case 3: Incident – Scaffolding WorkA worker died and three apprentice roof plumbers were injured when attempting to move an 8.9 metre high aluminium scaffold at a construction site. At the time of the incident the workers were moving the mobile scaffold over soft sand when the castor wheels located at the base of the scaffold sank into the sand causing it to fall and make contact with 33,000 volt overhead electric lines that were located adjacent to the construction site.


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Failure to: carry out an adequate risk assessment of the worksite to account for the ground conditions

at the worksite implement appropriate risk control measures for the work.

Case 4: Incident – Farm MachineryA farmer operating a harvester on his own property received a fatal electric shock when the raised delivery chute contacted 11,000 volt overhead electric lines. The farmer was aware of the electric lines and had previously warned others to stay clear.


Failure to: maintain relevant approach distance to the electric lines carry out an adequate risk assessment of the worksite and implement appropriate risk

control measures to ensure no go zones are adhered to.

Case 5: Incident – Irrigation Pipes on a Rural PropertyWhile attempting to remove vermin from metal irrigation pipes, a farmer working in a field received a fatal electric shock when he raised an irrigation pipe into 22,000 volt overhead electric lines above trying to shake out the vermin blocking the pipe. The electric line height was correct.


Failure to: identify the risk of raising objects into the overhead electric lines carry out a risk assessment of the worksite and implement appropriate risk control

measures.

Case 6: Rural Workplace, Cane HaulageRay, a cane farmer, attended a safety conference run by his growers association and heard a presentation from the local electricity supply authority about electric line safety. The presenter highlighted the need for cane haul out and harvesting contractors to manage the risks around overhead electric lines. Ray had previously attended a training program about safe working near overhead electric lines which equipped him with the knowledge to manage the risk by introducing a number of risk control measures for crane haulage activities at their designated rail siding delivery point.

Ray’s risk assessment identified that electric lines near the delivery point raised the possibility of cane haulers entering the no go zone when lifting their bins

A designated bin lift and tip point (administrative risk control measure) was introduced via signage containing the instruction ‘Bins not to be lifted before this point’

Ray contacted the electricity supply authority who installed flag markers on the electric lines crossing near the cane delivery point to make them more visible to operators.

Case 7: Incident – Tip Truck OperationA tip truck contacted an 11,000 volt overhead electric line causing it to break and fall to the ground striking a worker who was at the worksite. At the time of the incident the tip truck was delivering a load of granulated bitumen to the worksite when the tip tray of the truck was raised upwards into the overhead electric lines.


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Failure to: plan the work and identify the risk of the overhead electric lines maintain the relevant approach distance to the overhead electric lines and take account of

the height of the raised tray when the load was dumped at the worksite carry out a risk assessment of the worksite implement appropriate risk control measures for the work use a safety observer to observe the truck operations in the vicinity of the electric lines.

Case 8: Safety Observer for a Crane in the Vicinity of Electric LineKevin’s Sign Company occasionally manufacturers and installs tall advertising signs by the roadside near where overhead electric lines exist. Kevin is aware of the need to manage the risk of overhead electric lines and has had a consultant assist in preparing and documenting a risk management manual. In Kevin’s workshop, work is about to begin on the design and construction of a new sign for a shopping centre. The company’s safe work procedures are applied at the beginning of each new job. Kevin needs to visit the site to check some dimensions and carry out a site risk assessment.

as part of the company’s documented safe work procedure, Kevin’s site visit identified the risk of overhead electric lines

Kevin contacted the electricity supply authority and received advice on the electric lines to allow him to assess the no go zone distances and the need to use a safety observer

Kevin discusses his requirements with his crane contractor who has also visited the site. Kevin uses this operator because he has been given a copy of their safe work procedures and can check the qualifications of operators easily

on the day of the sign’s installation, clear instructions are given to the crane driver and the safety observer

the dogger that assisted on the day is trained to know his responsibilities as he takes on the safety observer role, has radio communication with the operator and is in a position to clearly see the job and can stop it at any time.

Case 9: Incident – Working around Electrical Risks in BuildingsA builder working near a switchboard was electrocuted when one of the nails he was using to fix panelling pierced the consumer’s mains feeding the switchboard. The building’s wiring was in accordance with the wiring rules.


failure to carry out a risk assessment of the job near the switchboard and implement appropriate risk control measures.

Case 10: Work on a Rural Property - FlashoverA 17 year old rural worker received a fatal electric shock due to a flashover when a steel flagpole came into close proximity with an 11kV overhead electric line that was located above the entrance to a rural property. At the time of the incident the worker was attempting to erect the 5.2m flag pole at the main entrance gate to the property.


Failure to: identify the hazard of the overhead electric lines and implement appropriate risk controls.


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APPENDIX C – EMERGENCY RESCUE PROCEDURE

Should contact be made with an energised overhead electric line or a flash-over occurs between an energised overhead electric line and a crane or an item of mobile plant, the following actions shall be taken:

An attempt should be made to break the machinery’s contact with the energised overhead electric line by moving the jib or driving the machine clear.

If it is not possible to break the contact with the energised overhead electric line, the operator of the crane or mobile plant should remain inside the cabin of the crane or on the plant item. The electricity supply authority should be called immediately to isolate electricity to the energised overhead electric line. The operator should remain in place until the electricity has been isolated, and the ‘all clear’ given by the electricity supply authority.

If it is essential to leave the cabin or the operator’s position due to fire or other life threatening reason, then jump clear of the equipment. Do not touch the equipment and the ground at the same time. When moving away from the equipment, the operator should hop or shuffle away from the plant item (with both feet together) until at least eight metres from the nearest part of the crane or plant. Under no circumstances run or walk from the crane or item of plant as voltage gradients passing through the ground may cause electricity to pass through the body resulting in an electric shock.

Warn all other persons and members of the public to keep 8 metres clear from the crane or item of plant as shown in Figure 17. Do not touch or allow other persons to touch any part of the crane or plant item and do not allow persons to approach or re-enter the vehicle until the electricity supply authority has determined the site safe. Remember electricity flows through the ground, so an electric shock could be received from walking close to the scene. If the crane or plant operator is immobilised, ensure the electricity supply has been isolated and the site made safe before giving assistance.

Unauthorised, unequipped persons should not attempt to rescue a person receiving an electric shock. All too often secondary deaths occur because others get electrocuted trying to help earlier victims. If the crane or plant operator is immobilised, ensure the electricity supply has been isolated and the site has been made safe before giving assistance.


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Figure 17: Affected area surrounding mobile plant when in contact with an energised overhead electric line

Post – incident inspection by a competent person

When a crane or item of mobile plant has been in contact with an energised overhead electric line, it should checked by a competent person for any damage to the components of the crane or mobile plant. Any actions recommended by the competent person are to be completed before the crane or mobile plant is returned to service.

Tyres on cranes and mobile plant that have been in contact with overhead electric lines where electrical flash-over and current flow occurs through the rubber tyres should be considered as a potential hazard. These rubber tyres may catch fire, with the obvious potential for them to explode. Additionally, a lesser known danger may occur, which results when combustion takes place within the tyre, with no apparent external signs. When excessive heat is developed in or applied to a tyre as in the case from contact with overhead electric lines, it can initiate a process known as pyrolysis, which is the decomposition of a substance by heat. This can generate a build up of flammable gases and pressure within the tyre, which may ultimately rupture or explode.


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Vast amounts of energy can be released by a tyre explosion, often leading to significant equipment damage, serious injuries or fatalities. Pyrolysis related explosions are very unpredictable, and have been known to occur immediately or up to 24 hours after initiation. An explosion can occur where no fire is visible and the danger area can be up to 300 metres from the tyre.

Any rubber tyred crane or plant item involved in an incident where contact is made with overhead electric lines which results in discharges or flash-over of electrical current through the tyres should be considered as a potential hazard. If any persons suspect there is a danger of a tyre explosion, as in the case of the mobile crane contacting overhead electric lines, then the procedure should include:

parking the crane in an isolation zone, with a minimum 300 metre radius removing all persons from the area, and not allowing access to the isolation zone for 24

hours, and alerting fire fighting services.


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APPENDIX D – REQUIREMENTS FOR THE TRANSPORTATION OF HIGH LOADS

All jurisdictions have special requirements for the transportation of high loads above 4.3 or 4.6 metres on public roads and require a gazette notice and/or permit for oversized or over-mass vehicles prior to transportation. For example, the New South Wales Road and Traffic Authority (RTA) requires a Load Carrying Permit for oversized or over-mass vehicles over 4.6 metres in height. If vehicles exceed 5.0 metres in laden height they must be accompanied by an Over Height Clearance Authority letter from each Electricity Supply Authority affected on the route to be travelled before a Load Carrying Permit will be issued by the RTA. A pilot or escort operation may be required in some circumstances with two-way communication between the escorted vehicle and the pilot and escort vehicles required. Permit and operating conditions may include: use of warning devices such as signs, flashing lights and flags; speed restrictions; and time and route restrictions for specific travel zones.

Written approval from other authorities may also be required. Some contacts for your state or territory are provided below: Rail or Tram Authority if travelling across rail or tram lines with overhead electric lines Electricity Supply Authority if travelling under or near high voltage electric lines Telecommunication Authority if travelling under communication cables, and Police Services if a police permit or police escort is required.

The National Permit Offices in each jurisdiction listed below can also provide further information.Jurisdiction Unit Name Contact

Australian Capital Territory

Roads ACT,Heavy Vehicle Permits Office

Ph: (02) 6207 6565Fax: (02) 6207 6872Web: http://www.tams.act.gov.au

New South Wales

Road and Traffic Authority,Special Permits Unit

Ph: 1300 656 371Fax: 1300 361 570Web: http://www.rta.nsw.gov.au

Northern Territory

Department of Lands and Planning,Motor Vehicle Registry,Permits Section

Ph: (08) 8999 3148Fax: (08) 8941 0260Web: http://www.mvr.nt.gov.au

Queensland Department of Transport and Main Roads, Queensland Transport, Vehicle Engineering & Access Unit

Ph: (07) 3253 4452Fax: (07) 3253 4607Web: http://www.tmr.qld.gov.au

South Australia Dept. for Transport, Energy & Infrastructure,Vehicle Permits Section

Ph: 1300 882 249Fax: (08) 8348 9551Web: http://www.transport.sa.gov.au

Tasmania Dept. of Infrastructure, Energy & Resources,Land Transport Safety Division,Permits Officer

Ph: (03) 6233 5214Fax: (03) 6233 5210Web: http://www.transport.tas.gov.au

Victoria Vic Roads Permit Group Ph: (03) 9881 8852 or 13 11 17Fax: (03) 9881 8854Web: http://www.vicroads.vic.gov.au

Western Australia

Main Roads,Heavy Vehicle Operations

Ph: (08) 9311 8450Fax: (08) 9311 8455Web: http://www.mainroads.wa.gov.au


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http://www.mainroads.wa.gov.au/

http://www.vicroads.vic.gov.au/

http://www.transport.tas.gov.au/

http://www.transport.sa.gov.au/

http://www.tmr.qld.gov.au/

http://www.mvr.nt.gov.au/

http://www.rta.nsw.gov.au/

http://www.tams.act.gov.au/

APPENDIX E – OTHER RELEVANT INFORMATION

Australian/New Zealand Standards

AS/NZS1768: Lightning Protection. AS: 2550.5 Cranes, hoist and winches - Safe Use Part 5: Mobile cranes AS: 4024.1 Safeguarding machinery AS/NZS: 4576 Guidelines for Scaffolding AS: 61508 Functional safety of electrical/electronic/programmable electronic safety-

related systems

International Standards

ISO 13849-1:2006 Safety of machinery – Safety related parts of control systems – Part 1: General principles for design

National Electricity Network Safety Guidelines

ENA NENS 04-2006 National guidelines for safe approach distances to electrical and mechanical apparatus – Energy Networks Association.


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Working Overhead Underground Electric Lines

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