How to plan work near power lines with an aerial work platform

Work near overhead power lines must be organised well before the aerial work platform arrives on site. The assessment should begin when the operation is first planned, before the machine is selected, its position is determined or the operating procedure is approved.

Direct contact with an electrical conductor is one of the most obvious hazards, but it is not the only one. Electrical arcing or flashover may occur without physical contact if the boom, platform, operator, tools or materials enter a hazardous area.

Your preparation must therefore cover every stage of the operation. This includes vehicle access, positioning, stabilisation, platform movements, work at height and the complete return of the machine to its transport configuration.

The first step is to establish whether the operation will take place near an electrical installation or directly on the installation itself. The applicable clearances, qualifications and working procedures depend on this distinction.

Construction, operation and maintenance activities performed on electricity distribution infrastructure are governed by a separate framework.

Inspect the complete site before deciding where the vehicle will be positioned. The survey must include the working area, the vehicle access route, the intended parking position and the entire volume through which the boom may move.

A power line may be partially concealed by a tree, building, street furniture or another item of equipment. Conductors may also be located behind the vehicle, beside the machine or below the level eventually reached by the platform.

The network operator or the person responsible for the installation should provide the technical information required for the assessment. This information will help you understand the layout of the network and prepare the movements of the aerial platform.

The condition, colour or apparent age of a power line does not indicate whether it is energised. Unless its electrical status has been confirmed by the person responsible for the network, it must be treated as live.

Where de-energisation is included in the selected safety measures, obtain formal confirmation before allowing the work to begin. The team must never rely on an assumption that the line has been disconnected.

Do not deploy the aerial platform when the conductor, voltage range or applicable working conditions cannot be identified. Report the uncertainty to the site manager and wait until the missing information has been provided.

For non-electrical work carried out near bare, energised overhead power lines, the French Order of 5 July 2024 establishes two general safety distances:

• Less than or equal to 50,000 V: 3 metres
• Greater than 50,000 V and less than or equal to 500,000 V: 5 metres

These distances apply to the workers and to every element involved in the operation. The vehicle, boom, platform, tools, loads and handled materials must all remain outside the relevant safety distance.

The clearance must be measured from the part of the machine, load or equipment that could come closest to the conductor. Measuring only from the vehicle or from the operator’s position may give an incomplete view of the risk.

These distances do not establish the conditions for performing live electrical work. Work on an energised installation remains subject to the approach distances, techniques and procedures defined for the specific operation.

Movement must also be included in the assessment. Wind, changes in conductor sag, platform oscillation or the swinging of a material may reduce the clearance initially observed from ground level.

The intended final position of the platform is not enough to evaluate the electrical risk. You must consider the complete volume through which the boom, platform and equipment may travel.

The working envelope includes elevation, horizontal outreach, turret rotation and platform orientation. It must also take account of poles, cables, tools and components that may extend beyond the platform guardrails.

The required clearance must remain controlled throughout every movement. IPAF recommends selecting and positioning the machine so that no part of it can enter the hazardous area at any stage of the operation.

Where the site layout allows, approach the work area in two phases. First raise the platform to the required height in a clear space, then move towards the final position using short and controlled movements.

The closest available position is not necessarily the safest place for the carrier vehicle. Select a location that allows the operator to reach the work area without moving the boom, platform or tools through a dangerous volume.

Greater outreach may allow the vehicle to remain farther away from the line or help the boom pass over an obstacle. However, it also increases the area swept by the machine during rotation and extension.

The maximum outreach stated in the technical specifications must therefore be interpreted using the manufacturer’s working envelope diagram. It should be considered in relation to the exact position and configuration planned for the site.

Where conditions permit, positioning the vehicle perpendicular to the line may make the clearance easier to observe. This option remains dependent on the available space, ground conditions, stabiliser deployment and the limits specified by the manufacturer.

A non-insulated aerial work platform may be suitable for work carried out away from the network when the risk assessment confirms that the required distances can be maintained throughout the operation.

For live working, select an insulated aerial work platform that is electrically rated for the intended task. Its configuration and conditions of use must remain compatible with the procedures established for the installation.

A composite platform does not, by itself, make the whole machine insulated. The level of electrical protection depends on several elements, including the insulating sections of the boom, any platform liners, the machine configuration and its electrical markings.

The electrical class must be visible and clearly identifiable on the equipment. The operator should also be able to confirm that the rating corresponds to the voltage and type of work involved.

Working height and outreach remain relevant selection criteria, but they should not be considered separately. Platform capacity, carried load, stabilisation requirements and the working envelope must be included in the decision.

The most suitable machine is not automatically the one with the greatest working height. It is the aerial platform that allows the team to reach the work area from a stable and controlled position.

Before deploying the stabilisers, make sure that the supporting surface can withstand the forces transmitted by the vehicle. Examine the site for slopes, weak verges, trenches, backfilled areas, manholes and slabs with unknown load-bearing capacity.

Boom movement changes the position of the machine’s centre of gravity. Poor levelling, insufficient stabiliser support or ground subsidence can compromise stability and alter the path followed by the platform.

Comply with the slope and inclination limits stated in the manufacturer’s operating instructions. Use suitable spreader pads when required by the ground conditions.

Never place a stabiliser on a cover, slab or underground structure unless its resistance has been confirmed. A surface that appears solid may conceal a void or structure unable to support the applied load.

Weather may change the clearances and operating conditions during the work. It should be reviewed before the operation begins and monitored for as long as the platform remains deployed.

Wind can move the conductors, cause the platform to sway and make tools or materials more difficult to control. Temperature variations may change conductor sag and therefore alter the actual height of the line above the ground.

Do not wait until the manufacturer’s maximum wind-speed limit is reached when the clearance can no longer be controlled. Work should also stop when visibility or communication has deteriorated.

The assessment must remain dynamic. Review it whenever the weather, site configuration or working conditions change.

The complete operating area must be clearly defined and secured. Barriers, traffic restrictions and designated routes should protect both the work team and other road users.

A vehicle or pedestrian entering the area unexpectedly may force the operator to stop or change a movement. This disruption can increase the risks of electrical contact, collision, crushing or falling objects.

Where equipment passing beneath a power line could breach the required clearance, the site organisation must prevent that movement. Appropriate height-control or access-restriction measures may also be required.

Clearly mark every area that vehicles, equipment and pedestrians must not enter. The exclusion zone should cover the space beneath the platform as well as the entire area swept by the boom.

Complete all inspections required by the manufacturer before every operation. Check the controls, emergency stops, lower control station, emergency lowering system, stabilisers, hydraulic components, boom and platform.

Additional checks are required for an insulated aerial work platform. These include:

• the validity of the electrical test certificate;
• the validity and suitability of the boom’s insulation rating;
• the legibility of the electrical and safety markings;
• the correct operation of the safety devices.

Machine familiarisation must cover these points before the aerial platform is put into service. The operator and ground-based person should know where the relevant markings and controls are located.

Insulating surfaces must remain clean and free from cracks, impact damage or contamination that could affect their properties. Dirt, moisture and other deposits may reduce the protection expected from the equipment.

A visual check does not replace the periodic tests specified by the manufacturer or required by the applicable procedures. When a defect or abnormality is found, remove the machine from service until it has been assessed by a competent person.

Where the required clearances need continuous supervision, the employer must appoint an electrical safety observer. Their task is to prevent workers and equipment from crossing the boundary of the authorised working area.

The ground-based operator and the electrical safety observer may be the same individual, but the two responsibilities must remain clearly distinguished. Anyone monitoring the distance from the line must remain focused on that task.

The designated person must understand the working envelope and emergency lowering procedures of the machine. They should also know how to stop platform movements from the lower control station.

Agree on a communication method before raising the platform. Where voice communication or hand signals are unreliable, provide radios and use instructions understood by everyone involved.

Operating an aerial work platform and managing electrical hazards require different types of competence. A person may be trained to operate a MEWP without being authorised to work on an energised electrical installation.

Confirm that the platform operator has received appropriate training and holds the operating authorisation issued by their employer. The ground-based person must also understand the machine and know how to use its emergency systems.

For live electrical work, each person involved must hold the qualifications and authorisations required for the task. They must also have received the instructions applicable to the installation concerned.

The presence of an insulated aerial work platform does not, on its own, authorise live working. The equipment must be incorporated into an approved operating procedure.

Before every operation, make sure that the team understands the working method, required clearances and stop-work conditions. Everyone should also know what to do following electrical contact or flashover.

The rescue procedure must be established before the platform leaves the ground. It should identify who is authorised to use the lower controls and explain how the machine can be stopped or returned to a safe position.

Keep access to the emergency control station clear throughout the operation. The designated person must know the machine model, the available lowering systems and the limitations of each procedure.

IPAF includes the rescue plan and communication arrangements among the elements that should be prepared before work begins. These measures should be adapted to the site rather than treated as a generic formality.

The procedure must also cover electrical contact and flashover. In this situation, the entire machine should be regarded as energised.

Prevent anyone from approaching or touching the vehicle until the network operator has confirmed that the electrical hazard has been removed. Attempting to assist the occupants without this confirmation could expose additional people to danger.

Tyres and tracks do not mean that the aerial work platform is isolated from the ground. Touch voltage may be present on the vehicle, while step voltage may develop in the surrounding area.

Work near a power line cannot be planned on the basis of working height alone. The electrical network, applicable clearances, ground conditions, machine movements, team competence and rescue arrangements must be assessed together.

Only after this assessment has been completed should the aerial work platform be selected. For live working, check that the insulated configuration, electrical class and operating conditions correspond to the approved working method.

At ISOLI, we can help you define your requirements and select an insulated aerial work platform suited to your live electrical work. Our teams examine the access conditions, required working height, outreach and constraints specific to your operations.