Working Near Overhead Power Lines RAMS: A Practical Guide for UK Contractors
Overhead power lines kill. In the UK, contact with overhead lines remains one of the most common causes of fatal accidents in trades involving plant, scaffolding, roofing and agricultural or construction groundworks. If your work brings people, vehicles or equipment close to overhead lines, you need a robust Risk Assessment and Method Statement (RAMS) before a single machine moves on site.
This guide explains what that RAMS must contain, the legal basis behind it, and the practical controls that actually prevent electrocution.
The Legal Basis
Your risk assessment duty comes from Regulation 3 of the Management of Health and Safety at Work Regulations 1999, which requires you to carry out a suitable and sufficient assessment of risks to employees and others affected by your work.
Where construction activity is involved, CDM 2015 adds a layer: principal designers and principal contractors must consider overhead line risks at the design and pre-construction stage, and the construction phase plan should address them.
The Electricity at Work Regulations 1989 place a specific duty on duty holders to prevent danger from electrical systems — including overhead lines — so far as is reasonably practicable. This is the regulation HSE inspectors will cite if something goes wrong near a line.
Before You Write the RAMS: Gather the Right Information
A RAMS written without site-specific information is not worth the paper it is on. Before writing:
- Identify the line voltage. Contact the Distribution Network Operator (DNO) or National Grid. Voltage determines safe approach distances.
- Confirm ownership and whether the line can be switched off or diverted. Always ask — diversion or de-energisation is the safest outcome.
- Check line height at the point of closest working. Lines sag more in hot weather; never assume the height shown on a drawing is accurate on the day.
- Identify all equipment, vehicles and materials that will work in the vicinity — including crane jibs, tipper bodies, scaffold tubes being carried vertically, and excavator arms.
Safe Approach Distances
HSE guidance (GS6, Avoidance of Danger from Overhead Electric Lines) sets out minimum safe distances. These are not distances you work at — they are the distances at which you must stop, assess and implement controls before going closer:
| Line voltage | Minimum approach distance (uncontrolled) |
|---|---|
| Up to 33 kV (distribution) | 3 metres |
| 132 kV | 5 metres |
| 275 kV | 7 metres |
| 400 kV | 9 metres |
If you do not know the voltage, treat the line as 400 kV until confirmed otherwise.
These distances must appear explicitly in your RAMS, referenced to the specific lines on your site.
The Control Hierarchy in Your Method Statement
The method statement must show you have worked through the hierarchy of controls — not jumped straight to PPE.
1. Eliminate Request de-energisation or permanent diversion from the DNO. This is always the first ask. It takes time to arrange but removes the risk entirely.
2. Substitute / Re-route work Can the task be repositioned so no equipment comes within the safe approach distance? Redesigning the traffic route or crane position is far preferable to managing proximity.
3. Engineering controls — goal posts and barriers Where work must continue near the line, install goal post frames (sometimes called phase barriers or line guards) with a height clearance bar set at a safe height, positioned so that any vehicle that passes through fits safely. Use physical exclusion barriers (Heras fencing or similar) to mark a ground-level exclusion zone beneath and either side of the line. Barriers must prevent drift or accidental encroachment, not just mark a line on a drawing.
4. Administrative controls
- Appoint a designated safety supervisor with sole responsibility for monitoring proximity to the line during each phase of work.
- Implement a permit-to-work system for any task within the supervised zone.
- Brief all operatives at the site induction — include a toolbox talk specific to overhead line risks.
- Establish exclusion zones that are communicated, signed and enforced. No lone working in the zone.
- Agree emergency procedures with the DNO in advance: who to call, how to isolate, how to treat a casualty without touching them or the plant.
5. PPE PPE offers no meaningful protection against high-voltage overhead lines. Do not rely on rubber gloves or insulated footwear as a control near overhead lines — these are not rated for distribution or transmission voltages. PPE has a role (hard hats, hi-vis) but it does not feature as a primary control here.
What the RAMS Document Must Actually Say
A working near overhead power lines RAMS should include:
- Line location, voltage, ownership and confirmed height at the work point
- Confirmed DNO contact details and emergency number
- Specific safe approach distances for this site
- Detailed description of goal posts, barriers and their exact positioning
- Named safety supervisor and their authority to stop work
- Permit-to-work process
- Emergency procedure if contact occurs (including the instruction to keep bystanders at least 15 metres away and not to touch plant or the person until the line is confirmed dead)
- Signatures from the person completing the assessment and the operative or supervisor accepting the method
A Note on "Assumed Safe" Distances
One of the most common errors HSE identifies is contractors assuming a line is safe because it looks far enough away. Distances compress quickly when a tipper body goes up, a crane slews, or scaffold tubes are walked beneath a line end-on. Your RAMS must account for the maximum reach of every item of plant and every activity — not just normal operating positions.
Write the RAMS for the worst credible position, not the intended one.