When this template fits
Site managers and electrical contractors setting up the power that keeps a construction site running need this RAMS. It is written for the person installing and maintaining the temporary distribution — the 110V reduced low voltage tools, the transformers, distribution boards and trailing leads that feed the whole site. When the principal contractor wants assurance that your temporary installation meets BS 7375 and is inspected on a regular regime, this is the document that demonstrates it.
What this RAMS includes
- ✓ 7 task-specific hazards scored on a 5×5 matrix (initial → residual)
- ✓ Specific control measures for each hazard, in hierarchy-of-control order
- ✓ A 10-step method statement (sequence of works)
- ✓ PPE, plant/equipment, permits and competence requirements
- ✓ Emergency arrangements and operative briefing / sign-off section
Scope of works
Install/maintain 110V temporary site electrical supplies and distribution.
Sequence of works
- 1Plan and design the temporary electrical supply layout including load schedule, cable routes, transformer and distribution board positions before any installation commences. Confirm all equipment is 110V CTE rated and has current inspection records.
- 2Obtain the necessary permit or authority to connect to the permanent supply intake. Ensure the main incoming supply is isolated, locked off and proved dead before beginning any work on the incoming connection.
- 3Position 110V transformers and distribution boards in designated locations away from pedestrian routes, plant movements and combustible materials. Use mechanical handling aids for heavy equipment.
- 4Install and secure cable routes using overhead cable management systems, buried ducting or ground-level cable ramp protectors as appropriate to prevent damage from traffic and trips. Mark all cable routes on the site plan.
- 5Make all electrical connections with the supply isolated and locked off. Verify correct polarity and earthing continuity on each circuit before energising. Ensure all outlets are RCD protected and distribution boards are clearly labelled.
- 6Test the completed installation using approved test instruments before energising, confirming insulation resistance, earth continuity and correct RCD operation. Record all test results.
- 7Energise the supply in a controlled sequence from the transformer outwards, confirming correct operation at each distribution point. Check for any signs of overheating, fault tripping or abnormal operation.
- 8Brief site operatives on the location of distribution boards, safe use of the temporary supply, the prohibition on unauthorised connections, and the procedure for reporting damaged equipment.
- 9Carry out regular inspections of the temporary supply including visual checks of cables, connectors and boards. Remove and replace defective equipment immediately and maintain inspection records throughout the project.
- 10At project end or when supply is no longer required, isolate and de-energise the full temporary supply in a controlled sequence. Remove all equipment, make safe the incoming supply connection and confirm the site is left electrically safe.
Hazards, risk rating & controls
Risk = likelihood × severity (1–25). Initial is before controls; residual is with controls applied.
Electric shock from live conductors or isolation failure
Who’s at risk: Operatives, Other trades on site
- › Isolate all electrical circuits that could be encountered, apply lock-off/tag-out devices and prove dead using an approved voltage indicator before commencing work. Work on live conductors only where absolutely unavoidable and under a formal permit.
- › Ensure all temporary site supplies operate at 110V CTE (55V to earth) rather than 230V, reducing shock severity.
- › Only trained and competent electricians authorised to work on temporary site supplies should carry out installation, connection and maintenance work.
- › Wear appropriately rated insulating gloves and non-conductive footwear when working near or on electrical equipment.
- › Inspect all cables, plugs, connectors and distribution equipment for damage before use. Remove and quarantine any defective items immediately.
- › Ensure all temporary supply equipment is subject to regular formal inspection and testing by a competent person, with records maintained.
- › Ensure all circuits and outlets on the temporary site supply are protected by appropriately rated residual current devices (RCDs) with maximum 30mA tripping current.
Overloading of temporary electrical supply
Who’s at risk: Operatives, Other trades on site
- › Calculate anticipated electrical loads before installation and size cables, transformers and protection devices accordingly. Document load schedule.
- › Fit appropriately rated MCBs or fuses at all distribution points to prevent overloading of cables and equipment.
- › Implement site rules preventing operatives from making unauthorised connections to temporary supply boards. Distribute a site electrical access permit or allocation process.
Unsafe or damaged cable condition
Who’s at risk: Operatives, Other trades on site
- › Where practicable, route cables overhead on proprietary cable stands/hooks or bury them beneath the surface in protective ducting to avoid traffic routes.
- › Where cables must cross pedestrian or vehicle routes at ground level, use proprietary cable ramp protectors rated for the expected traffic.
- › Mark cable routes clearly on site layout plans and with ground markings or signage to prevent inadvertent damage during excavation or plant movement.
Slips, trips and falls at same level
Who’s at risk: Operatives, Other trades on site
- › Plan cable routes to avoid pedestrian walkways and access routes. Secure cables to walls, fences or overhead supports rather than leaving them trailing on the floor.
- › Position transformers and distribution boards in designated locations out of primary pedestrian and plant routes, secured to prevent toppling.
- › Maintain regular site tidiness inspections to ensure cables have not been displaced into walkways. Correct and record any issues found.
Fire from faulty or incorrectly wired electrical installation
Who’s at risk: Operatives, Other trades on site
- › Ensure all circuits have correctly rated overcurrent protection and RCDs installed to automatically disconnect under fault conditions.
- › Keep transformers and distribution boards clear of combustible materials and stored flammables by a minimum safe distance.
- › Isolate temporary supplies from the main source at end of working day unless a continuous supply is required and a specific risk assessment supports this.
Manual handling — heavy or bulky items
Who’s at risk: Operatives, Other trades on site
- › Use sack trucks, pump trolleys, chain blocks, engine hoists or hydraulic jacks appropriate to the load and space. Ensure rated capacity is not exceeded.
- › Operatives must have received manual handling training covering safe lifting technique, team lifts and use of mechanical aids.
- › Where mechanical aids cannot be used, use a minimum two-person team lift with a defined lift plan, clear communication and a coordinated lift technique.
Fall from height during installation or work at height
Who’s at risk: Operatives, Other trades on site
- › Use a platform step ladder or low-level staging for work above 600 mm. Inspect access equipment before use; do not use chairs, boxes or makeshift platforms.
- › Plan cable routes at ground level or through existing structures where possible to eliminate the need to work at height.
- › Inspect all access equipment before use to confirm it is in good condition, correctly set up and suitable for the task.
PPE
- ✓ Safety footwear (EN ISO 20345)
- ✓ Hi-vis clothing
- ✓ Safety gloves (task-appropriate)
- ✓ Hard hat (EN 397) where overhead risk or site rules require
- ✓ Insulated gloves where live work is unavoidable
- ✓ Safety harness and lanyard where fall arrest is the selected control
Competence
- ✓ Competent electrician; documented safe-isolation competence
- ✓ Site induction completed; CSCS or equivalent where the site requires it
Schemes (CSCS, PASMA, IPAF…) evidence competence; they are not statutory requirements in themselves.
Plant & equipment
- › 110V site transformers and distribution units
- › Weatherproof RCD-protected distribution boards
- › Cable ramps, catenary wire and ducting for lead protection
- › Multifunction installation tester for periodic verification
- › Lockable enclosures and weatherproof connectors
Permits & legislation
What principal contractors usually check
- ✓ That an inspection regime is defined — weekly visual of distribution boards and leads plus three-monthly periodic inspection and test
- ✓ That portable tools and task lighting are fed from 110V centre-tapped-to-earth, not 230V, across the site
- ✓ That cable routing across traffic and pedestrian routes is mechanically protected, not just laid on the ground
- ✓ The document is site-specific — real address, access arrangements and dates, not a generic template
- ✓ Hazards match the actual task and the controls are specific (not “take care” and “use PPE”)
- ✓ Named supervisor and competent person, with operative sign-off space
- ✓ Emergency and rescue arrangements that work for this site
The report builder runs these as pre-submission checks before you download — or run an existing document through the free RAMS pre-submission checker.
Frequently asked questions
Why do construction sites use 110V rather than 230V for tools?
BS 7375 and HSG141 recommend reduced low voltage — 110V centre-tapped-to-earth — for portable tools and task lighting on construction sites. With a CTE system the voltage to earth from either conductor is only 55V, which greatly reduces the severity of any shock if a lead is damaged in the harsh site environment. Damaged leads and water ingress are far more likely on a building site than in a finished installation, so the lower voltage is a practical extra layer of protection. Where 230V genuinely cannot be avoided, it must be protected by a 30 mA RCD and inspected frequently.
How often must the temporary installation be inspected?
The temporary installation should have a weekly visual inspection of distribution boards, transformers and leads, plus a periodic inspection and test typically at three-monthly intervals because the site environment changes constantly. Boards should be labelled with their next due date so anyone can see at a glance whether the regime is current. Any board or lead found damaged is taken out of service and tagged immediately rather than left for the next periodic. The RamsDocs builder lets you record the inspection frequency and the responsible person directly in the document so the regime is part of the RAMS, not a loose schedule.
What regulations apply to temporary site electrics?
Electricity at Work Regulations 1989, Management of Health and Safety at Work Regulations 1999, reg 3 — risk assessment, Regulatory Reform (Fire Safety) Order 2005 are the main ones, alongside Manual Handling Operations Regulations 1992, Work at Height Regulations 2005. The Health and Safety at Work etc. Act 1974 and CDM 2015 apply to all construction work.
Does a method statement need to be site-specific?
Yes — this is the most common reason documents get sent back. Principal contractors reject generic copy-paste RAMS. Your document should name the site, access arrangements, dates, supervisor and any site-specific hazards. The RamsDocs builder fills these in for you and flags what's missing before you download.
Is this template free?
Yes — everything on RamsDocs is free during early access, including building a site-specific version of this RAMS and downloading the PDF. No card required.