Safe isolation method statement
Safe isolation makes a circuit dead before anyone works on it. HSE guidance HSG85 sets out the sequence, and the method statement records each step for the job.
- Identify the circuit. Find the circuit or equipment from the drawings and labels. Never assume a label is correct.
- Isolate and lock off. Disconnect every source of supply. Lock the isolator or breaker off with a safety lock that has a unique key, and keep the key.
- Post a caution notice. Put a caution notice at the point of isolation, with the name of the person doing the work.
- Prove the tester. Check the voltage indicator on a proving unit. Use a two-pole voltage indicator with fused leads, as HSE guidance GS38 describes.
- Prove dead. Test that every conductor at the point of work is dead. On a three-phase supply, test every phase.
- Prove the tester again. Re-check the voltage indicator on the proving unit before work starts.
Sources: HSE, HSG85 Electricity at work: safe working practices; Electricity at Work Regulations 1989, regulation 12; Electricity at Work Regulations 1989, regulation 13
Work dead, not live
The Electricity at Work Regulations 1989 allow live work only when all three conditions are met. It must be unreasonable for the conductor to be dead, reasonable to work on it live, and suitable precautions must be in place. The method statement records why the work is done dead, or the precautions where it cannot be.
Electrical method statement example
A consumer unit replacement in an occupied home usually follows these steps. The electrical sample sets out a full method statement and risk assessment for this job.
- Survey and plan. Record the existing circuits, the earthing and bonding, and any faults before work starts.
- Agree the power cut. Tell the occupants when the supply goes off, and plan for anything that cannot lose power.
- Isolate safely. Follow the safe isolation sequence above, at the main switch or the supplier's isolator.
- Replace the unit. Remove the old consumer unit, fit the new one and reconnect each circuit to its labelled device.
- Inspect and test. Inspect and test the installation before it is energised, and record the results.
- Energise and hand over. Restore the supply, check each circuit works, label the board and complete the certificate BS 7671 requires.
Hazards and controls
Electric shock and arc flash from live or badly isolated circuits, controlled by isolation, lock-off and proving dead. You work dead wherever it is reasonably practicable. Then the usual site hazards: working at height for containment, manual handling, dust. Controls follow the hierarchy, so isolation and engineering controls come before PPE, not instead of it.
Competence and certification
Electrical work needs a competent person, for example to the current IET Wiring Regulations (18th Edition), and the right certification. The method statement names the competence required and the standard it works to, so a principal contractor can check it at a glance.
FAQ
- Does it include safe isolation?
- Yes. The safe-isolation sequence (isolate, lock off, prove dead) is part of the numbered method, and electric shock is in the risk assessment with the matching controls.
- What is a safe isolation procedure?
- It is the sequence that makes a circuit dead before work starts. You identify the circuit, isolate and lock it off, post a notice, then prove it dead with a voltage indicator that you check before and after.
- Can I prove dead with a multimeter or a volt stick?
- HSE guidance HSG85 does not recommend either for proving dead on low-voltage systems. A multimeter can be set to the wrong function, and a non-contact tester can miss a live conductor. Use a two-pole voltage indicator.
- Is this an electrical method statement template?
- It is more than a template. You describe the installation and the site, and the method statement and risk assessment are written for that work. You can edit the Word file before a competent person signs it off.
- Will it be accepted on site?
- It follows the HSE five steps and the CDM 2015 framing site managers expect. A competent person still has to review and sign it off before use.
- What does it cost?
- Your first document is free. After that, £15 each, three for £35, or ten for £89. No subscription. You can read a full sample before you decide.