Electrical Safety, First Aid and Work Permit Procedures
Domain 10 - Electrical Safety, First Aid and Work Permit Procedures. This domain checks whether you can work on or near live equipment without injury and respond correctly when someone is shocked.
Permit and isolation discipline
- Identify the circuit, isolate it (open the AB switch, remove DO fuses, rack out the breaker), lock and tag, then test with an approved voltage detector before touching anything.
- Apply portable earths on all sides from which supply can come, discharge capacitors, and display Men at work boards. Work starts only after the authorised person issues the permit.
- On completion, withdraw the team, remove earths and tools, cancel the permit, and only then restore supply in the recorded sequence.
- Use PPE: helmet, gloves, safety shoes, full-body harness with double lanyard for pole work, and insulated tools for live-line work.
First aid
- Switch off the supply before touching a casualty; use a dry wooden stick if switching off is impossible.
- If breathing and pulse are absent, start CPR at 30 compressions to 2 breaths, compressing 100–120 times a minute.
- Do not apply water or oil to electrical burns; cover with a clean dry cloth. Keep the casualty warm and get medical help.
Worked example
CPR at 100 compressions per minute with 2 breaths after every 30 compressions: five cycles take about 2 minutes (150 compressions plus 10 breaths). That is why the responder is changed every 2 minutes and the ambulance is called at the start, not after the first cycle.
Traps
- Earthing a line before testing it is dead.
- Removing portable earths before the crew has withdrawn.
- Touching a casualty still in contact with a live conductor.
- Treating a permit as a formality and starting work on a verbal assurance.