Plan · Permit · Prove · Walk away if it isn’t safe
Safe Isolation Starts Before You Touch the Board
The hardest part of safe isolation is not always the tester.Sometimes it is the customer asking, “How long will you be?”The manager saying, “Can we keep that bit live?”The lost day’s pay if you walk away.
This site is a practical learning hub for planning, communicating and carrying out safe electrical isolation in the real world.
Explore the 10-point check. Learn the language. Practise the scenarios. Share the near misses.
- 01L1–L2· · ·
- 02L1–L30V ✓ DEAD
- 03L2–L30V ✓ DEAD
- 04L1–Earth0V ✓ DEAD
- 05L2–Earth0V ✓ DEAD
- 06L3–Earth0V ✓ DEAD
- 07L1–Neutral0V ✓ DEAD
- 08L2–Neutral0V ✓ DEAD
- 09L3–Neutral0V ✓ DEAD
- 10N–Earth0V ✓ DEAD
The real job starts before the tools come out
Safe isolation begins at the booking, not the board.
Permission. Expectations. Authority. The decisions that make an isolation safe are mostly made before you arrive with a tester.
By the time you are at the consumer unit, the negotiation should already be done: who has authorised the shutdown, what is allowed to stay live, how long the supply is down, and what happens if a circuit cannot be safely re-energised. Turn up without that and you are isolating under pressure — which is exactly when shortcuts get taken.
- CustomerCan I just finish this meeting?
- Site managerHow long will this take?
- TenantThe freezer is full.
- Business ownerWe can't shut down card payments.
- EngineerI've driven four hours to get here.
Every technical step happens inside a human situation. Pressure changes decisions.
The 10-point check
Ten three-phase voltage checks, proven dead in order.
On a three-phase board you prove dead between every meaningful pair of conductors — phase to phase, phase to earth, phase to neutral, and neutral to earth. The board runs the full sequence so you can see the order and the logic before you ever pick up a probe.
Important:These ten tests sit inside the wider procedure — plan, permit, identify, isolate, lock off, prove, test, re-prove. The ten checks are not the whole job.
- 01L1–L2· · ·
- 02L1–L30V ✓ DEAD
- 03L2–L30V ✓ DEAD
- 04L1–Earth0V ✓ DEAD
- 05L2–Earth0V ✓ DEAD
- 06L3–Earth0V ✓ DEAD
- 07L1–Neutral0V ✓ DEAD
- 08L2–Neutral0V ✓ DEAD
- 09L3–Neutral0V ✓ DEAD
- 10N–Earth0V ✓ DEAD
Authority
A learning resource, not a replacement for official guidance.
- IET
- HSE
- Electrical Safety First
- NAPIT
- NICEIC
- BS 7671
- Electricity at Work Regs
- GS38
- HSG85
- IET On-Site Guide
Forum · Near misses
A refused isolation is a safety signal, not just a scheduling problem.
If the worker loses money every time they choose safety, the system is quietly rewarding risk.
The safest electrician is not the one who can work around every obstacle. It is the one who sees the pressure coming early enough to control it.