Scope, design information and safe preparation

Good 2391 practice starts before a single lead is connected.

Preparation checklist
• Confirm supply type, earthing arrangement, nominal voltage and protective devices.
• Obtain drawings, circuit schedules and previous certificates where available.
• Agree extent and limitations with the client.
• Plan isolation points, access, sequencing and any disruption to the occupier.

Strong answer structure
1) Gather information.
2) Define scope and limitations.
3) Risk assess the work.
4) Prepare instruments and safe isolation.
5) Start inspection before testing.