Free mock exam

Safe Isolation — C&G 2391 Inspection & Testing Practice

Free topic-focused mock exam: 20 random questions from a pool of 32 on Safe Isolation, drawn from the wider C&G 2391 Inspection & Testing bank. 25-minute timer, 70% to pass, worked explanation on every question. Use this when you've taken the full mock once and want to drill the topics you got wrong.

Questions
20
questions
Time limit
25
min
Pass mark
70%
to pass (14/20)
Bank size
32
question bank

Free · no sign-up · timer can be ignored · retake as many times as you want

Sample questions

  1. 01What is the first step in safe isolation procedure?
    • A.Lock off the supply
    • B.Test that equipment is dead
    • C.Post warning notices
    • D.Identify the source of supply

    Why: The first step is to identify all sources of supply to the circuit or equipment being worked on.

  2. 02What device should be used to verify isolation?
    • A.Approved voltage indicator (AVI)
    • B.A neon screwdriver tester
    • C.A non-contact voltage detector pen
    • D.A standard digital multimeter on the AC range

    Why: An approved voltage indicator (AVI) complying with GS38 should be used to verify isolation.

  3. 03What is the proving unit used for?
    • A.To prove the voltage indicator is working correctly
    • B.To measure the loop impedance at the point of isolation
    • C.To indicate the phase rotation of a three-phase supply
    • D.To discharge any stored energy in the circuit before work

    Why: A proving unit is used to prove that the voltage indicator is working correctly before and after testing.

FAQ

Is the Safe Isolation mock exam free?

Yes — 100% free, no sign-up needed. Questions are pulled at random from a substantial bank, with a worked explanation on every question after you submit.

Can I retake the mock exam?

Yes. Every attempt picks a different random selection and reshuffles the options, so each retake gives you genuinely new questions. No limit on retakes.

Does this count towards the real qualification?

No — this is independent practice material. To gain the actual qualification you need to sit the official assessment through an approved provider.

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