18th Edition practice questions (BS 7671) with answers
15 free practice questions on the topics that come up again and again in the 18th Edition (C&G 2382) exam and on site — disconnection times, RCDs, insulation resistance, Part 7 special locations and EICR coding. Tap each one to see the answer and the regulation behind it.
Practice questions
- 0.2 s
- 0.4 s
- 1 s
- 5 s
Show answer
Answer: B — 0.4 s
Table 41.1 gives 0.4 s for TN systems at 230 V (Regulation 411.3.2.2). This applies to final circuits up to 63 A with socket-outlets and up to 32 A supplying only fixed equipment.
- 0.2 s
- 0.4 s
- 1 s
- 5 s
Show answer
Answer: A — 0.2 s
Table 41.1 gives 0.2 s for TT systems at 230 V. TT disconnection times are shorter because the earth fault path relies on the installation earth electrode.
- 0.4 s
- 1 s
- 5 s
- 10 s
Show answer
Answer: C — 5 s
5 s is permitted for distribution circuits and for final circuits above the ratings covered by Table 41.1 in TN systems (Regulation 411.3.2.3). For TT systems it is 1 s (411.3.2.4).
- 10 mA
- 30 mA
- 100 mA
- 300 mA
Show answer
Answer: B — 30 mA
Regulation 411.3.3 requires additional protection by a 30 mA RCD for socket-outlets with a rated current not exceeding 32 A (with limited exceptions, which must be documented).
- 0.25 MΩ
- 0.5 MΩ
- 1.0 MΩ
- 2.0 MΩ
Show answer
Answer: C — 1.0 MΩ
Table 64 requires a test voltage of 500 V DC and a minimum of 1.0 MΩ for circuits up to and including 500 V (other than SELV/PELV).
- 250 V DC, 0.5 MΩ
- 500 V DC, 1.0 MΩ
- 250 V DC, 1.0 MΩ
- 100 V DC, 0.25 MΩ
Show answer
Answer: A — 250 V DC, 0.5 MΩ
Table 64: SELV and PELV circuits are tested at 250 V DC with a minimum of 0.5 MΩ.
- Section 701
- Section 702
- Section 704
- Section 722
Show answer
Answer: A — Section 701
Section 701 covers locations containing a bath or shower. 702 is swimming pools, 704 construction sites and 722 electric vehicle charging installations.
- Section 705
- Section 712
- Section 722
- Section 753
Show answer
Answer: C — Section 722
Section 722. 705 is agricultural and horticultural premises, 712 solar PV and 753 heating cables and embedded heating systems.
- Insulation resistance
- Polarity
- Continuity of protective conductors
- Earth fault loop impedance
Show answer
Answer: C — Continuity of protective conductors
Continuity of protective conductors (including main and supplementary bonding) is tested first, followed by continuity of ring final circuit conductors, then insulation resistance and polarity. Earth fault loop impedance is a live test.
- 0.35 Ω
- 0.69 Ω
- 1.38 Ω
- 0.17 Ω
Show answer
Answer: A — 0.35 Ω
After cross-connecting line and cpc, each socket should read approximately (r1 + r2) ÷ 4 = (0.52 + 0.86) ÷ 4 ≈ 0.35 Ω. Readings should be broadly the same all round the ring.
- C1
- C2
- C3
- FI
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Answer: A — C1
C1 is danger present. C2 is potentially dangerous (urgent remedial action required), C3 is improvement recommended and FI means further investigation required without delay.
- Unsatisfactory
- Satisfactory
- Further investigation
- It depends on the number of C3s
Show answer
Answer: B — Satisfactory
Any C1, C2 or FI makes the report unsatisfactory. C3 items alone do not.
- Green
- Green-and-yellow
- Yellow
- Black
Show answer
Answer: B — Green-and-yellow
Table 51: protective conductors are green-and-yellow. This combination must not be used for any other purpose.
- 2.3 A
- 23 A
- 230 A
- 0.43 A
Show answer
Answer: B — 23 A
Ohm's law: I = V ÷ R = 230 ÷ 10 = 23 A.
- Every year
- At least every 5 years
- Every 10 years
- Only on change of tenant
Show answer
Answer: B — At least every 5 years
The Electrical Safety Standards in the Private Rented Sector (England) Regulations 2020 require inspection and testing at least every 5 years (or sooner if the report says so).
What the 18th Edition exam covers
The City & Guilds 2382-22 exam tests your ability to find and apply the requirements of BS 7671. Questions are spread across the structure of the book:
- Part 1–2: scope, object, fundamental principles and definitions.
- Part 3: assessment of general characteristics.
- Part 4: protection for safety — electric shock (Chapter 41), thermal effects, overcurrent, voltage disturbances.
- Part 5: selection and erection — wiring systems, protective devices, earthing and bonding.
- Part 6: inspection and testing.
- Part 7: special installations or locations, such as bathrooms, construction sites and EV charging.
- Appendices: including current-carrying capacity and voltage drop tables.
Tips for passing
- Learn the layout, not the words. Know that Chapter 41 is shock protection, Chapter 52 wiring systems, Chapter 64 initial verification, and the 700 numbers are special locations.
- Use the index and definitions. Many questions turn on an exact definition from Part 2.
- Practise under time pressure. Timed practice papers build the speed you need to find answers.
- Read every option. Distractors are often a regulation that applies to a different system (TN vs TT) or circuit type.
Full 18th Edition practice quizzes, timed exam simulators, 2391 inspection and testing questions, Level 2 and Level 3 8202 — with feedback on every answer and a study plan based on your weak areas. Free to use.
Frequently asked questions
What is the 18th Edition exam?
It is the City & Guilds 2382-22 qualification in the Requirements for Electrical Installations (BS 7671:2018). It is an open-book, multiple-choice exam that tests whether you can find and apply regulations in BS 7671, not whether you can memorise them.
Is the 18th Edition exam open book?
Yes. You can take the BS 7671 book into the exam. The skill being tested is navigating it quickly — knowing which Part, Chapter or Section to go to — so practise with the book open, exactly as you will in the exam.
Which amendment of BS 7671 should I study?
Always study the current amendment of BS 7671 that your exam is set against. Your training provider will confirm which edition and amendment applies to your exam date. iZapp content is aligned to BS 7671:2018+A4:2026.
How many practice questions does iZapp have?
iZapp has over 4,700 practice questions across Level 2, Level 3 8202, the 18th Edition, 2391 inspection and testing and EV charging, each with feedback, plus over 1,200 flashcards.
Are these questions the real exam questions?
No. They are original practice questions written to test the same knowledge. Real exam papers are confidential and should never be shared.
Last updated 2026-10-14. Regulation numbers refer to BS 7671:2018 as amended. Always check against the current amendment.