General exam question G0B02
Subelement G0, ELECTRICAL AND RF SAFETY· Group G0B
According to the National Electrical Code, what is the minimum wire size that may be used safely for wiring with a 20-ampere circuit breaker?
- A.AWG number 20
- B.AWG number 16
- C.AWG number 12 (correct answer)
- D.AWG number 8
WhyThe National Electrical Code specifies AWG number 12 as the minimum wire size that may be used safely with a 20-ampere circuit breaker. The National Electrical Code specifies AWG 12 as the minimum wire size safely rated for a 20-ampere branch circuit, thick enough to carry that current without excessive heating, answer C. AWG 20 and 16 are far too thin for 20 amperes and would overheat, and AWG 8 is heavier gauge than the code actually requires as a minimum for this circuit rating, so A, B, and D are wrong.
Published 2026-08-28 · Last updated 2026-08-28 · Question text is verbatim from the 2023-2027 NCVEC Element 3 pool (public domain); the explanation above is original writing, see our methodology.
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