The smallest wire size for which overcurrent protection is specified in the Code is ___.

The smallest wire size for which overcurrent protection is specified in the Code is ___.

• A. 14 AWG
• B. 18 AWG
• C. 20 AWG
• D. 16 AWG

Answer: (B)

Overcurrent protection is required to prevent overheating of a conductor when current exceeds its rating. The NEC links conductor size to the protection device that must guard it, so the smallest gauge that the Code explicitly requires protection for in standard branch-circuit wiring is 18 AWG. Conductors smaller than that (like 20 AWG) are typically used in special or low‑voltage applications with different protection rules, so they aren’t covered by the general overcurrent protection requirement in the same way. Hence, 18 AWG is the correct choice.

Overcurrent protection is required to prevent overheating of a conductor when current exceeds its rating. The NEC links conductor size to the protection device that must guard it, so the smallest gauge that the Code explicitly requires protection for in standard branch-circuit wiring is 18 AWG. Conductors smaller than that (like 20 AWG) are typically used in special or low‑voltage applications with different protection rules, so they aren’t covered by the general overcurrent protection requirement in the same way. Hence, 18 AWG is the correct choice.