Which size of fuse or circuit breaker would be appropriate to use with a circuit that uses AWG number 14 wiring?

The American Wire Gauge (AWG) system dictates the safe current-carrying capacity (ampacity) of electrical wiring. AWG 14 wire is commonly used in residential wiring and is rated for a maximum safe current of 15 amperes. Using a larger fuse or breaker, such as 20 or 30 amperes, would allow more current to flow than the wire can safely handle. This can cause the wire to overheat, potentially melting the insulation and starting a fire before the breaker ever trips. Therefore, a 15-ampere fuse or breaker perfectly matches the safety limit of AWG 14 wire, protecting the circuit from overheating.