Which wire size is NOT permissible for small appliance circuits?

The correct response highlights that No. 14 wire is not permissible for small appliance circuits according to the National Electrical Code (NEC) guidelines. Small appliance circuits are typically required to support a maximum load and are generally needed to handle at least 15 amps.

No. 14 wire is rated for a maximum of 15 amps, which aligns with the minimal requirement for such circuits. However, for small appliance circuits, it’s advisable to use wire sizes that can better manage potential overloads and provide a margin of safety.

In most installations, No. 12 wire is commonly used because it can handle up to 20 amps, ensuring that the circuit can accommodate potential increases in load without risk of overheating or tripping the circuit breaker.

While No. 10 and No. 16 wires can technically fit within specific circuit regulations, they aren't suitable for general small appliance use. No. 10 is generally used for higher amperages, and No. 16 is too small and also not typical for household circuits. Thus, the choice of wire must not only adhere to the minimum ampacity requirements but also ensure safety, which is why larger gauge wires like No. 10 are typically not used for small appliance circuits.