What is the main difference between Type NM and Type UF cable?

The main difference between Type NM (Non-Metallic) and Type UF (Underground Feeder) cable lies in their construction and intended applications. Type NM cable is specifically designed for indoor installations, making it suitable for residential wiring within buildings, where the environment is controlled and not subject to moisture or direct exposure to the elements.

On the other hand, Type UF cable is rated for underground and outdoor use. It features a more robust and moisture-resistant construction, allowing it to be buried underground and exposed to outdoor conditions without compromising safety. This makes UF cable ideal for feeding power to outdoor fixtures, outbuildings, or underground installations.

The distinction in intended use between these two types of cables is critical for ensuring compliance with electrical codes and for the safety and longevity of electrical installations.