What type of wire is typically used for common direct burial applications?

The type of wire typically used for common direct burial applications is UF, or Underground Feeder cable. This cable is specifically designed to be buried directly in the ground without the need for conduit. UF cable has a moisture-resistant insulation and is rugged enough to withstand the pressure from soil or other surrounding materials.

This characteristic makes it suitable for outdoor applications, where exposure to the elements can be a concern. It can be used to supply power to outdoor installations such as landscaping lighting, storage sheds, or other outbuildings. The construction of UF cable limits the risk of damage from environmental factors, ensuring its reliability in direct burial situations.

Other types of wire, such as THHN, NM-B, and WL, are not meant for direct burial without additional protective measures and are typically used in dry installations or in conduit. Thus, UF cable stands out as the proper choice for direct burial applications due to its design characteristics and appropriate insulation properties.