Which of the following materials does NOT fall under the NEC's raceway definition?

The National Electrical Code (NEC) defines raceways as channels for holding wires, cables, or busbars. By their definition, raceways typically include conduits, duct systems, and certain types of electrical enclosures designed to contain electrical conductors.

Cables consist of multiple conductors insulated and bundled together, which means they are complete assembly units rather than conduits for separate wires or busbars. Likewise, busbars are metal bars that conduct electricity within a switchboard, panel board, or other electrical apparatus and do not function as a pathway for conductors. Pipes, typically understood within the context of raceways, are indeed considered part of this category when they are used to enclose wires or cables.

Wire itself refers to individual conductors that do not have any structure to contain them like a raceway. Thus, it is essential to recognize that cables, busbars, and pipes each have characteristics that align with how they are used under the NEC definitions. However, since cables do not serve as a raceway, the understanding that they are distinct from raceways becomes clear, marking them as not falling under that specific definition.