What does “non-metallic sheathed cable” refer to in the NEC?

Non-metallic sheathed cable refers to a type of electrical cable that features insulated conductors which are encased in a non-metallic sheath. This design allows for the conductors to be protected from physical damage and moisture while ensuring safety and compliance with electrical codes. Typically used in residential and light commercial wiring, non-metallic sheathed cable, often known as NM cable or Romex, is known for its versatility and ease of installation.

The insulated conductors within this type of cable are usually made of copper or aluminum and are designed to carry electrical current at standard voltages. The non-metallic outer sheath provides an additional layer of protection and is recognized for its flame retardant properties. This makes it suitable for various applications, including indoor wiring where it can be routed through walls, ceilings, and floors.

In contrast, the other options involve either characteristics of cables not fitting the description of non-metallic sheathed cable or applications that are not typically associated with this type of cable. Thus, option B accurately captures the nature of non-metallic sheathed cable as outlined in the National Electrical Code (NEC).