According to the NEC®, which conduit is required to have bushings?

The requirement for bushings in conduits is outlined in the National Electrical Code (NEC). These bushings are used to protect the wire insulation from damage at the ends of the conduit where wires enter or exit. In specific instances, such as with conduits made from certain materials or designed for particular applications, the NEC mandates the use of bushings to ensure safety and compliance.

In this case, the correct answer indicates that Conduit Y has a specific requirement for bushings, likely because it is made from a material prone to sharp edges that could damage the insulation of the conductors, or it is installed in a manner that exposes the conductors to potential abrasion. Understanding why certain conduits require protective components emphasizes the importance of following safety standards in electrical installations.

Conduit X and Conduit Z may not have the same requirements due to their material composition or the typical applications they are intended for. Some conduits might already have integral protection features or might be used in configurations that minimize risk. This differentiation in requirements is critical for ensuring electrical installations are safe and effective, aligned with NEC standards.