Conduit Bushings

Bushings are typically required on PVC conduit. While PVC conduit does not have sharp edges like metal conduit, the NEC often mandates bushings or other protective fittings to ensure wire insulation is not damaged during pulling or operation. Some PVC conduit fittings come with built-in smooth edges or integral bushings, which may meet the code requirement. Always consult NEC Section 352 and local regulations to determine if a separate bushing is required for your specific installation.

Bushings are required on EMT conduit in certain situations. Specifically, NEC Section 344.46 states that bushings must be used on EMT where conductors 4 AWG or larger are present to protect against abrasion at the ends of the conduit. For smaller conductors, EMT connectors with built-in smooth edges or integral bushings may meet the requirement. Bushings are particularly necessary at terminations or points where cables are pulled, ensuring the insulation of conductors is not damaged.

For EMT, bushings are required when conductors 4 AWG or larger are installed, as specified in NEC 344.46 and 300.4(F), to prevent damage at the conduit ends. Similarly, RMC and IMC must have bushings in these cases, and grounding bushings may also be needed for bonding. For PVC conduit, NEC 352.46 mandates bushings at terminations to protect conductors, even though PVC lacks sharp edges. Flexible metal conduit (FMC) typically does not require separate bushings, but its fittings must provide equivalent protection. Additionally, connectors or fittings with integral bushings are often used in other conduit systems to meet code requirements. NEC 300.4(F) further emphasizes that protection is required wherever conductors enter enclosures, fittings, or conduit ends, ensuring the safety and integrity of the installation.

The NEC rule for the installation of bushings on rigid metal conduit (RMC) is outlined in NEC 344.46, which mandates that bushings must be installed where conductors 4 AWG or larger enter or exit the conduit to protect the conductor insulation from damage due to sharp edges. Additionally, if the conduit system requires grounding or bonding, grounding bushings may be required, as specified in NEC 250.96 and 250.102. These bushings often include a grounding lug to ensure electrical continuity. The bushings must be listed and appropriately sized for the conduit and conductor being used, and they must comply with the manufacturer’s specifications and code requirements to ensure proper protection and safety.