Which type of conduit is preferred for outdoor installations?

Rigid metal conduit is preferred for outdoor installations primarily due to its durability and protection against environmental factors. This type of conduit is designed to withstand harsh weather conditions, including rain, snow, and temperature fluctuations. Its construction from metal provides resistance to physical damage, making it suitable for areas where exposure to impact or mechanical stress is a concern.

Additionally, rigid metal conduits offer excellent grounding capabilities, which enhances electrical safety when installed outdoors. This grounding feature helps prevent electrical shock and ensures that any fault currents are safely routed to the ground.

While other options like liquidtight flexible metal conduit and non-metallic conduit may have applications in outdoor settings, they typically do not provide the same level of protection and rigidity as rigid metal conduit. Liquidtight flexible metal conduit is generally used for applications needing flexibility in tight spaces, while non-metallic conduit might not offer the same resilience against physical damage outdoors.