What type of conduit is commonly used for underground installations of electrical systems?

PVC conduit is commonly used for underground installations of electrical systems due to its inherent properties that make it suitable for such environments. One of the main advantages of PVC conduit is its resistance to moisture and corrosion, which is essential for installations buried underground, where it could be exposed to water or other environmental factors that can degrade metal conduits.

Furthermore, PVC is lightweight and easy to work with, allowing for straightforward installation without the need for additional specialized tools. It also provides good electrical insulation, which helps to protect the conductors inside from potential grounding issues that could arise in damp conditions. These characteristics make PVC conduit a preferred choice for many electrical applications beneath the ground, ensuring both durability and reliability in electrical installations.