In addition to coated steel pipe, which material does VGS use for its gas mains?

The use of high-density polyethylene (HDPE) for gas mains is significant due to its excellent properties that make it suitable for this application. HDPE is lightweight, flexible, and resistant to corrosion, which enhances its durability and longevity. This material is particularly advantageous for underground installations because it can withstand bending and deformation without compromising its integrity. Additionally, HDPE is non-reactive, which prevents any potential chemical interaction with the gas it carries, ensuring safe transport.

In the context of pipeline materials, while other materials like copper and fiberglass might be used in various applications, they are not as prevalent in the construction of gas mains compared to coated steel and HDPE. PVC is generally not suitable for gas mains due to its susceptibility to degradation from UV exposure and its inability to handle high-pressure situations associated with gas transport. Thus, high-density polyethylene emerges as the correct answer, reflecting its established use in the industry for gas infrastructure.