CSLB Class B General Contractor's License Practice Exam

Which gas line installed underground can be bent by a certain number per foot?

1. Steel

2. PVC

3. PE

4. Shielded gas line

The correct answer is: PE

The choice of polyethylene (PE) gas line is appropriate here because PE pipes are specifically designed for gas distribution and can be installed underground with certain bending capabilities. These pipes are flexible, allowing for some degree of bending without compromising structural integrity. This flexibility is advantageous for installation in underground applications where the gas line may need to navigate around obstacles. The ability to bend PE gas lines is typically quantified in terms of a specified radius of curvature per foot. This characteristic makes PE a preferred material in many pipeline applications, including natural gas distribution, as it reduces the need for complex fittings and connections that might increase the risk of failure. Other materials like steel are rigid and typically require more careful handling when installed underground to avoid breakage or other structural issues. PVC is not commonly used for gas applications due to its limitations in high-pressure scenarios and temperature sensitivity. Shielded gas lines, while they may have protective features, do not have the same flexibility as PE lines and may not be able to be bent as per the needs of a specific installation. Thus, polyethylene is the most fitting material for the scenario described in the question.