California ICC UST Inspector Practice Exam 2025 – Your All-In-One Guide to Exam Success!

In the context of underground storage tanks (USTs) containing motor vehicle fuel, certain materials are deemed inappropriate due to their inability to withstand the chemical properties of the fuels or their potential for leakage.

PVC (polyvinyl chloride) piping is not permitted for USTs with motor vehicle fuel. The reason for this restriction lies in the fact that PVC can degrade and become brittle when exposed to petroleum products over time. This degradation can lead to cracks and ultimately leaks, which presents significant environmental and safety hazards.

On the other hand, fiberglass-reinforced plastic is a commonly approved material for use with USTs due to its corrosion resistance and structural integrity. Cathodically protected steel is also suitable, as it can mitigate corrosion when properly treated. These materials are designed to handle the requirements of UST applications while ensuring the integrity of the containment.

Thus, recognizing the limitations of certain materials, particularly PVC, in the storage of motor vehicle fuels is essential for maintaining safety and compliance in UST installations.