California ICC UST Inspector Practice Exam 2025 - Free ICC UST Inspector Practice Questions and Study Guide

The correct choice is based on a clear understanding of what constitutes an approved overfill prevention system within the context of underground storage tank (UST) regulations. Overfill prevention systems are designed to prevent the overfilling of storage tanks, which can lead to spills and environmental hazards.

Automatic shutoff devices function to automatically cease flow to a tank when a predetermined level is reached, effectively preventing overfilling. Overfill alarms serve as auditory or visual alerts to notify operators when the tank is reaching its maximum capacity, allowing for timely intervention. Flapper valves, often used in conjunction with spill containers, facilitate a controlled release and prevent product from spilling over during filling operations.

Spill containers, however, serve a different purpose. They are designed to capture any spilled product that may escape during the filling process but do not actively prevent overfilling themselves. Hence, while they are important for spill management and environmental protection, they do not qualify as an overfill prevention system. This distinction is what makes spill containers the incorrect answer in the context of identifying an approved overfill prevention system.