What type of devices are commonly used for overfill prevention?

The correct answer highlights that flow shut-off devices, alarms, and vent-restriction devices are essential components for preventing overfilling in underground storage tank (UST) systems.

Flow shut-off devices play a critical role by automatically stopping the flow of fuel when the tank reaches a predetermined level, effectively preventing overflow. Alarms are crucial for alerting operators to rising fluid levels, signaling that immediate action is required to prevent spillage. Vent-restriction devices also contribute to overfill prevention by controlling the venting of vapors during filling, ensuring that the tank does not overfill due to pressure imbalances or excessive rates of fuel being added.

These components work together to create a robust system for managing product levels within the tank, ensuring both regulatory compliance and environmental protection by minimizing the risks associated with overfilling. Understanding the functionality and interdependence of these devices is vital for anyone involved in UST operations, as they are integral to effective spill prevention strategies.