Which device is commonly used to prevent overfill in UST systems?

Which device is commonly used to prevent overfill in UST systems?

• A. Audible Alarm
• B. Drop Tube With An Automatic Shut Off
• C. Vent Restricting Device
• D. Expandable Bladder In Manway

Answer: (B)

In UST systems, preventing overfill is about stopping the incoming fuel at a preset level, not just signaling that you’re close. The drop tube with an automatic shut-off does exactly that: fuel is delivered through a calibrated tube into the tank, and when the line reaches the designated level, an automatic shut-off activates and stops flow. This directly prevents overfill and minimizes spill risk during deliveries. Audible alarms can warn operators but don’t stop the flow, so they don’t prevent overfill on their own. Vent restricting devices relate to vapor emissions, not liquid fill control. An expandable bladder in the manway isn’t a standard or reliable overfill protection method.

In UST systems, preventing overfill is about stopping the incoming fuel at a preset level, not just signaling that you’re close. The drop tube with an automatic shut-off does exactly that: fuel is delivered through a calibrated tube into the tank, and when the line reaches the designated level, an automatic shut-off activates and stops flow. This directly prevents overfill and minimizes spill risk during deliveries.

Audible alarms can warn operators but don’t stop the flow, so they don’t prevent overfill on their own. Vent restricting devices relate to vapor emissions, not liquid fill control. An expandable bladder in the manway isn’t a standard or reliable overfill protection method.