What is a requirement for an overfill prevention system?

• A. Alert the transfer operator when the tank is 90% full by restricting flow
• B. Provide positive shutoff of flow to the tank when filled to 95% capacity
• C. Provide for manual override of the shutoff device if fuel remains in the delivery vehicle
• D. Provide positive shutoff so no fittings on the tank are exposed to product

Answer: (C)

The requirement for an overfill prevention system focuses on safety and operational efficiency during fuel transfers. One crucial aspect of such a system is the ability to provide a manual override of the shutoff device if there is still fuel in the delivery vehicle. This provision ensures that operators can handle situations where fuel may still be in the delivery truck, thus preventing any unnecessary interruptions in the fueling process. If the system automatically shuts off without considering the fuel remaining in the vehicle, it could lead to a potentially inefficient operation, causing delays and inconveniences.

For example, in situations where a truck might have residual fuel in its delivery hoses or tank, the ability to manually override the shutoff allows operators to prevent excessive back pressure or vacuum scenarios, facilitating a smoother operational experience. This consideration reflects an understanding of the complexity involved in fuel handling and the need for practical operational adjustments.