In which configuration should a fuel tank be filled to prevent overpressure?

Filling a fuel tank by pressurization does not prevent overpressure; in fact, it can create conditions where overpressure is more likely to occur, especially if the tank is not designed to handle external pressure.

The appropriate method for filling a fuel tank to prevent overpressure is through a pressure relief system. This system is essential for managing any increases in pressure that can occur during the filling process or as temperature changes affect the fuel volume. A pressure relief system allows for the safe release of excess pressure, thereby maintaining the integrity of the tank and preventing potential hazards such as leaks or explosions.

The other options do not adequately ensure safety during the filling process. Continuous flow can lead to improper filling if not monitored closely, while gravity feed can be inefficient in certain situations but may not prevent pressure build-up if the venting is inadequate. Therefore, a pressure relief system is crucial in fuel tank operations to ensure safety and compliance with regulations.