What common feature do many fuel tanks share to prevent overfilling?

Many fuel tanks incorporate automatic shutoff devices as a key feature to prevent overfilling. These devices are designed to detect when the tank is full and cut off the flow of fuel to prevent spillage and potential hazards associated with overfilling. This feature enhances safety by ensuring that the tank does not exceed its capacity, which can lead to environmental contamination or fire hazards.

Automatic shutoff devices operate through various mechanisms, such as float switches or electronic sensors, which trigger the shutoff when the appropriate level is reached. This contrasts with other methods of monitoring the tank level, which might require manual intervention or serve as less proactive measures. For instance, while manual monitoring can be effective, it relies on the operator's diligence and presence, and can be easily overlooked. Visual indicators, although useful for providing a quick reference, do not actively prevent overfilling unless combined with a responsive action by the operator.

Pressure release valves serve a different purpose, primarily focusing on managing excess pressure within the tank rather than preventing overfilling. Therefore, the automatic shutoff device stands out as a principal feature specifically designed to mitigate the risk of overflow during fuel transfer operations.