What indicates that crossing gates are functioning properly?

The indication that crossing gates are functioning properly is when they are fully lowered and not malfunctioning. This state effectively signals to motorists and pedestrians that a train is approaching and that it is unsafe to cross the tracks. Proper functioning of the crossing gates is critical for ensuring safety at rail crossings, as they help to prevent accidents by providing a visual and physical barrier to impede any unauthorized crossing when a train is present.

When the gates are fully lowered, it confirms that the mechanism is operating as intended, providing the necessary warning. Other conditions, such as being partially raised or showing only flashing lights, do not convey the same level of safety and could imply a malfunction or failure in the warning system. Therefore, the scenario where the gates are fully lowered represents the optimal functioning state of the crossing safety system.