When should a train operator be concerned about "creep on" in the brake system?

A train operator should be particularly concerned about "creep on" in the brake system when brakes are applied. "Creep on" refers to a situation where the brakes do not release fully, causing a small amount of braking force to remain even when the operator intends for the train to be in a fully released state. This can lead to unnecessary wear on the braking components, reduced efficiency, and could potentially affect the train's ability to accelerate or stop properly.

When brakes are applied, if there is "creep on," it indicates a malfunction or an issue within the braking system that requires immediate attention to ensure safe operation. Monitoring the braking action during these times is crucial for maintaining the train's performance standards and safety protocols.

In contrast, the other situations outlined do not highlight the same level of concern for "creep on." When a train is stationary or fully released, the brakes should ideally not cause any interference or hold under these conditions. When a train is accelerating, the focus is on the acceleration dynamics rather than brake functionality, making it less relevant when discussing the implications of having "creep on." Thus, recognizing the concern at the moment when brakes are applied is vital for effective train operations.