What indicates that a train is approaching with flashing green signals?

The presence of flashing green signals indicates that a train is operating in specific conditions, particularly in Maintenance of Way (MCS) and Automatic Train Control (MATC) modes. These signals serve as a clear indication to engineers and operators that the train is approaching while under controlled circumstances, meaning that it is operating safely and within prescribed limits.

When a train is in MCS and MATC, it signifies that automated systems are managing train operations, which enhances safety and efficiency. This mode is usually employed to facilitate work on the railway or to navigate through areas where the train's operations are being closely monitored. In this situation, operators can expect the train to be functioning normally, aligning with the technical standards set for safe train movements.

This understanding is crucial for ensuring that personnel take appropriate precautions while navigating around train tracks, especially under conditions that could indicate that maintenance or unusual circumstances are being managed.