If a train passes an approach signal requiring it to be prepared to stop at the next signal, where must the stop be made?

When a train passes an approach signal that requires it to be prepared to stop at the next signal, it is critical that the stop is made before passing the block signal that indicates a stop is required. This ensures the safety of the train and any trackside operations. By stopping before the block signal, the train can adhere to the signaling system and avoid potential collisions or hazardous situations that could arise from not stopping in time.

This procedure ensures that the train remains within the safe operating limits defined by the signaling system and allows for the appropriate management of train movements on the railway network. Other choices may suggest less precise actions that could compromise safety practices in rail operations. For instance, stopping anywhere along the approach or at the discretion of the engineer would not guarantee that the train is within safe limits. Similarly, stopping at the next station does not address the immediate requirement to stop at the block signal. Therefore, stopping before the block signal that requires the stop is the safest and most compliant action for train operations following a signal indication.