What does Rule 101 permission entail?

Rule 101 permission is a specific directive that pertains to railroad signaling systems. It is designed to ensure safety and clarity for train operators as they navigate through various aspects of the rail network.

The correct answer, which describes a signal displaying a double red over solid lunar white light, indicates that the train must stop, and it is receiving permission to proceed into a section of track that may be under specific conditions. This combination of signals is a critical safety measure, ensuring that operators understand they are in an area requiring heightened caution.

The double red signal typically indicates that the track ahead is occupied or not in a status that allows for train movement without additional procedures, whereas the solid lunar white light can signify that there may be special instructions for the train crew to follow once they receive clear permission.

Understanding Rule 101 permission is essential for those in engineering and operations within railroad systems, as it directly impacts the safety protocols for managing train movements through potentially hazardous areas.