Which statement best describes what constitutes a valid movement authority?

Which statement best describes what constitutes a valid movement authority?

• A. A loud whistle from the engineer.
• B. Verbal permission from the yardmaster.
• C. A green flag from a supervisor.
• D. A valid signal or track authority that authorizes movement.

Answer: (D)

Movement authority is the explicit permission to occupy or move on a specific section of track, issued by the controlling railroad authority and usable by the crew. The best description is that a valid signal or track authority authorizes movement. Signals provide the official indication to proceed, slow, or stop, and track authorities—like track warrants, block clearances, or interlocking orders—give written or electronic authorization for a particular route. A loud whistle is only a warning and does not grant permission to proceed. Verbal permission, unless it is backed by an official written or electronic record, isn’t formal authorization in most operating rules, and a green flag from a supervisor isn’t a recognized, stand-alone form of movement authority. So, only a current, valid signal or track authority truly authorizes movement.

Movement authority is the explicit permission to occupy or move on a specific section of track, issued by the controlling railroad authority and usable by the crew. The best description is that a valid signal or track authority authorizes movement. Signals provide the official indication to proceed, slow, or stop, and track authorities—like track warrants, block clearances, or interlocking orders—give written or electronic authorization for a particular route. A loud whistle is only a warning and does not grant permission to proceed. Verbal permission, unless it is backed by an official written or electronic record, isn’t formal authorization in most operating rules, and a green flag from a supervisor isn’t a recognized, stand-alone form of movement authority. So, only a current, valid signal or track authority truly authorizes movement.