If radio instructions are not understood or radio contact is not maintained, what must the movement do?

• A. Be stopped immediately
• B. Proceed with caution
• C. Notify the dispatcher after 5 minutes
• D. Continue to the next interlocking

Answer: (A)

When radio instructions aren’t understood or radio contact can’t be maintained, the movement must stop immediately. This keeps trains from moving without clear, verified authorization, preventing dangerous misunderstandings or conflicts on the track. The safe course is to stop right away and work to reestablish communication with the dispatcher to obtain proper instructions before resuming. Options like proceeding with caution, delaying notification, or continuing to the next interlocking don’t provide the guaranteed clearance needed, so stopping first is the correct safeguard.