What is required when a track switch is being operated within an interlocking?

• A. You may operate it freely if it seems safe.
• B. Movement must be governed by interlocking signals and routing, with no deviation unless authorized.
• C. Interlocking signals do not apply to the switch.
• D. Only a supervisor can approve.

Answer: (B)

Within an interlocking, a track switch must be moved only under the control of the interlocking signals and the assigned routing, with no deviation unless properly authorized. This coordination ensures that the switch position is part of a safe, protected route, preventing conflicts with other movements and avoiding wrongful or unsafe routing. The interlocking logic makes sure that signals, switch positions, and routing all align before a movement is permitted, so you can’t operate a switch freely or ignore the signals.

Deviating from the interlocking’s authority can create conflicting routes or derailments, which is why the other ideas don’t fit. Signals apply to the switch, not just a supervisor’s approval, and the standard practice is to follow the interlocking control rather than exercising independent discretion.