Who should be contacted for instructions when a car is deemed unsafe for movement?

The correct choice is to contact the train dispatcher or yardmaster when a car is deemed unsafe for movement. This is because the train dispatcher or yardmaster is responsible for coordinating train movements and ensuring safety protocols are followed. They have the authority and necessary information to make informed decisions about whether the car can be repaired on-site, moved to a maintenance facility, or if other actions need to be taken.

The yard supervisor, while knowledgeable about yard operations, may not have the overall operational authority to make decisions regarding the movement of potentially unsafe cars. The maintenance crew is typically responsible for repairs but would not be the first point of contact to decide the next steps concerning an unsafe car. The train conductor plays an important role in the operation of the train but is not usually responsible for coordinating movement of equipment in the yard or addressing unsafe conditions. Thus, contacting the train dispatcher or yardmaster ensures that the correct protocols are followed efficiently and safely.