Who must the crew notify before entering a yard with a clearance implicated shipment?

The yardmaster is the individual responsible for overseeing the operations within a yard, which includes managing the movement of cars and locomotives. When a crew is preparing to enter a yard with a clearance implicated shipment, it is essential to communicate with the yardmaster due to their role in maintaining safety and efficiency in the yard. The yardmaster can provide critical information about clearance guidelines, potential hazards, and any specific instructions necessary for handling such shipments. This communication is vital for ensuring that all safety protocols are adhered to and that the entry of the train is managed properly to avoid accidents or damage.

In contrast, while the other positions—such as a yard supervisor, train conductor, or dispatcher—are important in their respective roles, they do not specifically hold the authority or the specific responsibilities related to clearance issues within the yard itself, making the yardmaster the appropriate point of contact in this scenario.