How long in advance must the employee in charge contact the dispatcher before Form B expiration?

The correct answer is one hour in advance. This requirement ensures that there is ample time for the dispatcher to review the situation, confirm the safety of current operations, and make any necessary adjustments before the expiration of Form B. Form B is a critical document that outlines specific work limits for maintenance-of-way activities or similar tasks—allowing for safe control of train movements in areas where work is taking place.

By contacting the dispatcher one hour prior, the employee in charge provides sufficient time for communication and coordination. This helps to address any potential issues or conflicts that could arise from the work being performed while ensuring that all trains are operating safely and according to schedule. Effective communication prior to this timeline minimizes the risk of accidents and assists in maintaining operational efficiency on the railroad.