What is the requirement when a block signal indicates reduced speed due to yard limits?

When a block signal indicates reduced speed due to yard limits, the requirement is to observe restricted speed. This means that the train must operate at a speed that allows for stopping within half the distance of visibility ahead, or within the distance prescribed by the signal indication. This is particularly important in yard areas where the potential for encountering other trains, equipment, or obstructions is higher.

Observing restricted speed provides a crucial safety margin, allowing the train crew to react effectively to any unforeseen circumstances that may arise in the yard limits. It ensures that the train can stop safely if necessary, promoting safety in areas where the likelihood of personnel and equipment being present is increased.

The other options do not directly address the requirement set by the block signal when it indicates reduced speed due to yard limits. While local regulations may influence train operations, they do not replace the requirement for restricted speed under these specific conditions. Notification of crew members and the use of horns, while important in certain situations, do not fulfill the requirement related to speed in this context.