What is the purpose of hand signals in rail switching?

The purpose of hand signals in rail switching is primarily to communicate instructions to crew members when voice communication may not be feasible. This is crucial in a dynamic rail environment where noise levels can be high, or where distances between crew members may impede effective verbal communication. Hand signals serve as a standardized method of conveying commands clearly and efficiently, ensuring that all personnel involved in the switching operation understand the actions required to maintain safety and efficiency during maneuvers. This non-verbal communication is essential for coordination and can prevent misunderstandings that could lead to accidents or delays.

The other options do not encompass the primary function of hand signals within the context of rail switching. For example, they are not designed to provide information to train passengers, indicate train schedules, or mark starting points for races. Each of these scenarios involves different forms of communication or marking that do not relate to the operational safety and efficiency needed in rail switching procedures.