What is the specified safety distance between the flagman and lights intended to ensure?

The specified safety distance between the flagman and the lights is primarily intended to ensure safety from passing trains. This concept is critical because flagmen play an essential role in signaling and managing train movements, especially in areas where there may be work or hazards present on or near the tracks. By maintaining a safe distance, the flagman can effectively monitor and control the situation while minimizing the risk of injury or fatality from an approaching train. This safety protocol is vital for protecting personnel working in proximity to moving trains, as trains can approach at high speeds and may not be in time to stop if someone is too close.

Other considerations such as visibility, signal clarity, and emergency access are indeed important factors in overall operations and safety; however, the primary focus of the safety distance is to provide a buffer zone that ensures the flagman can perform their duties without being in danger from passing trains.