What does a Blue Signal displayed on a track or on equipment indicate?

A Blue Signal displayed on a track or on equipment is an important safety indicator within the railroad industry. It specifically signifies that there are workers either on, underneath, or in between the equipment. This signal warns train operators and other personnel that they must not move or operate the equipment in question until those workers are safely clear. The use of a Blue Signal is part of ensuring a safe working environment, protecting the lives of personnel who are performing maintenance or repairs.

This clear, visual communication is essential for preventing accidents and ensuring that everyone on and around the tracks is aware of ongoing work activities. Understanding the meaning of these signals is crucial for anyone involved in railroad operations, as it helps maintain safety protocols and operational efficiency in the presence of maintenance work.