What is a primary type of train approach warning used on controlled track?

The primary type of train approach warning used on controlled track is referred to as a watchman. A watchman is a designated person who provides protection for roadway workers by monitoring train movements in the vicinity of the work area. They use visual and auditory signals to alert workers about the approach of trains, ensuring that everyone is aware of any imminent dangers from train traffic.

In the context of roadway worker protection, the role of the watchman is crucial because it offers a direct line of communication between the worker and the train, helping to maintain safety on controlled tracks where trains have the right of way. This method emphasizes the importance of human oversight in monitoring and managing potential hazards in an active rail environment.

Other types of warnings, such as signal announcements, light signals, and trackside warning signs, can provide useful information regarding train movements. However, they may not offer the immediacy or attentiveness that a watchman provides, making the watchman an essential component in maintaining safety for roadway workers on controlled tracks.