What does an Absolute Block Signal allow a train to do?

An Absolute Block Signal is critical for maintaining safe train operations by ensuring that only one train can occupy that section of track at any given time. When a train encounters an Absolute Block Signal showing a clear aspect, it is permitted to proceed at a slow speed, specifically within the interlocking limits defined for that area. This allows the train to move safely onto track where it can be assured there are no other trains currently occupying that block.

The context of interlocking limits is crucial here because they denote a controlled area where the signal system ensures the safe passage of trains. By allowing a train to proceed at slow speed, the Absolute Block Signal provides an essential safety measure, allowing for the possibility of quick stops and safe navigation through potentially complex rail environments, particularly in urban or high-traffic areas.

Understanding that an Absolute Block Signal is designed with safety in mind helps clarify why proceeding at maximum speed, stop mandates, or high-speed transit through the signal are not appropriate actions related to this type of signal.