What is a mandatory feature on the outer banks of elevated haulage roads?

Berms or guards are a mandatory feature on the outer banks of elevated haulage roads because they serve a crucial safety function. Their primary purpose is to prevent vehicles from slipping off the edge of the roadway, particularly in hazardous conditions or during maneuvers. These structures help to contain any potential over-excursions, thereby reducing the risk of accidents and enhancing overall site safety.

In elevated settings, where the terrain can be steep or the consequences of a fall can be severe, having an effective barrier like a berm or guard is essential. It provides a physical safeguard for equipment and operators, which is particularly important in environments where heavy machinery operates.

While other options like railings, road markers, and warning signs contribute to safety and navigation, they do not necessarily fulfill the same structural role as berms or guards. Railings might not be implemented in some contexts due to space limitations or specific site design. Road markers and warning signs, although important for guidance and awareness, do not prevent vehicles from leaving the designated roadway. Thus, the presence of berms or guards is a fundamental requirement in maintaining safety on elevated haulage roads.