Texas Compressed Natural Gas (CNG) Delivery Truck Driver Practice Exam

The horizontal guard railing should be secured to vertical supports. This design is crucial because vertical supports provide the necessary stability and strength to the railing system. By anchoring the horizontal elements to vertical supports, it creates a robust framework that can withstand the forces applied to it, such as weight from leaning or accidental bumps. Furthermore, vertical supports are typically anchored securely to a firm base, ensuring that the entire guard railing system remains steady and effective in providing safety. While other materials such as concrete foundations and wooden posts can be part of the overall construction, the primary role of vertical supports is to directly bear the load of the horizontal guard railing, making this the optimal choice.