What is the minimum requirement for road clearance for the fuel system in a CNG delivery truck?

The minimum requirement for road clearance for the fuel system in a CNG delivery truck is that clearance should be practical, ensuring that components do not touch the road when the truck is loaded to its gross weight. This requirement is important to account for the weight of the cargo and the vehicle's suspension characteristics.

Maintaining adequate clearance helps prevent damage to the fuel system components during operation, particularly when navigating uneven surfaces or encountering bumps. Additionally, it helps ensure safe operation by reducing the risk of the components scraping the ground, which could lead to leaks, safety hazards, or equipment failure.

Considering the other options, measuring clearance to the highest component does not take into account the load variability and potential for components to sag or flex under weight. Allowing components to touch the road in case of a flat tire would not be safe or practical, as it could further compromise the safety and functionality of the fuel system. Lastly, stating that no clearance restrictions are needed overlooks critical safety considerations essential for safe operation on public roads.