What is the maximum height allowed for a vehicle to operate without a special permit?

The maximum height allowed for a vehicle to operate without a special permit is 13 feet 6 inches. This regulation is designed to ensure safe travel on public roads, preventing vehicles from colliding with overhead structures like bridges and overpasses that may not accommodate taller vehicles. When a vehicle exceeds this height, it poses a risk not only to the driver but also to other road users and infrastructure.

Therefore, the correct answer reflects the federal and state guidelines that dictate the height restrictions for commercial vehicles, ensuring compliance with safety standards. Understanding this regulation is crucial for drivers who may operate vehicles used for commercial purposes, as it helps avoid penalties and maintain safety on the roads.