True or False: Emergency vehicles are required to be chocked when parked on the airfield.

The statement that emergency vehicles are required to be chocked when parked on the airfield is false. Generally, emergency vehicles, due to their design and necessary rapid response capabilities, are not subjected to the same chocking requirements as standard ground vehicles. This allows them to remain mobile and ready to respond quickly to emergencies without delay.

In most airfield operations, chocking is typically required for vehicles that are parked for extended periods to prevent them from rolling, particularly in areas where there is risk from changes in footing, such as near the edge of paved surfaces. Emergency vehicles, however, are often parked in a ready position to respond to calls, minimizing the need for such protocols.

The other options suggest conditions under which chocking might be required, but those scenarios do not alter the basic protocol concerning emergency vehicles. Thus, indicating that emergency vehicles do not need to be chocked while parked on the airfield aligns with standard safety measures and operational readiness.