What must AVOP holders do before entering an active runway?

AVOP holders must obtain clearance from Air Traffic Control (ATC) before entering an active runway to ensure safety and coordination with ongoing aircraft operations. This requirement is critical because active runways are locations where aircraft are taking off and landing, making it essential for ground vehicles to have explicit permission to enter these areas. By securing clearance, vehicle operators help prevent potential accidents and ensure that both aircraft and vehicular traffic can operate safely and efficiently on the airfield.

The other options involve important practices for overall safe operations but are not specific to the protocol of entering an active runway. For example, while performing a vehicle inspection is essential for ensuring the vehicle is safe to operate, it does not address the critical need for communication with ATC. Similarly, signaling to nearby aircraft could be part of safe practices but does not replace the need for formal clearance from ATC. Checking weather conditions is relevant to overall situational awareness but does not pertain directly to the procedural requirement for entering an active runway.