What is a highly important practice before entering the airside area with a vehicle?

Checking the vehicle for functioning lights and brakes is a highly important practice before entering the airside area with a vehicle because ensuring that the vehicle is in good working condition is critical for safety. Lights and brakes are essential components that contribute to the safe operation of a vehicle, especially in a bustling and potentially hazardous environment like the airside of an airport. Properly functioning lights help ensure visibility and communication with other vehicles and personnel, while effective brakes are crucial for stopping safely when required. These measures help prevent accidents and maintain the safety of passengers, airport workers, and aircraft.

Adjusting the radio for entertainment, reviewing flight schedules, and informing passengers about safety protocols, while they can be relevant to various aspects of airport operations, do not directly address the immediate safety concerns associated with driving a vehicle airside.