What must be done if a vehicle operator encounters an emergency while driving airside?

When a vehicle operator encounters an emergency while driving airside, the priority is to ensure safety and proper communication. Alerting the nearest supervisor immediately is crucial because they can assess the situation, coordinate a response, and notify necessary personnel or emergency services. This communication helps manage the emergency effectively, ensuring that the appropriate actions are taken and resources are deployed as needed.

This action also aligns with safety protocols designed to protect not only the vehicle operator but also other personnel and aircraft in the vicinity. Immediate notification allows for a quicker and more organized response to the emergency, reducing potential risks and hazards. The other choices do not provide the same level of safety or responsiveness, as they lack the required communication and oversight needed in such situations.