How can controlled access zones be identified at an airport?

Controlled access zones at an airport are critical for ensuring the safety of both personnel and aircraft operations. Identification of these zones serves to restrict movement and access to only those who are authorized, thereby minimizing the risk of accidents and enhancing operational efficiency.

The correct identification method involves the use of a solid yellow hold line. This solid yellow line signifies a clear boundary that should not be crossed without proper authorization. It provides a visual cue to personnel, indicating where aircraft operations may be limited and where access should be controlled.

In contrast, the other methods listed do not convey the same level of restriction typically associated with controlled access. For instance, red striped lines are often used to indicate general hazardous areas but do not specifically designate controlled zones. Flashing blue lights might be utilized for different signaling purposes and may not be associated directly with access restriction. Finally, a green dashed line does not align with standard practices of zone identification and could lead to confusion regarding the nature of access control.

Thus, the use of a solid yellow hold line aligns with established aviation safety practices and effectively communicates the necessity of restricted access in controlled zones at airports.