Why is the BAK-15 considered an emergency barrier and only installed in the overrun?

The BAK-15 is classified as an emergency barrier specifically for installation in overrun areas primarily because of the lengthy reset times associated with it, in conjunction with the high costs of component replacement. When an emergency barrier is deployed, it requires a significant amount of time to reset it back to its original position after being activated, which can hinder the safety and functionality of a runway area.

Additionally, the cost implications related to component replacement add to the rationale for its placement solely in overrun zones. If maintenance and replacement of the barrier components are expensive, it becomes essential to minimize instances where the barrier needs to be reset and replaced. Thus, this type of barrier is primarily found in areas where its use can be strictly controlled and limited to emergency situations, thereby making it both a practical and financially viable option for ensuring runway safety during emergencies.