Barrier systems are classified as __________ if they require personnel or equipment action to permit entry.

Barrier systems classified as active are those that necessitate an action by personnel or equipment to allow entry. This means that these systems are not simply physical obstructions; they require a proactive measure to be taken, such as pressing a button, entering a code, or a guard manually allowing access. Active systems often incorporate technology or mechanisms like electronic gates, turnstiles, or security personnel who control access. This approach provides a higher level of control and security because it requires a specific action to grant access, which can also be adjusted or monitored in real-time.

In contrast, passive barrier systems do not require any action once they are in place; they provide security through their mere presence, such as walls or fences that deter entry without any interactive component. Static barriers, while they may refer to structures that remain fixed in one position, do not necessarily imply action is required for entry. Dynamic, meanwhile, relates more to systems that might change or adapt but does not specify the requirement for personnel or equipment action specifically.

Thus, active barrier systems stand out due to their interactive nature that enhances security through controlled access.