Barrier systems are considered __________ if they require action by personnel or equipment to allow entry.

• A. Passive
• B. Active
• C. Automatic
• D. Manual

Answer: (B)

Barriers are classified by whether they sit idle and block by default or require some action to permit entry. A passive barrier blocks entry without any action and stays inert until change. If entry can occur only after someone acts or an automated system performs a function to open the barrier, that barrier is active. This covers controls operated by a person (like a guard or a manual switch) and those driven by equipment (like an access-control signal or actuator). So when entry requires action by personnel or by equipment to allow access, the barrier is active. (Manual barriers are a form of active barriers since they require human action, while automatic ones still fit the active category because they rely on a preceding trigger to open.)