Control #4
The "Exit" has demonstrated various types of control to secure the physical perimeter while enable a "kill switch" to emergency situation.
The door lock acts as preventive control in normal circumstance. Inbound entry to the hall is prohibited by civilians (not stopping armed force). The lock bar can be pushed out to evacuate people in case emergency inside. It must be easily activated. To guard against abuse by malicious actor, CCTV camera is monitoring the scene.
However, detective control must be supported by administrative control or else it won't be enforceable. Let's say, putting another notice there to indicate improper use will be subject to fine or imprisonment per bylaw clause so and so.
Furthermore, security system is the first target to attack for disabling its surveillance function such that "improper" activities can be conducted without being caught.
Altogether, this are the typical people, process, technologies, policies aspects that should be considered in formulating the use case, security and safety.
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