Security Technology and Physical Security Systems
Systems
CCTV, access-control panels, intrusion alarms, fire detection, intercoms, and radios are tools that support people, not replacements. Know the coverage gaps and the recording retention period. Preserve footage after an incident and log who accessed it; chain of custody matters. Access-control data such as card swipes can prove who entered and when.
Physical security
Locks, bollards, lighting, fencing, turnstiles, and safe rooms buy time. Crime Prevention Through Environmental Design (CPTED) uses natural surveillance, access control, and maintenance. Test alarms and report faults; a silent alarm is not a response.
Worked example
At 23:40 an intrusion alarm activates at a rear door. The guard views the camera, sees no one, and dispatches a patrol to physically check the door. He does not reset the alarm from the panel without verification. He finds the door unlocked, secures it, and writes a report with the alarm time, camera check, and physical check.
Traps
Assuming cameras prevent crime; deleting footage; sharing passwords; resetting alarms without checking; ignoring nuisance alarms until a real one is missed.