Access Control, Intrusion Detection, and Integrated Security Systems Monitoring
Access control fundamentals
Understand the credential (card, fob, PIN, biometric), the reader, the controller, the electric lock, and the door position switch. Know access levels, time zones, anti-passback (preventing a card being used twice to pass a barrier), tailgating, door-held and forced-door alarms, and fail-safe versus fail-secure locking. Fail-safe unlocks on power loss (life safety egress); fail-secure stays locked (asset protection) and must still meet fire-egress rules.
Intrusion detection
Know the main detector types: passive infrared (PIR) (body heat and movement), dual-technology (PIR plus microwave, fewer false alarms), perimeter beams, glass-break, vibration, and door contacts. Understand zones, part-setting, and masking or tamper alarms. Environmental causes of false alarms include sunlight, draughts, insects, and animals.
Integrated monitoring
Integrated systems link access control, intrusion, fire, and CCTV on one platform. Understand event correlation (a door-forced alarm plus a camera view plus a card event tells a story), alarm prioritisation, and system health monitoring (offline devices, failed backups, expired certificates). A camera that is offline is a security gap, not a minor fault.
Traps
Questions confuse fail-safe with fail-secure, or assume an access event proves identity - a card can be borrowed or stolen. Another trap: treating an offline device as "probably fine."
Rule of thumb
A card identifies a credential, not a person. Pair access events with camera verification whenever the stakes are high, and report offline devices immediately.
Worked example
A door-held alarm sounds at a secure store, and the camera shows the door propped with a box. Correct action: treat it as a security breach, dispatch a patrol, log the event, and review who last used the door - not simply to reset the alarm remotely.