Audio
Balanced capacitance
Buried sensors
Dual technology detectors
Electromagnetic, field disturbance
Electrostatic, field disturbance
Fibre optic continuity circuits
Infrared beams, active
Infrared illuminators
Infrared, passive (PIR)
Loop detectors
Motion detectors
Photoelectric beam
Portable intrusion detection
Pressure sensors, buried
Proximity sensors
Seismic sensors, buried
Shock detectors
Taut wire systems
Underwater fibre-optic continuity grid
Vehicle sensors, buried
Vehicle sensors, drive through
Vehicle sensors, magnetic
Vibration sensors
Volumetric sensors
