ARDMS Lite is a highly sensitive, fixed radiation-detection system built around a CsI(Tl) scintillator and high-speed processing. It self-calibrates to local background and triggers visual/audible alarms on deviations, detecting small amounts of artificial gamma radiation even with fluctuating background. Set up near doorways, luggage/parcel feeds, car-park entrances or conveyors; people/vehicles don’t need to stop to be screened. Configuration is via embedded Linux/serial link (with password protection), and status/alarms display locally on strobes/buzzer and the built-in/connected display. Options include UPS/battery backup, a neutron probe (thermal/fast), and an alarm-triggered video recorder for time-stamped identification.