The multi-sensor combines heat (H), carbon monoxide (CO), optical forward scatter (OFS) and optical backward scatter (OBS) The patented dual angle optical scatter technology allows identification of the particle source filtering potential false alarms due to steam and dust The gas sensing element (CO) within the chamber monitors the concentration of carbon monoxide, a product of incomplete combustion in some fire types, and potentially life threatening. The CO sensor allows rapid fire detection, with smouldering fires, in areas where smoke detectors could register false alarms Combined CO gas sensing with dual angle optical and heat allows a higher level of false alarm immunity whilst still improving the detection speed of certain types of fire Each sensor element has sensitivity settings which can be adjusted to suit the environment / application and can be programmed for different time periods during the day or night Repeat fire LED output as standard (if monitored input not used) Operational LED blink ‘On/Off’ option Monitored Input - which can be Fire, Fault or Supervisory