The Advanced Multi-Criteria Fire/CO Detector (AMCF/CO) combines fire and CO protection using four wires and one footprint. For fire, the detector combines four separate sensing elements in one unit (smoke, CO, light/flame, and heat) to sense multiple components of a fire. This approach enables enhanced sensitivity to real fire with heightened immunity to nuisance particulate. For CO, the detector’s electrochemical sensing cell creates a separate signal for life safety CO detection. The detector’s CO sensor can be field tested using RealTest, a CO test fully compliant with NFPA 720: 2009. The AMCF/CO works with the B200S intelligent sounder base to provide both Temp 3 and Temp 4 signals for fire and CO. The B200S can be synchronized with the manufacturer’s AV devices and used as part of the evacuation signal.