CO2 Clean Agent Fire Suppression System Although CO2 is not technically classified as a “clean agent” under NFPA 2001 (because it can be hazardous to people at design concentrations), it is widely used as a gaseous total flooding or local application suppression agent for non-occupied or limited-occupancy areas. Overview Agent: Carbon Dioxide (CO2) – naturally occurring gas, colorless, odorless Fire Extinguishing Mechanism: Oxygen Displacement – reduces oxygen below combustion threshold (usually <15%) Cooling Effect – absorbs heat as it expands Applications: Mostly in non-occupied spaces or local application systems due to life safety concerns. System Types Total Flooding CO2 System Floods the entire protected enclosure to extinguish fire. Requires room integrity and pre-discharge alarms for safety. Local Application CO2 System Discharges directly on the hazard (e.g., conveyor belts, dip tanks, printing presses). Often used for open hazards where total flooding is not feasible.