FM 200 is a halocarbon agent accepted as an alternative to halon for total flooding fire suppression systems. After receiving the fire signal, FM 200 is discharged totally from the cylinders within 10 seconds to fill up the space uniformly at the design concentration to extinguish the fire. The agent is retained at its design concentration in the space for a period-called 'Hold Time'-to extinguish the fire. After Hold time, when the fire is extinguished, the agent is exhausted from the space by exhaust fans before any inspection is performed.
For the design of the system, NFPA Code 2001, "Standard on Clean Agent Fire Extinguishing Systems" is followed. The Code recommends that the system be designed by a qualified clean agent extinguishing system designer. This sometimes indirectly means the agent supplier's authorized system designer.