A fire suppression system for a fire zone including a first tank containing a first liquid component of a two-part foam and a second tank containing a second liquid component of the foam. The system includes at least one liquid component release device configured to be selectively capable of releasing the first and second components from their respective containers upon receipt of a signal from a fire detector upon detection of a fire. The two-part foam components are propelled through the system by a pressurized propellant that, upon release of the release device, causes the exit of the foam components from their respective tanks, through a mixing conduit to at least one nozzle. The nozzle is configured to spray the liquid component foam mixture into the fire zone wherein the foam cures into a substantially semi-rigid, closed cell foam that is substantially impermeable and may have charring and/or intumescence properties.