Clean agents work to cause extinguishment through three main mechanisms
Absorption of Energy from the Fire: Clean agents, with their high heat capacities, increase the energy losses from the fire. Some of the available agents undergo endothermic decomposition reactions in the presence of a fire further increasing the energy loss from the fire. Displacement of Oxygen: Clean agents, by their presence in the enclosure, reduce the concentration of oxygen in the enclosure. This reduces the amount of oxygen available to support combustion and reduces the amount of energy produced by the fire. Interference in the Combustion Reaction: Some clean agents, after undergoing decomposition reactions in the presence of the fire, produces free radicals which interfere with the combustion reaction

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