AbstractWater‐based foams that are commonly used to extinguish pool and tank fires of flammable liquids can also be used to suppress the vaporization of flammable liquids pools prior to ignition. To suppress vaporization from pools of water‐soluble or water‐reactive chemicals, specialized foams or dry chemical agents may be more effective than typical low expansion, water‐based foams. Water‐based high expansion foams can be used to mitigate hazardous vapor clouds created by vaporization from pools of some liquefied gases. This paper discusses the advantages and limitations of these vapor suppression t