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SteelMaster 600WF is a one component waterborne acrylic thin film intumescent coating. Independently approved for fire protection of structural steel exposed to cellulosic fire. Can be used as mid coat or finish coat in atmospheric environments. Suitable on approved primers on carbon steel substrates. Typical use SteelMaster 600WF is specially designed as a reactive fire protection system for steel constructions. Designed to protect up to 90 minutes on a wide range of I section beams and columns. Fire tested and approved to BS 476 part 20/21. Suitable for structural steel exposed to internal environments.