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SteelMaster 600WF is a one component waterborne acrylic thin film intumescent coating. It is independently approved for fire protection of structural steel exposed to cellulosic fire. This product can be used as mid coat or finish coat in atmospheric environments, and is suitable on approved primers on carbon steel substrates. The declared product is specially designed as passive fire protection for steel constructions. It is designed to protect up to 60 minutes on a wide range of I section beams and columns, and will provide 90 minutes fire duration as per BS476 part 20-21. This product is suitable for structural steel exposed to internal environments up to corrosivity category C3 (ISO 12944 -2).