Mastic No. 50-44 Intumescent Coating for Structural Steel is an asbestos free, reinforced, thermal protective coating, designed for application to interior structural steel, to increase fire endurance time to one hour.
Mastic No. 50-44, when applied at a wet film thickness of 3/16” (8.55 sq. ft./US gal) – 4.76 mm (0.21 sq. m./L), on W8 x 24 and W8 x 28 (W200 x 36 and W200 x 42) structural steel, as prescribed in ULC design number O600, has been assigned a fire resistance rating of 1 hour when fire tested in accordance with ULC-Can-S101 (similar to ASTM E-119, UL-263, NFPA-251). Refer to Underwriter’s Laboratories (ULC) can label data, and test reports.
The coating dries to a hard, flexible finish that withstands structural movement or vibration and does not dust, flake, spall or crack. Spray application yields a textured, stucco-like finish which can be lightly troweled to a relatively smooth finish. Color, off white.
Application of Mastic No. 50-44 requires a heavy duty air driven pump, and a special gun. See Flame Control product data sheet for detailed information on working with No. 50-44.