Can also be used to seal unlined duct work prior to component removal, preventing fiberglass and inanimate particulate from becoming airborne. Dries to form a durable, flexible, moisture-resistant protective coating with a semi-gloss finish that minimizes inanimate particulate buildup on the coating surface. The high viscosity provides maximum bridging ability on insulation materials and reduces sagging and dripping when applied to the vertical and top surfaces of unlined duct. Contains a fungistatic agent to resist mold growth on the dry coating surface. Successfully tested to ASTM standard C-411 Hot Surface Performance of a Coating on Glass Fiber Blanket Insulation. ASTM E-84 Class I fire rating. Meets requirements of NFPA 90A/90B standard. Was tested in accordance with the procedures outlined in ASTM G 21 and received a No. 0 rating (No fungal growth, 0% growth on the specimens).