Foster® Safetee™ Duct Sealant 32-17

• Foster® Safetee™ Duct Sealant 32-17 is a fire-resistive, fibrated, water-based, indoor/outdoor vapor barrier sealant for low, medium and high velocity heating and air conditioning ducts.
• It performs as a tough and flexible adhesive and sealant, forming a durable seal against air leakage when used with or without reinforcing tape or membrane.
• Mechanical fasteners of the type and number normally used for duct assemblies are required to provide rigidity to the duct system.
• Foster® Safetee™ Duct Sealant 32-17 has excellent weather resistance, low water vapor permeance and good water resistance, allowing it to be used outdoors and in high humidity environments.
• It is U.V. resistant. When dry, it may be painted with good quality, water-based paint.
• Foster® Safetee™ Duct Sealant 32-17 may be pressure tested within 16 hours dry time above 70ºF (21ºC) and below 60% RH.
• It quickly forms a strong bond to galvanized, aluminum or mild steel metal ducts. It has a mild odor when wet.

Material preparation

• Do not thin.
• Apply only to clean, dry, oil-free surfaces.
• Keep container closed when not in use.

Application 

• UL 181B MASTIC CLOSURE OF UL 181 FLEXIBLE AIR DUCTS:
• Apply to clean, dry, oil-free surfaces by brush, trowel or power extrusion.
• Uniformly brush out a 2” wide coat over the joint, at the nominal rate of 2 gal./100 sq. ft. (0.8 l/m2 ).
• Total coverage rate to be 45 – 55 sq. ft./gal. (1.1 – 1.4 m2 /l).
• Allow the completed joint to dry at least 24 hours above 70ºF (21ºC) before pressure testing. High humidities (over 70%) and/or cooler temperatures may retard drying.
• Total wet film thickness to be 32 mils +/- 3 mils.
• Other sealing applications – NOT UL 181:
• Apply a continuous film of Foster® Safetee™ Duct Sealant 32-17 over all areas of the indoor or outdoor duct system where air leakage may occur.
• A brush may be used to work the sealant into joints and remove excess.
• On spiral ducts, apply a coat to the male end of the coupling prior to fitting the straight run of spiral duct over it.
• Brush excess Foster® Safetee™ Duct Sealant 32-17 over the joint to complete the seal.
• Screw holes and flanges should also be sealed with a coat of Foster® Safetee™ Duct Sealant 32-17.
• It may be applied to the inside or the outside of the duct.
• Power extrusion:
• Foster® Safetee™ Duct Sealant 32-17 may be applied using a wide variety of power (pressure) extrusion equipment suitable for use with water-based sealants.
• It is a soft buttery gel with a typical viscosity range of 130,000 – 160,000 cps.
• Corrosion resistant pumps and fittings are suggested.
• Top coating
• After it is completely dry, Foster® Safetee™ Duct Sealant 32-17 may be top coated with good quality water-based paint.

Clean up 

• Use fresh water to clean brushes and equipment before product dries.
• Dry product may be removed with hot soapy water or strong solvent such as chlorinated solvent (non-flammable) or xylol (flammable).

• Always test plastic materials for compatibility when using a solvent-based product.
• Systems may be pressure-tested 36 hours after application, above 60°F (16°C).
• Make certain this product is completely dry and the area free from solvent odor if food is involved.

• Store and apply between 40°F (4°C) and 100°F (38°C).

¹ - Tested as applied in two 2” wide strips spaced 8 in. on center at a coverage of 26.7 sq. ft./gal. Applied to 1/4 inch (6.4 mm) inorganic reinforced cement board. The flame spread may vary at different product thicknesses and/or when applied over other surfaces.