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DocuSign Envelope ID: B94F2D40-3B3C-47A7-86C2-6F1 B4F92C62C <br /> Orange County Emergency Services Building Construction Documents <br /> 2.02 MATERIALS <br /> A. Galvanized Steel for Ducts: Hot-dipped galvanized steel sheet, ASTM A653/A653M FS Type B, <br /> with G90/Z275 coating. <br /> B. Joint Sealers and Sealants: Non-hardening, water resistant, mildew and mold resistant. <br /> 1. Type: Heavy mastic or liquid used alone or with tape, suitable for joint configuration and <br /> compatible with substrates, and recommended by manufacturer for pressure class of ducts. <br /> 2. VOC Content: Not more than 250 g/L, excluding water. <br /> 3. Surface Burning Characteristics: Flame spread index of zero and smoke developed index of <br /> zero, when tested in accordance with ASTM E84. <br /> 4. For Use With Flexible Ducts: UL labeled. <br /> C. Hanger Rod: ASTM A36/A36M; steel, galvanized; threaded both ends, threaded one end, or <br /> continuously threaded. <br /> D. Hanger Fasteners: Attach hangers to structure using appropriate fasteners, as follows: <br /> 1. Concrete Wedge Expansion Anchors: Complying with ICC-ES AC193. <br /> 2. Masonry Wedge Expansion Anchors: Complying with ICC-ES AC01. <br /> 3. Concrete Screw Type Anchors: Complying with ICC-ES AC193. <br /> 4. Masonry Screw Type Anchors: Complying with ICC-ES AC106. <br /> 5. Concrete Adhesive Type Anchors: Complying with ICC-ES AC308. <br /> 2.03 DUCTWORK FABRICATION <br /> A. Fabricate and support in accordance with SMACNA (DCS)and as indicated. <br /> B. Provide duct material, gages, reinforcing, and sealing for operating pressures indicated. <br /> C. Construct T's, bends, and elbows with radius of not less than 1-1/2 times width of duct on <br /> centerline. Where not possible and where rectangular elbows must be used, provide air foil turning <br /> vanes of perforated metal with glass fiber insulation. <br /> D. Increase duct sizes gradually, not exceeding 15 degrees divergence wherever possible; maximum <br /> 30 degrees divergence upstream of equipment and 45 degrees convergence downstream. <br /> E. Fabricate continuously welded round and oval duct fittings in accordance with SMACNA(DCS). <br /> F. Where ducts are connected to exterior wall louvers and duct outlet is smaller than louver frame, <br /> provide blank-out panels sealing louver area around duct. Use same material as duct, painted <br /> black on exterior side; seal to louver frame and duct. <br /> 2.04 MANUFACTURED DUCTWORK AND FITTINGS <br /> A. Flexible Ducts: UL 181, Class 0, interlocking spiral of aluminum foil. <br /> 1. Insulation: Fiberglass insulation with aluminized vapor barrier film. <br /> 2. Pressure Rating: 8 inches WG positive or negative. <br /> 3. Maximum Velocity: 5000 fpm. <br /> 4. Temperature Range: Minus 20 degrees F to 250 degrees F. <br /> 5. Insulation: R6.0 <br /> 6. Manufacturers: <br /> a. Lindab <br /> b. Flexmaster <br /> c. Clevaflex <br /> PART 3 EXECUTION <br /> 3.01 INSTALLATION <br /> A. Install, support, and seal ducts in accordance with SMACNA(DCS). <br /> B. During construction provide temporary closures of metal or taped polyethylene on open ductwork to <br /> prevent construction dust from entering ductwork system. <br /> C. Flexible Ducts: Connect to metal ducts with adhesive plus sheet metal screws. <br /> D. Duct sizes indicated are inside clear dimensions. For lined ducts, maintain sizes inside lining. <br /> E. Provide openings in ductwork where required to accommodate thermometers and controllers. <br /> Provide pilot tube openings where required for testing of systems, complete with metal can with <br /> PDC Project 18102 HVAC DUCTS AND CASINGS 2331 00-2 <br /> 12/17/2018 <br />