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Construction Documents <br />20052.02 / Orange County - Justice <br />Facility <br />23 3100 - 1 HVAC DUCTS AND CASINGS <br />SECTION 23 3100 <br />HVAC DUCTS AND CASINGS <br />PART 1 GENERAL <br />1.01 SECTION INCLUDES <br />A.Metal ductwork. <br />B.Nonmetal ductwork. <br />C.Casing and plenums. <br />1.02 REFERENCE STANDARDS <br />A.ASTM A653/A653M - Standard Specification for Steel Sheet, Zinc-Coated (Galvanized) or <br />Zinc-Iron Alloy-Coated (Galvannealed) by the Hot-Dip Process; 2018. <br />B.ASTM E84 - Standard Test Method for Surface Burning Characteristics of Building Materials; <br />2018b. <br />C.NFPA 90A - Standard for the Installation of Air-Conditioning and Ventilating Systems; 2018. <br />D.SMACNA (DCS) - HVAC Duct Construction Standards Metal and Flexible; 2005 (Revised <br />2009). <br />1.03 SUBMITTALS <br />A.See Section 01 3000 - Administrative Requirements, for submittal procedures. <br />PART 2 PRODUCTS <br />2.01 DUCT ASSEMBLIES <br />A.Regulatory Requirements: Construct ductwork to comply with NFPA 90A standards. <br />B.Ducts: Galvanized steel, unless otherwise indicated. <br />C.Low Pressure Supply (Heating Systems): 1/2 inch w.g. (125 Pa) pressure class, galvanized <br />steel. <br />2.02 MATERIALS <br />A.Galvanized Steel for Ducts: Hot-dipped galvanized steel sheet, ASTM A653/A653M FS Type B, <br />with G60/Z180 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 <br />ducts. <br />2.Surface Burning Characteristics: Flame spread index of zero and smoke developed index <br />of zero, when tested in accordance with ASTM E84. <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.Increase duct sizes gradually, not exceeding 15 degrees divergence wherever possible; <br />maximum 30 degrees divergence upstream of equipment and 45 degrees convergence <br />downstream. <br />D.Fabricate continuously welded round and oval duct fittings in accordance with SMACNA (DCS). <br />2.04 MANUFACTURED DUCTWORK AND FITTINGS <br />A.Flexible Ducts: Two ply vinyl film supported by helically wound spring steel wire. <br />1.Pressure Rating: 10 inches WG (2.50 kPa) positive and 1.0 inches WG (250 Pa) negative. <br />2.Maximum Velocity: 4000 fpm (20.3 m/sec). <br />3.Temperature Range: Minus 10 degrees F to 160 degrees F (Minus 23 degrees C to 71 <br />degrees C). <br />DocuSign Envelope ID: 09980A3B-0691-41B4-854D-3865F2287392