Specifications include, but are not limited to: A. System components and connections shall have pressure rating equal to or greater than system operating pressure. B. Welding applications shall be in compliance with American Welding Society Standards. C. Structural Steel for Supports: ASTM A36. 1. Fan plenums or areas of high humidity or condensation, tunnels and outside: galvanized members. 2. Furnish other members with shop coat of primer. 3. All fasteners shall be stainless steel. D. Pipe, Tube and Fittings 1. Refer to individual piping Sections for pipe, tube, and fitting materials and joining methods. 2. Pipe Threads: ASME B1.20.1 for factory-threaded pipe and pipe fittings. 3. Dielectric Fittings a. Description: Combination fitting of copper alloy and ferrous materials with threaded, solder-joint, plain, or weld-neck end connections that match piping system materials. b. Insulating Material: Suitable for system fluid, pressure, and temperature. c. Dielectric Unions: Factory-fabricated, union assembly, for 150-psig minimum working pressure at 180 deg F (82 deg C). d. Dielectric Flanges: Factory-fabricated, companion-flange assembly, for 150-psig minimum working pressure as required to suit system pressures. e. Dielectric Couplings: Galvanized-steel coupling with inert and noncorrosive, thermoplastic lining; threaded ends; and 150-psig minimum working pressure at 225 deg F (107 deg C). f. Dielectric Nipples: Electroplated steel nipple with inert and noncorrosive, thermoplastic lining; plain, threaded, or grooved ends; and 150-psig minimum working pressure at 225 deg F (107 deg C). E. Joining Materials – where not otherwise specified: 1. Plastic, Pipe-Flange Gasket, Bolts, and Nuts: Type and material recommended by piping system manufacturer, unless otherwise indicated. 2. Solder Filler Metals: ASTM B 32, lead-free alloys. Water-flushable flux according to ASTM B 813. 3. Brazing Filler Metals: AWS A5.8, BCuP Series or BAg1, unless otherwise indicated. 4. Welding Filler Metals: Comply with AWS D10.12. 5. Solvent Cements for Joining Plastic Piping: a. ABS Piping: ASTM D 2235. b. PVC Piping: ASTM D 2564. Include primer according to ASTM F 656. c. PVC to ABS Piping Transition: ASTM D 3138...