A. General provisions and other plumbing systems are specified in other Sections of Division 22.

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1 PART 1: GENERAL 1.01 DESCRIPTION: A. General provisions and other plumbing systems are specified in other Sections of Division 22. B. This Section covers the natural gas system and equipment. C. See Section , Plumbing Fixtures for fixtures and trim. D. See Section , Drainage Systems for drainage, waste, and vent systems. E. See Section , Water Systems for water systems. F. See Section , Laboratory Systems for laboratory systems. G. Commissioning is specified in Section , Commissioning. This Section includes responsibilities and obligations in support of the commissioning process specified therein QUALITY ASSURANCE: A. Natural gas system and gas-fired equipment shall conform to the following: 1. Canadian Standards Association (CSA) and the Canadian Gas Association (CGA) requirements. 2. International Fuel Gas Code NFPA Rules of the local gas company. B. Welder certification: welders shall be certified under the rules of the National Certified Pipe Welding Bureau and qualified by either the National Certified Pipe Welding Bureau or an independent testing laboratory for the procedures used on this Project. C. Welding procedures: in accordance with ASME B and ASME B for the service involved. Welds shall be full penetration type, accomplished by proper beveling and spacing of pipe ends. Where backing rings are specified herein, root pass shall penetrate into the backing ring GAS RELATED EQUIPMENT: A. Laboratory equipment using gas is specified in another Division. PART 2: PRODUCTS 1. Laboratory gas outlets, except as specified otherwise herein, shall be furnished with the equipment and turned over for installation under this Section PIPING, FITTINGS, AND JOINTS: 1. Piping and fitting sizes listed are nominal inside diameter. B. Natural gas, above grade, not in return air plenums, and connections to equipment: 1. Piping: black steel, schedule 40, ASTM A53/A53M Fittings: standard weight malleable iron, ASME B Joints: threaded. 4. Corrosion protection: painted. ETB # North Central Advanced Technology Center

2 C. Natural gas, above grade, in return air plenums, except connections to equipment: 1. Piping: black steel, schedule 40, ASTM A53/A53M Fittings: a. Forged steel socket weld, 1.5" and smaller, ASME B b. Standard weight black steel, butt weld, 2" and larger, ASME B Joints: welded. 4. Corrosion protection: painted. D. Natural gas, underground: 1. Piping: black steel, schedule 40, ASTM A53/A53M Fittings: a. Forged steel socket weld, 1.5" and smaller, ASME B b. Standard weight black steel, butt weld, 2" and larger, ASME B Joints: welded. 4. Corrosion protection: fusion-bonded epoxy coating with anode system. E. Flexible gas piping above grade, 0.5" to 2", for connections to equipment only: 1. Piping: corrugated, semi-rigid stainless steel tubing jacketed with yellow polyethylene sleeving, conforming to NFPA Fittings: brass mechanical attachment type terminating with male NPT pipe threads. 3. Joints: threaded. 4. Manufacturer: Omegaflex Tracpipe SPECIALTY PIPING JOINTS: A. Unions: 2.03 VALVES: 1. For steel piping 2" or smaller: ground joint with brass-to-iron seat. 2. For copper piping 2" or smaller: cast brass or bronze with copper soldered connections. 3. For piping larger than 2": flange and gasket type. Flanges in steel piping shall be cast iron. 1. Valves shall be of the same manufacturer, unless specified otherwise herein. B. Plug Valves: 1. Lubricated plug type, 0.5" through 3" with cast iron body, wrench handle control, 100% full flow rectangular port, threaded-ends, ASTM A (2009) Class B for 200 psig wog. a. Manufacturer: Homestead 601, Nordstrom 524, Resun D500, or Walworth ETB # North Central Advanced Technology Center

3 2. Lubricated plug type, 4" through 8" with cast iron body wrench handle control, 100% full flow rectangular port, flanged-ends, ASTM A (2009) Class B for 200 psig wog. a. Manufacturer: Homestead 602/602A, Nordstrom 115/185, Resun D126, or Walworth 1700F/1725F. C. Ball Valves - Low Pressure: 1. For building systems to 14" wg: bronze body, chromium-plated brass ball type with lever or tee handle, and threaded connections for valve sizes 0.5" to 1". Valves shall comply with ANSI Z21.15/CGA , Addendum ANSI Z21.15a-2001/CGA 9.1a-2009/ANSI Z21.15a-2009/CSA 9.1a-2009 for maximum 14" wg pressure. 2. Manufacturer: Apollo GB-10, Hammond 875, Kitz 68, or Maxitrol BV602. D. Earthquake Valves: 1. Horizontal earthquake sensitive gas shut-off valves, with swing check valve arrangement and acceleration sensitive triggering mechanism, with manual reset, 0.75" through 8", for inlet pressures to 60 psig. Valve bodies shall be constructed of die cast aluminum with an anodized powder coat finish, threaded or flanged ends, and site glass to view status of trip mechanism. Valves shall have a 30 year warranty, be UL listed, and meet the requirements of ASCE Manufacturer: Pacific Seismic Products EMERGENCY GAS SHUTOFFS: A. Emergency gas shutoffs shall consist of an electronic push switch and components, and remote gas solenoid valve. B. Electronics shall be housed in a NEMA 1 rated 16 gauge steel box with a brushed 16 gauge stainless steel door panel complying with UL Furnish the box and faceplate for recessed installation in drywall construction. C. Units shall be provided with a keyed switch to activate the system to the "on" or "off" position, a red panic push button to disengage the gas system, a keyed reactivation after the system has been disengaged, and a routed sign fastened to the wall over the unit labeled, "Emergency Gas Shutoff". Unit shall also be provided with a remote panic button assembly having keyed reset. D. Each unit shall have a 120 V solenoid valve (normally closed and energized open) of the size as indicated on the Drawings. E. Manufacturer: ISIMET LSP 4211 with keyed on/off switch in lieu of toggle switch and ISIMET IP-O-K GAS PRESSURE REGULATORS: A. Natural Gas Pressure Regulators: 2.06 ACCESSORIES: 1. Self-contained direct or lever operated service regulators with cast iron or steel valve, aluminum diaphragm housing with screened vent, balanced-diaphragm, O-ring seals, full internal pressure relief, changeable brass orifice, and adjustable color-coded spring. 2. Regulators shall have over pressure protection, and under pressure protection, each with manual reset as applicable. 3. Manufacturer: Elster American, Fisher, or Maxitrol. A. Gaskets in natural gas piping: aluminum, O-ring type. B. Bolts and nuts: ASTM A , Grade B. ETB # North Central Advanced Technology Center

4 PART 3: EXECUTION 3.01 GENERAL PIPING INSTALLATION: 1. Piping shall be cut to measurements established at the site and worked into place without springing or forcing. 2. Use concentric reducing fittings between different size piping. 3. Ream steel piping after cutting, turn on end and knock loose dirt, scale, and filings from interior of pipe. 4. Pitch natural gas piping down to the main or low point 0.5" per 10'. Take branch piping off the top of mains. Install a water leg or trap with drain valve at low points and bottoms of risers. B. Underground: 1. Install gas piping outside the building in trenches separate from water and sewers. 2. Excavation and backfill: as specified in Section , General. 3. Underground piping shall be connected to the exterior service lines, or capped or plugged if the exterior service is not in place. C. Aboveground: 1. Pipes shall be installed to permit free expansion and contraction without damage to joints, hangers, or the building. Arrange piping to minimize stresses caused by expansion and contraction. 2. Group exposed pipe together and arrange control valves at fixtures for ease of operation. 3. Install piping so as to preserve access to valves and equipment and to provide the maximum headroom possible. 4. Provide offsets to maintain ceiling height and to coordinate with other trades. 5. Dirt pockets shall be line size and 6" long minimum. Terminate with threaded cap or flange. D. Piping Joints: 1. Threaded joints: screw-thread joints shall be made with cut tapered threads. Joints shall be made tight with joint compound. Not more than 2 threads shall show after the joint is made tight. 2. Welded Joints: a. Mitering or notching pipe to form elbows and tees will not be permitted. Field and shop bevels shall be in accordance with the standards specified herein and shall be done by mechanical means or flame cutting. Where beveling is done by flame cutting, surfaces shall be cleaned of slag, scale and oxidation prior to welding. Before welding, the component parts to be welded shall be aligned so no strain is placed on the weld when finally positioned. Height shall be aligned so that no part of the pipe wall is offset by more than 20% of the wall thickness. Flanges and branches shall be set true. This alignment shall be preserved during the welding operations. Connections larger than 6" shall be made with backing rings at welds. b. Where the temperature of the component parts being welded reaches 32 F or lower, the material shall be heated to approximately 100 F for a distance of 3' on each side of the weld before welding, and the weld shall be finished before the material cools to 32 F. c. Welders shall stamp each weld with his personal symbol or code number. ETB # North Central Advanced Technology Center

5 d. Defective welds shall either be cut out and rewelded or ground down to base metal and rewelded. Reworked welds shall be tested as specified herein. e. A random sample of completed pipe welds may be chosen by the Engineer for visual and/or nondestructive testing by an independent testing agency, not to exceed 5% of the total welds on the Project. Costs for testing shall be borne by the Contractor. Acceptance criteria shall be as specified by ASME B and ASME B If any of the tested welds are unsatisfactory, additional welds may be chosen for testing at the Contractor's expense. 3. Flanged joints: flanged joints in natural gas piping shall be made with O-ring gaskets. Flanged connections to equipment shall be made with full face gaskets to match flanges on equipment. 4. Insulate joints between dissimilar metals and connections to equipment with dielectric fittings. 5. Provide flanges or unions at connections to valves and apparatus BLACK STEEL PIPE AND FITTINGS: A. Changes in direction shall be made with fittings, except where branches are two or more sizes less than the size of the main, the branch may be made using forged steel branch connections, weldolets, threadolets, latrolets, sweepolets, and elbolets FLEXIBLE PIPING: A. Install with caution and using the manufacturers' instructions SPECIALTY PIPING JOINTS: A. Unions: 3.05 VALVES: 1. Provide in each connection to each piece of equipment, except where flanges are used. A. General Requirements: 1. Provide a full size valve in the main gas line inside the building for the building shutoff. 2. Provide a full size valve to control each gas main, branch line, and supply line to gas using equipment. B. Plug Valves: 1. Provide a minimum of 1 gas valve wrenches per size of gas valve operating nuts. 2. Valves shall be lubricated before shipment. C. Earthquake Valves: 1. Install earthquake valves only in series as shipped from the factory: for horizontal valves, the horizontal position; and for vertical valves, the vertical position GAS PRESSURE REGULATORS: 1. At building startup, provide additional regulator orifices, springs, and accessories to ensure that gas regulators will function properly from 0% to 100% equipment operation. 2. Install regulators with vent openings facing down. 3. Supply pipes shall not be more than one pipe size smaller or larger than the regulator's pipe size. ETB # North Central Advanced Technology Center

6 4. Adjust the regulator springs with a minimum 5% of the system's designed flow, flowing. Select the spring with the system's operating pressure not at the spring's minimum and maximum pressure settings. 5. When the regulator serves an engine-generator set, the distance from the regulator outlet to the engine-generator set connection shall not exceed 10'. B. Regulator Vent Piping: 1. Gas pressure regulator vents: provide vent piping to a point outside the building at least 10' above finished grade, 10' from any outside air intake, and minimum 5' from any building opening. Each vent connection to a regulator shall be increased 1 pipe size, and routed independently outside. 2. Water heater and boiler gas pressure regulator vents: provide vent piping to a point outside the building at least 10' above finished grade, 10' from any outside air intake, and minimum 5' from building opening. Each vent connection to an appliance regulator, and block and vent valve, shall be increased 2 pipe sizes, and routed independently outside. 3. Vents from normally open solenoid vent valves shall be increased 2 pipe sizes, and routed independently outside. 4. Terminate vent piping with down-turned elbows, and secure insect screens to the open ends CORROSION PROTECTION: A. Corrosion Protection for Buried Ferrous Piping: 1. Buried ferrous natural gas piping shall be protected from corrosion by a factory applied exterior coating. 2. The coating shall be a factory applied coating of fusion-bonded epoxy (FBE). The coating shall be applied to cleaned pipe, to a minimum dry film thickness of 18 mil. Pinholes or minor abrasions shall be repaired using a patch compound provided by the coating manufacturer. 3. Fittings, valves, and bare piping ends either side of joints shall be cleaned, and coated with a field coat of liquid epoxy coating (LEC), as provided by the pipe coating manufacturer, to a dry film thickness of 40 mil. 4. Installation: a. Install piping with FBE coating, coating patch, and LEC per manufacturer's instructions and safety precautions. b. Ensure that any patch compound and LEC are completely dry before covering with backfill. B. Above grade ferrous piping, fittings, and valves, exposed where moisture can produce rust shall be cleaned, primed, and painted with 2 coats of exterior grade silver paint ROOF PENETRATIONS: A. Flash and counter-flash pipes passing through the roof with 4 psf sheet lead, not less than 18" square GAS RELATED EQUIPMENT: 1. After gas related equipment has been installed, provide piping, isolation valves, and accessories as specified herein, and make final connections. 2. The location and number of connections shown on the Drawings is approximate. Determine the exact number, location, and rough-in requirements from the equipment drawings and specifications. ETB # North Central Advanced Technology Center

7 B. Equipment: 1. For gas piping, rough-in each at 6" from wall or 6" above floor, unless otherwise indicated on the Drawings, with a valve and cap PIPING AND JOINT TESTS: A. Test natural gas system piping by capping openings and applying an air pressure of 100 psig for 2 hours without any leaks. Disconnect the air source prior to and during testing. Where the system is tested in sections, each section shall be subjected to the same test. B. Piping General: 1. Test piping under floor slabs before slabs are poured. 2. Tests shall be made while piping and joints are exposed to view. 3. Submit a statement certifying that piping and joints are tight and have passed the specified test. C. Piping Test General: 1. Screwed and flanged joints that leak shall be taken apart and reassembled. 2. Brazed joints that leak shall be taken down and replaced. END OF SECTION ETB # North Central Advanced Technology Center