N.Y.C. Admin. Code § FGC 404: Section FGC 404: Piping System Installation

404.1 Installation of materials.

Materials used shall be installed in strict accordance with the standards under which the materials are accepted and approved. In the absence of such installation procedures, the manufacturer's instructions shall be followed. Where the requirements of referenced standards or manufacturer's instructions do not conform to minimum provisions of this code, the provisions of this code shall apply.

404.2 Pipe movement.

Flammable or combustible gas piping systems shall be designed to account for pipe movement resulting from thermal changes or seismic forces.

404.2.1 Seismic requirements.

Gas piping shall be designed and installed to withstand seismic forces in accordance with Section 1613 of the New York City Building Code.

404.2.1.1 Stainless steel flexible multiple leg hose assemblies.

Stainless steel flexible multiple leg hose assemblies may be installed where pipe movement resulting from seismic forces may occur. Such assemblies shall be listed and labeled in accordance with UL 536 and shall be installed in accordance with the manufacturer's instructions.

404.2.1.2 Inspection.

The installation of stainless steel flexible multiple leg hose assemblies shall be subject to special inspections in accordance with Chapter 17 of the New York City Building Code.

404.3 Prohibited locations.

Piping shall not be installed in or through a ducted supply, return or exhaust duct, or a trash or clothes chute, chimney or gas vent, ventilating duct, dumbwaiter or elevator shaft. Piping installed downstream of the point of delivery shall not extend through any townhouse unit other than the unit served by such piping. Piping, fixtures, or equipment shall be located so as not to interfere with the normal operation of windows or doors and other exit openings. The following installation limitations shall apply:

1.

Stair enclosures. Gas piping shall not be installed within a stair enclosure or required exit or exit way.

2.

Fire standpipe riser. Gas piping shall not be installed in any shaft containing standpipe risers.

3.

Fire pump and fire pump rooms. Gas piping, gas consumption devices, appliances or any other gas equipment shall not be installed within any space housing a fire pump. Access to gas meter rooms shall not be permitted through rooms housing a fire pump.

4.

Fire-rated construction. Gas piping shall not be installed within a wall or assembly required to have a fire-resistance rating. Through penetrations of fire-resistance-rated assemblies shall be in accordance with Chapter 7 of the New York City Building Code.

5.

Public corridor. Gas piping shall not be installed in public corridors and exit enclosures.

Exceptions:

1. Gas piping may be installed in public corridors or exit enclosures where separated by a fire-resistance-rated assembly meeting the hour rating and, if applicable, the impact-resistance rating required for the corridor or exit enclosure. Such assembly shall be rated for exposure to fire from both sides.

2. In residential buildings that do not have floors below grade, or in multi-use buildings that have a residential occupancy, gas piping may be installed in public corridors in accordance with the following:

2.1. Gas piping shall be permitted to be installed within a public corridor at the lowest level of the building or the lowest residential level of the building.

2.2. All gas valves located within the public corridor shall be accessible for maintenance and inspection.

2.3. Gas pressure within the public corridor piping shall not exceed 1/2 psi (14 inch w.c.).

2.4. The public corridor shall be ventilated in accordance with the New York City Mechanical Code. The pipe shall not be installed in a return air plenum.

2.5. Pipes must be welded.

404.4 Piping in solid partitions and walls.

Concealed piping shall not be located in solid partitions and solid walls, unless installed in a ventilated chase or casing.

404.5 Fittings in concealed locations.

Fittings installed in concealed locations shall be limited to the following types:

1. Threaded elbows, tees and couplings.

2. Welded fittings.

404.6 Piping through foundation wall.

Underground piping, where installed below grade through the outer foundation or basement wall of a building, shall be encased in a protective pipe sleeve. Such sleeve shall extend a minimum of 1 inch (25.4 mm) beyond the inside of the foundation wall and a minimum of 4 inches (101.6 mm) beyond the outside of the foundation wall, or as otherwise required by the gas provider. The annular space between the gas piping and the sleeve shall be waterproofed and sealed.

404.7 Branch take-off.

Branches shall be taken off the riser with not less than a two-elbow swing.

404.8 Piping in solid floors.

Piping in solid floors shall be laid in channels in the floor and covered in a manner that will allow access to the piping with a minimum amount of damage to the building. Where such piping is subject to exposure to excessive moisture or corrosive substances, the piping shall be protected in an approved manner. As an alternative to installation in channels, the piping shall be installed in a conduit of Schedule 40 steel or wrought iron pipe installed in accordance with Section 404.8.1 or 404.8.2.

404.8.1 Conduit with one end terminating outdoors.

The conduit shall extend into an occupiable portion of the building and, at the point where the conduit terminates in the building, the space between the conduit and the gas piping shall be sealed to prevent the possible entrance of any gas leakage. The conduit shall extend not less than 2 inches (50.8 mm) beyond the point where the pipe emerges from the floor. If the end sealing is capable of withstanding the full pressure of the gas pipe, the conduit shall be designed for the same pressure as the pipe. Such conduit shall extend not less than 4 inches (101.6 mm) outside the building, shall be vented above grade to the outdoors and shall be installed so as to prevent the entrance of water and insects.

404.8.2 Conduit with both ends terminating indoors.

Where the conduit originates and terminates within the same building, the conduit shall originate and terminate in an accessible portion of the building and shall not be sealed. The conduit shall extend not less than 2 inches (50.8 mm) beyond the point where the pipe emerges from the floor.

404.9 Above-ground outdoor piping.

Piping installed outdoors shall be elevated not less than 3 1/2 inches (88.9 mm) above ground and where installed across roof surfaces, shall be elevated not less than 3 1/2 inches (88.9 mm) above the roof surface, identified in accordance with Section 401.5, and shall not be concealed. Piping installed above ground, outdoors, and installed across the surface of roofs shall be securely supported to the structure and located where it will be protected from physical damage. Where passing through an outside wall, the piping shall be protected against corrosion in accordance with Section 404.11. Where piping is encased in a protective pipe sleeve, the annular space between the piping and the sleeve shall be sealed. At least one end shall have a vented outlet piped to a safe location outdoors. The vent terminal shall be outdoors, minimum 18 inches (457.2 mm) above grade, not under an opening to building or overhang, and shall be installed so as to prevent the entrance of water and insects.

404.10 Reserved.

404.11 Protection against corrosion.

Metallic pipe, fittings, and joints susceptible to corrosive action, such as soil condition or moisture, shall be protected in an approved manner as set forth in Sections 404.11.1 through 404.11.6.

404.11.1 Prohibited use.

Threaded or uncoated welded joints shall not be used in piping in contact with soil. Uncoated piping, fittings, and joints shall be prohibited where internal or external corrosion is known to occur.

404.11.2 Protection of exposed pipe.

Ferrous metal exposed in exterior locations shall be protected from corrosion by one of the following methods:

1. Zinc coatings (galvanizing).

2. Bonded coatings in accordance with Section 404.11.4.

3. Protective coatings in accordance with Section 404.11.5.

4. Protective wrappings in accordance with Section 404.11.6.

404.11.3 Protection of buried pipe.

Ferrous metal installed in buried locations shall be protected from corrosion by one of the following methods:

1. Bonded coatings in accordance with Section 404.11.4.

2. Protective wrappings in accordance with Section 404.11.6.

Where dissimilar metals are joined underground, an insulating coupling or fitting shall be used. Piping shall not be laid in contact with cinders.

404.11.4 Protective bonded coatings.

Pipe protective bonded coatings shall be approved for the application and shall be factory applied.

Exception: Where installed in accordance with the manufacturer's instructions, field application of bonded coatings shall be permitted for pipe, fittings and locations where the factory coating or wrapping has been damaged or necessarily removed at joints.

404.11.5 Protective coatings.

Pipe protective coatings shall be approved for the application and shall be factory applied or field applied in accordance with the manufacturer's instructions.

Exception: Where installed in accordance with the manufacturer's instructions, field application of coatings shall be permitted for pipe, fittings and locations where the factory coating has been damaged or necessarily removed at joints.

404.11.6 Protective wrappings.

Pipe protective wrappings shall be approved for the application and shall be field applied in accordance with the manufacturer's instructions.

404.12 Minimum burial depth.

Underground piping systems shall be installed a minimum depth of 24 inches (609.6 mm) below grade, measured to the top of the pipe.

Exception: Burial depth less than 24 inches (609.6 mm) is permissible when the underground piping system is protected by steel protective plates not less than 1/4-inch thick (6.36 mm) and with joints tack welded and overlapped a minimum of 3 inches (76.2 mm). The pipe shall be not less than 4 inches (101.6 mm) below the protective steel plate.

404.13 Trenches.

The trench shall be graded so that the pipe has a firm, substantially continuous bearing on the bottom of the trench.

404.13.1 Backfilling.

Material used under and beside pipes shall be clean backfill, free of discarded construction material and debris. Loose earth free from rocks, broken concrete and frozen chunks shall be placed in the trench in 6-inch (152.4 mm) layers and tamped in place until the crown of the pipe is covered by 12 inches (304.8 mm) of tamped earth. The backfill under and beside the pipe shall be compacted for pipe support. Backfill shall be brought up evenly on both sides of the pipe so that the pipe remains aligned. In instances where the manufacturer's installation instructions for materials are more restrictive than those prescribed by the code, the material shall be installed in accordance with the more restrictive requirement. Backfilling is subject to progress inspection in accordance with Section 108.

404.14 Piping underground beneath buildings.

Piping installed underground beneath buildings is prohibited except where the piping is encased in a conduit of wrought iron or steel pipe designed to withstand the superimposed loads. The conduit shall be protected from corrosion in accordance with Section 404.11 and shall be installed in accordance with Section 404.14.1, 404.14.2 or 404.14.3.

404.14.1 Conduit with one end terminating outdoors.

The conduit shall extend into an occupiable portion of the building and, at the point where the conduit terminates in the building, the space between the conduit and the gas piping shall be permanently sealed to prevent the possible entrance of any gas leakage. The conduit shall extend not less than 2 inches (51 mm) beyond the point where the pipe emerges from the floor. The end sealing shall be capable of withstanding the full pressure of the gas pipe, and the conduit shall be designed for the same pressure as the pipe. Such conduit shall extend not less than 4 inches (101.6 mm) outside of the building, shall be vented above grade to the outdoors and shall be installed so as to prevent the entrance of water and insects.

404.14.2 Conduit with both ends terminating indoors.

Where the conduit originates and terminates within the same building, the conduit shall originate and terminate in an accessible portion of the building and shall not be sealed. The conduit shall extend not less than 2 inches (50.8 mm) beyond the point where the pipe emerges from the floor.

404.14.3 Conduit with both ends terminating indoors within different buildings.

Where the conduit originates indoors in a building and terminates indoors within a different building, the conduit shall comply with Section 404.14.2.

404.15 Outlet closures.

Gas outlets shall be permitted only under the following conditions:

1. Valved and capped gas tight outlets for appliance outlets listed on approved applications.

2. Valved and capped outlets on each floor in non-production laboratory buildings for future laboratories.

3. Listed and labeled flush-mounted-type quick disconnect devices and listed and labeled gas convenience outlets installed in accordance with the manufacturer's instructions.

Exceptions:

1. Test ports for gas riser valves installed downstream of a riser control valve.

2. Outlets for pressure sensors and gauges installed in conjunction with gas appliances or equipment installed in accordance with manufacturer's instructions.

404.16 Location of outlets.

The unthreaded portion of piping outlets shall extend not less than l inch (25.4 mm) through finished ceilings and walls and where extending through floors or outdoor patios and slabs, shall be not less than 2 inches (50.8 mm) above them. The outlet fitting or piping shall be securely supported. Outlets shall not be placed behind doors. Outlets shall be located in the room or space where the appliance is installed.

Exception: Listed and labeled flush-mounted-type quick-disconnect devices and listed and labeled gas convenience outlets shall be installed in accordance with the manufacturer's instructions.

404.17 Reserved.

404.18 Pipe cleaning.

The use of a flammable or combustible gas to clean or remove debris from the interior of a piping system shall be prohibited.

404.19 Prohibited devices.

A device shall not be placed inside the piping or fittings that will reduce the cross-sectional area or otherwise obstruct the free flow of gas.

Exceptions:

1. Approved gas filters.

2. An approved fitting or device where the gas piping system has been sized to accommodate the pressure drop of the fitting or device.

3. Approved gas meters for monitoring and analysis of gas usage.

404.20 Testing of piping.

Before any system of piping is put in service, it shall be tested to ensure that it is gas tight. Testing, inspection and purging of piping systems shall comply with Section 406.

404.21 Qualifications for gas work.

Gas work shall be performed by individuals possessing the qualifications set forth in Article 28-423 of the Administrative Code. Welders must be qualified in accordance with Section 404.21.1.

404.21.1 Welder's qualifications.

Welders installing gas piping within buildings at any pressure shall comply with the following:

1. Welders shall be qualified for all pipe sizes, wall thicknesses and all positions in accordance with the ASME Boiler and Pressure Vessel Code, Section IX. Requalification of welders is required on an annual basis and when requested by the commissioner.

2. Welder qualification testing shall be performed by an approved agency and the inspector witnessing the test shall be an authorized AWS Certified Welding Inspector. Radiographic test specimens shall be evaluated by a radiographic inspector having a minimum radiography qualification of Level II in accordance with the ASNT, Document No. SNT-TC-1A, Supplement A.

3. Copies of the certified welder qualification reports shall be maintained by both the approved agency and the licensed master plumber employing the welder(s) for at least six years and shall be made available to the department upon request.

4. The approved agency shall submit certified welder qualification reports to the department upon successful qualification of a welder and when requested by the commissioner.

5. The licensed master plumber employing the welder(s) shall submit a statement to the department including who welded the gas piping along with a copy(s) of the certified welder qualification report(s) witnessed by a representative of the licensed master plumber, at the time of the first roughing inspection.

6. Requalification of a welder is required should the welder fail to maintain welder's continuity every six months. The licensed master plumber employing the welder shall maintain a welder continuity log and the log shall be made available to the department upon request.

404.21.2 Welding requirements.

All gas distribution piping to customer appliances operating in excess of 1/2 psig (3.5 kPa gauge) shall be welded.

404.21.3 Welding records.

The licensed master plumber employing the welder(s) shall assign to each welder an identification symbol or number to identify the welds performed by that particular welder. The welder shall identify all welds with his or her symbol or number. The licensed master plumber shall maintain records identifying the weld(s) made by each welder for at least six years and shall make such records available to the department upon request.