ADOPTS WITH AMENDMENTS:

UPC 2018

Heads up: There are no amended sections in this chapter.
The regulations of this chapter shall govern the installation of fuel gas piping in or in connection with a building, structure or within the property lines of premises up to 5 pounds-force per square inch (psi) (34 kPa) for natural gas and 10 psi (69 kPa) for undiluted propane, other than service pipe. Fuel oil piping systems shall be installed in accordance with NFPA 31.
Coverage of piping systems shall extend from the point of delivery to the appliance connections. For other than undiluted liquefied petroleum gas (LP-Gas) systems, the point of delivery shall be the outlet of the service meter assembly or the outlet of the service regulator or service shutoff valve where no meter is provided. For undiluted LP-Gas systems, the point of delivery shall be considered to be the outlet of the final pressure regulator, exclusive of line gas regulators where no meter is installed. Where a meter is installed, the point of delivery shall be the outlet of the meter. [NFPA 54:1.1.1.1 (A)]
Requirements for piping systems shall include design, materials, components, fabrication, assembly, installation, testing, inspection, operation, and maintenance. [NFPA 54:1.1.1.1(C)]
This code shall not apply to the following items (reference standards for some of which appear in Chapter 17):
  1. Portable LP-Gas appliances and equipment of all types that are not connected to a fixed fuel piping system.
  2. Installation of appliances such as brooders, dehydrators, dryers, and irrigation equipment used for agricultural purposes.
  3. Raw material (feedstock) applications except for piping to special atmosphere generators.
  4. Oxygen-fuel gas cutting and welding systems.
  5. Industrial gas applications using such gases as acetylene and acetylenic compounds, hydrogen, ammonia, carbon monoxide, oxygen, and nitrogen.
  6. Petroleum refineries, pipeline compressor or pumping stations, loading terminals, compounding plants, refinery tank farms, and natural gas processing plants.
  7. Large integrated chemical plants or portions of such plants where flammable or combustible liquids or gases are produced by chemical reactions or used in chemical reactions.
  8. LP-Gas installations at utility gas plants.
  9. Liquefied natural gas (LNG) installations.
  10. Fuel gas piping in electric utility power plants.
  11. Proprietary items of equipment, apparatus, or instruments such as gas-generating sets, compressors, and calorimeters.
  12. LP-Gas equipment for vaporization, gas mixing, and gas manufacturing.
  13. LP-Gas piping for buildings under construction or renovations that is not to become part of the permanent building piping system—that is, temporary fixed piping for building heat.
  14. Installation of LP-Gas systems for railroad switch heating.
  15. Installation of LP-Gas and compressed natural gas (CNG) systems on vehicles.
  16. Gas piping, meters, gas-pressure regulators, and other appurtenances used by the serving gas supplier in distribution of gas, other than undiluted LP-Gas.
  17. Building design and construction, except as specified herein.
  18. Fuel gas systems on recreational vehicles manufactured in accordance with NFPA 1192.
  19. Fuel gas systems using hydrogen as a fuel.
  20. Construction of appliances. [NFPA 54:1.1.1.2]
Upon completion of the installation, alteration, or repair of gas piping, and prior to the use thereof, the Authority Having Jurisdiction shall be notified that such gas piping is ready for inspection.
Excavations required for the installation of underground piping shall be kept open until the piping has been inspected and approved. Where such piping is covered or concealed before such approval, it shall be exposed upon the direction of the Authority Having Jurisdiction.
The Authority Having Jurisdiction shall make the following inspections and either shall approve that portion of the work as completed or shall notify the permit holder wherein the same fails to be in accordance with this code.
This inspection shall be made after gas piping authorized by the permit has been installed and before such piping has been covered or concealed or fixture or appliance has been attached thereto. This inspection shall include a determination that the gas piping size, material, and installation meet the requirements of this code.
This inspection shall be made after piping authorized by the permit has been installed, and after portions, thereof that are to be covered or concealed are so concealed, and before fixture, appliance, or shutoff valve has been attached thereto. This inspection shall comply with Section 1213.1. Test gauges used in conducting tests shall be in accordance with Section 318.0.
In cases where the work authorized by the permit consists of a minor installation of additional piping to piping already connected to a gas meter, the preceding inspections shall be permitted to be waived at the discretion of the Authority Having Jurisdiction. In this event, the Authority Having Jurisdiction shall make such inspection as deemed advisable to be assured that the work has been performed in accordance with the intent of this code.
Whereupon final piping inspection, the installation is found to be in accordance with the provisions of this code, a certificate of inspection shall be permitted to be issued by the Authority Having Jurisdiction.
A copy of the certificate of such final piping inspection shall be issued to the serving gas supplier supplying gas to the premises.
It shall be unlawful for a serving gas supplier, or person is furnishing gas, to turn on or cause to be turned on, a fuel gas or a gas meter or meters, until such certificate of final inspection, as herein provided, has been issued.
It shall be unlawful for a person, firm, or corporation, excepting an authorized agent or employee of a person, firm, or corporation engaged in the business of furnishing or supplying gas and whose service pipes supply or connect with the particular premises, to turn on or reconnect gas service in or on a premises where and when gas service is, at the time, not being rendered.
It shall be unlawful to turn on or connect gas in or on the premises unless outlets are securely connected to gas appliances or capped or plugged with screw joint fittings.
The Authority Having Jurisdiction or the serving gas supplier is hereby authorized to disconnect gas piping or appliance or both that shall be found not to be in accordance with the requirements of this code or that are found defective and in such condition as to endanger life or property.
Where such disconnection has been made, a notice shall be attached to such gas piping or appliance or both that shall state the same has been disconnected, together with the reasons thereof.
It shall be unlawful to remove or disconnect gas piping or gas appliance without capping or plugging with a screw joint fitting, the outlet from which said pipe or appliance was removed. Outlets to which gas appliances are not connected shall be left capped and gastight on a piping system that has been installed, altered, or repaired.

Exception: Where an approved listed quick-disconnect device is used.

Where temporary use of gas is desired, and the Authority Having Jurisdiction deems the use necessary, a permit shall be permitted to be issued for such use for a period not to exceed that designated by the Authority Having Jurisdiction, provided that such gas piping system otherwise is in accordance with the requirements of this code regarding material, sizing, and safety.
Where required by the Authority Having Jurisdiction, a piping sketch or plan shall be prepared before proceeding with the installation. The plan shall show the proposed location of piping, the size of different branches, the various load demands, and the location of the point of delivery. [NFPA 54:5.1.1]
When additional appliances are being connected to a gas piping system, the existing piping shall be checked to determine whether it has adequate capacity. If inadequate, the existing system shall be enlarged as required, or separate gas piping of adequate capacity shall be provided. [NFPA 54:5.1.2.1 — 5.1.2.2]
The location of the point of delivery shall be acceptable to the serving gas supplier. [NFPA 54:5.2]
Where two or more meters, or two or more service regulators where meters are not provided, are located on the same premises and supply separate users, the gas piping systems shall not be interconnected on the outlet side of the meters or service regulators. [NFPA 54:5.3.1]
Where a supplementary gas for standby use is connected downstream from a meter or a service regulator where a meter is not provided, equipment to prevent backflow shall be installed. A three-way valve installed to admit the standby supply, and at the same time shut off the regular supply, shall be permitted to be used for this purpose. [NFPA 54:5.3.2.1 — 5.3.2.2]
Gas piping systems shall be of such size and so installed as to provide a supply gas sufficient to meet the maximum demand and supply gas to each appliance inlet at not less than the minimum supply pressure required by the appliance. [NFPA 54:5.4.1]
The volumetric flow rate of gas to be provided shall be the sum of the maximum inputs of the appliances served. The volumetric flow rate of gas to be provided shall be adjusted for altitude where the installation is above 2000 feet (610 m). [NFPA 54:5.4.2.1 — 5.4.2.2]. Where the input rating is not indicated, the gas supplier, appliance manufacturer, or a qualified agency shall be contacted, or the rating from Table 1208.4.1 shall be used for estimating the volumetric flow rate of gas to be supplied.

TABLE 1208.4.1
APPROXIMATE GAS INPUT FOR TYPICAL APPLIANCES [NFPA 54: TABLE A.5.4.2.1]

APPLIANCE INPUT
(Btu/h approx.)
Space Heating Units
Warm air furnace
Single family 100 000
Multifamily, per unit 60 000
Hydronic boiler
Single family 100 000
Multifamily, per unit 60 000
Space and Water Heating Units
Hydronic boiler
Single-family 120 000
Multifamily, per unit 75 000
Water Heating Appliances
Water heater, automatic storage
30 to 40 gallon tank 35 000
Water heater, automatic storage
50 gallon tank 50 000
Water heater, automatic instantaneous
Capacity at 2 gallons per minute 142 800
Capacity at 4 gallons per minute 285 000
Capacity at 6 gallons per minute 428 400
Water heater, domestic, circulating or side-arm 35 000
Cooking Appliances
Range, freestanding, domestic 65 000
Built-in oven or broiler unit, domestic 25 000
Built-in top unit, domestic 40 000
Other Appliances
Refrigerator 3000
Clothes dryer, Type 1 (domestic) 35 000
Gas fireplace direct vent 40 000
Gas log 80 000
Barbecue 40 000
Gaslight 2500

For SI units: 1000 British thermal units per hour = 0.293 kW

The total connected hourly load shall be used as the basis for piping sizing, assuming all the appliances are operating at full capacity simultaneously.

Exception: Sizing shall be permitted to be based upon established load diversity factors. [NFPA 54:5.4.2.3]

Gas piping shall be sized in accordance with one of the following:
  1. Pipe sizing tables or sizing equations in this chapter.
  2. Other approved engineering methods acceptable to the Authority Having Jurisdiction.
  3. Sizing tables included in a listed piping system manufacturer's installation instructions. [NFPA 54:5.4.3]
The design pressure loss in any piping system under maximum probable flow conditions, from the point of delivery to the inlet connection of the appliance, shall be such that the supply pressure at the appliance is greater than or equal to the minimum pressure required by the appliance. [NFPA 54:5.4.4]
The maximum design operating pressure for piping systems located inside buildings shall not exceed 5 psi (34 kPa) unless one or more of the following conditions are met:
  1. The piping system is welded.
  2. The piping is located in a ventilated chase or otherwise enclosed for protection against accidental gas accumulation.
  3. The piping is located inside buildings or separate areas of buildings used exclusively for one of the following:
    1. Industrial processing or heating
    2. Research
    3. Warehousing
    4. Boiler or mechanical rooms
  4. The piping is a temporary installation for buildings under construction.
  5. The piping serves appliances or equipment used for agricultural purposes.
  6. The piping system is an LP-Gas piping system with a design operating pressure greater than 20 psi (138 kPa) and complies with NFPA 58. [NFPA 54:5.5.1]
LP-Gas systems designed to operate below -5°F (-21°C) or with butane or a propane-butane mix shall be designed to either accommodate liquid LP-Gas or to prevent LP-Gas vapor from condensing back into a liquid. [NFPA 54:5.5.2]
Materials used for piping systems shall either comply with the requirements of this chapter or be acceptable to the Authority Having Jurisdiction. [NFPA 54:5.6.1.1]
Pipe, fittings, valves, or other materials shall not be used again unless they are free of foreign materials and have been ascertained to be approved for the service intended. [NFPA 54:5.6.1.2]
Material not covered by the standards specifications listed herein shall meet the following criteria:
  1. Be investigated and tested to determine that it is safe and suitable for the proposed service.
  2. Be recommended for that service by the manufacturer.
  3. Be acceptable to the Authority Having Jurisdiction. [NFPA 54:5.6.1.3]
Cast-iron pipe shall not be used. [NFPA 54:5.6.2.1]
Steel and wrought-iron pipe shall be at least of standard weight (Schedule 40) and shall comply with one of the following standards:
  1. ASME B36.10
  2. ASTMA53
  3. ASTMA106 [NFPA 54:5.6.2.2]
Copper and copper alloy pipe shall not be used if the gas contains more than an average of 0.3 grains of hydrogen sulfide per 100 standard cubic feet (scf) of gas (0.7 mg/100 L).

Threaded copper, copper alloy, or aluminum alloy pipe shall not be used with gases corrosive to such material. [NFPA 54:5.6.2.3 — 5.6.2.4]

Aluminum alloy pipe shall comply with ASTM B241 (except that the use of alloy 5456 is prohibited) and shall be marked at each end of each length indicating compliance. Aluminum alloy pipe shall be coated to protect against external corrosion where it is in contact with masonry, plaster, insulation or is subject to repeated wettings by such liquids as water, detergents, or sewage. [NFPA 54:5.6.2.5]

Aluminum alloy pipe shall not be used in exterior locations or underground. [NFPA 54:5.6.2.6]

Seamless copper, aluminum alloy, or steel tubing shall not be used with gases corrosive to such material. [NFPA 54:5.6.3]
Steel tubing shall comply with ASTM A254. [NFPA 54:5.6.3.1]
Copper and copper alloy tubing shall not be used where the gas contains more than an average of 0.3 grains of hydrogen sulfide per 100 scf of gas (0.7 mg/100 L). Copper tubing shall comply with standard Type K or L of ASTM B88 or ASTM B280. [NFPA 54:5.6.3.2]
Aluminum alloy tubing shall comply with ASTM B210 or ASTM B241. Aluminum alloy tubing shall be coated to protect against external corrosion where it is in contact with masonry, plaster, insulation, or is subject to repeated wettings by such liquids as water, detergent, or sewage. Aluminum alloy tubing shall not be used in exterior locations or underground. [NFPA 54:5.6.3.3]
Corrugated stainless steel tubing shall be listed in accordance with CSA LC-1. [NFPA 54:5.6.3.4]
Polyethylene plastic pipe, tubing, and fittings used to supply fuel gas shall conform to ASTM D2513. Pipe to be used shall be marked "gas" and "ASTM D2513." Polyvinyl chloride (PVC) and chlorinated polyvinyl chloride (CPVC) plastic pipe, tubing, and fittings shall not be used to supply fuel gas. [NFPA 54:5.6.4.1.1 — 5.6.4.1.3]
Plastic pipe and fittings used to connect regulator vents to remote vent terminations shall be PVC conforming to UL 651(Schedule 40 and 80). PVC vent piping shall not be installed indoors. [NFPA 54:5.6.4.2]
Anodeless risers shall comply with the following:
  1. Factory-assembled anodeless risers shall be recommended by the manufacturer for the gas used and shall be leak-tested by the manufacturer in accordance with written procedures.
  2. Service head adapters and field-assembled anodeless risers incorporating service head adapters shall be recommended by the manufacturer for the gas used and shall be design-certified to be in accordance with the requirements of Category I of ASTM D2513. The manufacturer shall provide the user qualified installation instructions.
  3. The use of plastic pipe, tubing, and fittings in undiluted LP-Gas piping systems shall be in accordance with NFPA 58. [NFPA 54:5.6.4.3(3)]
Gas pipe, tubing, and fittings shall be clear and free from cutting burrs and defects in structure or threading, and shall be thoroughly brushed and chip and scale blown. Defects in pipe, tubing, and fittings shall not be repaired. Defective pipe, tubing, and fittings shall be replaced. [NFPA 54:5.6.5]
Where in contact with material or atmosphere exerting a corrosive action, metallic piping and fittings coated with a corrosion-resistant material shall be used. External or internal coatings or linings used on piping or components shall not be considered as adding strength. [NFPA 54:5.6.6]
Metallic pipe and fitting threads shall be taper pipe threads and shall comply with ASME Bl.20.1. [NFPA 54:5.6.7.1]
Pipe with threads that are stripped, chipped, corroded, or otherwise damaged shall not be used. Where a weld opens during the operation of cutting or threading, that portion of the pipe shall not be used. [NFPA 54:5.6.7.2]
Field threading of metallic pipe shall be in accordance with Table 1208.6.10.2. [NFPA 54:5.6.7.3]

TABLE 1208.6.10.2
SPECIFICATIONS FOR THREADING METALLIC PIPE
[NFPA 54: TABLE 5.6.73]

IRON PIPE SIZE
(inches)
APPROXIMATE LENGTH OF THREADED PORTION
(inches)
APPROXIMATE NUMBER OF THREADS TO BE CUT
1/2 3/4 10
3/4 3/4 10
1 7/8 10
11/4 1 11
11/2 1 11
2 1 11
21/2 11/2 12
3 11/2 12
4 15/8 13

For SI units: 1 inch = 25.4 mm

Thread joint compounds shall be resistant to the action of LP-Gas or to any other chemical constituents of the gases to be conducted through the piping. [NFPA 54:5.6.7.4]
The type of piping joint used shall be suitable for the pressure and temperature conditions and shall be selected giving consideration to joint tightness and mechanical strength under the service conditions. The joint shall be able to sustain the maximum end force due to the internal pressure and any additional forces due to temperature expansion or contraction, vibration, fatigue, or the weight of the pipe and its contents. [NFPA 54:5.6.8]
Pipe joints shall be threaded, flanged, brazed, welded, or press-connect fittings that comply with CSA LC-4. Where nonferrous pipe is brazed, the brazing materials shall have a melting point in excess of 1000°F (538°C). Brazing alloys shall not contain more than 0.05 percent phosphorus. [NFPA 54:5.6.8.1]
Tubing joints shall be made with approved gas tubing fittings, be brazed with a material having a melting point in excess of 1000°F (538°C), or made by press-connect fittings that comply with CSA LC-4. Brazing alloys shall not contain more than 0.05 percent phosphorus. [NFPA 54:5.6.8.2]
Flared joints shall be used only in systems constructed from nonferrous pipe and tubing where experience or tests have demonstrated that the joint is approved for the conditions and where provisions are made in the design to prevent separation of the joints. [NFPA 54:5.6.8.3]
Metallic pipe fittings shall comply with the following:
  1. Threaded fittings in sizes larger than 4 inches (100 mm) shall not be used unless approved by the Authority Having Jurisdiction.
  2. Fittings used with steel or wrought-iron pipe shall be steel, copper alloy, malleable iron, or cast-iron.
  3. Fittings used with copper or copper alloy pipe shall be copper or copper alloy.
  4. Fittings used with aluminum alloy pipe shall be of aluminum alloy.
  5. Cast-iron fittings shall comply with the following:
    1. Flanges shall be permitted.
    2. Bushings shall not be used.
    3. Fittings shall not be used in systems containing flammable gas-air mixtures.
    4. Fittings in sizes 4 inches (100 mm) and larger shall not be used indoors unless approved by the Authority Having Jurisdiction.
    5. Fittings in sizes 6 inches (150 mm) and larger shall not be used unless approved by the Authority Having Jurisdiction.
  6. Aluminum alloy fitting threads shall not form the joint seal.
  7. Zinc-aluminum alloy fittings shall not be used in systems containing flammable gas-air mixtures.
  8. Special fittings such as couplings; proprietary-type joints; saddle tees; gland-type compression fittings; and flared, flareless, or compression-type tubing fittings shall be as follows:
    1. Used within the fitting manufacturer's pressure-temperature recommendations.
    2. Used within the service conditions anticipated with respect to vibration, fatigue, thermal expansion, or contraction.
    3. Installed or braced to prevent separation of the joint by gas pressure or external physical damage.
    4. Approved by the Authority Having Jurisdiction. [NFPA 54:5.6.8.4 (1-8)]
Plastic pipe, tubing, and fittings shall be installed in accordance with the manufacturer's installation instructions. Section 1208.6.12.1 through Section 1208.6.12.4 shall be observed where making such joints. [NFPA 54:5.6.9]
The joint shall be designed and installed so that the longitudinal pull-out resistance of the joint will be at least equal to the tensile strength of the plastic piping material. [NFPA 54:5.6.9(1)]
Heat-fusion joints shall be made in accordance with qualified procedures that have been established and proven by test to produce gastight joints as strong as the pipe or tubing being joined. Joints shall be made with the joining method recommended by the pipe manufacturer. Heat-fusion fittings shall be marked "ASTM D2513." [NFPA 54:5.6.9(2)]
Where compression-type mechanical joints are used, the gasket material in the fitting shall be compatible with the plastic piping and with the gas distributed by the system. An internal tubular rigid stiffener shall be used in conjunction with the fitting. The stiffener shall be flush with the end of the pipe or tubing and shall extend not less than the outside end of the compression fitting where installed. The stiffener shall be free of rough or sharp edges and shall not be a forced fit in the plastic. Split tubular stiffeners shall not be used. [NFPA 54:5.6.9(3)]
Plastic piping joints and fittings for use in LP-Gas piping systems shall be in accordance with NFPA 58. [NFPA 54:5.6.9(4)]
Cast iron flanges shall be in accordance with ASME B16.1. [NFPA 54:5.6.10.1.1]
Steel flanges shall be in accordance with the following:
  1. ASME B16.5 or
  2. ASME B16.47. [NFPA 54:5.6.10.1.2]
Non-ferrous flanges shall be in accordance with ASME B 16.24. [NFPA 54:5.6.10.1.3]
Ductile iron flanges shall be in accordance with ASME B 16.42. [NFPA 54:5.6.10.1.4]
Raised-face flanges shall not be joined to flat-faced cast iron, ductile iron or nonferrous material flanges. [NFPA 54:5.6.10.2]
Standard facings shall be permitted for use under this code. Where 150 psi (1034 kPa) steel flanges are bolted to Class 125 cast-iron flanges, the raised face on the steel flange shall be removed. [NFPA 54:5.6.10.3]
Lapped flanges shall be used only aboveground or in exposed locations accessible for inspection. [NFPA 54:5.6.10.4]
The material for gaskets shall be capable of withstanding the design temperature and pressure of the piping system and the chemical constituents of the gas being conducted without change to its chemical and physical properties. The effects of fire exposure to the joint shall be considered in choosing the material. [NFPA 54:5.6.11]
Acceptable materials shall include the following:
  1. Metal (plain or corrugated)
  2. Composition
  3. Aluminum o-rings
  4. Spiral-wound metal gaskets
  5. Rubber-faced phenolic
  6. Elastomeric [NFPA 54:5.6.11.1]
Metallic flange gaskets shall be in accordance with ASME B16.20. [NFPA 54:5.6.11.2.1]
Non-metallic flange gaskets shall be in accordance with ASME B16.21. [NFPA 54:5.6.11.2.2]
Full-face flange gaskets shall be used with all non-steel flanges. [NFPA 54:5.6.11.3]
When a flanged joint is separated, the gasket shall be replaced. [NFPA 54:5.6.11.2.4]
Gas meters shall be selected for the maximum expected pressure and permissible pressure drop. [NFPA 54:5.7.1]
Gas meters shall be located in ventilated spaces readily accessible for examination, reading, replacement, or necessary maintenance. [NFPA 54:5.7.2.1]
Gas meters shall not be placed where they will be subjected to damage, such as adjacent to a driveway; under a fire escape; in public passages, halls, or where they will be subject to excessive corrosion or vibration. [NFPA 54:5.7.2.2]
Gas meters shall not be located where they will be subjected to extreme temperatures or sudden extreme changes in temperature or in areas where they are subjected to temperatures beyond those recommended by the manufacturer. [NFPA 54:5.7.2.3]
Gas meters shall be supported or connected to rigid piping so as not to exert a strain on the meters. Where flexible connectors are used to connect a gas meter to downstream piping at mobile homes in mobile home parks, the meter shall be supported by a post or bracket placed in a firm footing or by other means providing equivalent support. [NFPA 54:5.7.3]
Meters shall be protected against overpressure, backpressure, and vacuum. [NFPA 54:5.7.4]
Gas piping at multiple meter installations shall be marked by a metal tag or other permanent means designating the building or the part of the building being supplied and attached by the installing agency. [NFPA 54:5.7.5]
A line pressure regulator or gas appliance pressure regulator, as applicable, shall be installed where the gas supply pressure exceeds that at which the branch supply line or appliances are designed to operate or vary beyond design pressure limits. [NFPA 54:5.8.1]
Line pressure regulators shall be listed in accordance with CSA Z21.80. [NFPA 54:5.8.2]
The gas pressure regulator shall be accessible for servicing. [NFPA 54:5.8.3]
Pressure regulators shall be protected against physical damage. [NFPA 54:5.8.4]
Line pressure regulators shall comply with all of the following:
  1. An independent vent to the exterior of the building, sized in accordance with the regulator manufacturer's instructions, shall be provided where the location of a regulator is such that a ruptured diaphragm will cause a hazard. Where more than one regulator is at a location, each regulator shall have a separate vent to the outdoors or, if approved by the Authority Having Jurisdiction, the vent lines shall be permitted to be manifolded in accordance with accepted engineering practices to minimize backpressure in the event of diaphragm failure. Materials for vent piping shall be in accordance with Section 1208.6 through Section 1208.6.12.3.
    Exception: A regulator and vent limiting means combination listed as complying with CSA Z21.80 shall be permitted to be used without a vent to the outdoors.
  2. The vent shall be designed to prevent the entry of water, insects, or other foreign materials that could cause a blockage.
  3. The regulator vent shall terminate at least 3 feet (914 mm) from a source of ignition.
  4. At locations where regulators might be submerged during floods, a special antiflood-type breather vent fitting shall be installed, or the vent line shall be extended above the height of the expected flood waters.
  5. A regulator shall not be vented to the appliance flue or exhaust system. [NFPA 54:5.8.5.1]
For venting of gas appliance pressure regulators see Section 507.21. [NFPA 54:5.8.5.2]
The discharge of vents shall be in accordance with the following requirements:
  1. The discharge stacks, vents, or outlet parts of all pressure-relieving and pressure-limiting devices shall be located so that gas is safely discharged to the outdoors. Discharge stacks or vents shall be designed to prevent the entry of water, insects, or other foreign material that could cause a blockage.
  2. The discharge stack or vent line shall be at least the same size as the outlet of the pressure-relieving device. [NFPA 54:5.9.8.1 — 5.9.8.2]
Valved and regulated bypasses shall be permitted to be placed around gas line pressure regulators where continuity of service is imperative. [NFPA 54:5.8.6]
Line pressure regulators at multiple regulator installations shall be marked by a metal tag or other permanent means designating the building or the part of the building being supplied. [NFPA 54:5.8.7]
Where the serving gas supplier delivers gas at a pressure greater than 2 psi (14 kPa) for piping systems serving appliances designed to operate at a gas pressure of 14 inches water column (3.5 kPa) or less, overpressure protection devices shall be installed. Piping systems serving equipment designed to operate at inlet pressures greater than 14 inches water column (3.5 kPa) shall be equipped with overpressure protection devices as required by the appliance manufacturer's installation instructions. [NFPA 54:5.9.1]
Where piping systems serving appliances designed to operate with a gas supply pressure of 14 inches water column (3.5 kPa) or less are required to be equipped with overpressure protection by Section 1208.9, each overpressure protection device shall be adjusted to limit the gas pressure to each connected appliance to 2 psi (14 kPa) or less upon a failure of the line pressure regulator. [NFPA 54:5.9.2.1]
Where piping systems serving appliances designed to operate with a gas supply pressure greater than 14 inches water column (3.5 kPa) are required to be equipped with overpressure protection by Section 1208.9, each over-pressure protection device shall be adjusted to limit the gas pressure to each connected appliance as required by the appliance manufacturer's installation instructions. [NFPA 54:5.9.2.2]
Each overpressure protection device installed to meet the requirements of this section shall be capable of limiting the pressure to its connected appliance(s) as required by this section independently of any other pressure control equipment in the piping system. [NFPA 54:5.9.2.3]
Each gas piping system for which an overpressure protection device is required by this section shall be designed and installed so that a failure of the primary pressure control device(s) is detectable. [NFPA 54:5.9.2.4]
If a pressure relief valve is used to meet the requirements of this section, it shall have a flow capacity such that the pressure in the protected system is maintained at or below the limits specified in Section 1208.10 under the following conditions:
  1. The line pressure regulator for which the relief valve is providing overpressure protection has failed wide open.
  2. The gas pressure at the inlet of the line pressure regulator for which the relief valve is providing over-pressure protection is not less than the regulator's normal operating inlet pressure. [NFPA 54:5.9.2.5]
Protective devices shall be installed as close to the equipment as practical where the design of the equipment connected is such that air, oxygen, or standby gases are capable of being forced into the gas supply system.

Gas and air combustion mixers incorporating double diaphragm "zero" or "atmosphere" governors or regulators shall require no further protection unless connected directly to compressed air or oxygen at pressures of 5 psi (34 kPa) or more. [NFPA 54:5.10.1.1 — 5.10.1.2]

Protective devices shall include, but not be limited to the following:
  1. Check valves.
  2. Three-way valves (of the type that completely closes one side before starting to open the other side).
  3. Reverse flow indicators controlling positive shutoff valves.
  4. Normally closed air-actuated positive shutoff pressure regulators. [NFPA 54:5.10.2]
A protective device shall be installed between the meter and the appliance or equipment if the operation of the appliance or equipment is such that it could produce a vacuum or a dangerous reduction in gas pressure at the meter. Such protective devices include, but are not limited to, mechanical, diaphragm-operated, or electrically operated low-pressure shutoff valves. [NFPA 54:5.11]
Shutoff valves shall be approved and shall be selected giving consideration to pressure drop, service involved, emergency use, and reliability of operation. Shutoff valves of size 1 inch (25 mm) National Pipe Thread and smaller shall be listed. [NFPA 54:5.12]
Piping systems shall be designed to prevent failure from thermal expansion or contraction. [NFPA 54:5.14.1]
Where local conditions include earthquake, tornado, unstable ground, or flood hazards, special consideration shall be given to increased strength and flexibility of piping supports and connections. [NFPA 54:5.14.2]
Where automatic excess flow valves are installed, they shall be listed to CSA Z21.93 and shall be sized and installed in accordance with the manufacturer's instructions. [NFPA 54:5.13]
Underground gas piping shall be installed with sufficient clearance from any other underground structure to avoid contact therewith, to allow maintenance, and to protect against damage from proximity to other structures. In addition, underground plastic piping shall be installed with sufficient clearance or shall be insulated from sources of heat to prevent the heat from impairing the serviceability of the pipe. [NFPA 54:7.1.1]
Underground piping systems shall be installed with a minimum of 12 inches (305 mm) of cover. The minimum cover shall be increased to 18 inches (457 mm) if external damage to the pipe or tubing from external forces is likely to result. Where a minimum of 12 inches (305 mm) of cover cannot be provided, the pipe shall be installed in conduit or bridged (shielded). [NFPA 54:7.1.2.1 (A) (B)]
The trench shall be graded so that the pipe has a firm, substantially continuous bearing on the bottom of the trench. [NFPA 54:7.1.2.2]
Where flooding of the trench is done to consolidate the backfill, care shall be exercised to see that the pipe is not floated from its firm bearing on the trench bottom. [NFPA 54:7.1.2.3]
Steel pipe and steel tubing installed underground shall be installed in accordance with Section 1210.1.3.1 through Section 1210.1.3.9. [NFPA 54:7.1.3]
Zinc coating (galvanizing) shall not be deemed adequate protection for underground gas piping. [NFPA 54:7.1.3.1]
Underground piping shall comply with one or more of the following unless approved technical justification is provided to demonstrate that protection is unnecessary:
  1. The piping shall be made of a corrosion-resistant material that is suitable for the environment in which it will be installed.
  2. Pipe shall have a factory-applied, electrically insulating coating. Fittings and joints between sections of coated pipe shall be coated in accordance with the coating manufacturer's instructions.
  3. The piping shall have a cathodic protection system installed, and the system shall be maintained in accordance with Section 1210.1.3.3 or Section 1210.1.3.6. [NFPA 54:7.1.3.2]
Cathodic protection systems shall be monitored by testing, and the results shall be documented. The test results shall demonstrate one of the following:
  1. A pipe-to-soil voltage of —0.85 volts or more negative is produced, with reference to a saturated copper-copper sulfate half cell.
  2. A pipe-to-soil voltage of —0.78 volts or more negative is produced, with reference to a saturated K.C1 calomel half cell.
  3. A pipe-to-soil voltage of —0.80 volts or more negative is produced, with reference to a silver-silver chloride half cell.
  4. Compliance with a method described in Appendix D of Title 49 of the code of Federal Regulations, Part 192. [NFPA 54:7.1.3.3]
Sacrificial anodes shall be tested in accordance with the following:
  1. Upon installation of the cathodic protection system, except where prohibited by climatic conditions, in which case the testing shall be performed not later than 180 days after the installation of the system.
  2. 12 to 18 months after the initial test.
  3. Upon successful verification testing in accordance with Section 1210.1.3.4(1) and Section 1210.1.3.4(2), periodic follow-up testing shall be performed at intervals not to exceed 36 months. [NFPA 54:7.1.3.4]
Systems failing a test shall be repaired not more than 180 days after the date of the failed testing. The testing schedule shall be restarted as required in Section 1210.1.3.4(1) and Section 1210.1.3.4(2), and the results shall comply with Section 1210.1.3.3. [NFPA 54:7.1.3.5]
Impressed current cathodic protection systems shall be inspected and tested in accordance with the following schedule:
  1. The impressed current rectifier voltage output shall be checked at intervals not exceeding two months.
  2. The pipe-to-soil voltage shall be tested at least annually. [NFPA 54:7.1.3.6]
Documentation of the results of the two most recent tests shall be retained. [NFPA 54:7.1.3.7]
Where dissimilar metals are joined underground, an insulating coupling or fitting shall be used. [NFPA 54:7.1.3.8]
Steel risers, other than anodeless risers, connected to plastic piping shall be cathodically protected by means of a welded anode. [NFPA 54:7.1.3.9]
Where the formation of hydrates or ice is known to occur, the piping shall be protected against freezing. [NFPA 54:7.1.4]
Underground piping, where installed through the outer foundation or basement wall of a building shall be encased in a protective sleeve or protected by an approved device or method. The space between the gas piping and the sleeve and between the sleeve and the wall shall be sealed to prevent entry of gas and water. [NFPA 54:7.1.5]
Where gas piping is installed underground beneath buildings, the piping shall be either of the following:
  1. Encased in an approved conduit designed to withstand the imposed loads and installed in accordance with Section 1210.1.6.1 or Section 1210.1.6.2.
  2. A piping or encasement system listed for installation beneath buildings. [NFPA 54:7.1.6]
The conduit shall extend into an accessible 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 a gas leakage. Where the end sealing is of a type that retains the full pressure of the pipe, the conduit shall be designed for the same pressure as the pipe. The conduit shall extend at least 4 inches (102 mm) outside the building, be vented outdoors above finished ground level, and be installed to prevent the entrance of water and insects. [NFPA 54:7.1.6.1]
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. [NFPA 54:7.1.6.2]
Plastic piping shall be installed outdoors, underground only.

Exceptions:

  1. Plastic piping shall be permitted to terminate aboveground where an anodeless riser is used.
  2. Plastic piping shall be permitted to terminate with a wall head adapter aboveground in buildings, including basements, where the plastic piping is inserted in a piping material permitted for use in buildings. [NFPA 54:7.1.7.1]
Connections made between metallic and plastic piping shall be made with fittings conforming to one of the following:
  1. ASTM D2513, Category I transition fittings
  2. ASTM F1973
  3. ASTM F2509 [NFPA 54:7.1.7.2]
An electrically continuous corrosion-resistant tracer shall be buried with the plastic pipe to facilitate locating. The tracer shall be one of the following:
  1. A product specifically designed for that purpose.
  2. Insulated copper conductor not less than 14 AWG.

Where tracer wire is used, access shall be provided from aboveground, or one end of the tracer wire or tape shall be brought aboveground at a building wall or riser. [NFPA 54:7.1.7.3 — 7.1.7.3.2]

Piping installed aboveground shall be securely supported and located where it will be protected from physical damage. Where passing through an exterior wall, the piping shall also be protected from corrosion by coating or wrapping with an inert material approved for such applications. The piping shall be sealed around its circumference at the point of the exterior penetration to prevent the entry of water, insects, and rodents. Where piping is encased in a protective pipe sleeve, the annular spaces between the gas piping and the sleeve and between the sleeve and the wall opening shall be sealed. [NFPA 54:7.2.1]
The installation of gas piping shall not cause structural stresses within building components to exceed allowable design limits. Approval shall be obtained before any beams or joists are cut or notched. [NFPA 54:7.2.2.1 — 7.2.2.2]
Piping for other than dry gas conditions shall be sloped not less than 1/4 inch in 15 feet (6.4 mm in 4.6 m) to prevent traps. [NFPA 54:7.2.3]
Gas piping shall be permitted to be installed in accessible spaces between a fixed ceiling and a dropped ceiling, whether or not such spaces are used as a plenum. Valves shall not be located in such spaces.

Exception: Appliance or equipment shutoff valves required by this code shall be permitted to be installed in accessible spaces containing vented appliances.

Gas piping inside any building shall not be installed in or through a clothes chute, chimney or gas vent, dumbwaiter, elevator shaft, or air duct, other than combustion air ducts. [NFPA 54:7.2.4]

Exception: Ducts used to provide ventilation air in accordance with Section 506.0 or to above-ceiling spaces in accordance with Section 1210.2.2.1.

Piping shall be supported with metal pipe hooks, metal pipe straps, metal bands, metal brackets, metal hangers, or building structural components, approved for the size of piping; of adequate strength and quality; and located at intervals to prevent or damp out excessive vibration. Piping shall be anchored to prevent undue strains on connected appliances and equipment and shall not be supported by other piping. Pipe hangers and supports shall conform to the requirements of MSS SP-58. [NFPA 54:7.2.5.1]
Spacing of supports in gas piping installations shall not exceed the distance shown in Table 1210.2.4.1. Spacing of supports for CSST shall be in accordance with the CSST manufacturer's instructions. [NFPA 54:7.2.5.2]

TABLE 1210.2.4.1
SUPPORT OF PIPING
[NFPA 54: TABLE 7.2.5.2]
STEEL PIPE, NOMINAL SIZE OF PIPE
(inches)
SPACING OF SUPPORTS
(feet)
NOMINAL SIZE OF TUBING SMOOTH-WALL
(Inches O.D.)
SPACING OF SUPPORTS
(feet)
1/2 6 1/2 4
3/4 or 1 8 5/8 or 3/4 6
11/4 or larger (horizontal) 10 7/8 or 1 (horizontal) 8
11/4 or larger (vertical) Every floor level 1 or larger (vertical) Every floor level

For SI units: 1 inch = 25 mm, 1 foot = 304.8 mm

Supports, hangers, and anchors shall be installed so as not to interfere with the free expansion and contraction of the piping between anchors. All parts of the supporting system shall be designed and installed, so they are not disengaged by movement of the supported piping. [NFPA 54:7.2.5.3]
Gas piping installed on the roof surfaces shall be elevated above the roof surface and shall be supported in accordance with Table 1210.2.4.1. [NFPA 54:7.2.5.4]
Gas piping in concealed locations shall be installed in accordance with this section. [NFPA 54:7.3.1]
Where gas piping is to be concealed, connections shall be of the following type:
  1. Pipe fittings such as elbows, tees, couplings, and right/left nipple/couplings.
  2. Joining tubing by brazing (see Section 1208.6.11.2).
  3. Fittings listed for use in concealed spaces or that have been demonstrated to sustain, without leakage, forces due to temperature expansion or contraction, vibration, or fatigue based on their geographic location, application, or operation.
  4. Where necessary to insert fittings in the gas pipe that has been installed in a concealed location, the pipe shall be reconnected by welding, flanges, or the use of a right/left nipple/coupling.
Concealed gas piping shall not be located in solid partitions. [NFPA 54:7.3.3]
This provision shall not apply to tubing that pierces walls, floors, or partitions. Tubing installed vertically and horizontally inside hollow walls or partitions without protection along its entire concealed length shall meet the following requirements:
  1. A steel striker barrier not less than 0.0508 of an inch (1.3 mm) thick, or equivalent, is installed between the tubing and the finished wall and extends at least 4 inches (102 mm) beyond concealed penetrations of plates, firestops, wall studs, and similar construction features.
  2. The tubing is installed in single runs and is rigidly secured. [NFPA 54:7.3.4]
In industrial occupancies, gas piping in solid floors such as concrete shall be laid in channels in the floor and covered to permit access to the piping with minimum damage to the building. Where piping in floor channels is exposed to excessive moisture or corrosive substances, the piping shall be protected in an approved manner.

In other than industrial occupancies and where approved by the Authority Having Jurisdiction, gas piping embedded in concrete floor slabs constructed with Portland cement shall be surrounded with a minimum of 11/2 inches (38 mm) of concrete and shall not be in physical contact with other metallic structures such as reinforcing rods or electrically neutral conductors. All piping, fittings, and risers shall be protected against corrosion in accordance with Section 1208.6.9. Piping shall not be embedded in concrete slabs containing quick-set additives or cinder aggregate. [NFPA 54:7.3.5.1 — 7.3.5.2]

Where gas piping exceeding 5 psi (34 kPa) is located within vertical chases in accordance with Section 1208.5(2), the requirements of Section 1210.4.1 through Section 1210.4.3 shall apply. [NFPA 54:7.4]
Where pressure reduction is required in branch connections for compliance with Section 1208.5, such reduction shall take place either inside the chase or immediately adjacent to the outside wall of the chase. Regulator venting and downstream overpressure protection shall comply with Section 1208.8.4 and Section 1208.9 through Section 1208.10.4. The regulator shall be accessible for service and repair, and vented in accordance with one of the following:
  1. Where the fuel gas is lighter than air, regulators equipped with a vent limiting means shall be permitted to be vented into the chase. Regulators not equipped with a vent limiting means shall be permitted to be vented either directly to the outdoors or to a point within the top 1 foot (305 mm) of the chase.
  2. Where the fuel gas is heavier than air, the regulator vent shall be vented only directly to the outdoors. [NFPA 54:7.4.1]
Chase construction shall comply with local building codes with respect to fire resistance and protection of horizontal and vertical openings. [NFPA 54:7.4.2]
A chase shall be ventilated to the outdoors and only at the top. The opening(s) shall have a minimum free area [in square inches (square meters)] equal to the product of one-half of the maximum pressure in the piping [in pounds per square inch (kilopascals)] times the largest nominal diameter of that piping [in inches (millimeters)], or the cross-sectional area of the chase, whichever is smaller. Where more than one fuel gas piping system is present, the free area for each system shall be calculated, and the largest area used. [NFPA 54:7.4.3]
Changes in direction of gas pipe shall be made by the use of fittings, factory bends, or field bends. [NFPA 54:7.5]
Metallic pipe bends shall comply with the following:
  1. Bends shall be made with bending equipment and procedures intended for that purpose.
  2. Bends shall be smooth and free from buckling, cracks, or other evidence of mechanical damage.
  3. The longitudinal weld of the pipe shall be near the neutral axis of the bend.
  4. The pipe shall not be bent through an arc of more than 90 degrees (1.57 rad).
  5. The inside radius of a bend shall be not less than six times the outside diameter of the pipe. [NFPA 54:7.5.1]
Plastic pipe bends shall comply with the following:
  1. The pipe shall not be damaged, and the internal diameter of the pipe shall not be effectively reduced.
  2. Joints shall not be located in pipe bends.
  3. The radius of the inner curve of such bends shall not be less than 25 times the inside diameter of the pipe.
  4. Where the piping manufacturer specifies the use of special bending tools or procedures, such tools or procedures shall be used. [NFPA 54:7.5.2]
Factory-made welding elbows or transverse segments cut therefrom shall have an arc length measured along the crotch at least 1 inch (25.4 mm) for pipe sizes 2 inches (50 mm) and larger. [NFPA 54:7.5.3]
For other than dry gas conditions, a drip shall be provided at a point in the line of pipe where condensate could collect. Where required by the Authority Having Jurisdiction or the serving gas supplier, a drip shall also be provided at the outlet of the meter. This drip shall be so installed as to constitute a trap wherein an accumulation of condensate shuts off the flow of gas before it runs back into the meter. [NFPA 54:7.6.1]
All drips shall be installed only in such locations that they are readily accessible to permit cleaning or emptying. A drip shall not be located where the condensate is likely to freeze. [NFPA 54:7.6.2]
The installation of sediment traps shall be in accordance with Section 1212.9. [NFPA 54:7.6.3]
Outlets shall be located and installed in accordance with the following requirements:
  1. The outlet fittings or piping shall be securely fastened in place.
  2. Outlets shall not be located behind doors.
  3. Outlets shall be located far enough from floors, walls, patios, slabs, and ceilings to permit the use of wrenches without straining, bending, or damaging the piping.
  4. The unthreaded portion of gas piping outlets shall extend not less than 1 inch (25.4 mm) through finished ceilings or indoor or outdoor walls.
  5. The unthreaded portion of gas piping outlets shall extend not less than 2 inches (51 mm) above the surface of floors or outdoor patios or slabs.
  6. The provisions of Section 1210.7(4) and Section 1210.7(5) shall not apply to listed quick-disconnect devices of the flush-mounted type or listed gas convenience outlets. Such devices shall be installed in accordance with the manufacturer's installation instructions. [NFPA 54:7.7.1.1 — 7.7.1.6]
Each outlet, including a valve, shall be closed gastight with a threaded plug or cap immediately after installation and shall be left closed until the appliance or equipment is connected thereto. Where an appliance or equipment is disconnected from an outlet, and the outlet is not to be used again immediately, it shall be capped or plugged gastight.

Exceptions:

  1. Laboratory appliances installed in accordance with Section 1212.3.1 shall be permitted.
  2. The use of a listed quick-disconnect device with integral shutoff or listed gas convenience outlet shall be permitted. [NFPA 54:7.7.2.1]
Appliance shutoff valves installed in fireplaces shall be removed, and the piping capped gastight where the fireplace is used for solid-fuel burning. [NFPA 54:7.7.2.2]
Where a branch outlet is placed on the main supply line before it is known what size pipe will be connected to it, the outlet shall be of the same size as the line that supplies it. [NFPA 54:7.8]
An accessible gas shutoff valve shall be provided upstream of each gas pressure regulator. Where two gas pressure regulators are installed in series in a single gas line, a manual valve shall not be required at the second regulator. [NFPA 54:7.9.1]
Main gas shutoff valves controlling several gas piping systems shall be readily accessible for operation and installed to be protected from physical damage. They shall be marked with a metal tag or other permanent means attached by the installing agency so that the gas piping systems supplied through them are readily identified. [NFPA 54:7.9.2.1]
In multiple-tenant buildings supplied through a master meter, through one service regulator where a meter is not provided, or where meters or service regulators are not readily accessible from the appliance or equipment location, an individual shutoff valve for each apartment or tenant line shall be provided at a convenient point of general accessibility. In a common system serving a number of individual buildings, shutoff valves shall be installed at each building. [NFPA 54:7.9.2.2]
An exterior shutoff valve to permit turning off the gas supply to each building in an emergency shall be provided. The emergency shutoff valves shall be plainly marked as such and their locations posted as required by the Authority Having Jurisdiction. [NFPA 54:7.9.2.3]
Each laboratory space containing two or more gas outlets installed on tables, benches, or in hoods in educational, research, commercial and industrial occupancies shall have a single shutoff valve through which all such gas outlets are supplied. The shutoff valve shall be accessible, located within the laboratory or adjacent to the laboratory's egress door, and identified. [NFPA 54:7.9.2.4]
No device shall be placed inside the gas piping or fittings that reduces the cross-sectional area or otherwise obstructs the free flow of gas, except where an allowance in the piping system design has been made for such a device and where approved by the Authority Having Jurisdiction. [NFPA 54:7.10]
Where gas-air mixing machines are employed to produce mixtures above or below the flammable range, they shall be provided with stops to prevent adjustment of the mixture to within or approaching the flammable range. [NFPA 54:7.11]
Systems containing flammable gas-air mixtures shall be in accordance with Section 1210.12.1 through Section 1210.12.6.
A central premix system with a flammable mixture in the blower or compressor shall consist of the following components:
  1. Gas-mixing machine in the form of an automatic gas-air proportioning device combined with a downstream blower or compressor.
  2. Flammable mixture piping, minimum Schedule 40.
  3. Automatic firecheck(s).
  4. Safety blowout(s) or backfire preventers for systems utilizing flammable mixture lines above 21/2 inches (65 mm) nominal pipe size (NPS) or the equivalent. [NFPA 54:7.12.1]
The following components shall also be permitted to be utilized in any type of central premix system:
  1. Flowmeter(s)
  2. Flame arrester(s) [NFPA 54:7.12.2]
Gas-mixing machines shall have nonsparking blowers and shall be constructed so that a flashback does not rupture machine casings. [NFPA 54:7.12.3]
A mixing blower system shall be limited to applications with minimum practical lengths of mixture piping, limited to a maximum mixture pressure of 10 inches water column (2.5 kPa) and limited to gases containing no more than 10 percent hydrogen. The blower shall be equipped with a gas-control valve at its air entrance arranged so that gas is admitted to the airstream, entering the blower in proper proportions for correct combustion by the type of burners employed, the said gas-control valve being of either the zero governor or mechanical ratio valve type that controls the gas and air adjustment simultaneously. No valves or other obstructions shall be installed between the blower discharge and the burner or burners. [NFPA 54:7.12.4]
Installation of gas-mixing machines shall comply with the following:
  1. The gas-mixing machine shall be located in a well-ventilated area or in a detached building or cutoff room provided with room construction and explosion vents in accordance with sound engineering principles. Such rooms or below-grade installations shall have adequate positive ventilation.
  2. Where gas-mixing machines are installed in well-ventilated areas, the type of electrical equipment shall be in accordance with NFPA 70, for general service conditions unless other hazards in the area prevail. Where gas-mixing machines are installed in small detached buildings or cutoff rooms, the electrical equipment and wiring shall be installed in accordance with NFPA 70 for hazardous locations.
  3. Air intakes for gas-mixing machines using compressors or blowers shall be taken from outdoors whenever practical.
  4. Controls for gas-mixing machines shall include interlocks and a safety shutoff valve of the manual reset type in the gas supply connection to each machine arranged to automatically shut off the gas supply in the event of high or low gas pressure. Except for open-burner installations only, the controls shall be interlocked so that the blower or compressor stops operating following a gas supply failure. Where a system employs pressurized air, means shall be provided to shut off the gas supply in the event of air failure.
  5. Centrifugal gas-mixing machines in parallel shall be reviewed by the user and equipment manufacturer before installation, and means or plans for minimizing the effects of downstream pulsation and equipment overload shall be prepared and utilized as needed. [NFPA 54:7.12.5.1 — 7.12.5.5]
Automatic firechecks and safety blowouts or backfire preventers shall be provided in piping systems distributing flammable air-gas mixtures from gas-mixing machines to protect the piping and the machines in the event of flashback, in accordance with the following:
  1. Approved automatic firechecks shall be installed upstream as close as practical to the burner inlets following the firecheck manufacturer's instructions.
  2. A separate manually operated gas valve shall be provided at each automatic firecheck for shutting off the flow of the gas-air mixture through the firecheck after a flashback has occurred. The valve shall be located upstream as close as practical to the inlet of the automatic firecheck.

    Caution: These valves shall not be reopened after a flashback has occurred until the firecheck has cooled sufficiently to prevent re-ignition of the flammable mixture and has been reset properly.

  3. A safety blowout or backfiring preventer shall be provided in the mixture line near the outlet of each gas-mixing machine where the size of the piping is larger than 2 1/2 inches (65 mm) NPS, or equivalent, to protect the mixing equipment in the event of an explosion passing through an automatic firecheck. The manufacturer's instructions shall be followed when installing these devices, particularly after a disc has burst. The discharge from the safety blowout or backfire preventer shall be located or shielded so that particles from the ruptured disc cannot be directed towards personnel. Wherever there are interconnected installations of gas-mixing machines with safety blowouts or backfire preventers; provision shall be made to keep the mixture from other machines from reaching any ruptured disc opening. Check valves shall not be used for this purpose.
  4. Large-capacity premix systems provided with explosion heads (rupture discs) to relieve excessive pressure in pipelines shall be located at and vented to a safe outdoor location. Provisions shall be provided for automatically shutting off the supply of the gas-air mixture in the event of a rupture. [NFPA 54:7.12.6]
Each aboveground portion of a gas piping system other than CSST that is likely to become energized shall be electrically continuous and bonded to an effective ground-fault current path. Gas piping, other than CSST, shall be considered to be bonded where it is connected to appliances that are connected to the appliance grounding conductor of the circuit supplying that appliance. [NFPA 54:7.13.1]
CSST gas piping systems, and gas piping systems containing one or more segments of CSST, shall be bonded to the electrical service grounding electrode system or, where provided, lightning protection grounding electrode system. [NFPA 54:7.13.2]
The bonding jumper shall connect to a metallic pipe, pipe fitting, or CSST fitting. [NFPA 54:7.13.2.1]
The bonding jumper shall not be smaller than 6 AWG copper wire or equivalent. [NFPA 54:7.13.2.2]
The length of the jumper between the connection to the gas piping system and the grounding electrode system shall not exceed 75 feet (22 875 mm). Any additional electrodes shall be bonded to the electrical service grounding electrode system or, where provided, lightning protection grounding electrode system. [NFPA 54:7.13.2.3]
Bonding connections shall be in accordance with NFPA 70. [NFPA 54:7.13.2.4]
Devices used for the bonding connection shall be listed for the application in accordance with UL 467. [NFPA 54:7.13.2.5]
Gas piping shall not be used as a grounding conductor or electrode. [NFPA 54:7.13.3]
Where a lightning protection system is installed, the bonding of the gas piping shall be in accordance with NFPA 780. [NFPA 54:7.13.4]
Electrical circuits shall not utilize gas piping or components as conductors.

Exception: Low-voltage (50V or less) control circuits, ignition circuits, and electronic flame detection device circuits shall be permitted to make use of piping or components as a part of an electric circuit. [NFPA 54:7.14]

All electrical connections between the wiring and electrically operated control devices in a piping system shall conform to the requirements of NFPA 70. [NFPA 54:7.15.1]
Any essential safety control depending on electric current as the operating medium shall be of a type that will shut off (fail safe) the flow of gas in the event of current failure. [NFPA 54:7.15.2]
Appliances and equipment shall be connected to the building piping in compliance with Section 1212.5 through Section 1212.8 by one of the following:
  1. Rigid metallic pipe and fittings.
  2. Semirigid metallic tubing and metallic fittings. Aluminum alloy tubing shall not be used in exterior locations.
  3. A listed connector in compliance with CSA Z21.24. The connector shall be used in accordance with the manufacturer's installation instructions and shall be in the same room as the appliance. Only one connector shall be used per appliance.
  4. A listed connector in compliance with CSAZ21.75. Only one connector shall be used per appliance.
  5. CSST where installed in accordance with the manufacturer's installation instructions.
  6. Listed nonmetallic gas hose connectors in accordance with Section 1212.3.
  7. Unlisted gas hose connectors for use in laboratories and educational facilities in accordance with Section 1212.4. [NFPA 54:9.6.1]
Connectors used with commercial cooking appliances that are moved for cleaning and sanitation purposes shall be installed in accordance with the connector manufacturer's installation instructions. Such connectors shall be listed in accordance with CSA Z21.69. [NFPA 54:9.6.1.3]
Movement of appliances with casters shall be limited by a restraining device installed in accordance with the connector and appliance manufacturer's installation instructions. [NFPA 54:9.6.1.4]
Suspended low-intensity infrared tube heaters shall be connected to the building piping system with a connector listed for the application in accordance with CSA Z21.24 as follows:
  1. The connector shall be installed in accordance with the tube heater installation instructions and shall be in the same room as the appliance.
  2. Only one connector shall be used per appliance. [NFPA 54:9.6.1.5]
Listed gas hose connectors shall be installed in accordance with the manufacturer's installation instructions and in accordance with Section 1212.3.1 and Section 1212.3.2. [NFPA 54:9.6.2]
Indoor gas hose connectors shall be used only to connect laboratory, shop, and ironing appliances requiring mobility during operation and installed in accordance with the following:
  1. An appliance shutoff valve shall be installed where the connector is attached to the building piping.
  2. The connector shall be of minimum length and shall not exceed 6 feet (1829 mm).
  3. The connector shall not be concealed and shall not extend from one room to another or pass through wall partitions, ceilings, or floors. [NFPA 54:9.6.2(1)]
Where outdoor gas hose connectors are used to connect portable outdoor appliances, the connector shall be listed in accordance with CSA Z21.54 and installed in accordance with the following:
  1. An appliance shutoff valve, a listed quick-disconnect device, or a listed gas convenience outlet shall be installed where the connector is attached to the supply piping and in such a manner to prevent the accumulation of water or foreign matter.
  2. This connection shall be made only in the outdoor area where the appliance is to be used. [NFPA 54:9.6.2(2)]

The connector length shall not exceed 15 feet (4572 mm).

Injection (Bunsen) burners used in laboratories and educational facilities shall be permitted to be connected to the gas supply by an unlisted hose. [NFPA 54:9.6.3]
Where portable industrial appliances, or appliances requiring mobility or subject to vibration, are connected to the building gas piping system by the use of a flexible hose, the hose shall be suitable and safe for the conditions under which it can be used. [NFPA 54:9.6.4.1]
Where industrial appliances requiring mobility are connected to the rigid piping by the use of swivel joints or couplings, the swivel joints or couplings shall be suitable for the service required, and only the minimum number required shall be installed. [NFPA 54:9.6.4.2]
Where industrial appliances subject to vibration are connected to the building piping system by the use of all metal flexible connectors, the connectors shall be suitable for the service required. [NFPA 54:9.6.4.3]
Where flexible connections are used, they shall be of the minimum practical length and shall not extend from one room to another or pass through any walls, partitions, ceilings, or floors. Flexible connections shall not be used in any concealed location. They shall be protected against physical or thermal damage and shall be provided with gas shutoff valves in readily accessible locations in rigid piping upstream from the flexible connections. [NFPA 54:9.6.4.4]
Each appliance connected to a piping system shall have an accessible, approved manual shutoff valve with a nondisplaceable valve member or a listed gas convenience outlet. Appliance shutoff valves and convenience outlets shall serve a single appliance only. The shutoff valve shall be located within 6 feet (1829 mm) of the appliance it serves. Where a connector is used, the valve shall be installed upstream of the connector. A union or flanged connection shall be provided downstream from the valve to permit removal of appliance controls. Shutoff valves serving decorative appliances shall be permitted to be installed in fireplaces if listed for such use. [NFPA 54:9.6.5, 9.6.5.1(A)(B)]

Exceptions:

  1. Shutoff valves shall be permitted to be accessibly located inside or under an appliance where such appliance is removed without removal of the shutoff valve.
  2. Shutoff valves shall be permitted to be accessibly located inside wall heaters and wall furnaces listed for recessed installation where necessary maintenance is performed without removal of the shutoff valve.
Quick-disconnect devices used to connect appliances to the building piping shall be listed to CSA Z21.41. Where installed indoors, an approved manual shutoff valve with a non-displaceable valve member shall be installed upstream of the quick-disconnect device. [NFPA 54:9.6.6.1 — 9.6.6.2]
Appliances shall be permitted to be connected to the building piping by means of a listed gas convenience outlet, in conjunction with a listed appliance connector, installed in accordance with the manufacturer's installation instructions.

Gas convenience outlets shall be listed in accordance with CSA Z21.90 and installed in accordance with the manufacturer's installation instructions. [NFPA 54:9.6.7]

Where a sediment trap is not incorporated as a part of the appliance, a sediment trap shall be installed downstream of the appliance shutoff valve as close to the inlet of the appliance as practical, before the flex connector, where used at the time of appliance installation. The sediment trap shall be either a tee fitting with a capped nipple in the bottom outlet, as illustrated in Figure 1212.9, or other device recognized as an effective sediment trap. Illuminating appliances, ranges, clothes dryers, decorative appliances for installation in vented fireplaces, gas fireplaces, and outdoor grills shall not be required to be so equipped. [NFPA 54:9.6.8]

For SI units: 1 inch = 25.4 mm

FIGURE 1212.9
METHOD OF INSTALLING A TEE FITTING SEDIMENT TRAP
[NFPA 54: FIGURE 9.6.8]

Piping shall be installed in a manner not to interfere with inspection, maintenance, or servicing of the appliance. [NFPA 54:9.6.9]
Prior to acceptance and initial operation, all piping installations shall be visually inspected and pressure tested to determine that the materials, design, fabrication, and installation practices comply with the requirements of this code. [NFPA 54:8.1.1.1]
Inspection shall consist of visual examination during or after manufacture, fabrication, assembly, or pressure tests. [NFPA 54:8.1.1.2]
Where repairs or additions are made following the pressure test, the affected piping shall be tested. Minor repairs and additions are not required to be pressure-tested provided that the work is inspected, and connections are tested with a noncorrosive leak-detecting fluid or other leak-detecting methods approved by the Authority Having Jurisdiction. [NFPA 54:8.1.1.3]
Where new branches are installed to new appliances the newly installed branch(es) shall be required to be pressure tested. Connections between the new piping and the existing piping shall be tested with a noncorrosive leak-detecting fluid or approved leak-detecting methods. [NFPA 54:8.1.1.4]
A piping system shall be tested as a complete unit or in sections. Under no circumstances shall a valve in a line be used as a bulkhead between gas in one section of the piping system and test medium in an adjacent section, unless a double block and bleed valve system is installed. A valve shall not be subjected to the test pressure unless it can be determined that the valve, including the valve closing mechanism, is designed to safely withstand the pressure. [NFPA 54:8.1.1.5]
Regulator and valve assemblies fabricated independently of the piping system in which they are to be installed shall be permitted to be tested with inert gas or air at the time of fabrication. [NFPA 54:8.1.1.6]
The test medium shall be air, nitrogen, carbon dioxide, or an inert gas. OXYGEN SHALL NEVER BE USED. [NFPA 54:8.1.2]
Test preparation shall comply with Section 1213.2.1 through Section 1213.2.6.
Pipe joints, including welds, shall be left exposed for examination during the test.

Exception: Covered or concealed pipe end joints that have been previously tested in accordance with this code. [NFPA 54:8.1.3.1]

Expansion joints shall be provided with temporary restraints, where required, for the additional thrust load under test. [NFPA 54:8.1.3.2]
Appliances and equipment that are not to be included in the test shall be either disconnected from the piping or isolated by blanks, blind flanges, or caps. Flanged joints at which blinds are inserted to blank off other equipment during the test shall not be required to be tested. [NFPA 54:8.1.3.3]
Where the piping system is connected to appliances or equipment designed for operating pressures of less than the test pressure, such appliances or equipment shall be isolated from the piping system by disconnecting them and capping the outlet(s). [NFPA 54:8.1.3.4]
Where the piping system is connected to appliances or equipment designed for operating pressures equal to or greater than the test pressure, such appliances or equipment shall be isolated from the piping system by closing the individual appliance or equipment shutoff valve(s). [NFPA 54:8.1.3.5]
All testing of piping systems shall be performed in a manner that protects the safety of employees and the public during the test. [NFPA 54:8.1.3.6]
This inspection shall include an air, CO2, or nitrogen pressure test, at which time the gas piping shall stand a pressure of not less than 10 psi (69 kPa) gauge pressure. Test pressures shall be held for a length of time satisfactory to the Authority Having Jurisdiction but in no case less than 15 minutes with no perceptible drop in pressure. For welded piping, and for piping carrying gas at pressures in excess of 14 inches water column pressure (3.5 kPa), the test pressure shall be not less than 60 psi (414 kPa) and shall be continued for a length of time satisfactory to the Authority Having Jurisdiction, but in no case for less than 30 minutes. For CSST carrying gas at pressures in excess of 14 inches water column (3.5 kPa) pressure, the test pressure shall be not less than 30 psi (207 kPa) for 30 minutes. These tests shall be made using air, CO2, or nitrogen pressure and shall be made in the presence of the Authority Having Jurisdiction. Necessary apparatus for conducting tests shall be furnished by the permit holder. Test gauges used in conducting tests shall be in accordance with Section 318.0.
The piping system shall withstand the test pressure specified without showing any evidence of leakage or other defects. Any reduction of test pressures as indicated by pressure gauges shall be deemed to indicate the presence of a leak unless such reduction can be readily attributed to some other cause. [NFPA 54:8.1.5.1]
The leakage shall be located by means of an approved gas detector, a noncorrosive leak detection fluid, or other approved leak detection methods. [NFPA 54:8.1.5.2]
Where leakage or other defects are located, the affected portion of the piping system shall be repaired or replaced and retested. [NFPA 54:8.1.5.3]
Leak checks using fuel gas shall be permitted in piping systems that have been pressure-tested in accordance with Section 1213.0. [NFPA 54:8.2.1]
During the process of turning gas on into a system of new gas piping, the entire system shall be inspected to determine that there are no open fittings or ends and that valves at unused outlets are closed and plugged or capped. [NFPA 54:8.2.2]
Immediately after the gas is turned on into a new system or into a system that has been initially restored after an interruption of service, the piping system shall be checked for leakage. Where leakage is indicated, the gas supply shall be shut off until the necessary repairs have been made. [NFPA 54:8.2.3]
Appliances and equipment shall not be placed in operation until after the piping system has been checked in accordance with Section 1213.5.2; connections to the appliance are checked for leakage and purged in accordance with Section 1213.6. [NFPA 54:8.2.4]
The purging of piping shall be in accordance with Section 1213.6.1 through Section 1213.6.3. [NFPA 54:8.3]
The purging of piping systems shall be in accordance with the provisions of Section 1213.6.1.1 through Section 1213.6.1.5 where the piping system meets either of the following:
  1. The design operating gas pressure is greater than 2 psig (14 kPa).
  2. The piping being purged contains one or more sections of pipe or tubing meeting the size and length criteria of Table 1213.6.1. [NFPA 54:8.3.1]

TABLE 1213.6.1
SIZE AND LENGTH OF PIPING [NFPA 54: TABLE 8.3.1]*

NOMINAL PIPING SIZE
(inches)
LENGTH OF PIPING
(feet)
≥ 21/2 < 3 > 50
≥ 3 < 4 > 30
≥4 < 6 > 15
≥ 6 < 8 > 10
≥ 8 Any length

For SI units: 1 inch = 25 mm, 1 foot = 304.8 mm

* CSST EHD size of 62 is equivalent to nominal 2 inches (50 mm) pipe or tubing size.

Where existing gas piping is opened, the section that is opened shall be isolated from the gas supply and the line pressure vented in accordance with Section 1213.6.1.4. Where gas piping meeting the criteria of Table 1213.6.1 is removed from service, the residual fuel gas in the piping shall be displaced with an inert gas. [NFPA 54:8.3.1.1]
Where piping containing gas is to be removed, the line shall be first disconnected from sources of gas and then thoroughly purged with air, water, or inert gas before cutting, or welding is done.
Where gas piping containing air and meeting the criteria of Table 1213.6.1 is placed in operation, the air in the piping shall first be displaced with an inert gas. The inert gas shall then be displaced with fuel gas in accordance with Section 1213.6.1.4. [NFPA 54:8.3.1.2]
The open end of a piping system being pressure vented or purged shall discharge directly to an outdoor location. Purging operations shall comply with the following requirements:
  1. The point of discharge shall be controlled with a shutoff valve.
  2. The point of discharge shall be located at least 10 feet (3048 mm) from sources of ignition, at least 10 feet (3048 mm) from building openings, and at least 25 feet (7620 mm) from mechanical air intake openings.
  3. During discharge, the open point of discharge shall be continuously attended and monitored with a combustible gas indicator that is in accordance with Section 1213.6.1.5.
  4. Purging operations introducing fuel gas shall be stopped where 90 percent fuel gas by volume is detected within the pipe.
  5. Persons not involved in the purging operations shall be evacuated from areas within 10 feet (3048 mm) of the point of discharge. [NFPA 54:8.3.1.3]
Combustible gas indicators shall be listed and calibrated in accordance with the manufacturer's instructions. Combustible gas indicators shall numerically display a volume scale from 0 percent to 100 percent in 1 percent or smaller increments. [NFPA 54:8.3.1.4]
The purging of piping systems shall be in accordance with the provisions of Section 1213.6.2.1 where the piping system meets both of the following:
  1. The design operating pressure is 2 psig (14 kPa) or less.
  2. The piping being purged is constructed entirely from pipe or tubing not meeting the size and length criteria of Table 1213.6.1. [NFPA 54:8.3.2]
The piping system shall be purged in accordance with one or more of the following:
  1. The piping shall be purged with fuel gas and shall discharge to the outdoors.
  2. The piping shall be purged with fuel gas and shall discharge to the indoors or outdoors through an appliance burner not located in a combustion chamber. Such burner shall be provided with a continuous source of ignition.
  3. The piping shall be purged with fuel gas and shall discharge to the indoors or outdoors through a burner that has a continuous source of ignition, and that is designed for such purpose.
  4. The piping shall be purged with fuel gas that is discharged to the indoors or outdoors, and the point of discharge shall be monitored with a listed combustible gas detector in accordance with Section 1213.6.2.2. Purging shall be stopped where fuel gas is detected.
  5. The piping shall be purged by the gas supplier in accordance with written procedures. [NFPA 54:8.3.2.1]
Combustible gas detectors shall be listed and calibrated or tested in accordance with the manufacturer's instructions. Combustible gas detectors shall be capable of indicating the presence of fuel gas. [NFPA 54:8.3.2.2]
After the piping system has been placed in operation, appliances and equipment shall be purged before being placed into operation. [NFPA 54:8.3.3]
The following regulations shall comply with this section and Section 1215.0, shall be the standard for the installation of gas piping. Natural gas regulations and tables are based on the use of a gas having a specific gravity of 0.60 and for undiluted liquefied petroleum gas, having a specific gravity of 1.50. Where gas of a different specific gravity is to be delivered, the specific gravity conversion factors provided by the serving gas supplier shall be used in sizing piping systems from the pipe sizing tables in this chapter.
The hourly volume of gas required at each piping outlet shall be taken as not less than the maximum hourly rating as specified by the manufacturer of the appliance or appliances to be connected to each such outlet.
Where the gas appliances to be installed have not been specified, Table 1208.4.1 shall be permitted to be used as a reference to estimate requirements of typical appliances.

To obtain the cubic feet per hour (m3/h) of gas required, divide the input of the appliances by the average Btu (kW•h) heating value per cubic foot (m3) of the gas. The average Btu (kW•h) per cubic foot (m3) of the gas in the area of the installation shall be permitted to be obtained from the serving gas supplier.

The size of the supply piping outlet for a gas appliance shall be not less than 1/2 of an inch in diameter (15 mm).

The size of a piping outlet for a mobile home shall be not less than 3/4 of an inch in diameter (20 mm).

Where the pipe size is to be determined using any of the methods in Section 1215.1.1 through Section 1215.1.3, the diameter of each pipe segment shall be obtained from the pipe sizing tables in Section 1215.2 or the sizing equations in Section 1215.3. [NFPA 54:6.1]
The pipe size of each section of gas piping shall be determined using the longest length of piping from the point of delivery to the most remote outlet and the load of the section (see calculation example in Figure 1215.1.1). [NFPA 54:6.1.1]

FIGURE 1215.1.1
EXAMPLE ILLUSTRATING USE OF TABLE 1208.4.1 AND TABLE 1215.2(1)

Problem: Determine the required pipe size of each section and outlet of the piping system shown in Figure 1215.1.1. Gas to be used has a specific gravity of 0.60 and 1100 British thermal units (Btu) per cubic foot (0.0114 kW•h/L), delivered at 8 inch water column (1.9 kPa) pressure.

For SI units: 1 foot = 304.8 mm, 1 gallon = 3.785 L, 1000 British thermal units per hour = 0.293 kW, 1 cubic foot per hour = 0.0283 m3/h

Solution:

  1. Maximum gas demand of Outlet A —

    32 cubic feet per hour (0.91 m3/h) (from Table 1208.4.1).

    Maximum gas demand of Outlet B —

    3 cubic feet per hour (0.08 m3/h) (from Table 1208.4.1).

    Maximum gas demand of Outlet C —

    59 cubic feet per hour (1.67 m3/h) (from Table 1208.4.1).

    Maximum gas demand of Outlet D —

    136 cubic feet per hour (3.85 m3/h) [150 000 Btu/hour (44 kW) divided by 1100 Btu per cubic foot (0.0114 kW•h/L)].

  2. The length of pipe from the gas meter to the most remote outlet (Outlet A) is 60 feet (18 288 mm).
  3. Using the length in feet column row marked 60 feet (18 288 mm) in Table 1215.2(1):

    Outlet A, supplying 32 cubic feet per hour (0.91 m3/h), requires 1/2 of an inch (15 mm) pipe.

    Section 1, supplying Outlets A and B, or 35 cubic feet per hour (0.99 m3/h) requires 1/2 of an inch (15 mm) pipe.

    Section 2, supplying Outlets A, B, and C, or 94 cubic feet per hour (2.66 m3/h) requires 3/4 of an inch (20 mm) pipe.

    Section 3, supplying Outlets A, B, C, and D, or 230 cubic feet per hour (6.51 m3/h), requires 1 inch (25 mm) pipe.

  4. Using the column marked 60 feet (18 288 mm) in Table 1215.2(1) [no column for actual length of 55 feet (16 764 mm)]:

    Outlet B supplying 3 cubic feet per hour (0.08 m3/h), requires 1/2 of an inch (15 mm) pipe.

    Outlet C, supplying 59 cubic feet per hour (1.67 m3/h), requires 1/2 of an inch (15 mm) pipe.

  5. Using the column marked 60 feet (18 288 mm) in Table 1215.2(1):

    Outlet D, supplying 136 cubic feet per hour (3.85 m3/h), requires 3/4 of an inch (20 mm) pipe.

Pipe shall be sized as follows:
  1. The pipe size of each section of the longest pipe run from the point of delivery to the most remote outlet shall be determined using the longest run of piping and the load of the section.
  2. The pipe size of each section of branch piping not previously sized shall be determined using the length of piping from the point of delivery to the most remote outlet in each branch and the load of the section. [NFPA 54:6.1.2]
The pipe size for each section of higher pressure gas piping shall be determined using the longest length of piping from the point of delivery to the most remote line pressure regulator. The pipe size from the line pressure regulator to each outlet shall be determined using the length of piping from the regulator to the most remote outlet served by the regulator. [NFPA 54:6.1.3]
Table 1215.2(1) through Table 1215.2(36) shall be used to size gas piping in conjunction with one of the methods described in Section 1215.1.1 through Section 1215.1.3. [NFPA 54:6.2]

TABLE 1215.2(1)
SCHEDULE 40 METALLIC PIPE [NFPA 54:TABLE 6.2(b)]1, 2

GAS: NATURAL
INLET PRESSURE: LESS THAN 2 psi
PRESSURE DROP: 0.5 in. w.c.
SPECIFIC GRAVITY: 0.60
PIPE SIZE (inch)
NOMINAL: 1/2 3/4 1 11/4 11/2 2 21/2 3 4 5 6 8 10 12
ACTUAL ID: 0.622 0.824 1.049 1.380 1.610 2.067 2.469 3.068 4.026 5.047 6.065 7.981 10.020 11.938
LENGTH
(feet)
CAPACITY IN CUBIC FEET OF GAS PER HOUR
10 172 360 678 1390 2090 4020 6400 11 300 23 100 41 800 67 600 139 000 252 000 399 000
20 118 247 466 957 1430 2760 4400 7780 15 900 28 700 46 500 95 500 173 000 275 000
30 95 199 374 768 1150 2220 3530 6250 12 700 23 000 37 300 76 700 139 000 220 000
40 81 170 320 657 985 1900 3020 5350 10 900 19 700 31 900 65 600 119 000 189 000
50 72 151 284 583 873 1680 2680 4740 9660 17 500 28 300 58 200 106 000 167 000
60 65 137 257 528 791 1520 2430 4290 8760 15 800 25 600 52 700 95 700 152 000
70 60 126 237 486 728 1400 2230 3950 8050 14 600 23 600 48 500 88 100 139 000
80 56 117 220 452 677 1300 2080 3670 7490 13 600 22 000 45 100 81 900 130 000
90 52 110 207 424 635 1220 1950 3450 7030 12 700 20 600 42 300 76 900 122 000
100 50 104 195 400 600 1160 1840 3260 6640 12 000 19 500 40 000 72 600 115 000
125 44 92 173 355 532 1020 1630 2890 5890 10 600 17 200 35 400 64 300 102 000
150 40 83 157 322 482 928 1480 2610 5330 9650 15 600 32 100 58 300 92 300
175 37 77 144 296 443 854 1360 2410 4910 8880 14 400 29 500 53 600 84 900
200 34 71 134 275 412 794 1270 2240 4560 8260 13 400 27 500 49 900 79 000
250 30 63 119 244 366 704 1120 1980 4050 7320 11 900 24 300 44 200 70 000
300 27 57 108 221 331 638 1020 1800 3670 6630 10 700 22 100 40 100 63 400
350 25 53 99 203 305 587 935 1650 3370 6100 9880 20 300 36 900 58 400
400 23 49 92 189 283 546 870 1540 3140 5680 9190 18 900 34 300 54 300
450 22 46 86 177 266 512 816 1440 2940 5330 8620 17 700 32 200 50 900
500 21 43 82 168 251 484 771 1360 2780 5030 8150 16 700 30 400 48 100
550 20 41 78 159 239 459 732 1290 2640 4780 7740 15 900 28 900 45 700
600 19 39 74 152 228 438 699 1240 2520 4560 7380 15 200 27 500 43 600
650 18 38 71 145 218 420 669 1180 2410 4360 7070 14 500 26 400 41 800
700 17 36 68 140 209 403 643 1140 2320 4190 6790 14 000 25 300 40 100
750 17 35 66 135 202 389 619 1090 2230 4040 6540 13 400 24 400 38 600
800 16 34 63 130 195 375 598 1060 2160 3900 6320 13 000 23 600 37 300
850 16 33 61 126 189 363 579 1020 2090 3780 6110 12 600 22 800 36 100
900 15 32 59 122 183 352 561 992 2020 3660 5930 12 200 22 100 35 000
950 15 31 58 118 178 342 545 963 1960 3550 5760 11 800 21 500 34 000
1000 14 30 56 115 173 333 530 937 1910 3460 5600 11 500 20 900 33 100
1100 14 28 53 109 164 316 503 890 1810 3280 5320 10 900 19 800 31 400
1200 13 27 51 104 156 301 480 849 1730 3130 5070 10 400 18 900 30 000
1300 12 26 49 100 150 289 460 813 1660 3000 4860 9980 18 100 28 700
1400 12 25 47 96 144 277 442 781 1590 2880 4670 9590 17 400 27 600
1500 11 24 45 93 139 267 426 752 1530 2780 4500 9240 16 800 26 600
1600 11 23 44 89 134 258 411 727 1480 2680 4340 8920 16 200 25 600
1700 11 22 42 86 130 250 398 703 1430 2590 4200 8630 15 700 24 800
1800 10 22 41 84 126 242 386 682 1390 2520 4070 8370 15 200 24 100
1900 10 21 40 81 122 235 375 662 1350 2440 3960 8130 14 800 23 400
2000 NA 20 39 79 119 229 364 644 1310 2380 3850 7910 14 400 22 700

For SI units: 1 inch = 25 mm, 1 foot = 304.8 mm, 1 cubic foot per hour = 0.0283 m3/h, 1 pound-force per square inch = 6.8947 kPa, 1 inch water column = 0.249 kPa

Notes:

1 Table entries are rounded to 3 significant digits.

2 NA means a flow of less than 10 ft3/h (0.283 m3/h).

TABLE 1215.2(2)
SCHEDULE 40 METALLIC PIPE [NFPA 54: TABLE 6.2(c)]*

GAS: NATURAL
INLET PRESSURE: LESS THAN 2 psi
PRESSURE DROP: 3.0 in. w.c.
SPECIFIC GRAVITY: 0.60
INTENDED USE: INITIAL SUPPLY PRESSURE OF 8.0 IN. W.C. OR GREATER
PIPE SIZE (inch)
NOMINAL: 1/2 3/4 1 11/4 11/2 2 21/2 3 4
ACTUAL ID: 0.622 0.824 1.049 1.380 1.610 2.067 2.469 3.068 4.026
LENGTH
(feet)
CAPACITY IN CUBIC FEET OF GAS PER HOUR
10 454 949 1790 3670 5500 10 600 16 900 29 800 60 800
20 312 652 1230 2520 3780 7280 11 600 20 500 41 800
30 250 524 986 2030 3030 5840 9310 16 500 33 600
40 214 448 844 1730 2600 5000 7970 14 100 28 700
50 190 397 748 1540 2300 4430 7060 12 500 25 500
60 172 360 678 1390 2090 4020 6400 11 300 23 100
70 158 331 624 1280 1920 3690 5890 10 400 21 200
80 147 308 580 1190 1790 3440 5480 9690 19 800
90 138 289 544 1120 1670 3230 5140 9090 18 500
100 131 273 514 1060 1580 3050 4860 8580 17 500
125 116 242 456 936 1400 2700 4300 7610 15 500
150 105 219 413 848 1270 2450 3900 6890 14 100
175 96 202 380 780 1170 2250 3590 6340 12 900
200 90 188 353 726 1090 2090 3340 5900 12 000
250 80 166 313 643 964 1860 2960 5230 10 700
300 72 151 284 583 873 1680 2680 4740 9660
350 66 139 261 536 803 1550 2470 4360 8890
400 62 129 243 499 747 1440 2290 4050 8270
450 58 121 228 468 701 1350 2150 3800 7760
500 55 114 215 442 662 1280 2030 3590 7330
550 52 109 204 420 629 1210 1930 3410 6960
600 50 104 195 400 600 1160 1840 3260 6640
650 47 99 187 384 575 1110 1760 3120 6360
700 46 95 179 368 552 1060 1690 3000 6110
750 44 92 173 355 532 1020 1630 2890 5890
800 42 89 167 343 514 989 1580 2790 5680
850 41 86 162 332 497 957 1530 2700 5500
900 40 83 157 322 482 928 1480 2610 5330
950 39 81 152 312 468 901 1440 2540 5180
1000 38 79 148 304 455 877 1400 2470 5040
1100 36 75 141 289 432 833 1330 2350 4780
1200 34 71 134 275 412 794 1270 2240 4560
1300 33 68 128 264 395 761 1210 2140 4370
1400 31 65 123 253 379 731 1160 2060 4200
1500 30 63 119 244 366 704 1120 1980 4050
1600 29 61 115 236 353 680 1080 1920 3910
1700 28 59 111 228 342 658 1050 1850 3780
1800 27 57 108 221 331 638 1020 1800 3670
1900 27 56 105 215 322 619 987 1750 3560
2000 26 54 102 209 313 602 960 1700 3460

For SI units: 1 inch = 25 mm, 1 foot = 304.8 mm, 1 cubic foot per hour = 0.0283 m3/h, 1 pound-force per square inch = 6.8947 kPa, 1 inch water column = 0.249 kPa

* Table entries are rounded to 3 significant digits.

TABLE 1215.2(3)
SCHEDULE 40 METALLIC PIPE [NFPA 54: TABLE 6.2(d)]*

GAS: NATURAL
INLET PRESSURE: LESS THAN 2 psi
PRESSURE DROP: 6.0 in. w.c.
SPECIFIC GRAVITY: 0.60
INTENDED USE: INITIAL SUPPLY PRESSURE OF 11.0 IN. W.C. OR GREATER
PIPE SIZE (inch)
NOMINAL: 1/2 3/4 1 11/4 11/2 2 21/2 3 4
ACTUAL ID: 0.622 0.824 1.049 1.38 1.61 2.067 2.469 3.068 4.026
LENGTH
(feet)
CAPACITY IN CUBIC FEET OF GAS PER HOUR
10 660 1380 2600 5340 8000 15 400 24 600 43 400 88 500
20 454 949 1790 3670 5500 10 600 16 900 29 800 60 800
30 364 762 1440 2950 4410 8500 13 600 24 000 48 900
40 312 652 1230 2520 3780 7280 11 600 20 500 41 800
50 276 578 1090 2240 3350 6450 10 300 18 200 37 100
60 250 524 986 2030 3030 5840 9310 16 500 33 600
70 230 482 907 1860 2790 5380 8570 15 100 30 900
80 214 448 844 1730 2600 5000 7970 14 100 28 700
90 201 420 792 1630 2440 4690 7480 13 200 27 000
100 190 397 748 1540 2300 4430 7060 12 500 25 500
125 168 352 663 1360 2040 3930 6260 11 100 22 600
150 153 319 601 1230 1850 3560 5670 10 000 20 500
175 140 293 553 1140 1700 3270 5220 9230 18 800
200 131 273 514 1056 1580 3050 4860 8580 17 500
250 116 242 456 936 1400 2700 4300 7610 15 500
300 105 219 413 848 1270 2450 3900 6890 14 100
350 96 202 380 780 1170 2250 3590 6340 12 900
400 90 188 353 726 1090 2090 3340 5900 12 000
450 84 176 332 681 1020 1960 3130 5540 11 300
500 80 166 313 643 964 1860 2960 5230 10 700
550 76 158 297 611 915 1760 2810 4970 10 100
600 72 151 284 583 873 1680 2680 4740 9660
650 69 144 272 558 836 1610 2570 4540 9250
700 66 139 261 536 803 1550 2470 4360 8890
750 64 134 252 516 774 1490 2380 4200 8560
800 62 129 243 499 747 1440 2290 4050 8270
850 60 125 235 483 723 1390 2220 3920 8000
900 58 121 228 468 701 1350 2150 3800 7760
950 56 118 221 454 681 1310 2090 3690 7540
1000 55 114 215 442 662 1280 2030 3590 7330
1100 52 109 204 420 629 1210 1930 3410 6960
1200 50 104 195 400 600 1160 1840 3260 6640
1300 47 99 187 384 575 1110 1760 3120 6360
1400 46 95 179 368 552 1060 1690 3000 6110
1500 44 92 173 355 532 1020 1630 2890 5890
1600 42 89 167 343 514 989 1580 2790 5680
1700 41 86 162 332 497 957 1530 2700 5500
1800 40 83 157 322 482 928 1480 2610 5330
1900 39 81 152 312 468 901 1440 2540 5180
2000 38 79 148 304 455 877 1400 2470 5040

For SI units: 1 inch = 25 mm, 1 foot = 304.8 mm, 1 cubic foot per hour = 0.0283 m3/h, 1 pound-force per square inch = 6.8947 kPa, 1 inch water column = 0.249 kPa

* Table entries are rounded to 3 significant digits.

TABLE 1215.2(4)
SCHEDULE 40 METALLIC PIPE [NFPA 54: TABLE 6.2(e)]*

GAS: NATURAL
INLET PRESSURE: 2.0 psi
PRESSURE DROP: 1.0 psi
SPECIFIC GRAVITY: 0.60
PIPE SIZE (inch)
NOMINAL: 1/2 3/4 1 11/4 11/2 2 21/2 3 4
ACTUAL ID: 0.622 0.824 1.049 1.380 1.610 2.067 2.469 3.068 4.026
LENGTH
(feet)
CAPACITY IN CUBIC FEET OF GAS PER HOUR
10 1510 3040 5560 11 400 17 100 32 900 52 500 92 800 189 000
20 1070 2150 3930 8070 12 100 23 300 37 100 65 600 134 000
30 869 1760 3210 6590 9880 19 000 30 300 53 600 109 000
40 753 1520 2780 5710 8550 16 500 26 300 46 400 94 700
50 673 1360 2490 5110 7650 14 700 23 500 41 500 84 700
60 615 1240 2270 4660 6980 13 500 21 400 37 900 77 300
70 569 1150 2100 4320 6470 12 500 19 900 35 100 71 600
80 532 1080 1970 4040 6050 11 700 18 600 32 800 67 000
90 502 1010 1850 3810 5700 11 000 17 500 30 900 63 100
100 462 934 1710 3510 5260 10 100 16 100 28 500 58 200
125 414 836 1530 3140 4700 9060 14 400 25 500 52 100
150 372 751 1370 2820 4220 8130 13 000 22 900 46 700
175 344 695 1270 2601 3910 7530 12 000 21 200 43 300
200 318 642 1170 2410 3610 6960 11 100 19 600 40 000
250 279 583 1040 2140 3210 6180 9850 17 400 35 500
300 253 528 945 1940 2910 5600 8920 15 800 32 200
350 232 486 869 1790 2670 5150 8210 14 500 29 600
400 216 452 809 1660 2490 4790 7640 13 500 27 500
450 203 424 759 1560 2330 4500 7170 12 700 25 800
500 192 401 717 1470 2210 4250 6770 12 000 24 400
550 182 381 681 1400 2090 4030 6430 11 400 23 200
600 174 363 650 1330 2000 3850 6130 10 800 22 100
650 166 348 622 1280 1910 3680 5870 10 400 21 200
700 160 334 598 1230 1840 3540 5640 9970 20 300
750 154 322 576 1180 1770 3410 5440 9610 19 600
800 149 311 556 1140 1710 3290 5250 9280 18 900
850 144 301 538 1100 1650 3190 5080 8980 18 300
900 139 292 522 1070 1600 3090 4930 8710 17 800
950 135 283 507 1040 1560 3000 4780 8460 17 200
1000 132 275 493 1010 1520 2920 4650 8220 16 800
1100 125 262 468 960 1440 2770 4420 7810 15 900
1200 119 250 446 917 1370 2640 4220 7450 15 200
1300 114 239 427 878 1320 2530 4040 7140 14 600
1400 110 230 411 843 1260 2430 3880 6860 14 000
1500 106 221 396 812 1220 2340 3740 6600 13 500
1600 102 214 382 784 1180 2260 3610 6380 13 000
1700 99 207 370 759 1140 2190 3490 6170 12 600
1800 96 200 358 736 1100 2120 3390 5980 12 200
1900 93 195 348 715 1070 2060 3290 5810 11 900
2000 91 189 339 695 1040 2010 3200 5650 11 500

For SI units: 1 inch = 25 mm, 1 foot = 304.8 mm, 1 cubic foot per hour = 0.0283 m3/h, 1 pound-force per square inch = 6.8947 kPa

* Table entries are rounded to 3 significant digits.

TABLE 1215.2(5)
SCHEDULE 40 METALLIC PIPE [NFPA 54: TABLE 6.2(f)]*

GAS: NATURAL
INLET PRESSURE: 3.0 psi
PRESSURE DROP: 2.0 psi
SPECIFIC GRAVITY: 0.60
PIPE SIZE (inch)
NOMINAL: 1/2 3/4 1 11/4 11/2 2 21/2 3 4
ACTUAL ID: 0.622 0.824 1.049 1.380 1.610 2.067 2.469 3.068 4.026
LENGTH
(feet)
CAPACITY IN CUBIC FEET OF GAS PER HOUR
10 2350 4920 9270 19 000 28 500 54 900 87 500 155 000 316 000
20 1620 3380 6370 13 100 19 600 37 700 60 100 106 000 217 000
30 1300 2720 5110 10 500 15 700 30 300 48 300 85 400 174 000
40 1110 2320 4380 8990 13 500 25 900 41 300 73 100 149 000
50 985 2060 3880 7970 11 900 23 000 36 600 64 800 132 000
60 892 1870 3520 7220 10 800 20 800 33 200 58 700 120 000
70 821 1720 3230 6640 9950 19 200 30 500 54 000 110 000
80 764 1600 3010 6180 9260 17 800 28 400 50 200 102 000
90 717 1500 2820 5800 8680 16 700 26 700 47 100 96 100
100 677 1420 2670 5470 8200 15 800 25 200 44 500 90 800
125 600 1250 2360 4850 7270 14 000 22 300 39 500 80 500
150 544 1140 2140 4400 6590 12 700 20 200 35 700 72 900
175 500 1050 1970 4040 6060 11 700 18 600 32 900 67 100
200 465 973 1830 3760 5640 10 900 17 300 30 600 62 400
250 412 862 1620 3330 5000 9620 15 300 27 100 55 300
300 374 781 1470 3020 4530 8720 13 900 24 600 50 100
350 344 719 1350 2780 4170 8020 12 800 22 600 46 100
400 320 669 1260 2590 3870 7460 11 900 21 000 42 900
450 300 627 1180 2430 3640 7000 11 200 19 700 40 200
500 283 593 1120 2290 3430 6610 10 500 18 600 38 000
550 269 563 1060 2180 3260 6280 10 000 17 700 36 100
600 257 537 1010 2080 3110 5990 9550 16 900 34 400
650 246 514 969 1990 2980 5740 9150 16 200 33 000
700 236 494 931 1910 2860 5510 8790 15 500 31 700
750 228 476 897 1840 2760 5310 8470 15 000 30 500
800 220 460 866 1780 2660 5130 8180 14 500 29 500
850 213 445 838 1720 2580 4960 7910 14 000 28 500
900 206 431 812 1670 2500 4810 7670 13 600 27 700
950 200 419 789 1620 2430 4670 7450 13 200 26 900
1000 195 407 767 1580 2360 4550 7240 12 800 26 100
1100 185 387 729 1500 2240 4320 6890 12 200 24 800
1200 177 369 695 1430 2140 4120 6570 11 600 23 700
1300 169 353 666 1370 2050 3940 6290 11 100 22 700
1400 162 340 640 1310 1970 3790 6040 10 700 21 800
1500 156 327 616 1270 1900 3650 5820 10 300 21 000
1600 151 316 595 1220 1830 3530 5620 10 000 20 300
1700 146 306 576 1180 1770 3410 5440 9610 19 600
1800 142 296 558 1150 1720 3310 5270 9320 19 000
1900 138 288 542 1110 1670 3210 5120 9050 18 400
2000 134 280 527 1080 1620 3120 4980 8800 18 000

For SI units: 1 inch = 25 mm, 1 foot = 304.8 mm, 1 cubic foot per hour = 0.0283 m3/h, 1 pound-force per square inch = 6.8947 kPa

* Table entries are rounded to 3 significant digits.

TABLE 1215.2(6)
SCHEDULE 40 METALLIC PIPE [NFPA 54: TABLE 6.2(g)]*

GAS: NATURAL
INLET PRESSURE: 5.0 psi
PRESSURE DROP: 3.5 psi
SPECIFIC GRAVITY: 0.60
PIPE SIZE (inch)
NOMINAL: 1/2 3/4 1 11/4 11/2 2 21/2 3 4
ACTUAL ID: 0.622 0.824 1.049 1.380 1.610 2.067 2.469 3.068 4.026
LENGTH
(feet)
CAPACITY IN CUBIC FEET OF GAS PER HOUR
10 3190 6430 11 800 24 200 36 200 69 700 111 000 196 000 401 000
20 2250 4550 8320 17 100 25 600 49 300 78 600 139 000 283 000
30 1840 3720 6790 14 000 20 900 40 300 64 200 113 000 231 000
40 1590 3220 5880 12 100 18 100 34 900 55 600 98 200 200 000
50 1430 2880 5260 10 800 16 200 31 200 49 700 87 900 179 000
60 1300 2630 4800 9860 14 800 28 500 45 400 80 200 164 000
70 1200 2430 4450 9130 13 700 26 400 42 000 74 300 151 000
80 1150 2330 4260 8540 12 800 24 700 39 300 69 500 142 000
90 1060 2150 3920 8050 12 100 23 200 37 000 65 500 134 000
100 979 1980 3620 7430 11 100 21 400 34 200 60 400 123 000
125 876 1770 3240 6640 9950 19 200 30 600 54 000 110 000
150 786 1590 2910 5960 8940 17 200 27 400 48 500 98 900
175 728 1470 2690 5520 8270 15 900 25 400 44 900 91 600
200 673 1360 2490 5100 7650 14 700 23 500 41 500 84 700
250 558 1170 2200 4510 6760 13 000 20 800 36 700 74 900
300 506 1060 1990 4090 6130 11 800 18 800 33 300 67 800
350 465 973 1830 3760 5640 10 900 17 300 30 600 62 400
400 433 905 1710 3500 5250 10 100 16 100 28 500 58 100
450 406 849 1600 3290 4920 9480 15 100 26 700 54 500
500 384 802 1510 3100 4650 8950 14 300 25 200 51 500
550 364 762 1440 2950 4420 8500 13 600 24 000 48 900
600 348 727 1370 2810 4210 8110 12 900 22 900 46 600
650 333 696 1310 2690 4030 7770 12 400 21 900 44 600
700 320 669 1260 2590 3880 7460 11 900 21 000 42 900
750 308 644 1210 2490 3730 7190 11 500 20 300 41 300
800 298 622 1170 2410 3610 6940 11 100 19 600 39 900
850 288 602 1130 2330 3490 6720 10 700 18 900 38 600
900 279 584 1100 2260 3380 6520 10 400 18 400 37 400
950 271 567 1070 2190 3290 6330 10 100 17 800 36 400
1000 264 551 1040 2130 3200 6150 9810 17 300 35 400
1100 250 524 987 2030 3030 5840 9320 16 500 33 600
1200 239 500 941 1930 2900 5580 8890 15 700 32 000
1300 229 478 901 1850 2770 5340 8510 15 000 30 700
1400 220 460 866 1780 2660 5130 8180 14 500 29 500
1500 212 443 834 1710 2570 4940 7880 13 900 28 400
1600 205 428 806 1650 2480 4770 7610 13 400 27 400
1700 198 414 780 1600 2400 4620 7360 13 000 26 500
1800 192 401 756 1550 2330 4480 7140 12 600 25 700
1900 186 390 734 1510 2260 4350 6930 12 300 25 000
2000 181 379 714 1470 2200 4230 6740 11 900 24 300

For SI units: 1 inch = 25 mm, 1 foot = 304.8 mm, 1 cubic foot per hour = 0.0283 m3/h, 1 pound-force per square inch = 6.8947 kPa

* Table entries are rounded to 3 significant digits.

TABLE 1215.2(7)
SEMI-RIGID COPPER TUBING [NFPA 54: TABLE 6.2(h)]1, 2

GAS: NATURAL
INLET PRESSURE: LESS THAN 2 psi
PRESSURE DROP: 0.3 in. w.c.
SPECIFIC GRAVITY: 0.60
TUBE SIZE (inch)
NOMINAL: K & L: 1/4 3/8 1/2 5/8 3/4 1 11/4 11/2 2
ACR: 3/8 1/2 5/8 3/4 7/8 11/8 13/8
OUTSIDE: 0.375 0.500 0.625 0.750 0.875 1.125 1.375 1.625 2.125
INSIDE:3 0.305 0.402 0.527 0.652 0.745 0.995 1.245 1.481 1.959
LENGTH
(feet)
CAPACITY IN CUBIC FEET OF GAS PER HOUR
10 20 42 85 148 210 448 806 1270 2650
20 14 29 58 102 144 308 554 873 1820
30 11 23 47 82 116 247 445 701 1460
40 10 20 40 70 99 211 381 600 1250
50 NA 17 35 62 88 187 337 532 1110
60 NA 16 32 56 79 170 306 482 1000
70 NA 14 29 52 73 156 281 443 924
80 NA 13 27 48 68 145 262 413 859
90 NA 13 26 45 64 136 245 387 806
100 NA 12 24 43 60 129 232 366 761
125 NA 11 22 38 53 114 206 324 675
150 NA 10 20 34 48 103 186 294 612
175 NA NA 18 31 45 95 171 270 563
200 NA NA 17 29 41 89 159 251 523
250 NA NA 15 26 37 78 141 223 464
300 NA NA 13 23 33 71 128 202 420
350 NA NA 12 22 31 65 118 186 387
400 NA NA 11 20 28 61 110 173 360
450 NA NA 11 19 27 57 103 162 338
500 NA NA 10 18 25 54 97 153 319
550 NA NA NA 17 24 51 92 145 303
600 NA NA NA 16 23 49 88 139 289
650 NA NA NA 15 22 47 84 133 277
700 NA NA NA 15 21 45 81 128 266
750 NA NA NA 14 20 43 78 123 256
800 NA NA NA 14 20 42 75 119 247
850 NA NA NA 13 19 40 73 115 239
900 NA NA NA 13 18 39 71 111 232
950 NA NA NA 13 18 38 69 108 225
1000 NA NA NA 12 17 37 67 105 219
1100 NA NA NA 12 16 35 63 100 208
1200 NA NA NA 11 16 34 60 95 199
1300 NA NA NA 11 15 32 58 91 190
1400 NA NA NA 10 14 31 56 88 183
1500 NA NA NA NA 14 30 54 84 176
1600 NA NA NA NA 13 29 52 82 170
1700 NA NA NA NA 13 28 50 79 164
1800 NA NA NA NA 13 27 49 77 159
1900 NA NA NA NA 12 26 47 74 155
2000 NA NA NA NA 12 25 46 72 151

For SI units: 1 inch = 25 mm, 1 foot = 304.8 mm, 1 cubic foot per hour = 0.0283 m3/h, 1 pound-force per square inch = 6.8947 kPa, 1 inch water column = 0.249 kPa

Notes:

1 Table entries are rounded to 3 significant digits.

2 NA means a flow of less than 10 ft3/h (0.283 m3/h).

3 Table capacities are based on Type K copper tubing inside diameter (shown), which has the smallest inside diameter of the copper tubing products.

TABLE 1215.2(8)
SEMI-RIGID COPPER TUBING [NFPA 54: TABLE 6.2(i)]1, 2

GAS: NATURAL
INLET PRESSURE: LESS THAN 2 psi
PRESSURE DROP: 0.5 in. w.c.
SPECIFIC GRAVITY: 0.60
TUBE SIZE (inch)
NOMINAL: K & L: 1/4 3/8 1/2 5/8 3/4 1 11/4 11/2 2
ACR: 3/8 1/2 5/8 3/4 7/8 11/8 13/8
OUTSIDE: 0.375 0.500 0.625 0.750 0.875 1.125 1.375 1.625 2.125
INSIDE:3 0.305 0.402 0.527 0.652 0.745 0.995 1.245 1.481 1.959
LENGTH (feet) CAPACITY IN CUBIC FEET OF GAS PER HOUR
10 27 55 111 195 276 590 1060 1680 3490
20 18 38 77 134 190 406 730 1150 2400
30 15 30 61 107 152 326 586 925 1930
40 13 26 53 92 131 279 502 791 1650
50 11 23 47 82 116 247 445 701 1460
60 10 21 42 74 105 224 403 635 1320
70 NA 19 39 68 96 206 371 585 1220
80 NA 18 36 63 90 192 345 544 1130
90 NA 17 34 59 84 180 324 510 1060
100 NA 16 32 56 79 170 306 482 1000
125 NA 14 28 50 70 151 271 427 890
150 NA 13 26 45 64 136 245 387 806
175 NA 12 24 41 59 125 226 356 742
200 NA 11 22 39 55 117 210 331 690
250 NA NA 20 34 48 103 186 294 612
300 NA NA 18 31 44 94 169 266 554
350 NA NA 16 28 40 86 155 245 510
400 NA NA 15 26 38 80 144 228 474
450 NA NA 14 25 35 75 135 214 445
500 NA NA 13 23 33 71 128 202 420
550 NA NA 13 22 32 68 122 192 399
600 NA NA 12 21 30 64 116 183 381
650 NA NA 12 20 29 62 111 175 365
700 NA NA 11 20 28 59 107 168 350
750 NA NA 11 19 27 57 103 162 338
800 NA NA 10 18 26 55 99 156 326
850 NA NA 10 18 25 53 96 151 315
900 NA NA NA 17 24 52 93 147 306
950 NA NA NA 17 24 50 90 143 297
1000 NA NA NA 16 23 49 88 139 289
1100 NA NA NA 15 22 46 84 132 274
1200 NA NA NA 15 21 44 80 126 262
1300 NA NA NA 14 20 42 76 120 251
1400 NA NA NA 13 19 41 73 116 241
1500 NA NA NA 13 18 39 71 111 232
1600 NA NA NA 13 18 38 68 108 224
1700 NA NA NA 12 17 37 66 104 217
1800 NA NA NA 12 17 36 64 101 210
1900 NA NA NA 11 16 35 62 98 204
2000 NA NA NA 11 16 34 60 95 199

For SI units: 1 inch = 25 mm, 1 foot = 304.8 mm, 1 cubic foot per hour = 0.0283 m3/h, 1 pound-force per square inch = 6.8947 kPa, 1 inch water column = 0.249 kPa

Notes:

1 Table entries are rounded to 3 significant digits.

2 NA means a flow of less than 10 ft3/h (0.283 m3/h).

3 Table capacities are based on Type K copper tubing inside diameter (shown), which has the smallest inside diameter of the copper tubing products.

TABLE 1215.2(9)
SEMI-RIGID COPPER TUBING [NFPA 54: TABLE 6.2(j)]1, 2

GAS: NATURAL
INLET PRESSURE: LESS THAN 2 psi
PRESSURE DROP: 1.0 in. w.c.
SPECIFIC GRAVITY: 0.60
INTENDED USE: TUBE SIZING BETWEEN HOUSE LINE REGULATOR AND THE APPLIANCE
TUBE SIZE (inch)
NOMINAL: K & L: 1/4 3/8 1/2 5/8 3/4 1 11/4 11/2 2
ACR: 3/8 1/2 5/8 3/4 7/8 11/8 13/8
OUTSIDE: 0.375 0.500 0.625 0.750 0.875 1.125 1.375 1.625 2.125
INSIDE:3 0.305 0.402 0.527 0.652 0.745