Materials used for piping systems shall comply with the requirements of this chapter or shall be approved.
Material not covered by the standards specifications listed herein shall be investigated and tested to determine that it is safe and suitable for the proposed service, and, in addition, shall be recommended for that service by the manufacturer and shall be approved by the code official.
Cast-iron pipe shall not be used.
Steel and wrought-iron pipe shall be not less than standard weight (Schedule 40) and shall comply with one of the following standards:
1. ASME B36.10, 10M.
2. ASTM A 53/A53M.
3. ASTM A 106.
1. ASME B36.10, 10M.
2. ASTM A 53/A53M.
3. ASTM A 106.
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 of gas (0.7 milligrams per 100 liters). Threaded copper, copper alloy and aluminum-alloy pipe shall not be used with gases corrosive to such materials.
Aluminum-alloy pipe shall comply with ASTM B 241 except that the use of alloy 5456 is prohibited. Aluminum-alloy pipe 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 or insulation, or is subject to repeated wettings by such liquids as water, detergents or sewage. Aluminum-alloy pipe shall not be used in exterior locations or underground.
Seamless copper, aluminum alloy and steel tubing shall not be used with gases corrosive to such materials.
Steel tubing shall comply with ASTM A 254.
Copper tubing shall comply with Standard Type K or L of ASTM B 88 or ASTM B 280.
Copper and copper alloy tubing shall not be used if the gas contains more than an average of 0.3 grains of hydrogen sulfide per 100 standard cubic feet of gas (0.7 milligrams per 100 liters).
Copper and copper alloy tubing shall not be used if the gas contains more than an average of 0.3 grains of hydrogen sulfide per 100 standard cubic feet of gas (0.7 milligrams per 100 liters).
Aluminum-alloy tubing shall comply with ASTM B 210 or ASTM B 241. Aluminumalloy tubing shall be coated to protect against external corrosion where it is in contact with masonry, plaster or 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.
Aluminum-alloy tubing shall not be used in exterior locations or underground.
Corrugated stainless steel tubing shall be listed in accordance with ANSI LC 1/CSA 6.26.
Polyethylene plastic pipe, tubing and fittings used to supply fuel gas shall conform to ASTM D 2513. Such pipe shall be marked “Gas” and “ASTM D 2513.”
Plastic pipe, tubing and fittings, other than polyethylene, shall be identified and conform to the 2008 edition of ASTM D 2513. Such pipe shall be marked “Gas” and “ASTM D 2513.”
Polyvinyl chloride (PVC) and chlorinated polyvinyl chloride (CPVC) plastic pipe, tubing and fittings shall not be used to supply fuel gas.
Plastic pipe, tubing and fittings, other than polyethylene, shall be identified and conform to the 2008 edition of ASTM D 2513. Such pipe shall be marked “Gas” and “ASTM D 2513.”
Polyvinyl chloride (PVC) and chlorinated polyvinyl chloride (CPVC) plastic pipe, tubing and fittings shall not be used to supply fuel gas.
Plastic pipe, tubing and 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 designed and certified to meet the requirements of Category I of ASTM D 2513, and U.S. Department of Transportation, Code of Federal Regulations, Title 49, Part 192.281(e). The manufacturer shall provide the user with qualified installation instructions as prescribed by the U.S. Department of Transportation, Code of Federal Regulations, Title 49, Part 192.283(b).
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 designed and certified to meet the requirements of Category I of ASTM D 2513, and U.S. Department of Transportation, Code of Federal Regulations, Title 49, Part 192.281(e). The manufacturer shall provide the user with qualified installation instructions as prescribed by the U.S. Department of Transportation, Code of Federal Regulations, Title 49, Part 192.283(b).
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.
Field threading of metallic pipe shall be in accordance with Table 403.9.2.
TABLE 403.9.2 SPECIFICATIONS FOR THREADING METALLIC PIPE
TABLE 403.9.2 SPECIFICATIONS FOR THREADING METALLIC PIPE
| 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: 1 inch = 25.4 mm.
Thread joint compounds shall be resistant to the action of liquefied petroleum gas or to any other chemical constituents of the gases to be conducted through the piping.
The type of piping joint used shall be suitable for the pressure-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 caused by the internal pressure and any additional forces caused by temperature expansion or contraction, vibration, fatigue or the weight of the pipe and its contents.
Metallic fittings shall comply with the following:
1. Threaded fittings in sizes larger than 4 inches (102 mm) shall not be used.
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:
5.1. Flanges shall be permitted.
5.2. Bushings shall not be used.
5.3. Fittings shall not be used in systems containing flammable gas-air mixtures.
5.4. Fittings in sizes 4 inches (102 mm) and larger shall not be used indoors except where approved.
5.5. Fittings in sizes 6 inches (152 mm) and larger shall not be used except where approved.
6. Aluminum-alloy fittings. Threads shall not form the joint seal.
7. Zinc aluminum-alloy fittings. Fittings shall not be used in systems containing flammable gas-air mixtures.
8. Special fittings. Fittings such as couplings, proprietary-type joints, saddle tees, gland-type compression fittings and flared, flareless and compression-type tubing fittings shall be: used within the fitting manufacturer’s pressure-temperature recommendations; used within the service conditions anticipated with respect to vibration, fatigue, thermal expansion and contraction; and shall be approved.
9. Where pipe fittings are drilled and tapped in the field, the operation shall be in accordance with all of the following:
9.1. The operation shall be performed on systems having operating pressures of 5 psi (34.5 kPa) or less.
9.2. The operation shall be performed by the gas supplier or the gas supplier’s designated representative.
9.3. The drilling and tapping operation shall be performed in accordance with written procedures prepared by the gas supplier.
9.4. The fittings shall be located outdoors.
9.5. The tapped fitting assembly shall be inspected and proven to be free of leakage.
1. Threaded fittings in sizes larger than 4 inches (102 mm) shall not be used.
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:
5.1. Flanges shall be permitted.
5.2. Bushings shall not be used.
5.3. Fittings shall not be used in systems containing flammable gas-air mixtures.
5.4. Fittings in sizes 4 inches (102 mm) and larger shall not be used indoors except where approved.
5.5. Fittings in sizes 6 inches (152 mm) and larger shall not be used except where approved.
6. Aluminum-alloy fittings. Threads shall not form the joint seal.
7. Zinc aluminum-alloy fittings. Fittings shall not be used in systems containing flammable gas-air mixtures.
8. Special fittings. Fittings such as couplings, proprietary-type joints, saddle tees, gland-type compression fittings and flared, flareless and compression-type tubing fittings shall be: used within the fitting manufacturer’s pressure-temperature recommendations; used within the service conditions anticipated with respect to vibration, fatigue, thermal expansion and contraction; and shall be approved.
9. Where pipe fittings are drilled and tapped in the field, the operation shall be in accordance with all of the following:
9.1. The operation shall be performed on systems having operating pressures of 5 psi (34.5 kPa) or less.
9.2. The operation shall be performed by the gas supplier or the gas supplier’s designated representative.
9.3. The drilling and tapping operation shall be performed in accordance with written procedures prepared by the gas supplier.
9.4. The fittings shall be located outdoors.
9.5. The tapped fitting assembly shall be inspected and proven to be free of leakage.
Plastic pipe, tubing and fittings shall be joined in accordance with the manufacturer’s instructions. Such joint shall comply with the following:
1. 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.
2. Heat-fusion joints shall be made in accordance with qualified procedures that have been established and proven by test to produce gas-tight joints at least 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 D 2513.”
3. 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 at least to the outside end of the compression fitting when installed. The stiffener shall be free of rough or sharp edges and shall not be a force fit in the plastic. Split tubular stiffeners shall not be used.
4. Plastic piping joints and fittings for use in liquefied petroleum gas piping systems shall be in accordance with NFPA 58.
1. 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.
2. Heat-fusion joints shall be made in accordance with qualified procedures that have been established and proven by test to produce gas-tight joints at least 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 D 2513.”
3. 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 at least to the outside end of the compression fitting when installed. The stiffener shall be free of rough or sharp edges and shall not be a force fit in the plastic. Split tubular stiffeners shall not be used.
4. Plastic piping joints and fittings for use in liquefied petroleum gas piping systems shall be in accordance with NFPA 58.
Cast-iron flanges shall be in accordance with ASME B 16.1.
Steel flanges shall be in accordance with ASME B 16.5 or ASME B 16.47.
Nonferrous flanges shall be in accordance with ASME B 16.24.
Ductile-iron flanges shall be in accordance with ASME B 16.42.
Raised face flanges shall not be joined to flat faced cast-iron, ductile-iron or nonferrous material flanges.
Standard facings shall be permitted for use under this code. Where 150-pound (1034 kPa) pressure-rated steel flanges are bolted to Class 125 cast-iron flanges, the raised face on the steel flange shall be removed.
Lapped flanges shall be used only above ground or in exposed locations accessible for inspection.
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 material. Acceptable materials include metal (plain or corrugated), composition, aluminum “O” rings, spiral wound metal gaskets, rubber-faced phenolic and elastomeric. Where a flanged joint is opened, the gasket shall be replaced. Full-face flange gaskets shall be used with all nonsteel flanges.
Metallic flange gaskets shall be in accordance with ASME B 16.20.
Nonmetallic flange gaskets shall be in accordance with ASME B 16.21.