CPC · California Plumbing Code
Fuel Gas Piping
Chapter 12 of the California Plumbing Code sets the scope, materials, inspection, testing/purging, and sizing rules for building fuel gas piping systems.
Last reviewed: July 6, 2026
Overview
This part of the California Plumbing Code (CPC) is Chapter 12 and governs the installation, materials, testing, inspection, and sizing of fuel gas piping for buildings and premises — generally up to 5 psi for natural gas and 10 psi for undiluted propane as defined in §1201.1 . It defines the coverage of a piping system from the point of delivery to appliance connections and sets the scope of what is and is not included in the chapter (§1202.1) .
The chapter also contains the inspection and testing requirements (including rough and final inspections) and procedures for pressure testing and purging of piping (§1203.0, §1213.1.6) file. Key technical rules include allowable piping materials and special provisions (for example §1208.5 on plastic, CSST and anodeless risers) and pipe-sizing and engineering methods used to determine system capacities (§1208.5, §1215.4) file.
In this section
Code references
Grounded in the retrieved California Plumbing Code — click a citation to read the verbatim passage:
CPC § 1201.1 High relevance — show source text
8_||||||||||||||||||||||||| |Adopting Agency
Adopt Entire Chapter
Adopt Entire Chapter as
amended (amended
sections listed below)
Adopt only those sections
that are listed below
Chapter/Section
1201.1
1211.8||||||||||||||||||||||||| |Adopting Agency
Adopt Entire Chapter
Adopt Entire Chapter as
amended (amended
sections listed below)
Adopt only those sections
that are listed below
Chapter/Section
1201.1
1211.8|||X|||||||||||||||||||||| |Adopting Agency
Adopt Entire Chapter
Adopt Entire Chapter as
amended (amended
sections listed below)
Adopt only those sections
that are listed below
Chapter/Section
1201.1
1211.8|||X|||||X|X||||||||||||||||This state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.0.
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CHAPTER 12
FUEL GAS PIPING
1201.0 General.
1201.1 Applicability. 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 connected to oil- burning equipment shall be installed in accordance with NFPA 31. Fuel oil piping systems connected to internal com- bustion engines and gas turbines shall be installed in accor- dance with NFPA 37.
1202.0 Coverage of Piping System. 1202.1 General. 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)] 1202.2 Piping System Requirements. Requirements for piping systems shall include design, materials, components, fabrication, assembly, installation, testing, inspection, operation, and maintenance. [NFPA 54:1.1.1.1(E)] 1202.3 Applications. This chapter shall not apply to the following items:
CPC § 304.8 High relevance — show source text
NOMINAL PIPING SIZE
(inches)LENGTH OF PIPING
(feet)
≥ 21⁄2 < 3> 50
≥ 3 < 4> 30
≥ 4 < 6> 15
≥ 6 < 8> 10
≥ 8Any 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.
1213.6.1.1 Removal from Service. 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]
1213.6.1.2 Removal of Piping. 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.
1213.6.1.3 Placing in Operation. Where gas piping containing air and meeting the criteria of Table
TABLE 1213.6.1
SIZE AND LENGTH OF PIPING
[NFPA 54: TABLE 8.3.1]*
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.
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FUEL GAS PIPING
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]
1213.6.1.4 Outdoor Discharge of Purged Gases. The open end of a piping system being pressure vented or purged shall discharge directly to an outdoor location. Purging operations shall comply with all of 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 complies with Section 1213.6.1.5.
(4) Purging operations introducing fuel gas shall be stopped when 90 percent fuel gas by volume is detected within the pipe.
CPC § 0.249 High relevance — show source text
water column = 0.249 kPa
TABLE 1215.3
Cr AND Y FOR NATURAL GAS AND UNDILUTED
PROPANE AT STANDARD CONDITIONS
[NFPA 54: TABLE 6.4.2]
GAS FORMULA FACTORS Col3
GASCr Y
Natural Gas0.6094 0.9992 Undiluted Propane 1.2462 0.9910 1215.4 Sizing of Piping Sections. To determine the size of each section of pipe in a system within the range of Table 1215.2(1) through Table 1215.2(36), proceed as follows:
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FUEL GAS PIPING
(1) Measure the length of the pipe from the gas meter location to the most remote outlet on the system.
(2) Select the length in feet column and row showing the distance, or the next longer distance where the table does not give the exact length.
(3) Starting at the most remote outlet, find in the row just selected the gas demand for that outlet. Where the exact figure of demand is not shown, choose the next larger figure in the row.
(4) At the top of this column will be found the correct size of pipe.
(5) Using this same row, proceed in a similar manner to each section of pipe serving this outlet. For each section of pipe, determine the total gas demand supplied by that section. Where gas piping sections serve both heating and cooling appliances and the installation prevents both units from operating simultaneously, the larger of the two demand loads needs to be used in sizing these sections.
(6) Size each section of branch piping not previously sized by measuring the distance from the gas meter location to the most remote outlet in that branch and follow the procedures of steps 2, 3, 4, and 5 above. Size branch piping in the order of their distance from the meter location, beginning with the most distant outlet not previously sized.
1215.5 Engineering Methods. For conditions other than those covered by Section 1215.1, such as longer runs or greater gas demands, the size of each gas piping system shall be determined by standard engineering methods acceptable to the Authority Having Jurisdiction, and each such system shall be so designed that the total pressure drop between the meter or another point of supply and an outlet where full demand is being supplied to all outlets, shall be in accordance with the requirements of Section 1208.4. 1215.6 Variable Gas Pressure. Where the supply gas pressure exceeds 5 psi (34.6 kPa) for natural gas and 10 psi (69 kPa) for undiluted propane or is less than 6 inches (1.5 kPa) of water column, or where diversity demand factors are used, the design, pipe, sizing, materials, location, and use of such systems first shall be approved by the Authority Having Jurisdiction. Piping systems designed for pressures exceeding the serving gas supplier’s standard delivery pressure shall have prior verification from the gas supplier of the availability of the design pressure.
CPC § 1201.0 High relevance — show source text
1201.0 General.
1201.1 Applicability. 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 connected to oil- burning equipment shall be installed in accordance with NFPA 31. Fuel oil piping systems connected to internal com- bustion engines and gas turbines shall be installed in accor- dance with NFPA 37.
1202.0 Coverage of Piping System. 1202.1 General. 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)] 1202.2 Piping System Requirements. Requirements for piping systems shall include design, materials, components, fabrication, assembly, installation, testing, inspection, operation, and maintenance. [NFPA 54:1.1.1.1(E)] 1202.3 Applications. This chapter shall not apply to the following items:
(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.
CPC § 8.3.1 High relevance — show source text
[NFPA 54: TABLE 8.3.1]*
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.
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FUEL GAS PIPING
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]
1213.6.1.4 Outdoor Discharge of Purged Gases. The open end of a piping system being pressure vented or purged shall discharge directly to an outdoor location. Purging operations shall comply with all of 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 complies with Section 1213.6.1.5.
(4) Purging operations introducing fuel gas shall be stopped when 90 percent fuel gas by volume is detected within the pipe.
(5) Persons not involved in the purging operations shall be evacuated from all areas within 10 feet
(3048 mm) of the point of discharge. [NFPA 54:8.3.1.3]
1213.6.1.5 Combustible Gas Indicator. Com bustible 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]
1213.6.2 Piping Systems Allowed to be Purged Indoors or Outdoors. 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 kPag) 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]
1213.6.2.1 Purging Procedure. 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.
CPC § 1208.3.1 High relevance — show source text
TABLE 1208.3.1
APPROXIMATE GAS INPUT FOR
TYPICAL APPLIANCES
[NFPA 54: TABLE A.5.3.2.1]
«
«
«
«
«
For SI units: 1000 British thermal units per hour = 0.293 kW
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FUEL GAS PIPING
«
«
«
«
«
«
«
«
«
«
1208.5.4 Plastic Pipe, Tubing, and Fittings. 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.” Polyamide pipe, tubing, and fittings shall be identified in and conform to ASTM F2945. Pipe to be used shall be marked “gas” and “ASTM F2945.” Polyvinyl chloride (PVC) and chlorinated polyvinyl chloride (CPVC) plastic pipe, tubing, and fittings shall not be used to supply fuel gas. [NFPA 54:5.5.4.1.1 – 5.5.4.1.3]
1208.5.5 Regulator Vent Piping. Plastic pipe and fittings used to connect regulator vents to remote vent terminations shall be PVC (Schedule 40 and 80). PVC vent piping shall not be installed indoors. {NFPA 54:5.5.4.2}
1208.5.6 Anodeless Risers. Anodeless risers shall
comply with Section 1208.5.6.1 through Section 1208.5.6.3.
1208.5.6.1 Factory-Assembled Anodeless Risers. 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. [NFPA 54:5.5.4.3(1)]
1208.5.6.2 Service Head Adapters and Field- Assembled Anodeless Risers. 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 meet the requirements of Category I of ASTM D2513 and 49 CFR 192.281(e). The manufacturer shall provide the user qualified installation instructions as prescribed by 49 CFR 192.283(b).
[NFPA 54:5.5.4.3(2)]
1208.5.6.3 Undiluted Liquefied Petroleum Gas Piping. The use of plastic pipe, tubing, and fittings in undiluted LP-Gas piping systems shall be in accordance with NFPA 58. [NFPA 54:5.5.4.3(3)]
CPC § 404.3 High relevance — show source text
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APPENDIX E
E 404.3 Mechanical Protection. All gas outlet risers, regulators, meters, valves, and other exposed equipment shall be protected against accidental damage. [NFPA 501A:4.4.3]
E 404.4 Special Rules on Atmospherically Con- trolled Regulators. Atmospherically controlled regulators shall be installed in such a manner that moisture cannot enter the regulator vent and accumulate above the diaphragm. Where the regulator vent is obstructed due to snow and icing conditions, shields, hoods, or other suitable devices shall be provided to guard against closing of the vent opening. [NFPA 501A:4.4.4.1 – 4.4.4.2]
E 404.5 Fuel Gas Piping Test. The manufactured home fuel gas piping system shall be tested only with air before it is connected to the gas supply. The manufactured home gas piping system shall be subjected to a pressure test with all appliance shutoff valves in their closed positions. [NFPA 501A:4.4.5]
E 404.5.1 Procedures. The fuel gas piping test shall consist of air pressure at not less than 10 inches water column or more than 14 inches water column (2.5 kPa to 3.5 kPa). The fuel gas piping system shall be isolated from the air pressure source and shall maintain this pressure for not less than 10 minutes without perceptible leakage. Upon satisfactory completion of the fuel gas piping test, the appliance valves shall be opened, and the gas appliance connectors shall be tested with soapy water or bubble solution while under the pressure remaining in the piping system. Solutions used for testing for leakage shall not contain corrosive chemicals. Pressure shall be measured with a manometer, slope gauge, or gauge that is calibrated in either water inch (mm) or psi (kPa) with increments of either [1] ⁄ 10 inch (2.5 mm) or [1] ⁄ 10 psi (0.7 kPa) gauge, as applicable. Upon satisfactory completion of the fuel gas piping test, the manufactured home gas supply connector shall be installed, and the connections shall be tested with soapy water or bubble solution. [NFPA 501A:4.4.5.1.1 – 4.4.5.1.6]
E 404.5.2 Warning. The following warning shall be supplied to the installer:
WARNING: Do not overpressurize the fuel gas piping system. Damage to valves, regulators, and appliances can occur due to pressurization beyond the maximums specified. [NFPA 501A:4.4.5.2]
E 404.5.3 Vents. Gas appliance vents shall be visually inspected to ensure that they have not been dislodged in transit and are connected securely to the appliance.
[NFPA 501A:4.4.5.3]
E 404.6 Oil Tanks. Oil tank capacities shall comply with the following:
(1) No more than one 660 gallon (2498 L) tank or two tanks with an aggregate capacity of 660 gallons (2498 L) or less shall be connected to one oil-burning appliance.
CPC § 1213.6.2.1 High relevance — show source text
1213.6.2.1 Purging Procedure. 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 pur pose.
(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 when 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]
1213.6.2.2 Combustible Gas Detector. Com bustible 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]
1213.6.3 Purging Appliances and Equipment. 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]
1214.0 Required Gas Supply.
1214.1 General. 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.
1214.2 Volume. 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.
1214.3 Gas Appliances. Where the gas appliances to be installed have not been specified, Table 1208.3.1 shall be permitted to be used as a reference to estimate requirements of typical appliances. To obtain the cubic feet per hour (m [3] /h) of gas required, divide the input of the appliances by the average Btu (kW•h) heating value per cubic foot (m [3] ) of the gas. The average Btu (kW•h) per cubic foot (m [3] ) of the gas in the area of the installation shall be permitted to be obtained from the serving gas supplier.
1214.4 Size of Piping Outlets. 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).
CPC § 4.2.1 High relevance — show source text
1101.4.2.1, 1104.4.2.2
AIR GAPS
Backflow prevention . . . . . . 603.2, Table 603.2, 603.3.1, Table 603.3.1, 603.4.4
Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203.0
Discharge from drinking
water treatment units . . . . . . . . . . . . . . . . . . . . . 611.2
AIR TANK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .710.11
ALTERATIONS AND REPAIRS
Fuel gas piping . . . . . . . . . . . .1203.1, 1213.1.2, 1213.4.2
Health care facilities . . . . . . . . . . . . . . . . . . . . . . .1301.5
Plumbing systems . . . . . . . . . . . . . . . . . .102.4, 301.2.5 ALTERNATE MATERIALS, DESIGN,
AND METHODS . . . . . . . . . . . . . . . . . . . . . . . . . . . .301.3
ALTERNATE WATER SOURCE
Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .203.0
For nonpotable applications . . .Chapter 15, Chapter 16 For special water features . . . . . . . . . . . . . . . . .L 406.1
Future connections . . . . . . . . . . . . . . . . . . . . .1504.9.1
Identification of piping . . . . . . . . . . . . . . . . . . . . .601.3.3 Nonpotable rainwater catchment system . . . . . . . . . . .Table 1601.5, 1602.4
Potable rainwater
catchment system . . . . . . . . . . . . . . . . . . . . . .K 102.2 ANODELESS RISER, DEFINITION . . . . . . . . . . . . . . .203.0
APPLIANCES
Automatically operated . . . . . . . . . . . .509.3.4, 509.5.7.1 Categorized vent diameter/area, definition . . . . . . . . . . . . . . . . . .203.0 Connections to building fuel gas piping . . . . . . . . . . . . . . . . . . . . . . . . .1212.0
Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .203.0
Direct-vent . . . . . . . . . . . . . . . .206.0, 509.2.6, 509.5.10.1,
509.8.1, 509.12
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CPC § 8.3.1.1 High relevance — show source text
[NFPA 54:8.3.1.1] 1313.6.1.2 Placing in Operation. Where gas piping containing air and meeting the criteria of Table 1313.6.1 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 1313.6.1.3. [NFPA 54:8.3.1.2] 1313.6.1.3 Outdoor Discharge of Purged Gases. The open end of a piping system being pressure vented or purged shall discharge directly to an outdoor location. Purging operations shall comply with all of 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 complies with Section 1313.6.1.4.
(4) Purging operations introducing fuel gas shall be stopped when 90 percent fuel gas by volume is detected within the pipe. (5) Persons not involved in the purging operations shall be evacuated from all areas within 10 feet (3048 mm) of the point of discharge. [NFPA 54:8.3.1.3]
1313.6.1.4 Combustible Gas Indicator. 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]
1313.6.2 Piping Systems Allowed to be Purged Indoors or Outdoors. The purging of piping systems shall be in accordance with the provisions of Section 1313.6.2.1 where the piping system meets both of the following: (1) The design operating pressure is 2 psig (14 kPag) or less.
(2) The piping being purged is constructed entirely from pipe or tubing not meeting the size and length criteria of Table 1313.6.1. [NFPA 54:8.3.2] 1313.6.2.1 Purging Procedure. 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 1313.6.2.2. Purging shall be stopped when fuel gas is detected.
CPC § 1313.6.2 Medium relevance — show source text
1313.6.2 Piping Systems Allowed to be Purged Indoors or Outdoors. The purging of piping systems shall be in accordance with the provisions of Section 1313.6.2.1 where the piping system meets both of the following: (1) The design operating pressure is 2 psig (14 kPag) or less.
(2) The piping being purged is constructed entirely from pipe or tubing not meeting the size and length criteria of Table 1313.6.1. [NFPA 54:8.3.2] 1313.6.2.1 Purging Procedure. 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 1313.6.2.2. Purging shall be stopped when 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] 1313.6.2.2 Combustible Gas Detector. 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] 1313.6.3 Purging Appliances and Equipment. 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]
1314.0 Required Gas Supply. 1314.1 General. The following regulations, shall comply with this section and Section 1315.0, shall be the standard for the installation of gas piping. Natural gas regulations and tables are based on the use of 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 serving gas supplier shall be permitted to be contacted for specific gravity conversion factors to use in sizing piping systems from the pipe sizing tables in this chapter. 1314.2 Volume. 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.
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FUEL GAS PIPING
CPC § 8.1.1.6 Medium relevance — show source text
[NFPA 54:8.1.1.6] 1213.1.6 Test Medium. The test medium shall be air, nitrogen, carbon dioxide, or an inert gas. Oxygen shall not be used as a test medium. [NFPA 54:8.1.2] 1213.2 Test Preparation. Test preparation shall comply with Section 1213.2.1 through Section 1213.2.6. 1213.2.1 Pipe Joints. 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] 1213.2.2 Expansion Joints. Expansion joints shall be provided with temporary restraints, if required, for the additional thrust load under test. [NFPA 54:8.1.3.2] 1213.2.3 Appliances and Equipment. 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] 1213.2.4 Designed for Operating Pressures Less Than Test Pressure. 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] 1213.2.5 Designed for Operating Pressures Equal to or Greater Than Test Pressure. Where the piping system is connected to appliances or equipment designed
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FUEL GAS PIPING
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]
1213.2.6 Safety. 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]
1213.3 Test Pressure. This inspection shall include an air, CO 2, 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.
Frequently asked questions
What pressures and fuels does Chapter 12 cover?
Chapter 12 covers building piping systems up to 5 psi for natural gas and up to 10 psi for undiluted propane, per §1201.1 .
Where are the CPC rules for testing and purging gas piping?
Testing, test pressures, permitted test media, and purge procedures are in the Chapter 12 testing and purging provisions (see §1213 and related subsections, including §1213.1.6 and the outdoor discharge requirements) file.
Where do I find sizing and permitted materials?
Pipe-sizing tables and methods are in §1215 (with procedures in §1215.4), and permitted piping materials plus special material rules (CSST, plastic, anodeless risers) are in §1208.5 and related sections file.
More in California Plumbing Code
- Administration
- Alternate Water Sources and Nonpotable Rainwater Catchment Systems
- Definitions
- Fuel Gas Piping
- General Regulations
- Health Care Facilities — Medical Gas and Medical Vacuum Systems
- Indirect Wastes
- Plumbing Fixtures and Fixture Fittings
- Sanitary Drainage (Drain, Waste, and Vent)
- Storm Drainage
- Traps and Interceptors
- Vents
- Water Heaters
- Water Supply and Distribution
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