CPC · California Plumbing Code
Testing, purging, repairs, and placing piping into service
This hub summarizes CPC rules for pressure testing, leak detection and repairs, purging procedures, and the conditions for placing piping and connected equipment into service.
Last reviewed: July 6, 2026
Overview
This part of the California Plumbing Code (CPC) covers requirements for pressure testing, visual inspection, leak detection and repair, purging, and the conditions for placing piping and connected appliances into service. It establishes how piping systems (especially fuel‑gas systems) must be tested and verified—what media may be used, how joints and appliances are isolated, and when the Authority Having Jurisdiction (AHJ) must witness tests—so systems are safe before fuel or service gases are introduced. See the CPC pressure‑testing and inspection provisions at §1213.0–§1213.2 for test preparation and media and the requirement that tests be conducted in the presence of the AHJ.
Purging rules (when, where, and how to vent or displace air or residual gas) are covered in §1213.6 and its subparts, including the size/length criteria in Table 1213.6.1 and outdoor discharge controls, monitoring, and safety distances for purging operations. These provisions also explain the sequence for displacing air with inert gas and then fuel gas before placing a system in operation.
The scope also includes related, specialized testing and purge rules: medical gas systems have separate initial purge and standing‑pressure test requirements (for example §1324.5 and §1321.10) and potable‑water piping must be disinfected and flushed per the CPC before being used (see §1324.5 and §609.10). Where leaks or defects are found, the code requires repair or replacement and retesting before acceptance.
In this section
Code references
Grounded in the retrieved California Plumbing Code — click a citation to read the verbatim passage:
CPC § 1213.5.2 High relevance — show source text
1213.5.2 Leak Check. 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 leak
age is indicated, the gas supply shall be shut off until the necessary repairs have been made. [NFPA 54:8.2.3]
1213.5.3 Placing Appliances and Equipment in Operation. Appliances and equipment shall not be placed in operation until after the piping system has been checked for leakage in accordance with Section 1213.5.2, the piping system is purged in accordance with Section 1213.6, and connections to the appliance are checked for leakage. [NFPA 54:8.2.4]
1213.6 Purging Requirements. The purging of piping shall be in accordance with Section 1213.6.1 through Section 1213.6.3. [NFPA 54:8.3]
1213.6.1 Piping Systems Required to be Purged Outdoors. The purging of piping systems shall be in accordance with 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
≥ 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
CPC § 318.0. High relevance — show source text
These tests shall be made using air, CO 2, 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.
1213.4 Detection of Leaks and Defects. 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]
1213.4.1 Detecting Leaks. 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]
1213.4.2 Repair or Replace. 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]
1213.5 Piping System Leak Test. Leak checks using fuel gas shall be permitted in piping systems that have been pressure-tested in accordance with Section 1213.0 through Section 1213.4.2. [NFPA 54:8.2.1]
1213.5.1 Turning Gas On. 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 all valves at unused outlets are closed and plugged or capped. [NFPA 54:8.2.2]
1213.5.2 Leak Check. 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 leak
age is indicated, the gas supply shall be shut off until the necessary repairs have been made. [NFPA 54:8.2.3]
1213.5.3 Placing Appliances and Equipment in Operation. Appliances and equipment shall not be placed in operation until after the piping system has been checked for leakage in accordance with Section 1213.5.2, the piping system is purged in accordance with Section 1213.6, and connections to the appliance are checked for leakage. [NFPA 54:8.2.4]
1213.6 Purging Requirements. The purging of piping shall be in accordance with Section 1213.6.1 through Section 1213.6.3. [NFPA 54:8.3]
1213.6.1 Piping Systems Required to be Purged Outdoors. The purging of piping systems shall be in accordance with 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
CPC § 1303.3.3.1 High relevance — show source text
Necessary apparatus for conducting tests shall be furnished by the permit holder. Test gauges used in conducting test shall be in accordance with Section 1303.3.3.1 through Section 1303.3.3.4. 1313.4 Detection of Leaks and Defects. 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] 1313.4.1 Detecting Leaks. 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] 1313.4.2 Repair or Replace. 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] 1313.5 Piping System Leak Test. Leak checks using fuel gas shall be permitted in piping systems that have been pressure-tested in accordance with Section 1313.0 through Section 1313.4.2. [NFPA 54:8.2.1] 1313.5.1 Turning Gas On. 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 all valves at unused outlets are closed and plugged or capped. [NFPA 54:8.2.2] 1313.5.2 Leak Check. 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]
1313.5.3 Placing Appliances and Equipment in Operation. Appliances and equipment shall not be placed in operation until after the piping system has been checked for leakage in accordance with Section 1313.5.2, the piping system is purged in accordance with Section 1313.6, and connections to the appliance are checked for leakage. [NFPA 54:8.2.4]
1313.6 Purging Requirements. The purging of piping shall be in accordance with Section 1313.6.1 through Section 1313.6.3. [NFPA 54:8.3]
1313.6.1 Piping Systems Required to be Purged Outdoors. The purging of piping systems shall be in accordance with Section 1313.6.1.1 through Section 1313.6.1.4 where the piping system meets either of the following:
(1) The design operating gas pressure is greater than 2 psig (14 kPag).
(2) The piping being purged contains one or more sections of pipe or tubing meeting the size and length criteria of Table 1313.6.1. [NFPA 54:8.3.1]
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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 § 1324.5.2.3 High relevance — show source text
1324.5.2.3 System to Be Charged. The system under test shall be charged with oil-free, dry nitrogen NF to a gauge pressure of 50 psi (345 kPa).
[NFPA 99:5.1.12.2.4.3]
1324.5.2.4 Check Outlets and Inlets. After the
installation of the individual faceplates with appropriate adapters matching outlet/inlet labels, each individual outlet/inlet in each installed medical gas and vacuum piping system shall be checked to determine that the test gas is being dispensed only from the piping system being tested. [NFPA 99:5.1.12.2.4.4]
1324.5.2.5 Repeat Test. The cross-connection test referenced in Section 1324.5.2 shall be repeated for each installed medical gas and vacuum piping system. [NFPA 99:5.1.12.2.4.5]
1324.5.2.6 Identification of System. The proper labeling and identification of system outlets/inlets shall be confirmed during these tests. [NFPA 99:5.1.12.2.4.6]
1324.5.3 Initial Piping Purge Tests. The outlets in each medical gas piping system shall be purged to remove any particulate matter from the distribution piping. [NFPA 99:5.1.12.2.5]
1324.5.3.1 Procedure. Using appropriate adapters, each outlet shall be purged with an intermittent high-volume flow of test gas until the purge produces no discoloration in a clean white cloth.
[NFPA 99:5.1.12.2.5.1]
1324.5.3.2 Location. The purging required in Section 1324.5.3.1 shall be started at the closest out let/inlet to the zone valve and continue to the furthest outlet/inlet within the zone. [NFPA 99:5.1.12.2.5.2]
1324.5.4 Standing Pressure Tests – for Positive Pressure Medical Gas Piping Systems. After successful completion of the initial pressure tests under Section 1324.5 through Section 1324.5.1.2, medical gas distribution piping shall be subjected to a standing pressure test. [NFPA 99:5.1.12.2.6]
1324.5.4.1 Time Frame for Testing. Tests shall be conducted after the final installation of station outlet valve bodies, faceplates, and all other distribution system components. [NFPA 99:5.1.12.2.6.1]
1324.5.4.2 Source Valve. The source valve shall be closed during this test. [NFPA 99:5.1.12.2.6.2]
1324.5.4.3 Length of Testing. The piping systems shall be subjected to a 24-hour standing pressure test using oil-free, dry nitrogen NF. [NFPA 99:5.1.12.2.6.3]
1324.5.4.4 Test Pressure. Test pressures shall be 20 percent above the normal system operating line pressure. [NFPA 99:5.1.12.2.6.4]
CPC § 1324.5.1.1 High relevance — show source text
1324.5.1.1 Required Test Pressure. The test pressure for pressure gases and vacuum systems shall be 1.5 times the system operating pressure but not less than a gauge pressure of 150 psi (1034 kPa). The test pressure shall be maintained until each joint has been examined for leakage by means of a leak detectant that is safe for use with oxygen and does not contain ammonia. [NFPA 99:5.1.12.2.3.4, 5.1.12.2.3.5]
1324.5.1.2 Leaks. Leaks, if any, shall be located, repaired (if permitted), replaced (if required), and retested. [NFPA 99:5.1.12.2.3.6]
1324.5.2 Initial Cross-Connection Test. It shall be
determined that no cross-connections exist between the
various medical gas and vacuum piping systems. [NFPA 99:5.1.12.2.4]
1324.5.2.1 Atmospheric Pressure. All piping systems shall be reduced to atmospheric pressure.
[NFPA 99:5.1.12.2.4.1]
1324.5.2.2 Sources of Test Gas. Sources of test
gas shall be disconnected from all piping systems, except for the one system being tested. [NFPA 99:5.1.12.2.4.2]
1324.5.2.3 System to Be Charged. The system under test shall be charged with oil-free, dry nitrogen NF to a gauge pressure of 50 psi (345 kPa).
[NFPA 99:5.1.12.2.4.3]
1324.5.2.4 Check Outlets and Inlets. After the
installation of the individual faceplates with appropriate adapters matching outlet/inlet labels, each individual outlet/inlet in each installed medical gas and vacuum piping system shall be checked to determine that the test gas is being dispensed only from the piping system being tested. [NFPA 99:5.1.12.2.4.4]
1324.5.2.5 Repeat Test. The cross-connection test referenced in Section 1324.5.2 shall be repeated for each installed medical gas and vacuum piping system. [NFPA 99:5.1.12.2.4.5]
1324.5.2.6 Identification of System. The proper labeling and identification of system outlets/inlets shall be confirmed during these tests. [NFPA 99:5.1.12.2.4.6]
1324.5.3 Initial Piping Purge Tests. The outlets in each medical gas piping system shall be purged to remove any particulate matter from the distribution piping. [NFPA 99:5.1.12.2.5]
1324.5.3.1 Procedure. Using appropriate adapters, each outlet shall be purged with an intermittent high-volume flow of test gas until the purge produces no discoloration in a clean white cloth.
[NFPA 99:5.1.12.2.5.1]
CPC § 1312.7 High relevance — show source text
1312.7 Quick-Disconnect Devices. Quick-disconnect devices used to connect appliances to the building piping shall be listed in accordance with ANSI Z21.41/CSA 6.9.
Where installed indoors, an approved manual shutoff valve with a nondisplaceable valve member shall be installed upstream of the quick-disconnect device. [NFPA 54:9.6.6 – 9.6.6.2]
1312.8 Gas Convenience Outlets. 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/ANSI Z21.90/CSA 6.24 and installed in accor dance with the manufacturer’s installation instructions.
[NFPA 54:9.6.7]
1312.9 Sediment Trap. 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 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 1312.9, or another device recognized as an effective sediment trap. Illuminating appliances, gas ranges, clothes dryers, decorative appliances for installation in vented fireplaces, gas fireplaces, and outdoor cooking appliances shall not be required to be so equipped. [NFPA 54:9.6.8]
For SI units: 1 inch = 25.4 mm
FIGURE 1312.9
METHOD OF INSTALLING A TEE FITTING SEDIMENT TRAP
[NFPA 54: FIGURE 9.6.8]
1312.10 Installation of Piping. Piping shall be installed in a manner not to interfere with inspection, maintenance, or servicing of the appliances. [NFPA 54:9.6.9] 1312.11 Liquefied Petroleum Gas (LP-Gas) Facilities and Piping. Liquefied petroleum gas (LP-Gas) facilities shall comply with NFPA 58.
1313.0 Pressure Testing, Inspection, and Purging. 1313.1 Piping Installations. 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] 1313.1.1 Inspection Requirements. Inspection shall consist of visual examination, during or after manufacture, fabrication, assembly, or pressure tests. [NFPA 54:8.1.1.2] 1313.1.2 Repairs and Additions. 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]
CPC § 8.2.3 High relevance — show source text
** 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]
1313.5.3 Placing Appliances and Equipment in Operation. Appliances and equipment shall not be placed in operation until after the piping system has been checked for leakage in accordance with Section 1313.5.2, the piping system is purged in accordance with Section 1313.6, and connections to the appliance are checked for leakage. [NFPA 54:8.2.4]
1313.6 Purging Requirements. The purging of piping shall be in accordance with Section 1313.6.1 through Section 1313.6.3. [NFPA 54:8.3]
1313.6.1 Piping Systems Required to be Purged Outdoors. The purging of piping systems shall be in accordance with Section 1313.6.1.1 through Section 1313.6.1.4 where the piping system meets either of the following:
(1) The design operating gas pressure is greater than 2 psig (14 kPag).
(2) The piping being purged contains one or more sections of pipe or tubing meeting the size and length criteria of Table 1313.6.1. [NFPA 54:8.3.1]
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FUEL GAS PIPING
TABLE 1313.6.1
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
≥ 8Any length For SI units: 1 inch = 25 mm; 1 foot = 304.8 mm
***** CSST EHD size of 62 is equivalent to 2 inch (50 mm) nominal size pipe or tubing.
1313.6.1.1 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 1313.6.1.3. Where gas piping meeting the criteria of Table 1313.6.1 is removed from service, the residual fuel gas in the piping shall be displaced with an inert gas.
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 § 1211.7 High relevance — show source text
1211.7 Electrical Connections . . . . . . . . .229
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TABLE OF CONTENTS
1211.8 Earthquake-Actuated Gas Shutoff Valves . . . . . . . . . . . . . . . .229
1212.0 Appliance and Equipment Connections to Building Piping . . .229
1212.1 Connecting Appliances and Equipment . . . . . . . . . . . . . . . . . .229
1212.2 Suspended Low-Intensity Infrared Tube Heaters . . . . . . . . .230
1212.3 Use of Nonmetallic Gas
Hose Connectors . . . . . . . . . . . . .230
1212.4 Injection (Bunsen) Burners . . . . . .230
1212.5 Connection of Portable
and Mobile Industrial
Gas Appliances . . . . . . . . . . . . . .230
1212.6 Appliance Shutoff Valves and Connections . . . . . . . . . . . . . .230
1212.7 Quick-Disconnect Devices . . . . . .230
1212.8 Gas Convenience Outlets . . . . . .231
1212.9 Sediment Trap . . . . . . . . . . . . . . .231
1212.10 Installation of Piping . . . . . . . . . . .231
1212.11 Liquefied Petroleum Gas Facilities and Piping . . . . . . . . . . .231
1213.0 Pressure Testing, Inspection, and Purging . . . . . . . . . . . . . . . . .231
1213.1 Piping Installations . . . . . . . . . . . .231
1213.2 Test Preparation . . . . . . . . . . . . . .231
1213.3 Test Pressure . . . . . . . . . . . . . . . .232
1213.4 Detection of Leaks and Defects . .232
1213.5 Piping System Leak Test . . . . . . .232
1213.6 Purging Requirements . . . . . . . . .232
Table 1213.6.1 Size and Length of Piping . . . . . .232
1214.0 Required Gas Supply . . . . . . . . . .233
1214.1 General . . . . . . . . . . . . . . . . . . . . .233
1214.2 Volume . . . . . . . . . . . . . . . . . . . . .233
1214.3 Gas Appliances . . . . . . . . . . . . . .233
1214.4 Size of Piping Outlets . . . . . . . . . .233
1215.0 Required Gas Piping Size . . . . . .234
1215.1 Pipe Sizing Methods . . . . . . . . . . .234
1215.2 Sizing of Gas Piping Systems . . .234
1215.3 Sizing Equations . . . . . . . . . . . . . .234
Table 1215.3 Cr and Y for Natural Gas
CPC § 1313.6.1. High relevance — show source text
(2) The piping being purged contains one or more sections of pipe or tubing meeting the size and length criteria of Table 1313.6.1. [NFPA 54:8.3.1]
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FUEL GAS PIPING
TABLE 1313.6.1
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
≥ 8Any length For SI units: 1 inch = 25 mm; 1 foot = 304.8 mm
***** CSST EHD size of 62 is equivalent to 2 inch (50 mm) nominal size pipe or tubing.
1313.6.1.1 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 1313.6.1.3. Where gas piping meeting the criteria of Table 1313.6.1 is removed from service, the residual fuel gas in the piping shall be displaced with an inert gas.
[NFPA 54:8.3.1.1] 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]
CPC § 1201.0 High relevance — show source text
rials. Where contamination of system components has occurred, the affected component shall not be installed in the system.
F 1201.0 System Acceptance and Certification.
F 1201.1 Static Pressure Testing. Following fabrication, assembly, and installation of the piping distribution system, exterior connection panel, and interior cylinder fill panels, the Authority Having Jurisdiction shall witness the pneumatic testing of the complete system at a test pressure of not less than 7500 psi (51 711 kPa) using oil-free dry air, nitrogen, or argon. A pneumatic test of not less than 24 hours shall be performed. During this test, all fittings, joints, and system components shall be inspected for leaks. A solution compatible with the system component materials shall be used on each joint and fitting. Defects in the system or leaks detected shall be documented on an inspection report, repaired or replaced. As an alternate, a pressure-decay test in accordance with ASME B31.3 shall be permitted.
F 1201.2 Low-Pressure Switch Test. Upon successful completion of the 24-hour static pressure test, the system’s low-pressure monitoring switch shall be calibrated to not less than 3000 psi (20 684 kPa) descending, and tested to verify that the signal is annunciated at the building’s main fire alarm panel and by means of an audible alarm and visual strobe located in a visible location.
F 1201.3 Compatibility Check. Each air fill panel and station, and each exterior fire department connection panel shall be tested for compatibility with the fire department’s SCBA fill fittings.
F 1201.4 Material Certifications. The pipe or tubing material certifications shall be provided to the Authority Having Jurisdiction.
F 1201.5 Air Sampling. Before the system is placed into service, a minimum of two samples shall be taken from separate air fill panels and submitted to an independent certified gas analysis laboratory to verify the system’s cleanliness and that the air is in accordance with the following requirements for breathing air:
(1) Breathing air shall have oxygen content not less than 19.5 percent and not greater than 23.5 percent by vol ume.
(2) Breathing air shall not have a concentration of carbon monoxide exceeding 5.0 parts per million (ppm) by vol ume.
(3) Breathing air shall not have a concentration of carbon dioxide exceeding 1000 ppm by volume.
(4) Breathing air shall not have a concentration of condensed oil and particulate exceeding 7.2 E-11 pounds per cubic inch (lb/in [3] ) (2.0 mg/m [3] ) at 72 ° F (22 ° C) and 30 in Hg (102 kPa).
(5) Where breathing air supply for respirators is stored at pressures exceeding 15 bars (1500 kPa), the breathing air shall not have a concentration of water exceeding 24 ppm by volume.
(6) Breathing air shall not have a nonmethane volatile organic compound (VOC) content exceeding 25 ppm as methane equivalents.
(7) Breathing air shall not have a pronounced or unusual odor.
(8) Breathing air shall have a concentration of nitrogen not less than 75 percent and not more than 81 percent.
[NFPA 1989:5.6]
Frequently asked questions
When may appliances or equipment be placed into operation?
Appliances and equipment must not be placed into operation until the piping has been leak‑checked (immediately after gas is turned on), the piping has been purged where required, and appliance connections have been checked for leakage, per §1213.5.2–§1213.5.3.
Must purging be done outdoors?
Not always. Purging location depends on design pressure and pipe size/length: piping meeting Table 1213.6.1 or with design pressure > 2 psig must be purged outdoors with specified controls and monitoring; smaller or lower‑pressure systems may be purged indoors under approved procedures (see §1213.6.1 and §1213.6.2).
What happens if a leak is found during testing?
Any detected leakage or defect must be located, the affected portion repaired or replaced as required, and the piping retested before acceptance; minor repairs may be verified with an approved leak‑detecting fluid if permitted by the AHJ (see §1213.4.2 and §1213.1.2).
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- General Regulations
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- Water Heaters
- Water Supply and Distribution
- Sanitary Drainage (Drain, Waste, and Vent)
- Indirect Wastes
- Vents
- Traps and Interceptors
- Storm Drainage
- Fuel Gas Piping
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