CMC · California Mechanical Code
What are the pressure testing, purging and acceptable test‑media procedures?
Before you put gas piping into service you must visually inspect it, pressure‑test it using air/nitrogen/CO2/inert gas (not oxygen), and purge it by the methods the CMC requires. Outdoor purging is mandatory when system pressure exceeds 2 psig or when pipe size/length meets **Table 1313.6.1**; outdoor discharges must be shutoff‑valved, monitored with a listed combustible gas detector, located safely from openings and intakes, and stopped when **90%** fuel gas is reached.
Last reviewed: July 6, 2026
What the code requires — plain English
Before a gas piping installation is accepted or put into service the piping must be inspected and pressure‑tested, using an allowed test medium, and purged when required by size/length or pressure. The California Mechanical Code requires pressure tests (minimum pressures and minimum durations) and limits acceptable test media to air, nitrogen, carbon dioxide, or an inert gas — oxygen is prohibited; see § 1313.1 and § 1313.1.6 for these fundamentals.
The single most important practical rule: purge to outdoors when the system’s design pressure is greater than 2 psig or when the piping contains sections that meet Table 1313.6.1 size/length thresholds; discharge points must be monitored and located a safe distance from openings and ignitions.
Requirements in detail
What media are allowed for pressure testing
- The permitted test media are air, nitrogen, carbon dioxide, or another inert gas. Oxygen shall not be used for pressure testing. See § 1313.1.6.
Minimum test pressures & durations (general)
- For routine piping tests use an air, CO2, or nitrogen pressure test of not less than 10 psi (69 kPa) gauge held for a period acceptable to the Authority Having Jurisdiction but not less than 15 minutes. See § 1313.3.
- For welded piping or piping carrying gas at pressures above 14 in. water column (3.5 kPa), the test pressure must be not less than 60 psi (414 kPa) and held for not less than 30 minutes. For CSST at pressures > 14 in. wc the required test is 30 psi (207 kPa) for 30 minutes. See § 1313.3.
Leak detection, repair and re‑test
- The piping must withstand the specified test pressure without leakage. Leaks must be located by an approved gas detector, a non‑corrosive leak detection fluid, or other approved methods; repaired or replaced and the affected portion retested. See § 1313.4 and § 1313.4.1–.2.
Purging — when outdoors is required
Purging to outdoors is required when either:
- the design operating gas pressure is greater than 2 psig (14 kPag), OR
- the piping being purged contains one or more sections meeting the size and length criteria of Table 1313.6.1. See § 1313.6.1 and Table 1313.6.1.
Here is the Table from the code (decision‑relevant sizes/lengths):
| Nominal piping size (inches) | Length of piping (feet) that triggers outdoor purge | Code Reference |
|---|---|---|
| ≥ 2½ and < 3 | > 50 ft | Table 1313.6.1 / § 1313.6.1 |
| ≥ 3 and < 4 | > 30 ft | Table 1313.6.1 / § 1313.6.1 |
| ≥ 4 and < 6 | > 15 ft | Table 1313.6.1 / § 1313.6.1 |
| ≥ 6 and < 8 | > 10 ft | Table 1313.6.1 / § 1313.6.1 |
| ≥ 8 | Any length (always) | Table 1313.6.1 / § 1313.6.1 |
Purging — outdoor discharge controls and monitoring
If purging or pressure venting discharges to the outdoors the code requires all of the following in § 1313.6.1.3:
- The discharge point must be controlled with a shutoff valve.
- The discharge must be located at least 10 ft from sources of ignition and building openings, and 25 ft from mechanical air intakes.
- During discharge the open end must be continuously attended and monitored with a listed combustible gas indicator that displays 0–100% (1% increments).
- Stop introducing fuel gas into the purge when 90% fuel gas by volume is detected inside the pipe.
Purging — indoor or outdoor allowed cases and approved methods
Where the system meets both:
- operating pressure ≤ 2 psig (14 kPag) AND
- piping does not meet Table 1313.6.1 size/length thresholds, then purging may be done indoors or outdoors using approved methods per § 1313.6.2 (examples: purge to outdoors, purge through an appliance burner that has continuous ignition, or monitored purge with listed detector).
Test preparation, isolation, and safety
- Pipe joints must be exposed for inspection during test unless previously tested per the code; appliances/equipment not included in the test must be disconnected or isolated (blanks/caps) — § 1313.2 and subsections.
- If equipment connected to the test section is rated for less than the test pressure, the equipment must be disconnected or isolated before testing. See § 1313.2.4–.5.
- All testing must be performed to protect employees and the public — § 1313.2.6.
Exceptions & special cases
- Components or devices with a lower pressure rating than the pipe must be removed or isolated from the test section; if they cannot be removed or isolated the test pressure shall not exceed the component’s rating (this requirement is explicitly stated in related testing sections such as ground‑loop testing) — see the related test‑pressure guidance in § 1710.6.2.1 for how maximum test pressure is limited not to exceed component ratings.
- The code allows leak checks using actual fuel gas only after the piping has been pressure‑tested in accordance with the test sections; such fuel‑gas leak checks are permitted by § 1313.5.
- The code does not give additional specifics about utility‑installed devices such as excess flow valves (EFVs) or utility purging rules — those items are handled by the gas supplier or other agency standards and are not set out here; if you need EFV‑specific procedures check the gas supplier instructions (not contained in the retrieved CMC excerpts). (No CMC text for EFV procedures was found in the retrieved files.)
Common mistakes
- Using oxygen as the pressure test medium (forbidden) — code requires air, nitrogen, CO2, or inert gas only; see § 1313.1.6.
- Failing to isolate appliances or devices that are not pressure‑rated for the applied test pressure — see § 1313.2.3–.5.
- Purging to outdoors but placing the discharge point too close to building openings, mechanical intakes or ignition sources; the code requires distances of 10 ft and 25 ft where specified — see § 1313.6.1.3.
- Not continuously attending or monitoring the purge discharge with a listed combustible gas indicator (numeric 0–100%) as required by § 1313.6.1.4.
- Misreading Table thresholds: remember Table 1313.6.1 uses both nominal size and length to decide outdoor purge obligation — consult the table itself before deciding method.
Worked example — concrete scenario (numbers)
Scenario: New gas branch of 3‑inch nominal steel pipe, 40 ft long; system design pressure = 1 psig.
Does the system require outdoor purging?
- Table 1313.6.1 requires outdoor purge for nominal 3 in. piping when length is > 30 ft. The branch is 40 ft, so it meets the Table criteria — outdoor purge required even though operating pressure ≤ 2 psig. See Table 1313.6.1 and § 1313.6.1.
Purge procedure highlights:
- Arrange an outdoor discharge point controlled by a shutoff valve and located at least 10 ft from building openings and ignition sources, and 25 ft from mechanical air intakes. Continuously attend the discharge and monitor with a listed combustible gas indicator. Stop introducing fuel gas into the piping when the meter reads 90% fuel gas by volume inside the pipe. See § 1313.6.1.3 and § 1313.6.1.4.
Pressure testing before purging:
- Perform the required pressure test: for routine non‑welded piping the code requires a pressure of not less than 10 psi held for not less than 15 minutes (or as required by the AHJ). Use nitrogen or air — do not use oxygen. See § 1313.3 and § 1313.1.6.
Leak detection and placing in service:
- Locate any leaks with an approved detector or non‑corrosive leak detector solution, repair and retest per § 1313.4, then proceed with purging and final leak checks per § 1313.5.
Related provisions (CMC sections)
- § 1313.1 — Piping installations, inspection and pressure testing requirements.
- § 1313.1.6 — Acceptable test media (air, nitrogen, CO2, inert gas; oxygen prohibited).
- § 1313.2 — Test preparation, isolation of appliances and safety for testing.
- § 1313.3 — Required test pressures and minimum durations.
- § 1313.4 — Detection of leaks and required repair/retest.
- § 1313.5 — When fuel‑gas leak checks are permitted and turning gas on.
- § 1313.6.1 & Table 1313.6.1 — Criteria requiring outdoor purging and the size/length thresholds.
- § 1313.6.1.3 — Outdoor discharge controls, distances, monitoring, and the 90% stop criterion.
- § 1313.6.1.4 — Combustible gas indicator listing and numeric display requirements.
Code references
Grounded in the retrieved California Mechanical Code — click a citation to read the verbatim passage:
CMC § 1710.6.1 High relevance — show source text
1710.6.1 Backfill. Bentonite grout and thermallyenhanced bentonite grout, where used to seal and backfill each borehole, shall comply with NSF/ANSI/CAN 60. Boreholes shall be backfilled in accordance with the Authority Having Jurisdiction.
1710.6.2 U-Bends and Headers. Headers, u-bends and ground loop pipes shall be pressure-tested in accordance with ANSI/ CSA/IGSHPA C448, or as required by the Authority Having Jurisdiction. Before testing, heat fusion joints shall be cooled to ambient temperature. Mechanical joints shall be completely assembled. Flushing and purging to remove air and debris shall be completed before testing. The assembly shall be filled with water (or water/antifreeze solution) and purged at a minimum flow rate of 2 feet per second (0.6 m/s) to remove air, but not more than the maximum flow velocity recommended by the pipe and fittings manufacturer to remove debris.
1710.6.2.1 Test Pressure. The maximum test pressure shall be 1.5 times the system design pressure, as determined by Section 1710.6.2.3, or Section 1710.6.2.4, not to exceed 100 psi (689 kPa). Components or devices with lower pressure-ratings than the pipe shall be protected from excessive pressure during testing by removing or isolating from the test section.
Exception: Where lower pressure-rated components or devices cannot be removed or isolated from the test section, the maximum test pressure shall not exceed the pressure rating of the component or device.
1710.6.2.2 Testing Procedure. The test section and the test liquid shall be at the same temperature. The test section shall be filled with liquid and purged of air. The test section shall be brought to the specified test pressure. Test pressure shall be maintained for 4 hours, with additional fluid added as needed. The test pressure shall be reduced by 10 psi (69 kPa) and monitored for 1 hour with no addition of pres
sure or additional fluid. A passing test is indicated where after a period of 1 hour no visual leakage is observed, and pressure remains equal to or greater than 95 percent of the original pressure.
1710.6.2.3 Calculation of Static Pressure (Water). For water, the static pressure applied shall be equivalent to 0.43 psig (2.96 kPa) per foot (305 mm) of elevation.
1710.6.2.4 Calculation of Static Pressure (Other Fluids). For fluids of different density, the static pressure shall be calculated using the density of the system fluid.
1711.0 Ground-Heat Exchanger Testing.
1711.1 Testing. Pressure-testing of the ground-heat exchanger shall be performed in accordance with the testing method in Section 1710.6.
1711.2 Individual Loop Pressure Testing. Individual loop testing shall be performed as required by the Authority Having Jurisdiction.
1711.3 Field Pressure Testing – Final. The ground-heat exchanger and building piping shall be cleaned, flushed, and, where required, shall be filled with the heat transfer fluid medium. The ground loop system shall be tested at the design flow rate(s) and differential pressure(s) recorded. Where the actual pressure change at design flow is more than +/- 10 percent of the design flow pressure drop, the cause shall be identified, and corrective action taken.
CMC § 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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CMC § 1710.4 High relevance — show source text
1710.4 Underground Fittings. Underground fittings for closed-loop systems shall be in accordance with Section 1703.3 and Table 1703.3.
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GEOTHERMAL ENERGY SYSTEMS AND AMBIENT TEMPERATURE LOOPS
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1710.5 Verification. For closed-loop systems, the system shall be flushed of debris and purged of air after completion of the entire ground-heat exchanger. Flow rates and pressure drops shall be compared to calculated values to assure no blockage or kinking of the pipe. A report shall be submitted to the owner to confirm that the loop flow is in accordance with the construction documents.
1710.6 Vertical Bores. Vertical bores shall be drilled to a depth to provide complete insertion of the u-bend pipe to its specified depth. The borehole diameter shall be sized for the installation and placement of the heat exchange u-bend and the tremie used to place the grouting material. ANSI/ CSA/IGSHPA C448 shall be used for vertical loop depth and borehole diameter sizing guidance. The u-bend joint and pipe shall be visually inspected for integrity in accordance with the manufacturer’s installation instructions. The u-bend joint and pipe shall be pressurized to not less than 100 psi (689 kPa), not to exceed the pressure rating of the pipe at the test temperature, for 1 hour to check for leaks before insertion into the borehole.
1710.6.1 Backfill. Bentonite grout and thermallyenhanced bentonite grout, where used to seal and backfill each borehole, shall comply with NSF/ANSI/CAN 60. Boreholes shall be backfilled in accordance with the Authority Having Jurisdiction.
1710.6.2 U-Bends and Headers. Headers, u-bends and ground loop pipes shall be pressure-tested in accordance with ANSI/ CSA/IGSHPA C448, or as required by the Authority Having Jurisdiction. Before testing, heat fusion joints shall be cooled to ambient temperature. Mechanical joints shall be completely assembled. Flushing and purging to remove air and debris shall be completed before testing. The assembly shall be filled with water (or water/antifreeze solution) and purged at a minimum flow rate of 2 feet per second (0.6 m/s) to remove air, but not more than the maximum flow velocity recommended by the pipe and fittings manufacturer to remove debris.
1710.6.2.1 Test Pressure. The maximum test pressure shall be 1.5 times the system design pressure, as determined by Section 1710.6.2.3, or Section 1710.6.2.4, not to exceed 100 psi (689 kPa). Components or devices with lower pressure-ratings than the pipe shall be protected from excessive pressure during testing by removing or isolating from the test section.
Exception: Where lower pressure-rated components or devices cannot be removed or isolated from the test section, the maximum test pressure shall not exceed the pressure rating of the component or device.
CMC § 25.4 High relevance — show source text
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]
1313.1.3 New Branches. Where new branches are installed to new appliance(s), only 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] 1313.1.4 Piping System. 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 sys
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FUEL GAS PIPING
tem 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]
1313.1.5 Regulators and Valves. 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]
1313.1.6 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]
CMC § 1311.4 High relevance — show source text
1311.4 Prohibited Use . . . . . . . . . . . . . . . 289
1311.5 Lightning Protection System. . . . . 289
1311.6 Electrical Circuits . . . . . . . . . . . . . 289
1311.7 Electrical Connections . . . . . . . . . 289
1312.0 Appliance and Equipment Connections to Building Piping. . . 289
1312.1 Connecting Appliances and Equipment . . . . . . . . . . . . . . . . . . 289
2025 CALIFORNIA MECHANICAL CODE
1312.2 Suspended Low-Intensity Infrared Tube Heaters . . . . . . . . . 290
1312.3 Use of Nonmetallic Gas Hose
Connectors . . . . . . . . . . . . . . . . . . 290
1312.4 Injection (Bunsen) Burners . . . . . . 290
1312.5 Connection of Portable and
Mobile Industrial Appliances. . . . . 290
1312.6 Appliance Shutoff Valves and Connections. . . . . . . . . . . . . . 291
1312.7 Quick-Disconnect Devices . . . . . . 291
1312.8 Gas Convenience Outlets. . . . . . . 291
1312.9 Sediment Trap . . . . . . . . . . . . . . . 291
1312.10 Installation of Piping . . . . . . . . . . . 291
1312.11 Liquefied Petroleum Gas Facilities and Piping . . . . . . . . . . . 291
1313.0 Pressure Testing, Inspection, and Purging. . . . . . . . . . . . . . . . . . 291
1313.1 Piping Installations . . . . . . . . . . . . 291
1313.2 Test Preparation . . . . . . . . . . . . . . 292
1313.3 Test Pressure . . . . . . . . . . . . . . . . 292
1313.4 Detection of Leaks and Defects . . 292
1313.5 Piping System Leak Test . . . . . . . 292
1313.6 Purging Requirements . . . . . . . . . 292
Table 1313.6.1 Size and Length of Piping. . . . . . . 293
1314.0 Required Gas Supply . . . . . . . . . . 293
1314.1 General. . . . . . . . . . . . . . . . . . . . . 293
1314.2 Volume . . . . . . . . . . . . . . . . . . . . . 293
1314.3 Gas Appliances . . . . . . . . . . . . . . 294
1314.4 Size of Piping Outlets . . . . . . . . . . 294
1315.0 Required Gas Piping Size . . . . . . 294
1315.1 Pipe Sizing Methods. . . . . . . . . . . 294
1315.2 Sizing of Gas Piping Systems . . . 294
1315.3 Sizing Equations. . . . . . . . . . . . . . 294
Table 1315.3 Cr and Y for Natural Gas and
CMC § 1213.0 Medium relevance — show source text
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
and Undiluted Propane at Standard Conditions . . . . . . . . . . .234
1215.4 Sizing of Piping Sections . . . . . . .234
1215.5 Engineering Methods . . . . . . . . . .235
1215.6 Variable Gas Pressure . . . . . . . . .235
Table 1215.2(1) Schedule 40 Metallic Pipe . . . . . .237
Table 1215.2(2) Schedule 40 Metallic Pipe . . . . . .238
Table 1215.2(3) Schedule 40 Metallic Pipe . . . . . .239
Table 1215.2(4) Schedule 40 Metallic Pipe . . . . . .240
Table 1215.2(5) Schedule 40 Metallic Pipe . . . . . .241
Table 1215.2(6) Schedule 40 Metallic Pipe . . . . . .242
Table 1215.2(7) Semi-Rigid Copper Tubing . . . . . .243
Table 1215.2(8) Semi-Rigid Copper Tubing . . . . . .244
Table 1215.2(9) Semi-Rigid Copper Tubing . . . . . .245
Table 1215.2(10) Semi-Rigid Copper Tubing . . . . . .246
Table 1215.2(11) Semi-Rigid Copper Tubing . . . . . .247
Table 1215.2(12) Semi-Rigid Copper Tubing . . . . . .248
Table 1215.2(13) Semi-Rigid Copper Tubing . . . . . .249
Table 1215.2(14) Corrugated Stainless Steel Tubing (CSST) . . . . . . . . . . . . . . .250
California Mechanical Code Medium relevance — show source text
|100 psf|1 hr
23 min|||7|1, 2|11/3| |F/C-4-RC-9|4″|4″ deep (4370 psi);1/4″ reinforcement bars
at 6″ pitch with3/4″ cover;1/4″ main rein-
forcement bars at 4″ pitch perpendicular
with1/2″ cover; 13′1″ span restrained.|150 psf|2 hrs|||7|1, 3|2| |F/C-4-RC-10|4″|4″ thick (5140 psi) deck;1/4″ reinforce-
ment bars at 71/2″ pitch with7/8″ cover;3/8″
main reinforcement bars at 33/4″ pitch
perpendicular with1/2″ cover; 13′1″ span
restrained.|140 psf|1 hr
16 min|||7|1, 5|11/4| |F/C-4-RC-11|4″|4″ thick (4000 psi) concrete deck;
3″ × 11/2″ × 4 lbs R.S.J.; 2′6″ C.R.S.; flush
with top surface; 4″ × 6″ x 13 SWG mesh
reinforcement 1″ from bottom of slab; 6′6″
span restrained.|150 psf|2 hrs|||7|1, 3|2| |F/C-4-RC-12|4″|4″ deep (2380 psi) concrete deck;
3″ × 11/2″ × 4 lbs R.S.J.; 2′6″ C.R.S.; flush
with top surface; 4″ × 6″ x 13 SWG mesh
reinforcement 1″ from bottom surface;
6′6″ span restrained.|150 psf|1 hr
3 min|||7|1, 2|1| |F/C-4-RC-13|41/2″|41/2″ thick (5200 psi) deck;1/4″ reinforce-
ment bars at 71/4″ pitch with7/8″ cover;3/8″
main reinforcement bars at 33/4″ pitch
perpendicular with1/2″ cover; 13′1″ span
restrained.|140 psf|2 hrs|||7|1, 3|2| |F/C-4-RC-14|41/2″|41/2″ deep (2525 psi) concrete deck;1/4″
reinforcement bars at 71/2″ pitch with7/8″
cover;3/8″ main reinforcement bars at
33/8″ pitch perpendicular with1/2″ cover;
13′1″ span restrained.|150 psf|42 min|||7|1, 5|2/3| |F/C-4-RC-15|41/2″|41/2″ deep (4830 psi) concrete deck;
11/2″ × No.CMC § 1211.7 Medium 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
CMC § 1324.5.2.3 Medium 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]
CMC § 1310.8.3 Medium relevance — show source text
Change in direction . . . . . . . . . . . . . . . . . . . . . 1310.8.3
Concealed location . . . . . . . . . . . . . . . . . . . . . . . 1310.3
Detection of leaks . . . . . . . . . . . . . . . . . . . . . . . . 1313.4
Electrical bonding and grounding. . . . . . . . . . . . . 1311.0
Inspection and testing . . . . . . . . . . . . . . 1303.0, 1313.0
Installation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1310.0
Interconnections . . . . . . . . . . . . . . . . . . . . . . . . . 1308.2
Joints and fittings . . . . . . . . . . . . . . 1308.4.4–1308.4.8,
1313.2.1, 1313.2.2
Materials. . . . . . . . . . . . . . . . . . . . . . . . 1308.4, D 109.0
Obstruction of flow. . . . . . . . . . . . . . . . . . . . . . . 1310.12
Pressure regulators . . . . . . . . . . . . . . . . . . . . . . 1308.14
Purging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1313.6 Sizing . . . . . . . . . . . . . 1308.3, 1314.0, 1315.0, D 108.0, Table 1315.2(1)–Table 1315.2(36) Supports. . . . . . . . . . . . . . . . 1310.3.5, Table 1310.3.5.1
Underground
installations . . . . . . . . 1308.4.2.4, 1308.4.3.4, 1310.0,
D 101.2, D 109.3, D 110.3
Venting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1308.6.4
FUEL GAS TUBING
Cathodic protection . . . . . . . . . . . . . . . . . . . . . . D 105.0 Change in direction . . . . . . . . . . . . . . . . . . . . . 1310.8.3
Concealed location . . . . . . . . . . . . . . . . . . . . . . . 1310.4
Detection of leaks . . . . . . . . . . . . . . . . . . . . . . . . 1313.4
Electrical bonding and grounding. . . . . . . . . . . . . 1311.0 Inspection and testing . . . . . . . . . . . . . . 1303.0, 1313.0
CMC § 7.8. Medium relevance — show source text
D. For a branch service line, place a metal tag on the riser for each meter set. Extra metal tags may be purchased using material code M020957. Follow GDS A-42, “Standard Branch Service Installation,” for additional branch marking requirements.
7.8. Install EFVs on new stub service lines as close as possible to the gas main.
A. Leave the metal tag and adhesive sticker (if supplied) in the EFV plastic bag.
B. Wrap the bag around the buried stub.
C. Attach the metal tag on the riser and sticker (if supplied) to the pressure regulator when the service line is completed.
D. Ensure a properly sized EFV is present when performing a stub completion, if required.
Printed copies of this document might be out of date. The Technical Information Library (TIL) has the current version.
PG&E Internal Information “PG&E” refers to Pacific Gas and Electric Company, a subsidiary of PG&E Corporation.
©2021 Pacific Gas and Electric Company. All rights reserved.
Page 11 of 19
Excess Flow Valves A-93.3
Publication Date: 10/20/2021 Effective Date: 01/01/2022 Rev. 9c
7.9. Leak Testing
A. When leak-testing a service line that has an EFV, as required in GDS A-34, “Piping Test Design Requirements,” increase the air pressure slowly. A high flow may cause the EFV to trip. For example, take 15 seconds to pressurize a typical 50"–100" service line of ½" or 1" CTS.
B. Depressurize the service at a slow flow rate to avoid tripping the EFV.
7.10. Purging
A. Gas service lines with an EFV require a slower purge velocity than the normal gas purge procedure described in GDS A-38, “Purging Gas Facilities.”
B. Do not attempt to purge a gas main through a service that has an EFV.
C. Confirm there is an EFV identification tag on the gas service valve, service riser, riser sun shield, or pressure regulator. If the tag is present, an EFV has already been installed on the service.
D. Open the gas service valve very slowly and only partially.
- If the valve is fully opened, the resulting rapid flow of gas will activate andtrip the EFV.
- The EFV may activate when purging to atmosphere even if the gas valveis opened slowly.
- If the EFV activates during purging, shut off the gas service valve andwait until the pressure equalizes before attempting to continue purge.
E. When performing service work downstream of the regulator at the meter set, avoid removing a plug or associated piping too quickly because doing so can activate the EFV.
F. If the EFV activates, shut off the service valve and wait for the pressure to equalize. A typical EFV takes approximately 5 minutes to equalize.
8 Customer Notification
8.1. If a customer's service line operates at a pressure of 10 psig or greater throughout the year, PG&E must provide written or electronic notification to the customer of their right to request the installation of an EFV as specified in Code of Federal Regulations (CFR) Title 49, Transportation, Part 192—Transportation of Natural and Other Gas by Pipeline: Minimum Federal Safety Standards, Section (§) 192.383, "Excess flow valve installation."
CMC § 5.1.12.2.5.1 Medium relevance — show source text
[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]
1324.5.4.5 Conclusion of Test. The leakage over the 24-hour test shall not exceed 0.5 percent of the starting pressure [e.g., 0.3 psi (2 kPa) starting at 60 psig (414 kPa)] except that attributed to specific changes in ambient temperature. [NFPA 99:5.1.12.2.6.5]
1324.5.4.6 Leaks. Leaks, if any, shall be located, repaired (if permitted) or replaced (if required), and retested. [NFPA 99:5.1.12.2.6.6]
1324.5.4.7 Proof of Testing. The 24-hour standing pressure test of the positive pressure system shall be witnessed by an ASSE/IAPMO/ANSI 6020 inspector, an ASSE/IAPMO/ANSI 6030 verifier, or the Authority Having Jurisdiction or its designee. A form indicating that this test has been performed and witnessed shall be provided to the verifier at the start of the tests required in Section 1324.5.7 through Section 1324.5.11. [NFPA 99:5.1.12.2.6.7]
1324.5.5 Standing Pressure Tests – Medical Vac- uum Piping Systems. After successful completion of the initial pressure tests under Section 1324.5 through Section 1324.5.1.2, vacuum distribution piping shall be subjected to a standing vacuum test. [NFPA 99:5.1.12.2.7]
1324.5.5.1 Timeframe for Testing. Tests shall be conducted after installation of all components of the vacuum system. [NFPA 99:5.1.12.2.7.1]
CMC § 1313.1.6 High relevance — show source text
1313.1.6 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]
1313.2 Test Preparation. Test preparation shall comply with Section 1313.2.1 through Section 1313.2.6.
1313.2.1 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]
1313.2.2 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]
1313.2.3 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] 1313.2.4 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]
1313.2.5 Designed for Operating Pressures Equal to or Greater than Test Pressure. 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] 1313.2.6 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]
1313.3 Test Pressure. 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 (3.5 kPa) pressure, 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 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.
CMC § 318.0. Medium 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
CMC § 1201.0 Medium 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]
CMC § 8.3.1.1 Medium 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.
CMC § 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
2025 CALIFORNIA PLUMBING CODE 231
), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.
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
Can I use oxygen for pressure testing?
No. The code explicitly forbids oxygen as a test medium. Use air, nitrogen, carbon dioxide, or an inert gas as described in § 1313.1.6.
When must I purge to outdoors rather than indoors?
Purge outdoors when the design operating pressure is greater than 2 psig (14 kPag) or when any piping section meets the size and length thresholds in Table 1313.6.1. See § 1313.6.1 and Table 1313.6.1.
How close can the purge discharge be to a building opening?
The discharge must be at least 10 ft from building openings and ignition sources, and 25 ft from mechanical air intake openings; also the discharge must be continuously attended and monitored. See § 1313.6.1.3.
What instrument must I use to monitor a purge?
Use a listed combustible gas indicator that is calibrated and displays 0–100% in 1% increments; purging with fuel gas must stop when the pipe measures 90% fuel gas by volume. See § 1313.6.1.4 and § 1313.6.1.3(4).
How long must a pressure test be held?
Hold the routine pressure test at not less than 10 psi for not less than 15 minutes (or longer if the AHJ requires). For welded or higher‑pressure systems use 60 psi for not less than 30 minutes; CSST over 14 in. wc uses 30 psi for 30 minutes. See § 1313.3.
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