CPC · California Plumbing Code
What are the CPC requirements for purging gas piping and outdoor discharge points?
If a gas line is purged to the open air, the CPC requires the discharge point be outdoors (or through an approved continuously‑ignited burner in limited cases), controlled by a shutoff valve, kept at least 10 feet from openings and 25 feet from air intakes, continuously attended and monitored with a listed numeric combustible‑gas indicator, and purging must stop when **90%** fuel gas is present in the pipe (see **§ 1213.6.1.4**, **§ 1213.6.1.5**, **§ 1213.6.2**, **§ 1213.6.2.1**).
Last reviewed: July 6, 2026
What the code requires — 2-4 sentences
When a gas piping system is purged or pressure‑vented to the open air, the open end must discharge to an outdoor location and meet specific location, monitoring, attendance, and shut‑off requirements described in § 1213.6.1.4. A listed, calibrated combustible gas indicator that displays 0–100% in 1% increments is required to monitor purging per § 1213.6.1.5. Piping meeting certain pressure and size/length criteria may be purged indoors only under the limited procedures of § 1213.6.2 and § 1213.6.2.1.
Always vent purged gas to the outdoors or through an approved continuously‑ignited burner, control the discharge with a valve, continuously monitor with a listed numeric combustible‑gas indicator, and stop when 90% fuel gas is detected. § 1213.6.1.4.
Requirements in detail
Outdoor discharge (what must be done at the open end)
- The discharge must go directly to an outdoor location. § 1213.6.1.4.
- The discharge point must be controlled by a shutoff valve. § 1213.6.1.4(1).
- The discharge must be attended at all times and monitored with a combustible gas indicator that meets § 1213.6.1.5. § 1213.6.1.4(3).
- Purging that introduces fuel gas must be stopped when 90 percent fuel gas by volume is detected in the pipe. § 1213.6.1.4(4).
Distance and occupant safety requirements
- Maintain at least 10 feet from sources of ignition and 10 feet from building openings. § 1213.6.1.4(2).
- Maintain at least 25 feet from mechanical air‑intake openings. § 1213.6.1.4(2).
- Evacuate persons not involved from all areas within 10 feet of the discharge point while purging. § 1213.6.1.4(5).
Monitoring device requirements
- The required combustible gas indicator must be listed, calibrated per manufacturer’s instructions, and numerically display 0–100% in 1% or smaller increments. § 1213.6.1.5.
When indoor purging is allowed
Pipes are permitted to be purged indoors or outdoors only where both conditions of § 1213.6.2 are met:
- Design operating pressure ≤ 2 psig (14 kPag), and
- The piping is constructed entirely of pipe/tubing that does not meet the size/length thresholds of Table 1213.6.1. § 1213.6.2.
If those conditions are met, the acceptable purging procedures in § 1213.6.2.1 include one or more of:
- Purge with fuel gas discharging to the outdoors; or
- Purge through an appliance burner (not in a combustion chamber) that has a continuous source of ignition; or
- Purge through a burner designed for purging with a continuous ignition source; or
- Purge with monitoring by a listed combustible gas detector and stop when fuel gas is detected; or
- Purging performed by the gas supplier under written procedures. § 1213.6.2.1(1)–(5).
Decision table — quick reference
| Decision factor | Required value / action | Code Reference |
|---|---|---|
| Discharge location | Outdoors (directly) unless using approved burners/monitoring per § 1213.6.2.1 | § 1213.6.1.4, § 1213.6.2.1 |
| Discharge distance to ignition or openings | ≥ 10 ft from ignition, ≥ 10 ft from building openings | § 1213.6.1.4(2) |
| Discharge distance to mechanical air intake | ≥ 25 ft | § 1213.6.1.4(2) |
| Attendance and monitoring | Continuous attendance; monitored with listed combustible gas indicator | § 1213.6.1.4(3), § 1213.6.1.5 |
| When to stop purging | When 90% fuel gas by volume is detected | § 1213.6.1.4(4) |
| Evacuation radius | Persons not involved evacuated from 10 ft around discharge | § 1213.6.1.4(5) |
| Indoor purging allowed when | Design pressure ≤ 2 psig (14 kPag) and piping small/short per Table 1213.6.1 | § 1213.6.2 |
| Combustible gas indicator specs | Listed, calibrated; numeric display 0–100% in 1% increments | § 1213.6.1.5 |
Exceptions & special cases
- Smaller/low‑pressure piping (design pressure ≤ 2 psig) and piping that does not meet Table 1213.6.1 size/length limits may be purged indoors provided they follow one of the specific procedures in § 1213.6.2.1, such as discharging through a continuously‑ignited burner or being purged by the gas supplier under written procedures. § 1213.6.2, § 1213.6.2.1.
- Purging through an appliance burner is permitted only if the burner is not located in a combustion chamber and has a continuous ignition source. § 1213.6.2.1(2).
- Where Table 1213.6.1 size/length thresholds are exceeded (see Table 1213.6.1 in CPC), outdoor purging procedures of § 1213.6.1.4 apply. See Table 1213.6.1 and § 1213.6.1 for applicability.
If you need to rely on an alternate means (for example, a remote discharge point with different clearances), that would need approval by the Authority Having Jurisdiction; the code does not provide alternative distances in these sections.
Common mistakes
- Leaving the discharge unattended or failing to use a listed numeric combustible gas indicator — the code requires continuous attendance and a numeric 0–100% display. § 1213.6.1.4(3), § 1213.6.1.5.
- Purging into or too near mechanical air intakes, building openings, or ignition sources — maintain 10 ft to ignition/building openings and 25 ft to intakes. § 1213.6.1.4(2).
- Not stopping at 90% fuel gas concentration (waiting for 100%): the code requires stopping at 90% fuel gas by volume. § 1213.6.1.4(4).
- Assuming indoor purging is always allowed — indoor purging is limited and only allowed when § 1213.6.2 criteria and the procedures of § 1213.6.2.1 are satisfied.
- Using an unlisted or improperly calibrated detector — indicators must be listed and calibrated per manufacturer instructions. § 1213.6.1.5.
Worked example — concrete scenario
Scenario: A contractor installs a new 3‑inch nominal gas main run of 40 feet to a commercial cookline. Table 1213.6.1 shows a 3" nominal pipe with length threshold > 30 ft triggers the outdoor purging requirement (Table 1213.6.1 — size/length criteria). Because the run is 40 ft, the contractor must follow the outdoor purging rules of § 1213.6.1.4: discharge directly outdoors, control the point of discharge with a shutoff valve, keep the discharge at least 10 ft from building openings and sources of ignition and 25 ft from mechanical air intakes, continuously attend the discharge and monitor with a listed combustible gas indicator that displays 0–100% in 1% increments, evacuate unauthorized persons within 10 ft, and stop purging when 90% fuel gas by volume is detected in the pipe. § 1213.6.1.4, § 1213.6.1.5, Table 1213.6.1.
Related provisions
- § 1213.6.1 — Piping systems required to be purged outdoors (applicability and Table 1213.6.1).
- § 1213.6.1.4 — Outdoor discharge of purged gases (detailed outdoor requirements).
- § 1213.6.1.5 — Combustible gas indicator specifications (listed, calibrated, numeric 0–100%).
- § 1213.6.2 — When piping may be purged indoors or outdoors (pressure and size/length criteria).
- § 1213.6.2.1 — Acceptable purging procedures when indoor purging is permitted (burners with continuous ignition, supplier procedures, listed detectors).
- Table 1213.6.1 — Size and length criteria referenced by §§ 1213.6.1 and 1213.6.2.
Code references
Grounded in the retrieved California Plumbing Code — click a citation to read the verbatim passage:
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.
232 2025 CALIFORNIA PLUMBING CODE
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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 § 8.3.1.3 High relevance — show source text
(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.
(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.
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 § 1313.6.2 High 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.
2025 CALIFORNIA MECHANICAL CODE 293
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FUEL GAS PIPING
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 § 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 § 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 § 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 § 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
CPC § 3308.1 Medium relevance — show source text
3308.1 Conditions of use. Internal-combustion-powered construction equipment shall be used in accordance with all of the following conditions:
- Equipment shall be located so that exhausts do not discharge against combustible material.
- Exhausts shall be piped to the outside of the building.
- Equipment shall not be refueled while in operation.
- Fuel for equipment shall be stored in an approved area outside of the building.
SECTION 3309—HAZARDOUS MATERIALS
3309.1 Storage of flammable and combustible liquids. Storage of flammable and combustible liquids shall be in accordance with Section 5704.
3309.1.1 Class I and Class II liquids. The storage, use and handling of flammable and combustible liquids at construction sites shall be in accordance with Section 5706.2. Ventilation shall be provided for operations involving the application of materials containing flammable solvents.
3309.1.2 Housekeeping. Flammable and combustible liquid storage areas shall be maintained clear of combustible vegetation and waste materials. Such storage areas shall not be used for the storage of combustible materials.
3309.1.3 Precautions against fire. Sources of ignition and smoking shall be prohibited in flammable and combustible liquid storage areas. Signs shall be posted in accordance with Section 310.
3309.1.4 Handling at point of final use. Class I and II liquids shall be kept in approved safety containers.
3309.1.5 Leakage and spills. Leaking vessels shall be immediately repaired or taken out of service and spills shall be cleaned up and disposed of properly.
3309.2 Storage and handling. The storage, use and handling of flammable gases shall comply with Chapter 58.
3309.2.1 Cleaning with flammable gas. Flammable gases shall not be used to clean or remove debris from piping open to the atmosphere.
3309.2.2 Pipe cleaning and purging. The cleaning and purging of flammable gas piping systems, including cleaning new or existing piping systems, purging piping systems into service and purging piping systems out of service, shall comply with NFPA 56.
Exceptions:
- Compressed gas piping systems other than fuel gas piping systems where in accordance with Chapter 53.
- Piping systems regulated by the International Fuel Gas Code .
- Liquefied petroleum gas systems in accordance with Chapter 61.
- Cleaning and purging of refrigerant piping systems shall comply with the California Mechanical Code .
3309.3 Storage and handling. Explosive materials shall be stored, used and handled in accordance with Chapter 56.
3309.3.1 Supervision. Blasting operations shall be conducted in accordance with Chapter 56.
3309.3.2 Demolition using explosives. Approved fire hoses for use by demolition personnel shall be maintained at the demolition site wherever explosives are used for demolition. Such fire hoses shall be connected to an approved water supply and shall be capable of being brought to bear on post-detonation fires anywhere on the site of the demolition operation.
SECTION 3310—ADDITIONAL SAFEGUARDS FOR OCCUPIED BUILDINGS
3310.1 Storage. Combustible materials associated with construction, demolition, remodeling or alterations to an occupied structure shall not be stored in exits, enclosures for stairways and ramps, or exit access corridors serving an occupant load of 30 or more.
Exceptions:
- Where the only occupants are construction workers.
CPC § 9.6.2 Medium relevance — show source text
(2) The connector shall be of minimum length and shall not exceed 6 feet (1829 mm).
(3) The connector shall not be concealed and shall not extend from one room to another or pass through wall partitions, ceilings, or floors. [NFPA 54:9.6.2(1)] 1212.3.2 Outdoor. Where outdoor gas hose connectors are used to connect portable outdoor appliances, the connector shall be listed in accordance with CSA/ANSI
Z21.54/CSA 8.4 and installed in accordance with the following:
(1) An appliance shutoff valve, a listed quick-disconnect device, or a listed gas convenience outlet shall be installed where the connector is attached to the supply piping and in such a manner so as to prevent the accumulation of water or foreign matter.
(2) This connection shall be made only in the outdoor area where the appliance is to be used. [NFPA 54:9.6.2(2)]
(3) The connector length shall not exceed 15 feet (4572 mm).
230 2025 CALIFORNIA PLUMBING CODE
), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.
FUEL GAS PIPING
1212.8 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]
1212.9 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 1212.9, 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 1212.9
METHOD OF INSTALLING A TEE FITTING SEDIMENT TRAP
[NFPA 54: FIGURE 9.6.8]
1212.10 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] 1212.11 Liquefied Petroleum Gas Facilities and Pip- ing. Liquefied petroleum gas facilities shall be in accordance with NFPA 58.
1213.0 Pressure Testing, Inspection, and Purging.
1213.1 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]
CPC § 701.3 Medium relevance — show source text
H 701.3, H 801.3
Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .218.0
Design . . . . . . . . . . . . . . . . .H 101.6, H 501.2, H 501.11,
H 901.4, H 901.7
Disposal systems . . . . . . . . . .218.0, 713.2, Appendix H General requirements . . . . . . . . . . . . . . . . . . . . .H 101.2 Inspections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .105.0
Location . . . . . . . . . . . . . . .721.0, H 101.8, Table H 101.8
PRIVATE WATER SUPPLY . . . . . . . . .602.2, 602.4, E 302.1
PROHIBITED
Appliances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .310.5 Concealed gas piping . . . . . . . . . . .1210.4.2, 1212.3.1,
1212.5.3, 1323.6
Concealment of defects . . . . . . . . . . . . . . . . . . . . .309.2
Concealment of work
before inspection . . . . . . . . . . . . . . . . . .105.0, 503.2,
1203.0, 1406.1
Connections
Sewer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .714.3
Waste . . . . . . . . . . . . . . . . . .310.3, 404.2, 603.4.4,
805.1, 807.3, 810.1
Water . . . . . . . . . . . . . . . . .602.0, 603.4.4, E 502.3
Copper tubing, use of . . . . . . . . . . .903.2.2, 1208.5.3.3 Damage to drainage system . . . . . .305.1, 312.3, 312.6
Devices . . . . . . . . . . . . . . . . . . . . . . . . . .310.5, 1210.10
Direct drainage . . . . . . . . . . . . . . . . . . . .603.4.4, 805.1,
807.3, 810.1
Discharge . . . . . . . . . . . . . . . .509.1.2, 714.2, 1603.3.2,
K 104.2
Fittings . . . . . . . . . . . . . . . . . . . . . . .310.0, 315.2, 604.2
Frequently asked questions
Can I purge a populated room or building interior?
You may only purge indoors when the piping meets both criteria of § 1213.6.2 (design pressure ≤ 2 psig (14 kPag) and not meeting Table 1213.6.1 size/length limits) and then only by one of the methods listed in § 1213.6.2.1 (for example, discharging through a continuously‑ignited burner or under gas‑supplier written procedures).
How close can the discharge be to an air intake or a window?
The open discharge must be at least 25 feet from mechanical air intakes and at least 10 feet from building openings (windows, doors) and sources of ignition as required by § 1213.6.1.4(2).
What kind of gas monitor do I need?
Use a listed, calibrated combustible gas indicator that numerically displays 0–100% in 1% increments per § 1213.6.1.5; the discharge point must be continuously monitored with that device during purging.
When do I stop purging?
Stop purging when 90 percent fuel gas by volume is detected within the pipe per § 1213.6.1.4(4).
Can the gas supplier perform the purge?
Yes — one allowed option in § 1213.6.2.1(5) is that the piping may be purged by the gas supplier in accordance with written procedures.
More in California Plumbing Code
- Administration
- Definitions
- General Regulations
- Plumbing Fixtures and Fixture Fittings
- Water Heaters
- Water Supply and Distribution
- Sanitary Drainage (Drain, Waste, and Vent)
- Indirect Wastes
- Vents
- Traps and Interceptors
- Storm Drainage
- Fuel Gas Piping
- Health Care Facilities — Medical Gas and Medical Vacuum Systems
- Alternate Water Sources and Nonpotable Rainwater Catchment Systems
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