CPC · California Plumbing Code
Placing Piping in Operation and Removal
Before any gas piping or appliance is put into service in California, the piping must be leak‑checked and purged in the order required by the CPC: air displaced with inert gas, then inert displaced with fuel gas, with outdoor discharge, monitoring, and safety distances required whenever the line pressure is over 2 psig or the pipe size/length meets Table 1213.6.1.
Last reviewed: July 6, 2026
What the code requires
The California Plumbing Code requires that gas piping be properly purged and leak‑checked before appliances are put into service and that piping opened or removed from service be isolated and purged of residual fuel gas. Key rules are in § 1213.5 (leak checks and placing appliances in operation) and the purging and removal provisions in § 1213.6 and its subsections § 1213.6.1 – § 1213.6.3.
Always isolate any opened gas line, vent or displace the gas as required, and purge/monitor according to the size, length and pressure triggers in Table 1213.6.1 before placing piping or appliances into operation.
Quick summary (plain English)
- Before turning gas on: do a leak check (§ 1213.5.2) and do not operate appliances until the system is leak‑free and purged as required (§ 1213.5.3).
- If piping meets the size/length thresholds in Table 1213.6.1 or the design operating pressure is greater than 2 psig, purging/discharge must be done to the outdoors with monitoring and safety distances (§ 1213.6.1 & § 1213.6.1.4).
- If piping is to be removed or a section opened, isolate from gas and displace residual fuel gas with an inert gas before cutting/welding or abandonment (§ 1213.6.1.1–§ 1213.6.1.2).
Requirements in detail
1) When outdoor purging is mandatory
Two independent triggers require outdoor purging under § 1213.6.1 (purging requirements):
- Design operating gas pressure > 2 psig, or
- The piping contains one or more sections that meet the size and length criteria in Table 1213.6.1.
Refer to Table 1213.6.1 for exact nominal size vs. length thresholds.
2) Placing piping in operation (the sequence)
Where piping contains air and meets the outdoor‑purge criteria, the required sequence is:
- Displace the air with an inert gas (e.g., nitrogen). § 1213.6.1.3.
- Displace the inert gas with fuel gas in accordance with the outdoor discharge and monitoring rules in § 1213.6.1.4 and stop when 90% fuel gas by volume is detected in the pipe.
3) Removal from service and removal of piping
- § 1213.6.1.1 Removal from Service: When existing gas piping is opened, isolate the opened section from the gas supply and vent the line pressure per § 1213.6.1.4. If the piping meets Table 1213.6.1 criteria and is removed from service, residual fuel gas shall be displaced with an inert gas.
- § 1213.6.1.2 Removal of Piping: Before cutting or welding piping that contains gas, disconnect from gas sources and thoroughly purge with air, water, or inert gas.
4) Outdoor discharge — controls and monitoring
When discharging purged gases outdoors the code requires (see § 1213.6.1.4):
- A shutoff valve controlling the discharge point.
- Discharge location at least 10 feet from sources of ignition and building openings, and at least 25 feet from mechanical air intake openings.
- Continuous attendance and monitoring of the open discharge with a combustible gas indicator meeting § 1213.6.1.5 (numerical 0–100% display in 1% increments).
- Stop purging when 90% fuel gas by volume is reached; evacuate persons not involved within 10 feet.
5) When indoor purging is allowed (exceptions)
If both these conditions are true, indoor purging (or other controlled procedures) is permitted per § 1213.6.2:
- Design operating pressure ≤ 2 psig, and
- Piping is constructed entirely from pipe/tubing that does not meet the size/length criteria of Table 1213.6.1. When allowed, the code lists acceptable purging procedures (outdoor discharge, discharge through a continuously‑lit burner, monitored discharge with listed detector, or gas‑supplier purging under written procedures).
6) Leak checks and placing appliances into operation
- § 1213.5.2 Leak Check: Immediately after turning gas on to a new system or restoring service the system shall be checked for leaks; stop and repair if leakage is detected.
- § 1213.5.3 Placing Appliances and Equipment in Operation: Appliances must not be operated until the piping has passed leak check and been purged per § 1213.6 and connections checked for leakage.
Decision‑relevant values (quick reference table)
| Dimension / Value | When it matters | Code Reference |
|---|---|---|
| Design operating pressure > 2 psig | Triggers mandatory outdoor purge | § 1213.6.1 |
| Table 1213.6.1 size/length thresholds (see rows below) | Any piping section meeting these sizes/lengths requires outdoor purge | Table 1213.6.1 / § 1213.6.1 |
| Nominal ≥ 2½ in and < 3 in — length > 50 ft | Size/length trigger example | Table 1213.6.1 |
| Nominal ≥ 3 in and < 4 in — length > 30 ft | Size/length trigger example | Table 1213.6.1 |
| Nominal ≥ 4 in and < 6 in — length > 15 ft | Size/length trigger example | Table 1213.6.1 |
| Nominal ≥ 6 in and < 8 in — length > 10 ft | Size/length trigger example | Table 1213.6.1 |
| Nominal ≥ 8 in — any length | Any length triggers outdoor purge | Table 1213.6.1 |
| 10 ft / 25 ft | Discharge location: 10 ft from ignition/building openings; 25 ft from mechanical air intakes | § 1213.6.1.4 |
| 90% fuel gas by volume | Stop purging when this concentration is reached | § 1213.6.1.4 |
| Combustible gas indicator 0–100% display | Required for monitoring discharge; must be listed/calibrated | § 1213.6.1.5 |
| Evacuate people within 10 ft | Safety during outdoor discharge | § 1213.6.1.4 |
| Design operating pressure ≤ 2 psig + not meeting Table | Conditions that permit indoor purging (see allowed procedures) | § 1213.6.2 |
Exceptions & special cases
- Indoor purging is allowed when the piping’s design operating pressure is ≤ 2 psig and the piping is entirely composed of sizes/lengths that do not meet Table 1213.6.1 — see § 1213.6.2 for accepted procedures (discharge through a continuously lit burner with continuous ignition, monitored discharge with a listed detector, or gas‑supplier purging under written procedures).
- For smaller systems or low‑pressure lines that fail the Table criteria, purging to an appliance burner or using a gas supplier’s written procedure may be accepted under § 1213.6.2.1.
- The code requires inert‑gas displacement when removing piping that meets Table 1213.6.1 — § 1213.6.1.1. For removal or cutting/welding, purging with air, water, or inert gas is specified in § 1213.6.1.2.
If a code excerpt you need (for example, a specific administrative or local amendment) does not appear above in the cited CPC excerpts, I do not have that text in the retrieved files — do not assume additional exceptions beyond those shown in § 1213.6.1 – § 1213.6.3.
Common mistakes
- Failing to isolate and vent an opened section before working on it (violates § 1213.6.1.1).
- Cutting or welding a gas line without first disconnecting and purging (violates § 1213.6.1.2).
- Assuming indoor purging is allowed simply because a line is “small” — the code requires checking both the pressure (≤ 2 psig) and the Table 1213.6.1 size/length criteria (§ 1213.6.2).
- Discharging purge gas too close to openings, ignition sources, or intakes (ignore the 10 ft / 25 ft distances in § 1213.6.1.4).
- Not using or not calibrating a combustible gas indicator with a 0–100% numeric display while attending a discharge (§ 1213.6.1.5).
- Placing appliances into operation without performing the required leak check and purge (§ 1213.5.2 and § 1213.5.3).
Worked example
Scenario: You are placing into operation a newly installed 3‑inch nominal gas branch that is 40 feet long and currently contains air.
- Identify triggers: Table 1213.6.1 lists ≥ 3 in and < 4 in — length > 30 ft as a trigger, so this piping meets the size/length criteria and requires outdoor purging under § 1213.6.1. (3 in, 40 ft → outdoor purge required).
- Sequence to follow: Per § 1213.6.1.3, first displace the air with an inert gas (nitrogen). Then displace the inert gas with fuel gas, discharging to an outdoor location in compliance with § 1213.6.1.4.
- Safety/monitoring: Locate the discharge at least 10 ft from building openings and ignition sources and 25 ft from mechanical air intakes; control the discharge with a shutoff valve; continuously attend the open discharge and monitor with a listed, calibrated combustible‑gas indicator that reads 0–100% in 1% increments; stop purging when 90% fuel gas is detected in the line. Evacuate unrelated personnel within 10 ft while purging. (All per § 1213.6.1.4 & § 1213.6.1.5).
- After purge: Perform a leak check immediately after turning gas on in accordance with § 1213.5.2, then only place appliances into operation after the leak check and purge are complete per § 1213.5.3.
Related provisions
- § 1213.5.2 — Leak Check (immediate post‑turn‑on leak testing).
- § 1213.5.3 — Placing Appliances and Equipment in Operation (appliances only after leak check & purge).
- § 1213.6.1.1 — Removal from Service (isolate opened sections; inert displacement for removed piping).
- § 1213.6.1.2 — Removal of Piping (disconnect then purge with air, water or inert gas before cutting/welding).
- § 1213.6.1.3 — Placing in Operation (air → inert gas → fuel gas sequencing).
- § 1213.6.1.4 — Outdoor Discharge of Purged Gases (distances, shutoff valve, monitoring, 90% stop, evacuation).
- § 1213.6.1.5 — Combustible Gas Indicator requirements.
- § 1213.6.2 — Piping Systems Allowed to be Purged Indoors or Outdoors (conditions and procedures).
Code references
Grounded in the retrieved California Plumbing Code — click a citation to read the verbatim passage:
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 § 1213.5.2 High relevance — show source text
1213.5.2 Leak Check. Immediately after the gas is turned on into a new system or into a system that has been initially restored after an interruption of service, the piping system shall be checked for leakage. Where leak
age is indicated, the gas supply shall be shut off until the necessary repairs have been made. [NFPA 54:8.2.3]
1213.5.3 Placing Appliances and Equipment in Operation. Appliances and equipment shall not be placed in operation until after the piping system has been checked for leakage in accordance with Section 1213.5.2, the piping system is purged in accordance with Section 1213.6, and connections to the appliance are checked for leakage. [NFPA 54:8.2.4]
1213.6 Purging Requirements. The purging of piping shall be in accordance with Section 1213.6.1 through Section 1213.6.3. [NFPA 54:8.3]
1213.6.1 Piping Systems Required to be Purged Outdoors. The purging of piping systems shall be in accordance with Section 1213.6.1.1 through Section 1213.6.1.5 where the piping system meets either of the following:
(1) The design operating gas pressure is greater than 2 psig (14 kPa).
(2) The piping being purged contains one or more sections of pipe or tubing meeting the size and length criteria of Table 1213.6.1. [NFPA 54:8.3.1]
TABLE 1213.6.1
SIZE AND LENGTH OF PIPING
[NFPA 54: TABLE 8.3.1]*
NOMINAL PIPING SIZE
(inches)LENGTH OF PIPING
(feet)
≥ 21⁄2 < 3> 50
≥ 3 < 4> 30
≥ 4 < 6> 15
≥ 6 < 8> 10
≥ 8Any length For SI units: 1 inch = 25 mm, 1 foot = 304.8 mm
- CSST EHD size of 62 is equivalent to nominal 2 inches (50 mm) pipe or tubing size.
1213.6.1.1 Removal from Service. Where existing gas piping is opened, the section that is opened shall be isolated from the gas supply and the line pressure vented in accordance with Section 1213.6.1.4. Where gas piping meeting the criteria of Table 1213.6.1 is removed from service, the residual fuel gas in the piping shall be displaced with an inert gas. [NFPA 54:8.3.1.1]
1213.6.1.2 Removal of Piping. Where piping containing gas is to be removed, the line shall be first disconnected from sources of gas and then thoroughly purged with air, water, or inert gas before cutting, or welding is done.
1213.6.1.3 Placing in Operation. Where gas piping containing air and meeting the criteria of Table
TABLE 1213.6.1
SIZE AND LENGTH OF PIPING
CPC § 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 § 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 § 3109F.1 High relevance — show source text
MARINE OIL TERMINALS
Division 9
SECTION 3109F — PIPING AND PIPELINES
3109F.1 General. This section provides minimum engineering standards for piping, pipelines, valves, supports and related appurte- nances at MOTs. This section applies to piping and pipelines used for transferring: 1. Oil (see Section 3101F.1) to or from tank vessels or barges
2. Oil within the MOT
3. Vapors, including Volatile Organic Compounds (VOCs) 4. Inerting or enriching gases to vapor control systems
Additionally, it also applies to piping or pipelines providing services, which includes stripping, sampling, venting, vapor control and fire water.
See Section 3101F.3 for definitions of “new” (N) and “existing” (E).
3109F.2 Oil piping and pipeline systems. All pressure piping and pipelines for oil service shall conform to the provisions of API Standard 2610 [9.1], ASME B31.3 [9.2] or B31.4 [9.3] as appropriate, including the following: 1. All piping/pipelines shall be documented on current P&IDs (N/E). 2. Piping and pipeline systems shall be installed above deck (N). 3. The systems shall be arranged in a way not to obstruct access to and removal of other piping components and equipment (N). 4. Flexibility shall be achieved through adequate expansion loops or joints (N/E). 5. A guide or lateral restraint shall be provided just past the elbow where a pipe changes direction in order to minimize excessive axial stress (N). 6. Piping shall be routed to allow for movement due to thermal expansion and seismic displacement, without exceeding the allowable stresses in the supports, and anchor connections (see Section 3109F.3) (N/E). 7. Plastic piping shall not be used unless designated for oil service (N/E). 8. If a flanged connection exists within 20 pipe diameters from the end of any replaced section, the pipe shall be replaced up to and including the flange. 9. Pipelines shall be seamless, electric-resistance-welded or electric-fusion-welded (N). 10. Piping greater than 2 inches in diameter shall be butt-welded. Piping 2 inches and smaller shall be socket welded or threaded. 11. Pipeline connections directly over the water shall be welded (N). Flanged connections not over water shall have secondary containment (N). 12. Pipelines that do not have a valid and certified Static Liquid Pressure Test (SLPT) [9.4] shall be marked “OUT OF SERVICE.” Out- of-service piping and pipelines shall be purged, gas-freed and physically isolated from sources of oil. 13. If a pipeline is “out-of-service” for 3 or more years, it will require a valid and certified Static Liquid Pressure Test (SLPT) and API 570 inspection [9.4] prior to Division approval for re-use (E). 14. New piping and pipeline systems require a valid and certified Static Liquid Pressure Test (SLPT) [9.4] and Division approval, prior to operation.
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 § 9.1 Medium relevance — show source text
2. Conform to Section 10 of API Standard 2610 [9.1] (N/E). 3. Stems shall be oriented in a way not to pose a hazard in operation or maintenance (N/E). 4. Nonductile iron, cast iron and low-melting temperature metals shall not be used in any hydrocarbon service (N/E). 5. Double-block and bleed valves shall be used for manifold valves (N/E).
6. Isolation valves shall be fire-safe in accordance with API Standard 607 [9.10] (N). 7. Swing check valves shall not be installed in vertical down-flow piping (N/E). 8. Pressure relief devices shall be used in any closed piping system that has the possibility of being over pressurized due to temperature increase (thermal relief valves) (N/E). 9. Pressure relief devices shall be used in any piping system that has the possibility of being over pressurized due to surging, considering all plausible normal and abnormal operational scenarios in accordance with ASME B31.4 [9.3] (N/E). 10. Pressure relief devices shall be sized in accordance with API RP 520 [9.11] (N). Set pressures and accumulating pressures shall be in accordance with API RP 520 [9.11] (N/E). 11. Discharge from pressure relief valves shall be directed into lower pressure piping for recycling or proper disposal. Discharge shall never be directed into the open environment, unless secondary containment is provided (N/E). 12. Threaded, socket-welded, flanged and welded fittings shall conform to Section 8 of API Standard 2610 [9.1] (N/E). 13. ESD valves and SIVs shall also conform to the requirements of Sections 3108F.3.2.1 and 3108F.3.2.2.
3109F.5.2 Valve actuators (N/E).
1. Actuators shall have a readily accessible, manually operated overriding device to operate the valve during a power loss. 2. Torque switches shall be set to stop the motor closing operation at a specified torque setting. 3. Limit switches shall be set to stop the motor opening operation at a specified limit switch setting. 4. Critical valves shall be provided with thermal insulation. The insulation shall be inspected and maintained at periodic inter- vals. Records of thermal insulation inspections and condition shall be maintained for at least 6 years. 5. Electrical insulation for critical valves shall be measured for resistance following installation and retested periodically. These records shall be maintained for at least 6 years. 6. ESD valve and SIV actuators shall also conform to the requirements of Section 3108F.3.2.
3109F.6 Utility and auxiliary piping and pipeline systems. Utility and auxiliary piping includes service for: 1. Stripping and sampling 2. Vapor control 3. Natural gas 4. Compressed air, venting and nitrogen
Stripping and sampling piping shall conform to Section 3109F.2 (N/E).
Vapor return lines and VOC vapor inerting and enriching (natural gas) piping shall conform to 33 CFR 154.2100(b) [9.12] (N/E).
Compressed air, venting and nitrogen piping and fittings shall conform to ASME B31.3 [9.2] (N).
CPC § 8.3.2.1 Medium relevance — show source text
(5) The piping shall be purged by the gas supplier in accordance with written procedures. [NFPA 54:8.3.2.1] 1313.6.2.2 Combustible Gas Detector. Combustible gas detectors shall be listed and calibrated or tested in accordance with the manufacturer’s instructions. Combustible gas detectors shall be capable of indicating the presence of fuel gas. [NFPA 54:8.3.2.2] 1313.6.3 Purging Appliances and Equipment. After the piping system has been placed in operation, appliances and equipment shall be purged before being placed into operation. [NFPA 54:8.3.3]
1314.0 Required Gas Supply. 1314.1 General. The following regulations, shall comply with this section and Section 1315.0, shall be the standard for the installation of gas piping. Natural gas regulations and tables are based on the use of gas having a specific gravity of 0.60 and for undiluted liquefied petroleum gas having a specific gravity of 1.50. Where gas of a different specific gravity is to be delivered, the serving gas supplier shall be permitted to be contacted for specific gravity conversion factors to use in sizing piping systems from the pipe sizing tables in this chapter. 1314.2 Volume. The hourly volume of gas required at each piping outlet shall be taken as not less than the maximum hourly rating as specified by the manufacturer of the appliance or appliances to be connected to each such outlet.
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FUEL GAS PIPING
1314.3 Gas Appliances. Where the gas appliances to be installed have not been definitely specified, Table 1308.3.1 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. 1314.4 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 (15 mm). The size of a piping outlet for a mobile home shall be not less than [3] ⁄ 4 of an inch (20 mm).
CPC § 1303.3.3.1 Medium relevance — show source text
Necessary apparatus for conducting tests shall be furnished by the permit holder. Test gauges used in conducting test shall be in accordance with Section 1303.3.3.1 through Section 1303.3.3.4. 1313.4 Detection of Leaks and Defects. The piping system shall withstand the test pressure specified without showing any evidence of leakage or other defects. Any reduction of test pressures as indicated by pressure gauges shall be deemed to indicate the presence of a leak unless such reduction can be readily attributed to some other cause. [NFPA 54:8.1.5.1] 1313.4.1 Detecting Leaks. The leakage shall be located by means of an approved gas detector, a noncorrosive leak detection fluid, or other approved leak detection methods. [NFPA 54:8.1.5.2] 1313.4.2 Repair or Replace. Where leakage or other defects are located, the affected portion of the piping system shall be repaired or replaced and retested. [NFPA 54:8.1.5.3] 1313.5 Piping System Leak Test. Leak checks using fuel gas shall be permitted in piping systems that have been pressure-tested in accordance with Section 1313.0 through Section 1313.4.2. [NFPA 54:8.2.1] 1313.5.1 Turning Gas On. During the process of turning gas on into a system of new gas piping, the entire system shall be inspected to determine that there are no open fittings or ends and that all valves at unused outlets are closed and plugged or capped. [NFPA 54:8.2.2] 1313.5.2 Leak Check. Immediately after the gas is turned on into a new system or into a system that has been initially restored after an interruption of service, the piping system shall be checked for leakage. Where leakage is indicated, the gas supply shall be shut off until the necessary repairs have been made. [NFPA 54:8.2.3]
1313.5.3 Placing Appliances and Equipment in Operation. Appliances and equipment shall not be placed in operation until after the piping system has been checked for leakage in accordance with Section 1313.5.2, the piping system is purged in accordance with Section 1313.6, and connections to the appliance are checked for leakage. [NFPA 54:8.2.4]
1313.6 Purging Requirements. The purging of piping shall be in accordance with Section 1313.6.1 through Section 1313.6.3. [NFPA 54:8.3]
1313.6.1 Piping Systems Required to be Purged Outdoors. The purging of piping systems shall be in accordance with Section 1313.6.1.1 through Section 1313.6.1.4 where the piping system meets either of the following:
(1) The design operating gas pressure is greater than 2 psig (14 kPag).
(2) The piping being purged contains one or more sections of pipe or tubing meeting the size and length criteria of Table 1313.6.1. [NFPA 54:8.3.1]
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CPC § 304.8 Medium relevance — show source text
–|––|30|80|350| |10|5600|––|––|––|––|––|––|25|60|250|
For SI units: 1 inch = 25 mm, 1 foot = 304.8 mm
C 501.2 System Design. Vacuum waste drainage systems shall be designed and installed in accordance with the manufacturer’s installation instructions. A vacuum waste drainage system shall include a vacuum generating system, waste collection center, piping network, vacuum valve, and control components used to isolate the vacuum piping network from atmospheric pressure and to collect waste at its point of origin. Where a vacuum system provides the only means of sanitation, the duplicate vacuum generating equipment set to operate automatically shall be installed to allow the system to continue in operation during periods of maintenance. C 501.2.1 Vacuum Generating System. The vacuum generating station shall include vacuum pumps to create a constant vacuum pressure within the piping network and storage tanks. The operation of pumps, collection tanks, and alarms shall be automated by controls. The vacuum pumps shall be activated on demand and accessible for repair or replacement. The vent from the vacuum pump shall be provided for vacuum pump air exhaust and shall be of a size capable of handling the total air volume of the vacuum pump.
C 501.2.2 Waste Collection Center or Storage Tanks. Vacuum collection center or storage tanks shall
be of such capacity as to provide storage of waste to prevent fouling of the system. Such collection or storage tank shall be capable of withstanding 150 percent of the rated vacuum (negative pressure) created by the vacuum source without leakage or collapse. Waste collection center or storage tanks shall be accessible for adjustment, repair, or replacement.
C 501.2.3 Piping Network. The piping network shall be under a continuous vacuum and shall be designed to withstand 150 percent of the vacuum (negative pressure) created by the vacuum source within the system without leakage or collapse. Sizing the piping network shall be in accordance with the manufacturer’s instructions. The water closet outlet fitting shall connect with a piping network having not less than an 1 [1] ⁄ 2 inch (40 mm) nominal inside diameter.
C 501.2.4 Vacuum Interface Valve. A closed vacuum interface valve shall be installed to separate the piping network vacuum from atmospheric pressure. A control device shall open the vacuum interface valve where a signal is generated to remove waste from the plumbing fixture. C 501.2.5 Control Components. Where a pneumatic signal is generated at the controller, a vacuum from the
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APPENDIX C
system to open the extraction valve shall be designed to operate where vacuum pressure exists to remove the accumulated waste. Each tank shall incorporate a level indicator switch that automatically controls the discharge pump and warns of malfunction or blockage as follows:
(1) Start discharge.
(2) Stop discharge.
(3) Activate an audible alarm where the level of effluent is usually high.
(4) Warning of system shutdown where the tank is full.
C 501.3 Fixtures. Fixtures utilized in a vacuum waste drainage system shall be in accordance with referenced standards listed in Chapter 17. Components shall be of corrosion resistant materials.
CPC § 614.2 Medium relevance — show source text
Branch lines may be PFA (perfluoroalkoxy)._ 614.2 All piping for multistation or central dialysis units shall be rigid where possible. All piping and tubing shall be in a neat arrangement. The placement of piping or tubing on the floor is not permitted.
614.3 All valves shall be located in accessible locations.
614.4 Piping and valves shall be identified according to their function. 614.5 A means of preventing backwashing or flushing of the system when one or more stations are in operation shall be pro- vided.
614.6 A continuous audible alarm shall sound at the nurses’ station and remote equipment rooms when the minimum veloc- ity is not maintained, or if backwashing or flushing is attempted while one or more stations are in operation. 614.7 Water treatment equipment and water used for dialysis treatment shall meet the latest edition of American Association of Medical Instrumentations (AAMI)/ISO ANSI/AAMI/ISO 23500-2 and 23500-3, Preparation And Quality Management Of Fluids For Haemodialysis And Related Therapies—Part 2: Water Treatment Equipment for Hemodialysis Applications And Related Therapies and Part 3: Water For Haemodialysis And Related Therapies.
614.8 A diagram of all piping as installed shall be posted at the nurses’ station and equipment room of all multistation or cen- tral dialysis units.
615.0 Identification of Potable and Nonpotable Water Lines.
615.1 Uses Not Permitted.
615.1.1 [OSHPD 1, 1R, 2, 3, 4 & 5] Nonpotable water shall not be piped for drinking, washing or bathing, wash- ing of clothing, cooking, washing of food, washing of cook- ing or eating utensils, washing of food preparation or processing premises, or other personal service rooms. 615.2 [OSHPD 1, 1R, 2, 3, 4 & 5] Non-potable water sys- tems or systems carrying any other non-potable substance shall be installed so as to prevent backflow or back-siphonage into a potable water system. 615.3 [OSHPD 1, 1R, 2, 3, 4 & 5] Outlets for non-potable water, such as water for industrial or fire-fighting purposes,
shall be posted in a manner understandable to all employees to indicate that the water is unsafe and shall not be used for drink- ing, washing, cooking or other personal service purposes.
616.0 Emergency Water Supply. [OSHPD 1] 616.1 For new acute care hospital buildings submitted after the effective date of this code, the hospital shall have an on- site water supply sufficient to operate essential hospital util- ities and equipment in the acute care hospital building, to support 72 hours of continuing operation in the event of an _emergency.
CPC § 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
CPC § 1213.6.2.1 Medium 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 § 8.3.1.3 Medium 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 § 8.3.1 Medium relevance — show source text
[NFPA 54: TABLE 8.3.1]*
For SI units: 1 inch = 25 mm, 1 foot = 304.8 mm
- CSST EHD size of 62 is equivalent to nominal 2 inches (50 mm) pipe or tubing size.
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FUEL GAS PIPING
1213.6.1 is placed in operation, the air in the piping shall first be displaced with an inert gas. The inert gas shall then be displaced with fuel gas in accordance with Section 1213.6.1.4. [NFPA 54:8.3.1.2]
1213.6.1.4 Outdoor Discharge of Purged Gases. The open end of a piping system being pressure vented or purged shall discharge directly to an outdoor location. Purging operations shall comply with all of the following requirements:
(1) The point of discharge shall be controlled with a shutoff valve.
(2) The point of discharge shall be located at least 10 feet (3048 mm) from sources of ignition, at least 10 feet (3048 mm) from building openings and at least 25 feet (7620 mm) from mechanical air intake openings.
(3) During discharge, the open point of discharge shall be continuously attended and monitored with a combustible gas indicator that complies with Section 1213.6.1.5.
(4) Purging operations introducing fuel gas shall be stopped when 90 percent fuel gas by volume is detected within the pipe.
(5) Persons not involved in the purging operations shall be evacuated from all areas within 10 feet
(3048 mm) of the point of discharge. [NFPA 54:8.3.1.3]
1213.6.1.5 Combustible Gas Indicator. Com bustible gas indicators shall be listed and calibrated in accordance with the manufacturer’s instructions.
Combustible gas indicators shall numerically display a volume scale from 0 percent to 100 percent in 1 percent or smaller increments. [NFPA 54:8.3.1.4]
1213.6.2 Piping Systems Allowed to be Purged Indoors or Outdoors. The purging of piping systems shall be in accordance with the provisions of Section 1213.6.2.1 where the piping system meets both of the following:
(1) The design operating pressure is 2 psig (14 kPag) or less.
(2) The piping being purged is constructed entirely from pipe or tubing not meeting the size and length criteria of Table 1213.6.1. [NFPA 54:8.3.2]
1213.6.2.1 Purging Procedure. The piping system shall be purged in accordance with one or more of the following:
(1) The piping shall be purged with fuel gas and shall discharge to the outdoors.
(2) The piping shall be purged with fuel gas and shall discharge to the indoors or outdoors through an appliance burner not located in a combustion chamber. Such burner shall be provided with a continuous source of ignition.
CPC § 1313.6.2 Medium relevance — show source text
1313.6.2 Piping Systems Allowed to be Purged Indoors or Outdoors. The purging of piping systems shall be in accordance with the provisions of Section 1313.6.2.1 where the piping system meets both of the following: (1) The design operating pressure is 2 psig (14 kPag) or less.
(2) The piping being purged is constructed entirely from pipe or tubing not meeting the size and length criteria of Table 1313.6.1. [NFPA 54:8.3.2] 1313.6.2.1 Purging Procedure. The piping system shall be purged in accordance with one or more of the following: (1) The piping shall be purged with fuel gas and shall discharge to the outdoors. (2) The piping shall be purged with fuel gas and shall discharge to the indoors or outdoors through an appliance burner not located in a combustion chamber. Such burner shall be provided with a continuous source of ignition. (3) The piping shall be purged with fuel gas and shall discharge to the indoors or outdoors through a burner that has a continuous source of ignition and that is designed for such purpose. (4) The piping shall be purged with fuel gas that is discharged to the indoors or outdoors, and the point of discharge shall be monitored with a listed combustible gas detector in accordance with Section 1313.6.2.2. Purging shall be stopped when fuel gas is detected. (5) The piping shall be purged by the gas supplier in accordance with written procedures. [NFPA 54:8.3.2.1] 1313.6.2.2 Combustible Gas Detector. Combustible gas detectors shall be listed and calibrated or tested in accordance with the manufacturer’s instructions. Combustible gas detectors shall be capable of indicating the presence of fuel gas. [NFPA 54:8.3.2.2] 1313.6.3 Purging Appliances and Equipment. After the piping system has been placed in operation, appliances and equipment shall be purged before being placed into operation. [NFPA 54:8.3.3]
1314.0 Required Gas Supply. 1314.1 General. The following regulations, shall comply with this section and Section 1315.0, shall be the standard for the installation of gas piping. Natural gas regulations and tables are based on the use of gas having a specific gravity of 0.60 and for undiluted liquefied petroleum gas having a specific gravity of 1.50. Where gas of a different specific gravity is to be delivered, the serving gas supplier shall be permitted to be contacted for specific gravity conversion factors to use in sizing piping systems from the pipe sizing tables in this chapter. 1314.2 Volume. The hourly volume of gas required at each piping outlet shall be taken as not less than the maximum hourly rating as specified by the manufacturer of the appliance or appliances to be connected to each such outlet.
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FUEL GAS PIPING
CPC § 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
CPC § 1324.5.8 Medium relevance — show source text
1324.5.8 Particulate Matter. In order to remove any traces of particulate matter deposited in the pipelines as a result of construction, a heavy, intermittent purging of the pipeline shall be done. [NFPA 99:5.1.12.4.6]
1324.5.9 Final Tie-In Test. Each joint in the final connection between the new work and the existing system shall be leak-tested with the gas of system designation at the normal operating pressure by means of a leak detectant that is safe for use with oxygen and does not contain ammonia. [NFPA 99:5.1.12.4.9.2]
1324.5.9.1 Vacuum Joints. Vacuum joints shall be tested using an ultrasonic leak detector or other means that will allow detection of leaks in an active
vacuum system. [NFPA 99:5.1.12.4.9.3] 1324.5.9.2 Pressure Gases. For pressure gases, immediately after the final brazed connection is made and leak-tested, an outlet in the new piping and an outlet in the existing piping that are immediately downstream from the point or area of intrusion shall be purged in accordance with the applicable requirements of Section 1324.5.8. [NFPA 99:5.1.12.4.9.4]
1324.5.9.3 Positive Pressure Gases. Before the new work is used for patient care, positive pressure gases shall be tested for operational pressure and gas concentration in accordance with Section 1324.5.10 and Section 1324.5.11. [NFPA 99:5.1.12.4.9.5]
1324.5.9.4 Permanent Records. Permanent
records of these tests shall be maintained in accordance with NFPA 99. [NFPA 99:5.1.12.4.9.6]
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HEALTH CARE FACILITIES AND MEDICAL GAS AND MEDICAL VACUUM SYSTEMS
1324.5.10 Operational Flow Pressure Drop Test. Operational flow pressure drop tests shall be performed at each station outlet/inlet or terminal where the user
makes connections and disconnections. [NFPA 99: 5.1.12.4.10]
1324.5.10.1 Medical-Surgical Vacuum Inlets. Medical-surgical vacuum inlets shall draw 3 SCFM (85 Nl/min) without reducing the vacuum pressure below 12 inch (305 mm) gauge HgV at any adjacent station inlet. [NFPA 99:5.1.12.4.10.4]
1324.5.10.2 Oxygen and Medical Air Outlets. Oxygen and medical air outlets serving Category 1 space shall allow a transient flow rate of 6 SCFM (170 SLPM) for 3 seconds. [NFPA 99:5.1.12.4.10.5]
1324.5.11 Medical Gas Concentration Test. After
purging each system with the gas of system designation, the following shall be performed:
(1) Each pressure gas source and outlet shall be analyzed for concentration of gas, by volume.
(2) Analysis shall be conducted with instruments designed to measure the specific gas dispensed.
Frequently asked questions
Who is required to perform the purge and leak check?
The installer or permit holder is responsible for performing leak tests and purging in accordance with § 1213.4 – § 1213.6; specific tasks (e.g., gas‑supplier purging) may be performed by the gas supplier when allowed by the procedures in § 1213.6.2.1(5).
Can I purge a large diameter line inside a building if it’s low pressure?
No — if a section meets the size/length thresholds in Table 1213.6.1 (for example, ≥ 8 in any length, or 4–6 in > 15 ft) it requires outdoor purging regardless of pressure per § 1213.6.1. Indoor purging is only allowed when pressure ≤ 2 psig and the piping does not meet Table 1213.6.1 criteria (§ 1213.6.2).
What instrument is required to monitor an outdoor purge?
A listed, calibrated combustible gas indicator that displays 0–100% in 1% increments is required and must be used continuously during discharge (see § 1213.6.1.5).
When must I stop introducing fuel gas during a purge?
Stop the purging operation introducing fuel gas when 90% fuel gas by volume is detected in the pipe, per § 1213.6.1.4.
Is displacement with water acceptable when removing piping?
Yes — § 1213.6.1.2 permits purging with air, water, or inert gas before cutting or welding piping that contained gas.
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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