CPC · California Plumbing Code

Where to find piping identification/labeling and related section pointers

Q: Where in the CPC is the definitive color scheme for pipe labels?

The CPC itself references the industry standard ASME A13.1 for color and banding rules; use ASME A13.1 unless a CPC section or the AHJ requires a different scheme.

Q: Does the CPC require factory (manufacturer) markings on every pipe length?

Yes — § 301.2.1 requires manufacturer-applied markings per the applicable referenced standard; field markings are not acceptable as a substitute.

Q: Where does the CPC require labels/signage for reclaimed or gray water systems?

Chapter 15 contains the identification and signage requirements for alternate water sources; see § 1501.4 and § 1501.9 .

Q: Are there special labeling rules for medical gas piping?

Yes — Chapter 13 (medical gas and vacuum) contains required labeling and operating-pressure identification, e.g., § 1323.13 and related sections.

Q: I can’t find § 310.11 and § 310.12 in the snippets — what should I do?

The retrieved files used here did not include the text for § 310.11 and § 310.12 , so I cannot summarize or quote them. Look them up in the CPC volume or consult the Authority Having Jurisdiction for the exact language.

This guide shows where the California Plumbing Code requires piping and component identification (notably **§ 601.3.3**, **§ 1501.4**, and signage **§ 1501.9**) and points you to the referenced standard **ASME A13.1** for color/label format; manufacturer marks are required by **§ 301.2.1**, and special systems (medical gas, regulated occupancies) have their own CPC sections to follow.

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Last reviewed: July 6, 2026

What the code requires

In short: the California Plumbing Code requires that certain piping systems and components be identified or marked and directs users to specific chapters for special systems. Key places that call out identification are § 1501.4 (component identification for alternate water sources), the general identification pointer § 601.3.3, and referenced industry standard ASME A13.1 for a piping identification scheme; see the CPC index and referenced standards for where those apply.

The single most important rule: if the CPC explicitly requires identification for a system or component, follow the CPC section cited and the referenced standard (commonly ASME A13.1) — do not rely on field-only markings or unapproved manufacturer marks.

Requirements in detail

Where the CPC talks about identification (short map)

General product marking (manufacturer marking on pipe, fittings, fixtures): § 301.2.1 — manufacturer-applied markings required; field markings not acceptable.
General piping identification pointer: § 601.3.3 — index/reference entry for identification of piping (use this to find the detailed rule in Chapter 6).
Alternate water sources / nonpotable systems: § 1501.4 (component identification) and § 1501.9 (signage) — Chapter 15 requires component identification and signage for alternate water systems.
Referenced identification scheme: ASME A13.1 (listed in the CPC referenced standards) — commonly used for color bands/legend.
Medical gas and vacuum systems: labeling and operating-pressure identification are in Chapter 13 medical gas sections (for example § 1323.13 and related sections).
Occupancy-specific notes: some occupancy subsections such as § 310.13, § 310.14, and § 310.15 include special limitations or references for plastic piping, services/systems, and equipment rooms for regulated structures (Office of the State Fire Marshal / OSHPD). Use these when the project is subject to those agencies.

Decision table — what to check and where

System / situation	Decision-relevant dimension(s)	What to look for (action)	Code Reference
Manufacturer marking on pipe/fittings	Is the product listed/third‑party certified and marked?	Require manufacturer/standard markings; do not accept field-stenciled product IDs in lieu of factory marks	§ 301.2.1
Building piping (general)	Piping serving potable or nonpotable systems	Confirm identification requirements for the particular piping type in Chapter 6 and mark per the cited sections / referenced standards	§ 601.3.3
Alternate water sources (reclaimed/gray/other nonpotable)	Components, signage, and separation	Identify components and provide signage/labels as required in Chapter 15; follow component-identification and signage rules	§ 1501.4 and § 1501.9
Medical gas / vacuum piping	Label identity and operating pressure	Mark lines, indicate operating pressure and gas identity per medical gas chapter requirements	§ 1323.13–1323.15
Color/band scheme and label format	Want standard colors/placement	Use referenced standard ASME A13.1 for color bands, legends, and band placement unless CPC section gives explicit alternative	ASME A13.1 (listed in CPC referenced standards)
Occupancy- or agency‑specific limits	OSHPD / SFM regulated buildings	Check occupancy subsections — § 310.13, § 310.14, § 310.15 contain special rules and cross‑references for regulated structures (see OSHPD / SFM notes)	§ 310.13, § 310.14, § 310.15

What the CPC does NOT always prescribe

The CPC frequently requires identification or signage but often references recognized standards (for example ASME A13.1) for exact color, legend size, band width, and placement. When the CPC is silent about label size or color, default to the referenced standard identified in Table 1701.1.

Exceptions & special cases

State agency regulation: Where a section is annotated with SFM/OSHPD ([SFM] or [OSHPD] marks), that section is specific to structures regulated by that state agency. For example § 310.13 applies to SFM-regulated applications and restricts exposed plastic piping as interior finish (flame-spread > 75) — this is not a piping-identification rule but affects where piping may be exposed/visible for labeling.
Alternate water systems: Chapter 15 includes special identification and signage requirements for nonpotable systems — these override generic identification if there is a conflict. § 1501.4 and § 1501.9 are the primary CPC hooks for nonpotable component identification and signage.
Medical gas: Medical gas systems have their own labeling and operating-pressure marking requirements in Chapter 13 (see § 1323.13 and related). These are system‑specific and more prescriptive.

If you need the exact wording of § 310.11 or § 310.12, note: those specific subsections were not available in the retrieved CPC snippets I searched; I cannot quote or summarize them safely from the files I retrieved. Look them up in the CPC book or the AHJ for the full text. (The CPC file snippets I retrieved do include § 310.13–310.15.)

Common mistakes

Assuming the CPC prescribes label color and layout — often it references ASME A13.1 for those details; designers who ignore the standard end up with inconsistent or rejected labels.
Accepting field-applied product markings instead of manufacturer-applied factory marks required by § 301.2.1.
Failing to follow Chapter 15 sign wording/placement for alternate water sources — omission can lead to code violations and cross-connection concerns. § 1501.4/§ 1501.9 cover these expectations.
Treating occupancy subsections like § 310.13–310.15 as optional — they contain mandatory restrictions and cross-references for regulated occupancies (SFM/OSHPD).

Worked example

Scenario: A designer is installing a small reclaimed‑water loop for landscape irrigation on a commercial site.

Confirm the CPC chapter that covers alternate water sources and component identification: § 1501.4 (component identification) and § 1501.9 (signage). Use those sections to determine that components and points of connection must be identified and signed.
For the piping legend (color and banding), the CPC points to referenced standards such as ASME A13.1 for the accepted scheme. Apply ASME A13.1 colors for “reclaimed/irrigation” or use the specific wording required by § 1501.9 if given.
Verify that all pipe products have factory markings per § 301.2.1; do not accept only field-stenciled IDs on newly installed pipe.

Numbers/outputs you can use in documentation (example only — follow ASME A13.1 for exact band widths): label the riser and every floor penetration, provide signs at service valves and at the point of connection to the potable system, and note system identity and “NONPOTABLE — DO NOT DRINK” as required by Chapter 15 signage language. Check with the Authority Having Jurisdiction for sign size and exact text if the CPC section does not specify dimensions.

Related provisions (quick list)

§ 301.2.1 — Manufacturer marking and product identification requirements.
§ 601.3.3 — Identification of piping (index/location in CPC).
§ 1501.4 — Component identification for alternate water sources.
§ 1501.9 — Signage for alternate water sources (Chapter 15).
ASME A13.1 — Referenced piping identification standard listed in CPC Table of referenced standards.
§ 1323.13 – § 1323.15 — Medical gas piping labeling and identification requirements (Chapter 13).
§ 310.13, § 310.14, § 310.15 — Occupancy / agency‑specific notes (SFM/OSHPD) that can affect exposed piping and equipment rooms; see these for regulated-building limits and cross-references.

Code references

Grounded in the retrieved California Plumbing Code — click a citation to read the verbatim passage:

CPC § 3-5 High relevance — show source text
304 Business Group B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5

305 Educational Group E . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5

306 Factory Group F . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6

307 High-Hazard Group H . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7

308 Institutional Group I . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-13

309 Mercantile Group M. . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-14

310 Residential Group R. . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-15

311 Storage Group S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-17

312 Utility and Miscellaneous Group U . . . . . . . . . . . . . . 3-18

313 Laboratories Group L [SFM]. . . . . . . . . . . . . . . . . . . . . . .3-19

314 Organized Camps Group C [SFM]. . . . . . . . . . . . . . . . . .3-19

CHAPTER 4 SPECIAL DETAILED REQUIREMENTS

BASED ON OCCUPANCY AND USE . . . . . . . . . . . . . . . . . . . .4-1

401 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-5

402 Covered Mall and Open Mall Buildings . . . . . . . . . . . . 4-5

403 High-Rise Buildings and Group I-2 Occupancies Having Occupied Floors Located More Than 75 Feet above the Lowest Level of

Fire Department Vehicle Access . . . . . . . . . . . . . . . 4-9

404 Atriums. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-12

405 Underground Buildings . . . . . . . . . . . . . . . . . . . . . . . . 4-13

406 Motor-Vehicle-Related Occupancies. . . . . . . . . . . . . 4-15

407 Group I-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-19

408 Group I-3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-24
CPC § 1501.0 Medium relevance — show source text
1501.0 General . . . . . . . . . . . . . . . . . . . . .309

1501.1 Applicability . . . . . . . . . . . . . . . . . .309

1501.2 System Design . . . . . . . . . . . . . . .309

1501.3 Permit . . . . . . . . . . . . . . . . . . . . . .309

1501.4 Component Identification . . . . . . .309

1501.5 Maintenance and Inspection . . . .309

1501.6 Operation and Maintenance Manual . . . . . . . . . . . . . . . . . . . . .309

1501.7 Minimum Water Quality Requirements . . . . . . . . . . . . . . . .309

Table 1501.5 Recommended Minimum Alternate Water Source Testing, Inspection, and Maintenance Frequency . . . . . . . . . . . . . . . . . . .310

1501.8 Material Compatibility . . . . . . . . . .310

1501.9 Signage . . . . . . . . . . . . . . . . . . . .310

1501.10 System Controls . . . . . . . . . . . . . .310

1502.0 Inspection and Testing . . . . . . . . .310

1502.1 General . . . . . . . . . . . . . . . . . . . . .310

1502.2 Supply System Inspection and Test . . . . . . . . . . . . . . . . . . . .310

1502.3 Cross-Connection

Inspection and Testing . . . . . . . . .310

1502.4 Separation Requirements . . . . . . .311

1502.5 Abandonment . . . . . . . . . . . . . . . .311

1502.6 Sizing . . . . . . . . . . . . . . . . . . . . . .312

1503.0 Gray Water Systems . . . . . . . . . .312

1503.1 General . . . . . . . . . . . . . . . . . . . . .312

1503.2 System Requirements . . . . . . . . .313

1503.3 Connections to Potable and

Reclaimed (Recycled) Water Systems . . . . . . . . . . . . . . . . . . . . .313

1503.4 Location . . . . . . . . . . . . . . . . . . . .313

1503.5 Plot Plan Submission . . . . . . . . . .313

1503.6 Prohibited Location . . . . . . . . . . . .313

Table 1503.4 Location of Gray Water System . . .314

1503.7 Drawings and Specifications . . . .314

1503.8 Procedure for Estimating Gray Water Discharge . . . . . . . . .314

1503.9 Gray Water System Components . . . . . . . . . . . . . . . . .315

1504.0 Subsurface Irrigation System Zones . . . . . . . . . . . . . . . .316

1504.1 General . . . . . . . . . . . . . . . . . . . . .316
CPC § 1-33 Medium relevance — show source text
112 Service Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-33

113 Means of Appeals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-33

114 Violations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-34

115 Stop Work Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-34

CHAPTER 2 DEFINITIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . .2-1

201 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11

202 Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11

CHAPTER 3 OCCUPANCY CLASSIFICATION AND USE . . . . .3-1

301 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3

302 Occupancy Classification and Use Designation . . . . 3-3

303 Assembly Group A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3

304 Business Group B. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5

305 Educational Group E . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5

306 Factory Group F . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6

307 High-Hazard Group H . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7

308 Institutional Group I . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-13

309 Mercantile Group M. . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-14

310 Residential Group R. . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-15

311 Storage Group S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-17

312 Utility and Miscellaneous Group U . . . . . . . . . . . . . . 3-18

313 Laboratories Group L [SFM]. . . . . . . . . . . . . . . . . . . . . . .3-19
California Plumbing Code Medium relevance — show source text
GYPSUM SHEATHING| |PANEL
GRADE|MINIMUM
NOMINAL
PANEL
THICKNESS
(inch)|MINIMUM
FASTENER
PENETRATION
IN FRAMING
(inches)|Staple
length
and
gageh
(inches)|Fastener spacing at panel edges
(inches)|Fastener spacing at panel edges
(inches)|Fastener spacing at panel edges
(inches)|Fastener spacing at panel edges
(inches)|Staple
length
and
gageh
(inches)|Fastener spacing at panel edges
(inches)|Fastener spacing at panel edges
(inches)|Fastener spacing at panel edges
(inches)|Fastener spacing at panel edges
(inches)| |PANEL
GRADE|MINIMUM
NOMINAL
PANEL
THICKNESS
(inch)|MINIMUM
FASTENER
PENETRATION
IN FRAMING
(inches)|Staple
length
and
gageh
(inches)|6|4|3|2d|2d|6|4|3|2d| |Structural I
sheathing|3/8|1|11/2 16
Gage|155|235|315|400|2 16
Gage|155|235|310|400| |Structural I
sheathing|7/16|7/16|7/16|170|260|345|440|440|155|235|310|400| |Structural I
sheathing|15/32|15/32|15/32|185|280|375|475|475|155|235|300|400| |Sheathing,
plywood
sidinge
except
Group 5
Species,
ANSI/APA
PRP 210
sidinge|5/16
c or1/4
c|1|11/2 16
Gage|145|220|295|375|2 16
Gage|110|165|220|285| |Sheathing,
plywood
sidinge
except
Group 5
Species,
ANSI/APA
PRP 210
sidinge|3/8|3/8|3/8|140|210|280|360|360|140|210|280|360| |Sheathing,
plywood
sidinge
except
Group 5
Species,
ANSI/APA
PRP 210
sidinge|7/16|7/16|7/16|155|230|310|395|395|140|210|280|360| |Sheathing,
CPC § 1404.5 Medium relevance — show source text
1404.5 Insulation and Coverings . . . . . . .305

1404.6 Sleeves . . . . . . . . . . . . . . . . . . . . .305

1405.0 Noncombustible Piping Installations . . . . . . . . . . . . . . . . . .305

1405.1 General Requirements . . . . . . . . .305

1405.2 Fire-Resistance Rating . . . . . . . . .305

1405.3 Firestop Systems . . . . . . . . . . . . .305

1405.4 Connections . . . . . . . . . . . . . . . . .305

1405.5 Unshielded Couplings . . . . . . . . . .306

1405.6 Sleeves . . . . . . . . . . . . . . . . . . . . .306

1405.7 Insulation and Coverings . . . . . . .306

1406.0 Required Inspection . . . . . . . . . . .306

1406.1 General . . . . . . . . . . . . . . . . . . . . .306

1406.2 Examination . . . . . . . . . . . . . . . . .306

1406.3 Penetrations . . . . . . . . . . . . . . . . .306

1406.4 Field Installations . . . . . . . . . . . . .306

CHAPTER 15 ALTERNATE WATER SOURCES

FOR NONPOTABLE

APPLICATIONS . . . . . . . . . . . . . .307

1501.0 General . . . . . . . . . . . . . . . . . . . . .309

1501.1 Applicability . . . . . . . . . . . . . . . . . .309

1501.2 System Design . . . . . . . . . . . . . . .309

1501.3 Permit . . . . . . . . . . . . . . . . . . . . . .309

1501.4 Component Identification . . . . . . .309

1501.5 Maintenance and Inspection . . . .309

1501.6 Operation and Maintenance Manual . . . . . . . . . . . . . . . . . . . . .309

1501.7 Minimum Water Quality Requirements . . . . . . . . . . . . . . . .309

Table 1501.5 Recommended Minimum Alternate Water Source Testing, Inspection, and Maintenance Frequency . . . . . . . . . . . . . . . . . . .310

1501.8 Material Compatibility . . . . . . . . . .310

1501.9 Signage . . . . . . . . . . . . . . . . . . . .310

1501.10 System Controls . . . . . . . . . . . . . .310

1502.0 Inspection and Testing . . . . . . . . .310

1502.1 General . . . . . . . . . . . . . . . . . . . . .310

1502.2 Supply System Inspection and Test . . . . . . . . . . . . . . . . . . . .310

1502.3 Cross-Connection
CPC § 1211.2 Medium relevance — show source text
Where any CSST component of a piping system does not have an arcresistant jacket or coating system, the bonding requirements of Section 1211.2 shall apply. Arc-resistant jacketed CSST shall be considered to be bonded when it is connected to appliances that are connected to the appliance grounding conductor of the circuit supplying that appliance. [NFPA 54:7.12.3] 1211.4 Prohibited Use. Gas piping shall not be used as a grounding conductor or electrode. [NFPA 54:7.12.4.1] 1211.5 Lightning Protection System. Where a lightning protection system is installed, the bonding of the gas piping shall be in accordance with NFPA 780. [NFPA 54:7.12.5]

1211.6 Electrical Circuits. Electrical circuits shall not utilize gas piping or components as conductors. Exception: Low-voltage (50 V or less) control circuits, ignition circuits, and electronic flame detection device circuits shall be permitted to make use of piping or components as a part of an electric circuit. [NFPA 54:7.13] 1211.7 Electrical Connections. All electrical connections between wiring and electrically operated control devices in a

piping system shall conform to the requirements of Califor- nia Electrical Code . [NFPA 54:7.14.1] 1211.7.1 Safety Control. Any essential safety control depending on electric current as the operating medium shall be of a type that shuts off (fail safe) the flow of gas in the event of current failure. [NFPA 54:7.14.2] 1211.8 Earthquake-Actuated Gas Shutoff Valves. Earthquake-actuated gas shutoff valves designed to auto- matically shut off the gas at the location of the valve in the event of a seismic disturbance and certified by the State Architect as conforming to California Code of Regulations, Title 24, Part 12, Chapter 12-16-1, shall be provided for buildings when such installation is required by local ordi- nance. Earthquake-actuated gas shutoff valves which have not been certified by the State Architect shall be prohibited in buildings open to the public under mandatory installation by local ordinance. Installation of the valves shall be in accordance with local ordinance, and in the absence of such per the manufacturer’s installation instructions.

1212.0 Appliance and Equipment Connections to Building Piping. 1212.1 Connecting Appliances and Equipment. Appliances and equipment shall be connected to the building piping in compliance with Section 1212.6 through Section 1212.8 by one of the following: (1) Rigid metallic pipe and fittings. (2) Semirigid metallic tubing and metallic fittings. Aluminum alloy tubing shall not be used in exterior locations. (3) A connector for gas appliances listed in accordance with ANSI Z21.24/CSA 6.10. The connector shall be used in
CPC § 605.11.2 Medium relevance — show source text
accordance with ASTM F2389 or CSA B137.11.

605.11.2 Mechanical and Compression Sleeve Joints. Mechanical and compression sleeve joints shall

be installed in accordance with the manufacturer’s instal lation instructions.

605.11.3 Threaded Joints. PP pipe shall not be threaded. PP transition fittings for connection to other piping materials shall only be threaded by use of copper alloy or stainless steel inserts molded in the fitting. 605.12 PVC Plastic Pipe and Joints. PVC plastic pipe and fitting joining methods shall be installed in accordance with the manufacturer’s installation instructions and shall comply with Section 605.12.1 through Section 605.12.3. PVC piping shall not be exposed to direct sunlight.

Exception: PVC piping in a location exposed to direct sunlight shall not exceed 24 inches (610 mm) in length and be wrapped with not less than 0.04 of an inch (1.02 mm) thick UV resistant tape or otherwise protected from UV degradation . 605.12.1 Mechanical Joints. Mechanical joints shall be designed to provide a permanent seal and shall be of the mechanical or push-on joint. The mechanical joint shall include a pipe spigot that has a wall thickness to withstand without deformation or collapse; the compressive force exerted where the fitting is tightened. The push-on joint shall have a minimum wall thickness of the bell at any point between the ring and the pipe barrel. The elastomeric gasket shall comply with ASTM D3139, and be of such size and shape as to provide a compressive force against the spigot and socket after assembly to provide a positive seal.

605.12.2 Solvent Cement Joints. Solvent cement joints for PVC pipe and fittings shall be clean from dirt and moisture. Pipe shall be cut square and pipe shall be deburred. Where surfaces to be joined are cleaned and free of dirt, moisture, oil, and other foreign material, apply primer purple in color that complies with ASTM F656. Primer shall be applied to the surface of the pipe and fitting is softened. Solvent cement that complies with ASTM D2564 shall be applied to all joint surfaces. Joints shall be made while both the inside socket surface and outside surface of pipe are wet with solvent cement. Hold joint in place and undisturbed for 1 minute after assembly.

[HCD 1 & HCD 2] Plastic pipe and fittings joined with solvent cement shall utilize Low VOC primer(s), if a primer is required, and Low VOC solvent cement(s) as defined in Section 214.0. 605.12.3 Threaded Joints. Threads shall comply with ASME B1.20.1. A minimum of Schedule 80 shall be permitted to be threaded; however, the pressure rating shall be reduced by 50 percent. The use of molded fittings shall not result in a 50 percent reduction in the pressure rating of the pipe provided that the molded fittings shall be fabricated so that the wall thickness of the material is maintained at the threads. Thread sealant compound that is compatible with the pipe and fitting, insoluble in water and nontoxic shall be applied to male threads. Caution shall be used during assembly to prevent over tightening of the PVC components once the thread sealant has been applied. Female PVC threaded fittings shall be used with plastic male threads only. 605.13 Stainless Steel Pipe and **Joints.

CPC § 1-2016 Medium relevance — show source text

Col1	STANDARDS, PUBLICATIONS, PRACTICES, AND GUIDES	Col3
DOCUMENT NUMBER	DOCUMENT TITLE	APPLICATION
AHAM	AHAM	AHAM
AHAM FWD-1-2016	Food Waste Disposers	Appliances
ARCSA	ARCSA	ARCSA
ARCSA/ASPE 78-2015	Stormwater Harvesting System Design for Direct End-Use Applications	Miscellaneous
ASABE	ASABE	ASABE
ASABE/ICC 802-2014	Landscape Irrigation Sprinkler and Emitter Standard	Irrigation
ASCE	ASCE	ASCE
ASCE 25-2016	Earthquake-Actuated Automatic Gas Shutoff Devices	Fuel Gas
ASHRAE	ASHRAE	ASHRAE
ASHRAE/IES 90.1-2019	Energy Standard for Buildings Except Low-Rise Residential Buildings	Miscellaneous
ASHRAE/IES 90.2-2018	Energy-Efficient Design of Low-Rise Residential Buildings	Miscellaneous
ASHRAE 188-2021	Legionellosis: Risk Management for Building Water Systems	Risk Management
ASHRAE Guideline 12- 2020	Managing the Risk of Legionellosis Associated with Building Water Systems	Risk Management
ASME	ASME	ASME
ASME A13.1-2020	Scheme for the Identification of Piping Systems	Piping
ASME A112.4.3-1999 (R2019)	Plastic Fittings for Connecting Water Closets to the Sanitary Drainage System	Fittings
ASME A112.19.10-2017	Retrofit Dual Flush Devices for Water Closets	Fixtures
ASME A112.21.3M-1985 (R2017)	Hydrants for Utility and Maintenance Use	Valves
ASME B1.20.3-1976 (R2018)	Dryseal Pipe Threads (Inch)	Joints
ASME B16.39-2019	Malleable Iron Threaded Pipe Unions: Classes 150, 250 and 300	Fittings
ASME B16.40-2019	Manually Operated Thermoplastic Gas Shutoffs and Valves in Gas Distribution Sys- tems	Valves
ASME B31.1-2020	Power Piping	Piping
ASME B36.19M-2018	Stainless Steel Pipe	Piping, Ferrous
ASME BPVC Section IV- 2021	Rules for Construction of Heating Boilers	Miscellaneous
ASPE	ASPE	ASPE
ARCSA/ASPE 78-2015	Stormwater Harvesting System Design for Direct End-Use Applications	Miscellaneous
WQA/ASPE/ANSI S-803- 2017	Sustainable Drinking Water Treatment Systems	Miscellaneous
ASSE	ASSE	ASSE
ASSE 1017-2009	Temperature Actuated Mixing Valves for Hot Water Distribution Systems	Valves
ASSE 1066-1997	Individual Pressure Balancing In-Line Valves for Individual Fixture Fittings	Valves
ASSE

CPC § 1504.9.1 Medium relevance — show source text
Future connections . . . . . . . . . . . . . . . . . . . . .1504.9.1

Identification of piping . . . . . . . . . . . . . . . . . . . . .601.3.3 Nonpotable rainwater catchment system . . . . . . . . . . .Table 1601.5, 1602.4

Potable rainwater

catchment system . . . . . . . . . . . . . . . . . . . . . .K 102.2 ANODELESS RISER, DEFINITION . . . . . . . . . . . . . . .203.0

APPLIANCES

Automatically operated . . . . . . . . . . . .509.3.4, 509.5.7.1 Categorized vent diameter/area, definition . . . . . . . . . . . . . . . . . .203.0 Connections to building fuel gas piping . . . . . . . . . . . . . . . . . . . . . . . . .1212.0

Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .203.0

Direct-vent . . . . . . . . . . . . . . . .206.0, 509.2.6, 509.5.10.1,

509.8.1, 509.12

2025 CALIFORNIA PLUMBING CODE 563

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

INDEX

In attics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .508.4

Indirect waste type . . . . . . . . . . . . . . . . . . .806.0, 807.0

In under-floor spaces . . . . . . . . . . . . . . . . . . . . . . .508.4

On roofs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .508.0

Vent Connectors . . . . . . . . . . . . . . . . . .509.10, 510.2.11

Venting of . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .509.0

APPLICATION FOR PERMIT . . . . . . . . . . . . . . . . . . .104.3

APPROVED, DEFINITION . . . . . . . . . . . . . . . . . . . . . .203.0

APPROVED TESTING

AGENCY, DEFINITION . . . . . . . . . . . . . . . . . . . . . . .203.0

AREA DRAINS . . . . . . . . . . . . . . . . . . . . . . . .203.0, 1101.15

ASBESTOS-CEMENT PIPE . . . . . . . . . . . .Table 510.1.2(5),
CPC § 1323.1.4 Medium relevance — show source text
Table 1323.1.4(3) Pressure Loss for Nitrous Oxide and Carbon Dioxide . . . . . . .291

Table 1323.1.4(4) Pressure Loss for Oxygen . . . . . . .291

Table 1323.1.4(5) Pressure Loss for Vacuum . . . . . . .292

Table 1323.1.4(6) Pressure Loss for Vacuum (Category 3) . . . . . . . . . . . . . . . . . . .292

1323.3 Location of Piping . . . . . . . . . . . . .293

1323.4 Pipe Support . . . . . . . . . . . . . . . . .293

Table 1323.4.4 Maximum Pipe Support Spacing . . . . . . . . . . . . . . . . . . . . . .293

1323.5 Frost Protection . . . . . . . . . . . . . .293

1323.6 Connectors . . . . . . . . . . . . . . . . . .294

1323.7 Prohibited System Interconnections . . . . . . . . . . . . . .294

1323.8 Manufacturer’s Instructions . . . . .294

1323.9 Changes in System Use . . . . . . . .294

1323.10 Qualifications of Installers . . . . . .294

1323.11 Qualification of Brazing Procedures and Brazing . . . . . . . .295

1323.12 Breaching or Penetrating Medical Gas Piping . . . . . . . . . . .295

1323.13 Labeling, Identification and Operating Pressure . . . . . . . . . . .295

1323.14 Identification of Shutoff Valves . . .295

1323.15 Identification . . . . . . . . . . . . . . . . .296

1324.0 Performance Criteria and Testing Category 1 (Gases, Medical Surgical Vacuum) . . . . . .296

1324.1 Where Required . . . . . . . . . . . . . .296

1324.2 Breached Systems . . . . . . . . . . . .296

1324.3 Test Gas . . . . . . . . . . . . . . . . . . . .296

1324.4 Initial Piping Blowdown . . . . . . . . .296

1324.5 Initial Pressure Tests– Medical

Gas and Vacuum Systems . . . . . .296

Table 1324.5.11 Gas Concentrations . . . . . . . . . . .299

PART III Category 2 Piped Gas and Vacuum Systems . . . . . . . . . . . .299

1325.0 Category 2 Piped Gas and Vacuum Systems . . . . . . . . . . . . .299

1325.1 General . . . . . . . . . . . . . . . . . . . . .299

1325.2 Nature of Hazards of Gas

and Vacuum Systems . . . . . . . . .299

1325.3 Central Supply Systems . . . . . . . .299

1325.4 Category 2 Medical Air Supply Systems . . . . . . . . . . . . . .299

1325.5 Oxygen Concentrators . . . . . . . . .299
CPC § 1708.2 Medium relevance — show source text
(6) Ground-heat exchanger and building piping, valves, and operating controls, shall be set, adjusted, and operating as required.

(7) The system shall be labeled at the loop charging valves with a permanent-type label, indicating the type of heat transfer fluid used. Where antifreeze is used, the labels shall indicate the antifreeze type and concentration.

(8) Supply and return lines, as well as associated isolation valves from individual boreholes or water wells, shall be identified and tagged.

(9) Supply and return lines on submerged systems shall be identified in an approved manner, at the point of entry to a surface water resource.

«

«

«

«

«

«

«

««

««

«

«

«

1708.2 Operation and Maintenance Manual. An operation and maintenance manual for the geothermal system shall be provided to the owner. The manual shall include information on required testing and maintenance of the system. Training shall be provided on the system’s operation, maintenance requirements, and on the content of the operation and maintenance manual. The operation and maintenance manual shall contain a layout of the ground-heat exchanger and building loop.

1708.3 Labeling and Marking. Ground source heat pump ground-loop system piping shall be marked with tape, metal tags, or other methods where it enters a building. The marking shall indicate the following words: “GROUND SOURCE HEAT PUMP-LOOP SYSTEM.” The marking shall indicate antifreeze used in the system by name and concentration.

1708.4 Documentation. The ground source heat pump system as-built installation drawings and instructions shall be provided to the building owner or designated agent.

1708.5 Maintenance. The periodic maintenance required, in accordance with the design requirements, shall be provided and be made available to the owner or designated agent.

1708.6 Records. The ground source heat pump system construction documents shall be provided to the owner.

1708.7 System Start-Up. System start-up shall be in accordance with ANSI/ CSA/IGSHPA C448 and Section 1708.0.

1708.8 Contaminants. Particulate contaminants shall be removed from the indoor piping system prior to initial start up.

1709.0 Decommissioning and Abandonment. 1709.1 General. Decommissioning of geothermal systems shall comply with ANSI/ CSA/IGSHPA C448. Prior to the abandonment or decommissioning of geothermal systems, the owner shall obtain the necessary permits from the Authority Having Jurisdiction.

Part II – Closed-Loop Systems.

1710.0 General.

1710.1 Applicability. Part II of this chapter shall apply to geothermal closed-loop systems such as, but not limited to, building systems coupled with a closed-loop system using water-based fluid as a heat transfer medium.

1710.2 Piping and Tubing. Piping and tubing for closedloop systems shall be in accordance Section 1703.2 and Table 1703.2.

1710.3 Borehole Piping and Tubing. Borehole piping or tubing for vertical and horizontally drilled closed-loop systems shall have a minimum wall thickness equal to SDR-11 and shall have a minimum pressure rating of not less than 160 psi (1103 kPa) at 73°F (23°C).
CPC § 301.2 Medium relevance — show source text
301.2 Minimum Standards. Pipe, pipe fittings, traps, fixtures, material, and devices used in a plumbing system shall be listed (third-party certified) by a listing agency (accredited conformity assessment body) as complying with the approved applicable recognized standards referenced in this code, and shall be free from defects. Unless otherwise provided for in this code, materials, fixtures, or devices used or entering into the construction of plumbing systems, or parts thereof shall be submitted to the Authority Having Jurisdiction for approval prior to being installed. 301.2.1 Marking. Each length of pipe and each pipe fitting, trap, fixture, material, and device used in a plumbing system shall have cast, stamped, or indelibly marked on it any markings required by the applicable referenced standards and listing agency, and the manufacturer’s mark or name, which shall readily identify the manufacturer to the end user of the product. Where required by the approved standard that applies, the product shall be marked with the weight and the quality of the product. Materials and devices used or entering into the construction of plumbing and drainage systems, or parts thereof shall be marked and identified in a manner satisfactory to the Authority Having Jurisdiction. Such marking shall be done by the manufacturer. Field markings shall not be acceptable.

Exception: Markings shall not be required on nipples created from cutting and threading of approved pipe.

301.2.2 Standards. Standards listed or referred to in this chapter or other chapters cover materials that will conform to the requirements of this code, where used in accordance with the limitations imposed in this or other chapters thereof and their listing. Where a standard covers materials of various grades, weights, quality, or configurations, the portion of the listed standard that is applicable shall be used. Design and materials for special conditions or materials not provided for herein shall be permitted to be used by special permission of the Authority Having Jurisdiction after the Authority Having Jurisdiction has been satisfied as to their adequacy. A list of plumbing standards that appear in specific sections of this code is referenced in Table 1701.1. Standards referenced in Table 1701.1 shall be applied as indicated in the applicable referenced section. A list of additional approved standards, publications, practices, and guides that are not referenced in specific sections of this code appear in Table 1701.2. An IAPMO Installation Standard is referenced in Appendix I for the convenience of the users of this code. It is not considered as a part of this code unless formally adopted as such by the Authority Having Jurisdiction.

301.2.3 Plastic Pipe, Plastic Pipe Fittings, and Components. Plastic pipe, plastic pipe fittings, and components other than those for gas shall comply with NSF/ANSI 14.

301.2.4 Cast-Iron Soil Pipe, Fittings, and Hubless Couplings. Cast-iron soil pipe, fittings, and hubless couplings shall be third party certified in accordance with ASTM C1277 and CISPI 310 for couplings and ASTM A888, ASTM A74, and CISPI 301 for pipes and fittings. 301.2.5 Existing Buildings. In existing buildings or premises in which plumbing installations are to be altered, repaired, or renovated, the Authority Having Jurisdiction has discretionary powers to permit deviation from the provisions of this code, provided that such proposal to deviate is first submitted for proper determination in order that health and safety requirements, as they pertain to plumbing, shall be observed.
CPC § 604.1 Medium relevance — show source text
(19 mm)
through 3 in. (76 mm), for Water Service|Piping|Table 604.1| |AWWA C904-2016|Crosslinked Polyethylene (PEX) Pressure Tubing,1⁄2 in.
through 3 in. (13 mm through 76 mm), for Water Service|Piping|Table 604.1| |AWWA C907-2017|Injection-Molded Polyvinyl Chloride (PVC) Pressure Fittings,
4 in. through 12 in. (100 mm through 300 mm), for Water,
Wastewater, and Reclaimed Water Service|Fittings|Table 604.1| |CFR|CFR|CFR|CFR| |49 CFR 192.281|Plastic Pipe|Plastic, Pipe|1208.5.6.2| |49 CFR 192.283|Plastic Pipe: Qualifying Joining Procedures|Plastic, Pipe|1208.5.6.2| |CGA|CGA|CGA|CGA| |CGA G-4.1-2018|Cleaning of Equipment for Oxygen Service|Miscellaneous|1318.2, 1321.8.7| |CGA M-1-2018|Medical Gas Supply Systems at Health Care Facilities|Miscellaneous|1324.5.7.3| |CGA V-5-2019|Diameter Index Safety System (Noninterchangeable Low Pres-
sure Connections for Medical Gas Applications)|Connections|1315.5| |CISPI|CISPI|CISPI|CISPI| |CISPI 301-2021|Hubless Cast Iron Soil Pipe and Fittings for Sanitary and Storm
Drain, Waste, and Vent Piping Applications|Piping, Ferrous|301.2.4, Table 701.2,
Table 707.2| |CISPI 310-2020|Couplings for Use in Connection with Hubless Cast Iron Soil
Pipe and Fittings for Sanitary and Storm Drain, Waste, and
Vent Piping Applications|Joints|301.2.4, 705.2.2| |CSA|CSA|CSA|CSA| |ASME A112.19.2-
2018/CSA B45.1-2018|Ceramic Plumbing Fixtures|Fixtures|407.1, 408.1, 409.1,
410.1, 411.1, 412.1,
415.1, 420.1| |ASME A112.19.1-
2018/CSA B45.2-2018|Enameled Cast Iron and Enameled Steel Plumbing Fixtures|Fixtures|407.1, 408.1, 409.1,
415.1, 420.1| |ASME A112.19.3-
2017/CSA B45.4-2017|Stainless Steel Plumbing Fixtures|Fixtures|407.1, 408.1, 409.1,
410.1, 411.1, 415.1,
420.1| |CSA B45.5-2017/IAPMO
Z124-2017|Plastic Plumbing Fixtures (with Errata dated August 2017)|Fixtures|407.1, 408.1, 409.1,

CPC § 301.2.4 Medium relevance — show source text

2025 CALIFORNIA PLUMBING CODE 345

REFERENCED STANDARDS

TABLE 1701.1 (continued) REFERENCED STANDARDS

STANDARD NUMBER	STANDARD TITLE	APPLICATION	REFERENCED SECTION
CSA B45.11-2017/IAPMO Z401-2017 (R2021)	Glass Plumbing Fixtures	Fixtures	407.1
CSA B45.12-2013/IAPMO Z402-2013 (R2018)	Aluminum and Copper Plumbing Fixtures	Fixtures	407.1, 408.1, 409.1, 420.1
ASME A112.19.5- 2017/CSA B45.15-2017	Flush Valves and Spuds for Water Closets, Urinals, and Tanks	Fixtures	413.3
ASME A112.4.

CPC § 309.0 Medium relevance — show source text
2025 CALIFORNIA PLUMBING CODE 469

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

IS 33

Uniform Plumbing Code References for Ductile Iron and PVC Pressure Building Supply and Exterior Cold-Water Piping

The following sections of the 2024 Uniform Plumbing Code apply to ductile iron and PVC pressure building supply and exterior cold-water piping.

Chapter 3 General Regulations

309.0 Workmanship

312.0 Protection of Piping, Materials, and Struc tures

313.0 Hangers, Supports, and Anchors

314.0 Trenching, Excavation, and Backfill

Chapter 6 Water Supply and Distribution

604.0 Materials (water piping)

Table 604.1 Materials for Building Supply and Water Distribution Piping and Fittings

605.4 Ductile Iron Pipe and Joints

605.12 PVC Plastic Pipe and Joints

605.16.2 Plastic Pipe to Other Materials

609.0 Installation, Testing, Unions, and Location

Abbreviations

IAPMO International Association of Plumbing and Mechanical Officials

UPC Uniform Plumbing Code published by IAPMO

AWWA American Water Works Association

CSA Canadian Standards Association

Applicable Standards.

ASME B16.4 Gray Iron Threaded Fittings Classes 125 and 250

ASTM D1785 Poly (Vinyl Chloride) (PVC) Plastic Pipe, Schedules 40, 80, and 120

ASTM D2241 Poly (Vinyl Chloride) (PVC) Pressure-Rated Pipe (SDR Series)

ASTM D2466 Poly (Vinyl Chloride) (PVC) Plastic Pipe Fittings, Schedule 40

ASTM D2467 Poly (Vinyl Chloride) (PVC) Plastic Pipe Fittings, Schedule 80

ASTM F1970 Special Engineered Fittings, Appurtenances or Valves for use in Poly (Vinyl Chloride) (PVC) or Chlorinated Poly (Vinyl Chloride) (CPVC) Systems

AWWA C110 Ductile Iron and Gray-Iron Fittings

AWWA C111 Rubber-Gasket Joints for Ductile-Iron Pressure Pipe and Fittings

AWWA C151 Ductile-Iron Pipe, Centrifugally Cast

AWWA C153 Ductile-Iron Compact Fitting

AWWA C900 Polyvinyl Chloride (PVC) Pressure Pipe and Fabricated Fittings, 4 in. through 12 in. (100 mm through 300 mm)

AWWA C904 Crosslinked Polyethylene (PEX) Pressure Tubing, ½ in. through 3 In. (13 mm through 76 mm), for Water Service

AWWA C907 Injection-Molded Polyvinyl Chloride (PVC) Pressure Fittings, 4 In, through 12 in (100 mm through 300 mm) for Water, Wastewater and Reclaimed Water Service

IAPMO/

ANSI UPC-1 Uniform Plumbing Code

470 2025 CALIFORNIA PLUMBING CODE

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.
CPC § 0.60 Medium relevance — show source text
60**|** 0.60**| ||PIPE SIZE (inch)|PIPE SIZE (inch)|PIPE SIZE (inch)|PIPE SIZE (inch)|PIPE SIZE (inch)|PIPE SIZE (inch)|PIPE SIZE (inch)|PIPE SIZE (inch)| |NOMINAL OD:|1⁄2|3⁄4|1|1 1⁄4|1 1⁄2|2|3|4| |DESIGNATION:|SDR 9.3|SDR 11|SDR 11|SDR 10|SDR 11|SDR 11|SDR 11|SDR 11| |ACTUAL ID:|0.660|0.860|1.077|1.328|1.554|1.943|2.864|3.682| |LENGTH (feet)|CAPACITY IN CUBIC FEET OF GAS PER HOUR|CAPACITY IN CUBIC FEET OF GAS PER HOUR|CAPACITY IN CUBIC FEET OF GAS PER HOUR|CAPACITY IN CUBIC FEET OF GAS PER HOUR|CAPACITY IN CUBIC FEET OF GAS PER HOUR|CAPACITY IN CUBIC FEET OF GAS PER HOUR|CAPACITY IN CUBIC FEET OF GAS PER HOUR|CAPACITY IN CUBIC FEET OF GAS PER HOUR| |10|153|305|551|955|1440|2590|7170|13 900| |20|105|210|379|656|991|1780|4920|9520| |30|84|169|304|527|796|1430|3950|7640| |40|72|144|260|451|681|1220|3380|6540| |50|64|128|231|400|604|1080|3000|5800| |60|58|116|209|362|547|983|2720|5250| |70|53|107|192|333|503|904|2500|4830| |80|50|99|179|310|468|841|2330|4500| |90|46|93|168|291|439|789|2180|4220| |100|44|88|159|275|415|745|2060|3990| |125|39|78|141|243|368|661|1830|3530| |150|35|71|127|221|333|598|1660|3200| |175|32|65|117|203|306|551|1520|2940| |200|30|60|109|189|285|512|1420|2740| |250|27|54|97|167|253|454|1260|2430| |300|24|48|88|152|229|411|1140|2200| |350|22|45|81|139|211|378|1050|2020| |400|21|42|75|130|196|352|974|1880| |450|19|39|70|122|184|330|914|1770| |500|18|37|66|115|174|312|863|1670|
CPC § 1323.13.3 Medium relevance — show source text
2, 1323.13.3| |1326.4 - 1326.10|1326.5 - 1326.11| |1505.6 - 1505.14|1505.5 - 1505.13| |Figure 1505.10|Figure 1505.9| |1506.6 - 1506.13|1506.5 - 1506.12| |1603.3 - 1603.4|1603.4 - 1603.5| |Table 1603.4|Table 1603.5| |1603.5 - 1603.19|1603.6 - 1603.20| |1603.20|1503.2.4| |L 402.9 - L 402.11|L 402.8 - L 402.10| |L 404.9 - L 404.12|L 404.8 - L 404.11| |L 411.5, L 411.6|L 411.2, L411.3| |L 411.7|L 411.4| |L 411.9 - L 411.12|L 411.5 - L 411.8|

xxii 2025 CALIFORNIA PLUMBING CODE

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RELATED PUBLICATIONS AND SERVICES

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IAPMO provides a variety of other products which are useful for inspectors, building officials, architects, engineers,

manufacturers, contractors, plumbers, and apprentices.

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Publication Order Desk Phone: 800-85-IAPMO

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Uniform Plumbing Code – 2024 Edition:

The Uniform Plumbing Code is the most widely adopted plumbing code in the world. The 2024 edition contains complete “turnkey” requirements for the installation and maintenance of plumbing systems, all in one easy to use book.

Uniform Plumbing Code Illustrated Training Manual:

The UPC Illustrated Training Manual is an excellent reference for anyone involved in the plumbing industry. It contains an extensive definitions section and several hundred comprehensive technical diagrams and illustrations. It serves as a textbook, and it also is useful as a valuable tool for explaining the intent and use of the Code.

Uniform Plumbing Code Study Guide:

This book is the perfect complement to the UPC Illustrated Training Manual. Alone, it constitutes a complete self-study course for learning the UPC. It has hundreds of questions, general practice exams, and plumbing math, pipe sizing exercises and fitting identification. A big help in getting you ready for a certification exam!

Guide to Important Code Questions to the Uniform Plumbing Code:

An excellent reference for learning and understanding plumbing code changes and identifies code changes between editions. It is a useful tool for preparing code change proposals.

Uniform Mechanical Code – 2024 Edition:

The Uniform Mechanical Code contains complete requirements for the installation and maintenance of heating, ventilating, cooking and refrigeration systems.

Uniform Mechanical Code Illustrated Training Manual:

Contains technical diagrams and illustrations that demonstrate the intent and use of the UMC. A great reference for everyone involved in Mechanical HVACR design and installation.

Uniform Mechanical Code Study Guide:
CPC § 4.1 Medium relevance — show source text
- 100°F
  (16°C-38°C)|1 h|6 h|2 h|12 h|6 h|24 h| |40°F-60°F
  (4°C-16°C)|2 h|12 h|4 h|24 h|12 h|48 h| |10°F- 40°F
  (-12°C+4°C)|8 h|48 h|16 h|96 h|48 h|8 days| |*If gaps or loose fits are encountered in the system, double these cure times.|*If gaps or loose fits are encountered in the system, double these cure times.|*If gaps or loose fits are encountered in the system, double these cure times.|*If gaps or loose fits are encountered in the system, double these cure times.|*If gaps or loose fits are encountered in the system, double these cure times.|*If gaps or loose fits are encountered in the system, double these cure times.|*If gaps or loose fits are encountered in the system, double these cure times.|
2025 CALIFORNIA PLUMBING CODE 467

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

IS 33

FIGURE 1

LOCATION OF THRUST BLOCKS (STANDARD AND METRIC COMBINED) A COMPARISON OF THRUST-BLOCK AREAS (See Section 4.1)

468 2025 CALIFORNIA PLUMBING CODE

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

IS 33

FIGURE 2

THRUST BLOCK BEARING AREA (See Section 5.2.2)

2025 CALIFORNIA PLUMBING CODE 469

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

IS 33

Uniform Plumbing Code References for Ductile Iron and PVC Pressure Building Supply and Exterior Cold-Water Piping

The following sections of the 2024 Uniform Plumbing Code apply to ductile iron and PVC pressure building supply and exterior cold-water piping.

Chapter 3 General Regulations

309.0 Workmanship

312.0 Protection of Piping, Materials, and Struc tures

313.0 Hangers, Supports, and Anchors

314.0 Trenching, Excavation, and Backfill

Chapter 6 Water Supply and Distribution

604.0 Materials (water piping)

Table 604.1 Materials for Building Supply and Water Distribution Piping and Fittings

605.4 Ductile Iron Pipe and Joints

605.12 PVC Plastic Pipe and Joints

605.16.2 Plastic Pipe to Other Materials

609.0 Installation, Testing, Unions, and Location

Abbreviations

IAPMO International Association of Plumbing and Mechanical Officials

UPC Uniform Plumbing Code published by IAPMO

AWWA American Water Works Association

CSA Canadian Standards Association

Applicable Standards.

ASME B16.4 Gray Iron Threaded Fittings Classes 125 and 250

ASTM D1785 Poly (Vinyl Chloride) (PVC) Plastic Pipe, Schedules 40, 80, and 120

ASTM D2241 Poly (Vinyl Chloride) (PVC) Pressure-Rated Pipe (SDR Series)

CPC § 0.6 Medium relevance — show source text

(a) be balanced to maintain adequate system temperatures; and (b) have flow velocities that do not exceed 0.6 m/s (2 ft/s) (see Table 2); and (c) use only PEX tubing designated for hot, chlorinated water recirculation systems and rated for the maximum percentage of time during which the system is intended to be operated at elevated temperatures, in accordance with ASTM F876. 10.7 Installation Testing

Installation of PEX water distribution systems may be tested with air when

(a) expressly allowed in the written instructions of the manufacturers of all plastic pipe and fittings installed at the time the PEX piping system is being tested; and (b) compressed air or other gas testing is not prohibited by the authority having jurisdiction.

Note: LB = C × √ (D × Δ L)

where

LB = length of flexible arm

C = material constant (12 for PEX)

D = nominal outside diameter of tubing

Δ L = thermal expansion length

FIGURE 1

EXPANSION ARMS

(See Sections 6.4.1 and 7.3)

2025 CALIFORNIA PLUMBING CODE 459

IS 31

TABLE 1

CALCULATION OF FLUSH TANK AND FLUSH VALVE FIXTURE UNITS

(See Section 10.6.3)

NOMINAL TUBING SIZE	FLOW VELOCITY: 3.0 m/s (10 ft/s)	Col3	Col4	FLOW VELOCITY: 2.4 m/s (8 ft/s)	Col6	Col7
NOMINAL TUBING SIZE	FLOW VOLUME, L/min (gpm)	FLUSH TANK FIXTURE UNITS	FLUSH VALVE FIXTURE UNITS	FLOW, L/min (gpm)	FLUSH TANK FIXTURE UNITS	FLUSH VALVE FIXTURE UNITS
1⁄2	20.8 (5.5)	6	—	16.7 (4.4)	4	—
3⁄4	41.6 (11.0)	15	—	33.3 (8.8)	11	—
1	68.9 (18.2)	26	—	55.3 (14.6)	20	—
11⁄4	103.0 (27.2)	46	10	82.5 (21.8)	33	5
11⁄2	143.5 (37.9)	77	24	114.7 (30.3)	54	13
2	246.1 (65.0)	200	91	196.8 (52.0)	135	52
3	533.0 (140.8)	590	495	426.2 (112.6)	443	310

TABLE 2

TUBING SIZES, FLOWS, AND FRICTION LOSSES FOR HOT-WATER RECIRCULATION SYSTEMS

CPC § 304.8 Medium relevance — show source text

77
74
71
68|142
135
129
124
120|201
192
183
176
170|429
409
392
376
363|772
737
705
678
653|1220
1160
1110
1070
1030|2540
2420
2320
2230
2140| |1600
1700
1800
1900
2000|1600
1700
1800
1900
2000|16
15
15
14
14|33
31
30
30
29|66
64
62
60
59|116
112
108
105
102|164
159
154
149
145|350
339
329
319
310|630
610
592
575
559|994
962
933
906
881|2070
2000
1940
1890
1830|

For SI units: 1 inch = 25 mm, 1 foot = 304.8 mm, 1 cubic foot per hour = 0.0283 m [3] /h, 1 pound-force per square inch = 6.8947 kPa

Notes: 1 Table capacities are based on Type K copper tubing inside diameter (shown), which has the smallest inside diameter of the copper tubing products. 2 Table entries are rounded to 3 significant digits.

2025 CALIFORNIA PLUMBING CODE 247

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

FUEL GAS PIPING
CPC § 102.3 Medium relevance — show source text
1

CEBC—25: California Existing Building Code

102.3, 1011.5.2, 1103.1, 1104.18, 1105.5.2

CMC—25: California Mechanical Code

201.3, 308.3, 605.1, 605.2.1.1, 605.2.1.2, 605.2.1.3, 605.2.1.4, 605.2.1.5, 605.3, 605.4, 605.4.2.3, 605.4.2.5, 605.5.2, 605.7, 606.1, 606.2, 608.1, 608.3, 608.4, 608.5, 608.8, 608.9.1, 608.10, 608.17, 610.1.1, 903.2.11.4, 904.14, 907.3.1, 909.1, 909.10.2, 909.13.1, 910.4.7, 915.6.1, 1006.2.2.3, 1011.16, 1020.6.1, 1207.4.7, 1207.6.1, 1207.6.1.2.2, 1207.11.8, 2104.2.1, 2105.3, 2301.1, 2301.6, 2309.3.1.2, 2311.3.1, 2311.4.3, 2311.8.2, 2311.8.8, 2311.8.10, 2404.9, 2404.9.2, 2504.5, 2703.2.2, 2703.10.4, 2703.14, 2803.2, 2803.3, 3001.1, 3003.1, 3004.2, 3108.12.1, 3108.12.2, 3703.5, 3804.1.1.7, 3904.1, 3905.3, Table 5003.1.1(1), 5003.8.4.2, 5003.8.5.2, 5003.8.6.2, 5004.3.1, 5303.7.6, 5303.16.9, 5305.5, 5306.2.2, 5306.2.3, 5307.4.4, 5504.2.1.3, 5504.2.2.3, 5505.4.1.1, 5701.3, 5703.6.1, 5704.2.8.9, 5705.3.7.5.1, 5706.2, 5706.4.4, 6003.1.3, 6003.2.3.2, 6004.2.2.7, 6005.3.1, 6005.3.2, 6103.2.1.7

CPC—25: California Plumbing Code
CPC § 0.300 Medium relevance — show source text
0 – (0.300 ×Cap/1000) EER_5|14.0 – (0.300 ×Cap/1000) EER_5| |PTAC (cooling mode) standard
size|>15 000Btu/h|>15 000Btu/h|9.5_EER|9.5_EER| |PTAC (cooling mode) nonstandard
size1|<7000 Btu/h|95°F db/75°F wb
outdoor air3|9.4_EER_|AHRI 310/ 380| |PTAC (cooling mode) nonstandard
size1|≥7000 Btu/h and
≤15 000 Btu/h|≥7000 Btu/h and
≤15 000 Btu/h|10.9 – (0.213 ×Cap/1000) EER_5|10.9 – (0.213 ×Cap/1000) EER_5| |PTAC (cooling mode) nonstandard
size1|>15 000Btu/h|>15 000Btu/h|7.7_EER|7.7_EER| |PTHP (cooling mode) standard size|<7000 Btu/h|95°F db/75°F wb
outdoor air3|11.9_EER_|AHRI 310/ 380| |PTHP (cooling mode) standard size|≥7000 Btu/h and
≤15 000 Btu/h|≥7000 Btu/h and
≤15 000 Btu/h|14.0 – (0.300 ×Cap/1000) EER_5|14.0 – (0.300 ×Cap/1000) EER_5| |PTHP (cooling mode) standard size|>15 000Btu/h|>15 000Btu/h|9.5_EER|9.5_EER| |PTHP (cooling mode) nonstandard
size2|<7000 Btu/h|95°F db/75°F wb
outdoor air3|9.3_EER_|AHRI 310/ 380| |PTHP (cooling mode) nonstandard
size2|≥7000 Btu/h and
≤15 000 Btu/h|≥7000 Btu/h and
≤15 000 Btu/h|10.8 – (0.213 ×Cap/1000) EER_5|10.8 – (0.213 ×Cap/1000) EER_5| |PTHP (cooling mode) nonstandard
size2|>15 000Btu/h|>15 000Btu/h|7.6_EER|7.6_EER| |PTHP (heating mode) standard size|<7000 Btu/h|47°F db/43°F wb
outdoor air3|3.3_COPH_|AHRI 310/ 380| |PTHP (heating mode) standard size|≥7000 Btu/h and
≤15 000 Btu/h|≥7000 Btu/h and
≤15 000 Btu/h|3.7 – (0.052 ×Cap/1000) COPH
5|3.7 – (0.
CPC § 0.300 Medium relevance — show source text
0 – (0.300 ×Cap/1000) EER_5|14.0 – (0.300 ×Cap/1000) EER_5| |PTHP (cooling mode) standard size|>15 000Btu/h|>15 000Btu/h|9.5_EER|9.5_EER| |PTHP (cooling mode) nonstandard
size2|<7000 Btu/h|95°F db/75°F wb
outdoor air3|9.3_EER_|AHRI 310/ 380| |PTHP (cooling mode) nonstandard
size2|≥7000 Btu/h and
≤15 000 Btu/h|≥7000 Btu/h and
≤15 000 Btu/h|10.8 – (0.213 ×Cap/1000) EER_5|10.8 – (0.213 ×Cap/1000) EER_5| |PTHP (cooling mode) nonstandard
size2|>15 000Btu/h|>15 000Btu/h|7.6_EER|7.6_EER| |PTHP (heating mode) standard size|<7000 Btu/h|47°F db/43°F wb
outdoor air3|3.3_COPH_|AHRI 310/ 380| |PTHP (heating mode) standard size|≥7000 Btu/h and
≤15 000 Btu/h|≥7000 Btu/h and
≤15 000 Btu/h|3.7 – (0.052 ×Cap/1000) COPH
5|3.7 – (0.052 ×Cap/1000) COPH
5| |PTHP (heating mode) standard size|>15 000Btu/h|>15 000Btu/h|2.90_COPH_|2.90_COPH_| |PTHP (heating mode) nonstandard
size2|<7000 Btu/h|47°F db/43°F wb
outdoor air3|2.7_COPH_|AHRI 310/ 380| |PTHP (heating mode) nonstandard
size2|≥7000 Btu/h and
≤15 000 Btu/h|≥7000 Btu/h and
≤15 000 Btu/h|2.9 – (0.026 ×Cap/1000) COPH_5|2.9 – (0.026 ×Cap/1000) COPH_5| |PTHP (heating mode) nonstandard
size2|>15 000Btu/h|>15 000Btu/h|2.5_COPH|2.5_COPH| |SPVAC (cooling mode) single and
three phase|<65 000 Btu/h|95°F db/75°F wb
outdoor air3|11.0_EER_|AHRI 390| |SPVAC (cooling mode) single and
three phase|≥65 000 Btu/h and
<135 000 Btu/h|≥65 000 Btu/h and
<135 000 Btu/h|10.0_EER_|10.
CPC § 2.2 Medium relevance — show source text
Certification as a Level IV Bridge Inspector by the National Institute of Certification in Engineering Technologies (NICET) shall also be acceptable [2.2].

For underwater inspections, the registered civil or structural engineer directing the underwater structural inspection shall also be a commercially trained diver or equivalent and shall actively participate in the inspection, by personally conducting a mini- mum of 25 percent of the underwater examination [2.2].

Each underwater team member shall also be a commercially trained diver, or equivalent. Divers performing manual tasks such as cleaning or supporting the diving operation, but not conducting or reporting on inspections, may have lesser technical qualifi- cations [2.2].

3102F.3.4.4 Structural analyst. A California registered civil or structural engineer shall be in responsible charge of the structural evaluations.

3102F.3.4.5 Electrical inspection team. A registered electrical engineer shall direct the on-site team performing the inspection and evaluation of electrical components and systems.

3102F.3.4.6 Mechanical inspection team. A registered engineer shall direct the on-site team performing the inspection and eval- uation of piping/pipeline, mechanical and fire components and systems, except the Fire Protection Assessment in accordance with Section 3108F.2.2.

3102F.3.4.7 Corrosion specialist. The corrosion specialist shall be a chemical engineer, corrosion engineer, chemist or other professional with expertise in the types and causes of corrosion, and available means to prevent, monitor and mitigate associated damage. The specialist shall perform the corrosion assessment (Section 3102F.3.6.5) and may be directly involved in corrosion inspection (Section 3102F.3.5.4).

3102F.3.4.8 Geotechnical analyst. A California registered civil engineer with a California authorization as a geotechnical engi- neer shall perform the geotechnical evaluation required for the audit and all other geotechnical evaluations.

3102F.3.4.9 Division representation. The Division representative(s) may participate in any audit or inspection as observer(s). The Division shall be notified in advance of audit-related inspections.

3102F.3.5 Scope of inspections.

3102F.3.5.1 Structural inspections.

3102F.3.5.1.1 Above water structural inspection. The above water inspection shall include all accessible components above and below deck that are reachable without the need for excavation or extensive removal of materials that may impair visual inspection. The above water inspection shall include, but not be limited to, the following:

1. Piles

2. Pile caps

3. Beams

4. Deck soffit

5. Bracing 6. Retaining walls and bulkheads

7. Connections

8. Seawalls

9. Slope protection 10. Deck topsides and curbing 11. Expansion joints 12. Fender system components 13. Dolphins and deadmen 14. Mooring points and hardware 15. Navigation aids 16. Platforms, ladders, stairs, handrails and gangways 17. Backfill (sinkholes/differential settlement)

CPC § 90.1 Medium relevance — show source text

3 ASHRAE 90.1 contains a complete specification of the referenced test procedure, including the referenced year version of the test procedure. 4 NA means the requirements are not applicable for Path B, and only Path A can be used for compliance. 5 FL is the full-load performance requirements, and IPLV.IP is for the part-load performance requirements.

454 2025 CALIFORNIA MECHANICAL CODE

APPENDIX E

TABLE E 503.7.1(4) ELECTRICALLY OPERATED PACKAGED TERMINAL AIR CONDITIONERS, PACKAGED TERMINAL HEAT PUMPS, SINGLE-PACKAGE VERTICAL AIR CONDITIONERS, SINGLE-PACKAGE VERTICAL HEAT PUMPS, ROOM AIR CONDITIONERS, AND ROOM AIR CONDITIONER HEAT PUMPS ─ MINIMUM EFFICIENCY REQUIREMENTS

[ASHRAE 90.1: TABLE 6.8.1-4]

EQUIPMENT TYPE	SIZE CATEGORY (INPUT)	SUBCATEGORY OR RATING CONDITION	4 MINIMUM EFFICIENCY	TEST 1 PROCEDURE
PTAC (cooling mode) standard size	<7000 Btu/h	95°F db/75°F wb outdoor air3	11.9_EER_	AHRI 310/ 380
PTAC (cooling mode) standard size	≥7000 Btu/h and ≤15 000 Btu/h	≥7000 Btu/h and ≤15 000 Btu/h	14.0 – (0.300 ×Cap/1000) _EER_5	14.0 – (0.300 ×Cap/1000) _EER_5
PTAC (cooling mode) standard size	>15 000Btu/h	>15 000Btu/h	9.5_EER_	9.5_EER_
PTAC (cooling mode) nonstandard size1	<7000 Btu/h	95°F db/75°F wb outdoor air3	9.4_EER_	AHRI 310/ 380
PTAC (cooling mode) nonstandard size1	≥7000 Btu/h and ≤15 000 Btu/h	≥7000 Btu/h and ≤15 000 Btu/h	10.9 – (0.213 ×Cap/1000) _EER_5	10.9 – (0.213 ×Cap/1000) _EER_5
PTAC (cooling mode) nonstandard size1	>15 000Btu/h	>15 000Btu/h	7.7_EER_	7.7_EER_
PTHP (cooling mode) standard size	<7000 Btu/h	95°F db/75°F wb outdoor air3	11.9_EER_	AHRI 310/ 380
PTHP (cooling mode) standard size	≥7000 Btu/h and ≤15 000 Btu/h	≥7000 Btu/h and ≤15 000 Btu/h	14.0 – (0.300 ×Cap/1000) _EER_5	14.0 – (0.

CPC § 9.6.7 Medium relevance — show source text
[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]

1213.1.1 Inspection Requirements. Inspection shall consist of visual examination, during or after manufacture, fabrication, assembly, or pressure tests. [NFPA 54:8.1.1.2]

1213.1.2 Repairs and Additions. Where repairs or additions are made following the pressure test, the affected piping shall be tested. Minor repairs and additions are not required to be pressure tested, provided that the work is inspected and connections are tested with a noncorrosive leak-detecting fluid or other leak-detecting methods approved by the Authority Having Jurisdiction.

[NFPA 54:8.1.1.3]

1213.1.3 New Branches. Where new branches are installed to new appliance(s), only the newly installed branch(es) shall be required to be pressure tested. Connections between the new piping and the existing piping shall be tested with a noncorrosive leak-detecting fluid or approved leak-detecting methods. [NFPA 54:8.1.1.4] 1213.1.4 Piping System. A piping system shall be tested as a complete unit or in sections. Under no circumstances shall a valve in a line be used as a bulkhead between gas in one section of the piping system and test medium in an adjacent section, unless a double block and bleed valve system is installed. A valve shall not be subjected to the test pressure unless it can be determined that the valve, including the valve closing mechanism, is designed to safely withstand the pressure. [NFPA 54:8.1.1.5] **1213.1.5 Regulators and Valves.
CPC § 503.5.7.7 Medium relevance — show source text
E 503.5.7.7 Chilled-Water Coil Selection.

Chilled-water cooling coils shall be selected to provide a 15°F (8°C) or higher temperature difference between leaving and entering water temperatures and a minimum of 57°F (14°C) leaving water temperature at design conditions.

Exceptions:

(1) Chilled-water cooling coils that have an air-side pressure drop exceeding 0.70 inch of water (0.17 kPa) when rated at 500 feet per minute (2.54 m/s) face velocity and dry conditions (no condensation).

(2) Individual fan-cooling units with a design supply airflow rate 5000 cubic feet per minute (ft [3] /min) (2.36 m [3] /s) and less.

(3) Constant-air-volume systems.

(4) Coils selected at the maximum temperature difference allowed by the chiller.

(5) Passive coils (no mechanically supplied airflow).

(6) Coils with design entering chilled-water temperatures of 50°F (10°C) and higher.

(7) Coils with design entering air dry-bulb temperatures of 65°F (18°C) and lower. [ASHRAE 90.1:6.5.4.7]

E 503.5.8 Heat Rejection Equipment. Section E 503.5.8 through Section E 503.5.9 applies to heat-rejection equipment used in comfort cooling systems, such as air-cooled condensers, dry coolers, open-circuit cooling towers, closed-circuit cooling towers, and evaporative condensers.

»

»

»

(3) Water temperature reset is not required where valve position is used to comply with Section E 503.5.7. [ASHRAE 90.1:6.5.4.4]

E 503.5.7.5 Hydronic (Water Loop) Heat Pump and Water-Cooled Unitary Air Condi- tioners. Hydronic heat pumps and water-cooled unitary air-conditioners shall have a two-position automatic valve interlocked to shut off water flow

when the compressor is off.

Exception: Units employing fluid economizers.

[ASHRAE 90.1:6.5.4.5.1]

E 503.5.7.5.1 Controls. Hydronic heat pumps and water-cooled unitary air-conditioners having a total pump system power exceeding 5 hp (3.7 kW) shall have controls, devices, or both (such as variable speed control) that will result in pump motor demand of not more than 30 percent of design wattage at 50 percent of design water flow. [ASHRAE 90.1:6.5.4.5.2]

E 503.5.7.6 Pipe Sizing. Chilled-water and condenser-water piping shall be designed such that the design flow rate in each piping segment shall not exceed the values listed in Table E 503.5.7.6 for the

appropriate total annual hours of operation. Piping size selections for systems that operate under variable flow conditions (e.g., modulating two-way control valves at coils) and that contain variable-speed pump motors shall be permitted to be made from the “Variable Flow/Variable Speed” columns. All others shall be made from the “Other” columns.

Exceptions:

Frequently asked questions

Where in the CPC is the definitive color scheme for pipe labels?

The CPC itself references the industry standard ASME A13.1 for color and banding rules; use ASME A13.1 unless a CPC section or the AHJ requires a different scheme.

Does the CPC require factory (manufacturer) markings on every pipe length?

Yes — § 301.2.1 requires manufacturer-applied markings per the applicable referenced standard; field markings are not acceptable as a substitute.

Where does the CPC require labels/signage for reclaimed or gray water systems?

Chapter 15 contains the identification and signage requirements for alternate water sources; see § 1501.4 and § 1501.9.

Are there special labeling rules for medical gas piping?

Yes — Chapter 13 (medical gas and vacuum) contains required labeling and operating-pressure identification, e.g., § 1323.13 and related sections.

I can’t find § 310.11 and § 310.12 in the snippets — what should I do?

The retrieved files used here did not include the text for § 310.11 and § 310.12, so I cannot summarize or quote them. Look them up in the CPC volume or consult the Authority Having Jurisdiction for the exact language.

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