CPC · California Plumbing Code

Risk categories and overarching design requirements

Q: Who must assign the risk category for a given room or system?

The facility’s governing body must assign the risk category after establishing the planned processes and operations. § 1302.1.1 .

Q: Is a written risk assessment always required?

No — a documented risk assessment is not required when Category 1 is selected . For Categories 2–4, the governing body must follow and document a defined risk assessment procedure. § 1302.1.3 , § 1302.1.2 .

Q: Do these Category rules apply to existing systems?

The requirements apply to new construction and new equipment ; for existing systems, only the altered/renovated portions are required to meet the chapter’s installation/equipment requirements unless the AHJ determines a continued hazard. § 1301.4 , § 1301.5 .

For homeowners: health‑care plumbing and related medical systems must be designed to a risk Category (1–4) assigned by the facility’s governing body. If the work is more than minimal (not Category 1), the facility must perform and usually document a formal risk assessment; the local code official may ask to review it. The California Plumbing Code explains these duties in **§ 1302.0** and **§ 1302.1**.

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Last reviewed: July 6, 2026

What the code requires — plain English

All new or altered activities, systems, and equipment in health care facilities must be designed to meet one of four risk categories (Category 1–4) established for that facility. The facility’s governing body is responsible for establishing planned processes/operations, conducting a risk assessment to assign categories, and documenting that assessment when required; the Authority Having Jurisdiction (AHJ) may require submission of the assessment. See § 1302.0 and § 1302.1.

The most important rule: All new or altered plumbing-related systems or activities in a health‑care facility must be designed to the Category (1–4) assigned by the facility’s governing body, and that assignment must be based on a documented risk assessment except when Category 1 is selected. § 1302.0 / § 1302.1.3.

Definitions and first mentions:

Risk categories — the four ordered categories (Category 1, 2, 3, 4) used to scale design and performance requirements. § 1302.1.1.1.
Governing body — the facility authority charged with establishing processes, performing risk assessments, and assigning categories. § 1302.1.1.
Risk assessment — the defined procedure used to classify areas/processes; it must be documented except where Category 1 is selected. § 1302.1.2 / § 1302.1.3.

Requirements in detail

High‑level design obligation

All new or altered activities, systems, or equipment must be designed to meet the Category assigned by the governing body. § 1302.0.

Who decides and how

The facility’s governing body shall:
- Establish the planned processes and operations for the facility. § 1302.1.1.
- Conduct and document a risk assessment procedure to determine category assignments. § 1302.1.1.1, § 1302.1.2.
Where required by the AHJ, the documented risk assessment must be submitted for review. § 1302.1.2.1.

Documentation rule

A documented risk assessment is required for all categories except Category 1. If the governing body selects Category 1, no documented assessment is required by this provision. § 1302.1.3.

Patient care spaces

The governing body (or designee) shall establish the areas that correspond to each Category based on anticipated patient care (see patient care space definition in Chapter 2). § 1302.2.

Quick decision table (decision‑relevant values)

Decision item	Values / threshold	Who decides / acts	Code Reference
Applicability	New or altered activities/systems/equipment	Designer / Owner must apply Category rules	§ 1302.0
Category set	Category 1, 2, 3, 4	Governing body assigns based on processes/operations	§ 1302.1.1.1
Risk assessment required?	Yes for Categories 2–4; No documentation required when Category 1 is selected	Governing body performs; submit to AHJ when required	§ 1302.1.2, § 1302.1.3, § 1302.1.2.1
Process definition	Planned processes and operations for the facility	Governing body establishes	§ 1302.1.1
Patient care spaces	Areas established by governing body per anticipated patient care	Governing body / designee	§ 1302.2

Exceptions & special cases

The chapter’s procedural and equipment requirements do not supersede or conflict with NFPA 99 requirements; consult NFPA 99 where this chapter does not address a medical gas/vacuum topic. § 1301.3.
The design and equipment requirements in this chapter apply primarily to new construction and new equipment; existing systems are only required to meet updated requirements for the altered/renovated portion unless the AHJ finds continued use to be a distinct hazard. § 1301.4, § 1301.5.
Where the AHJ requires it, the governing body must provide the risk assessment for review (that is, AHJ submission is case‑by‑case per § 1302.1.2.1). If the AHJ does not require submission, retain the documented assessment in facility records. § 1302.1.2.1.

If you need a list of what kinds of processes typically map to each Category (for example: which clinical areas are normally Category 4 vs Category 2), the CPC text in the retrieved sections does not enumerate specific mappings — the governing body must determine categories using its risk assessment procedure. The Code text does not list numeric scoring or fixed mappings in § 1302.0 / § 1302.1.

Common mistakes

Assuming Category assignments are the AHJ’s job. The Code makes the governing body responsible for establishing processes and assigning categories; the AHJ reviews only when required. § 1302.1.1, § 1302.1.2.1.
Failing to document the risk assessment for anything other than Category 1. The requirement to document (and to retain/submit when required) applies except when Category 1 is chosen. § 1302.1.3.
Treating “new” and “altered” differently for applicability—both are covered: all activities/systems that are new or altered must be designed to the assigned Category. § 1302.0.
Not defining patient care spaces before assigning category‑specific design criteria. The governing body must establish patient care spaces in accordance with anticipated care. § 1302.2.

Worked example — applying the rule (concrete scenario)

Scenario: A 150‑bed acute care hospital plans to renovate one operating room (OR) and add a new intraoperative anesthesia machine and two wall vacuum outlets (an alteration to existing systems).

Step 1 — Establish processes: The hospital’s governing body documents that the OR is used for invasive surgery and anesthesia. (Governance requirement: § 1302.1.1.)

Step 2 — Perform risk assessment: The governing body follows its defined procedure and determines that the OR activities are not Category 1 (i.e., they involve critical invasive care). Because Category 1 is not selected, the governing body prepares a documented risk assessment describing why the OR is Classed (e.g., Category 3 or 4 depending on the facility’s criteria). (Documentation requirement: § 1302.1.2, § 1302.1.3.)

Step 3 — Design to the assigned Category: The design team sizes, locates, and specifies the anesthesia machine and vacuum outlets to meet the performance and installation requirements associated with the assigned Category in this chapter (the chapter outlines category‑based requirements elsewhere). § 1302.0.

Step 4 — AHJ submission: If the local AHJ requires review of the risk assessment for OR alterations, the hospital submits the documented assessment. (Submission clause: § 1302.1.2.1.)

Numeric clarity used: “1 OR renovated; 1 new anesthesia machine; 2 new vacuum outlets” — these counts affect design detail and testing but do not change the requirement that the facility assign a Category and document the assessment when Category 1 is not chosen. The CPC text does not prescribe a point score or numeric threshold for assigning Category 3 vs Category 4; that determination is the governing body’s risk assessment outcome.

Related provisions (quick pointer)

§ 1301.3 — Conflict of requirements with NFPA 99; consult NFPA 99 where this chapter doesn’t address medical gas/vacuum topics.
§ 1301.4 — Where construction/equipment requirements apply (new construction/new equipment).
§ 1301.5 — Existing systems: only altered/renovated portions required to meet new requirements unless AHJ finds hazard.
§ 1302.2 — Duties to establish patient care spaces in accordance with anticipated patient care.
See Chapter 2 definitions for patient care space (referenced by § 1302.2) — definitions and space classifications are in Chapter 2.

Code references

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

CPC § 1301.3 High relevance — show source text
(1) Cylinder and container management, storage, and reserve requirements

(2) Bulk supply systems

(3) Electrical connections and requirements

(4) Motor requirements and controls

(5) Systems having nonstandard operating pressures

(6) Waste anesthetic gas disposal (WAGD) systems

(7) Surface-mounted medical gas rail systems

(8) Breathing air replenishment (BAR) systems

(9) Portable compressed gas systems

(10)Medical support gas systems

(11)Gas-powered device supply systems

(12)Scavenging systems 1301.3 Conflict of Requirements. The requirements of this chapter shall not be interpreted to conflict with the requirements of NFPA 99. For requirements of portions of medical gas and vacuum systems not addressed in this chapter or medical gas and vacuum systems beyond the scope of this chapter refer to NFPA 99.

1301.4 Where Required. Construction and equipment requirements shall be applied only to new construction and new equipment, except as modified in individual sections of this chapter. {NFPA 99:1.3.2} 1301.5 Existing Systems. Only the altered, renovated, or modernized portion of an existing system or individual component shall be required to meet the installation and equipment requirements stated in this code. If the alteration, renovation, or modernization adversely impacts the existing performance requirements of a system or component, additional upgrading shall be required. An existing system that is not in strict compliance with the provisions of this code shall be permitted to be continued in use, unless the Authority Having Jurisdiction has determined that such use constitutes a distinct hazard to life. [NFPA 99:1.3.2.1 – 1.3.2.3]

1302.0 Design Requirements. 1302.1 Risk Categories. All activities, as well as systems or equipment that are new or altered, shall be designed to meet Category 1 through Category 4 requirements, as detailed in this chapter. {NFPA 99:4.1} 1302.1.1 Processes and Operations. The health care facility’s governing body shall establish the processes and operations that are planned for the health care facility. [NFPA 99:4.2.1] 1302.1.1.1 Risk Categories. The governing body shall conduct risk assessments and shall determine risk categories based on the character of the processes and operations conducted in the health care facility. [NFPA 99:4.2.1.1] 1302.1.2 Risk Assessment. Risk categories shall be classified by the health care facility’s governing body by following and documenting a defined risk assessment procedure. [NFPA 99:4.2.2] 1302.1.2.1 Documents to the Authority Hav- ing Jurisdiction. Where required by the Authority Having Jurisdiction (AHJ), the risk assessment shall be provided to the AHJ for review based on the character of the processes and operations conducted in the health care facility. [NFPA 99:4.2.2.1]

1302.1.3 Documented Risk Assessment. A documented risk assessment shall not be required where Category 1 is selected. [NFPA 99:4.2.3] 1302.2 Patient Care Spaces. The health care facility’s governing body or its designee shall establish the following areas in accordance with the type of patient care anticipated (see definition of patient care space in Chapter 2):

(1) Category 1 spaces

(2) Category 2 spaces
CPC § 1301.5 High relevance — show source text
TABLE OF CONTENTS

1301.5 Existing Systems . . . . . . . . . . . . .275

1302.0 Design Requirements . . . . . . . . . .275

1302.1 Risk Categories . . . . . . . . . . . . . .275

1302.2 Patient Care Spaces . . . . . . . . . .275

1302.3 Anesthesia . . . . . . . . . . . . . . . . . .275

1302.4 Wet Procedure Locations . . . . . . .275

1303.0 Health Care Facilities . . . . . . . . . .275

1303.1 Drinking Fountain Control Valves . . . . . . . . . . . . . . . . . . . . . .275

1303.2 Psychiatric Patient Rooms . . . . . .275

1303.3 Locations for Ice Storage . . . . . . .276

1303.4 Sterilizers and Bedpan Steamers . . . . . . . . . . . . . . . . . . .276

1303.5 Aspirators . . . . . . . . . . . . . . . . . . .276

1303.6 Drains . . . . . . . . . . . . . . . . . . . . . .276

1303.7 Clinical Sinks . . . . . . . . . . . . . . . .276

1303.8 Water Supply for Hospitals . . . . . .276

1303.9 Work Performed in Occupied Healthcare Facilities . . . . . . . . . . .276

1304.0 Medical Gas and Medical Vacuum Piping Systems . . . . . . .276

1304.1 General . . . . . . . . . . . . . . . . . . . . .276

1304.2 Certification of Systems . . . . . . . .276

1304.3 Construction Documents . . . . . . .276

1304.4 Extent of Work . . . . . . . . . . . . . . .276

1304.5 Record . . . . . . . . . . . . . . . . . . . . .276

1305.0 System Performance . . . . . . . . . .276

1305.1 Required Operating Pressures . . .276

Table 1305.1 Standard Designation Colors and Operating Pressures for Gas and Vacuum Systems . . . . . .277

1305.2 Minimum Flow Rates . . . . . . . . . .277

1305.3 Minimum Station Outlets

and Inlets . . . . . . . . . . . . . . . . . . .277

1306.0 System Certification . . . . . . . . . . .277

1306.1 Certification . . . . . . . . . . . . . . . . . .277

1306.2 Certification Tests . . . . . . . . . . . . .277

1306.3 Report Items . . . . . . . . . . . . . . . . .277

1306.4 Components . . . . . . . . . . . . . . . . .277

Table 1305.2 Minimum Flow Rates . . . . . . . . . .277

Table 1305.3 Minimum Outlets and Inlets

Per Station . . . . . . . . . . . . . . . . . .278

CPC § 16A-7 Medium relevance — show source text

Members that tend to accumulate residual deformations under repeated service loads shall have included in their analysis the effects of added deformations expected to occur during their service life.

Any system or method of construction to be used shall be based on a rational analysis in accordance with well-established principles of mechanics. Such analysis shall result in a system that provides a complete load path capable of transferring loads from their point of origin to the load-resisting elements.

The total lateral force shall be distributed to the various vertical elements of the lateral force-resisting system in proportion to their rigidities, considering the rigidity of the horizontal bracing system or diaphragm. Rigid elements assumed not to be a part of the lateral force-resisting system are permitted to be incorporated into buildings provided that their effect on the action of the system is considered and provided for in the design. Where a diaphragm is not permitted to be idealized as either flexible or rigid in accordance with ASCE 7 or for wood diaphragms in accordance with AWC SDPWS, the structure shall be analyzed and designed utilizing one of the following procedures:

An envelope analysis of the structure using a flexible and rigid diaphragm analysis separately and designing each component for the more severe load condition.
A semirigid diaphragm analysis and design.

Where required by ASCE 7, provisions shall be made for the increased forces induced on resisting elements of the structural system resulting from torsion due to eccentricity between the center of application of the lateral forces and the center of rigidity of the lateral force-resisting system.

2025 CALIFORNIA BUILDING CODE 16A-7

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STRUCTURAL DESIGN

Every structure shall be designed to resist the effects caused by the forces specified in this chapter, including overturning, uplift and sliding. Where sliding is used to isolate the elements, the effects of friction between sliding elements shall be included as a force.

1604 A .5 Risk category. Each building and structure shall be assigned a risk category in accordance with Table 1604 A .5. Where a referenced standard specifies an occupancy category, the risk category shall not be taken as lower than the occupancy category specified therein. Where a referenced standard specifies that the assignment of a risk category be in accordance with ASCE 7, Table 1.5-1, Table 1604 A .5 shall be used in lieu of ASCE 7, Table 1.5-1.

Exceptions:

The assignment of buildings and structures to Tsunami Risk Categories III and IV is permitted to be in accordance with Section 6.4 of ASCE 7.
Freestanding parking garages not used for the storage of emergency services vehicles or not providing means of egress for buildings or structures assigned to a higher risk category shall be assigned to Risk Category II.

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TABLE 1604A.5—RISK CATEGORY OF BUILDINGS AND OTHER STRUCTURES	Col2
RISK CATEGORY	NATURE OF OCCUPANCY
I	Buildings and other structures that represent a low hazard to human life in the event of failure, including but not limited to: • Agricultural facilities. • Certain temporary facilities. • Minor storage facilities.
II	Buildings and other structures except those listed in Risk Categories I, III and IV.
III	Buildings and other structures that represent a substantial hazard to human life in the event of failure,

CPC § 6.2. Medium relevance — show source text
Adjacent structures or site features that may affect the retrofit design shall be identified._

The entire load path of the seismic-force-resisting system shall be determined, documented and evaluated. The load path includes all the horizontal and vertical elements participating in the structural response: such as diaphragms, diaphragm chords, diaphragm collectors, vertical elements such as walls frames, braces; foundations and the connections between the components and elements of the load path. Repaired or retrofitted elements and the standards under which the work was constructed shall be identified.

Data collection in accordance with ASCE 41 shall meet the following minimum levels: 1. [BSC] For state-owned buildings, the requirements shall be met following the data collection requirements of ASCE 41, Section 6.2.

2. [DSA-SS, DSA-SS/CC] For public schools and community college buildings constructed in conformance with the Field Act, visual condition assessment and usual material testing is required unless a more extensive level is required by ASCE 41, Section 6.2.

3. [DSA-SS, DSA-SS/CC] For public schools and community college buildings not constructed in conformance with the Field Act, comprehensive condition assessment and material testing is required, unless a more extensive level is required by ASCE 41, Section 6.2.

Concrete material requirements and testing for public school and community college buildings shall also comply with Sections 1911A and 1909.5 of the California Building Code, respectively.

Qualified test data from the original construction may be accepted, in part or in whole, by the enforcement agency to fulfill the data collection requirements.

Exceptions: 1. The number of samples for data collection may be adjusted with approval of the enforcement agency when it has been determined that adequate information has been obtained or additional information is required. 2. Welded steel moment frame connections of buildings that may have experienced potentially damaging ground motions shall be inspected in accordance with Chapters 3 and 4, FEMA 352, Recommended Post Earthquake Evaluation and Repair Criteria for Welded Moment-Frame Construction for Seismic Applications (July 2000).

Where original building plans and specifications are not available, “as-built” plans shall be prepared that depict the existing vertical and lateral structural systems, exterior elements, foundations and nonstructural systems in sufficient detail to complete the design.

Data collection shall be directed and observed by the project structural engineer or design professional in charge of the design.

319.3 Site geology and soil characteristics. Soil profile shall be assigned in accordance with the requirements of Chapter 18 of the California Building Code.

319.4 Risk categories. Each structure shall be placed in one of the Risk Categories in accordance with the requirements of the California Building Code.

319.5 Configuration requirements. Each structure shall be designated structurally regular or irregular. If the evaluation and retrofit is in accordance with Table 317.5, Footnote 2 or 3, the building shall be classified by application of ASCE 7, Section 12.3.2. If the evaluation and retrofit is in accordance with ASCE 41, the building shall be classified as irregular when an irregularity defined in ASCE 41, Sections 7.3.1.1.1 through 7.3.1.1.4 exists.

319.6 General selection of the design method. The requirements of Method B (Section 321) may be used for any existing building.
CPC § 11.0 Medium relevance — show source text
11.0 - 1.11.11_|||X|||||||||||||||||||||| |1.13.0||||||||||||||||||||X||||| |Division II - Scope and
Administration||||||||||||||||||||||||| |101.0||||||||||X|X|X||X|X|||||||||| |102.0||||||||||X|X|X||X|X|||||||||| |103.0||||||||||X|X|X||X|X|||||||||| |104.2 Items 1 & 2||||X|X|||||||||||||||||||| |104.3.1||||||||||X|X|X||X|X|||||||||| |104.4.3.1|X|||||||||||||||||||||||| |105.0||||||||||X|X|X||X|X||||||||||

This state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.0.

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CHAPTER 1

ADMINISTRATION

DIVISION I

CALIFORNIA ADMINISTRATION

1.1.0 General.

1.1.1 Title. These regulations shall be known as the Califor- nia Plumbing Code, may be cited as such and will be referred to herein as “this code.” The California Plumbing Code is Part 5 of thirteen parts of the official compilation and publi- cation of the adoption, amendment, and repeal of plumbing regulations to the California Code of Regulations, Title 24, also referred to as the California Building Standards Code. This part incorporates by adoption the 2024 Uniform Plumb- ing Code of the International Association of Plumbing and Mechanical Officials with necessary California amendments.

1.1.2 Purpose. The purpose of this code is to establish the minimum requirements to safeguard the public health, safety and general welfare through structural strength, means of egress facilities, stability, access to persons with disabilities, sanitation, adequate lighting and ventilation, and energy con- servation; safety to life and property from fire and other haz- ards attributed to the built environment; and to provide safety to fire fighters and emergency responders during emergency operations.

1.1.3 Scope. The provisions of this code shall apply to the construction, alteration, movement, enlargement, replace- ment, repair, equipment, use and occupancy, location, main- tenance, removal, and demolition of every building or structure or any appurtenances connected or attached to such buildings or structures throughout the State of California.
CPC § 5.5 Medium relevance — show source text
5|5.5|5.5| |6|Dishwasher|1|0.5|1.3|1.3| |7|Kitchen Faucet|1|2.0|2.2|2.2| |8|Laundry Faucet|0|2.0|2.0|2.0| |9|Lavatory Faucet|1|2.0|1.5|1.5| |10|Shower, per head|0|4.5|2.0|2.0| |11|Water Closet, 1.28 GPF Gravity Tank|0|1.0|3.0|3.0| |12|Other Fixture 1|0|0.0|0.0|6.0| |13|Other Fixture 2|0|0.0|0.0|6.0| |14|Other Fixture 3|0|0.0|0.0|6.0| |Total Number of Fixtures|Total Number of Fixtures|5||RESET|RUN WATER DEMAND
CALCULATOR| |99th Percentile Demand Flow =|99th Percentile Demand Flow =|7.7 GPM||||

For SI units: 1 gallon per minute = 0.66 L/s, 1 gallon = 3.785 L

FIGURE 5 WATER DEMAND CALCULATOR FOR THE HOT WATER BRANCH (EXAMPLE 4)

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CALIFORNIA PLUMBING CODE – MATRIX ADOPTION TABLE

APPENDIX N - IMPACT OF WATER TEMPERATURE ON THE POTENTIAL FOR SCALDING AND LEGIONELLA GROWTH

(Matrix Adoption Tables are non-regulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)
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|

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Uniform Plumbing Code – 2024 Edition:

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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.

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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!

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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.

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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 § 2.0 Medium relevance — show source text

2| |8|Laundry Faucet|0|2.0|2.0|2.0| |9|Lavatory Faucet|1|2.0|1.5|1.5| |10|Shower, per head|0|4.5|2.0|2.0| |11|Water Closet, 1.28 GPF Gravity Tank|0|1.0|3.0|3.0| |12|Other Fixture 1|0|0.0|0.0|6.0| |13|Other Fixture 2|0|0.0|0.0|6.0| |14|Other Fixture 3|0|0.0|0.0|6.0| |Total Number of Fixtures|Total Number of Fixtures|5||RESET|RUN WATER DEMAND
CALCULATOR| |99th Percentile Demand Flow =|99th Percentile Demand Flow =|7.7 GPM||||

For SI units: 1 gallon per minute = 0.66 L/s, 1 gallon = 3.785 L

FIGURE 5 WATER DEMAND CALCULATOR FOR THE HOT WATER BRANCH (EXAMPLE 4)

524 2025 CALIFORNIA PLUMBING CODE

CALIFORNIA PLUMBING CODE – MATRIX ADOPTION TABLE

APPENDIX N - IMPACT OF WATER TEMPERATURE ON THE POTENTIAL FOR SCALDING AND LEGIONELLA GROWTH

(Matrix Adoption Tables are non-regulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)

Adopting Agency	BSC	BSC- CG	SFM	HCD	Col6	Col7	DSA	Col9	Col10	OSHPD	Col12	Col13	Col14	Col15	Col16	Col17	BSCC	DPH	AGR	DWR	CEC	CA	SL	SLC
Adopting Agency	BSC	BSC- CG	SFM	1	2	1-AC	AC	SS	SS/CC	1	1R	2	3	4	5	6	6	6	6	6	6	6	6	6
Adopt Entire Chapter								X		X	X	X	X	X	X	X
Adopt Entire Chapter as amended (amended sections listed below)
Adopt only those sections that are listed below
Chapter/Section

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.|
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IS 33

FIGURE 1

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

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IS 33

FIGURE 2

THRUST BLOCK BEARING AREA (See Section 5.2.2)

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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 § 2.0 Medium relevance — show source text

When there is only one fixture or appliance served by a fixture branch, the demand flow shall not exceed the fixture flow rate in Column [E] of the Water Demand Calculator. The fixture flow rate would be used in Step 2 to determine the size of the fixture branch and supply.

[A] FIXTURE	Col2	[B] ENTER NUMBER OF FIXTURES	[C] PROBABILITY OF USE (%)	[D] ENTER FIXTURE FLOW RATE (GPM)	[E] MAXIMUM RECOMMENDED FIX- TURE FLOW RATE (GPM)
1	Bar Sink	0	2.0	1.5	1.5
2	Bathtub	0	1.0	5.5	5.5
3	Bidet	0	1.0	2.0	2.0
4	Clothes Washer	1	5.5	3.5	3.5
5	Combination Bath/Shower	1	5.5	5.5	5.5
6	Dishwasher	1	0.5	1.3	1.3
7	Kitchen Faucet	1	2.0	2.2	2.2
8	Laundry Faucet	0	2.0	2.0	2.0
9	Lavatory Faucet	1	2.0	1.5	1.5
10	Shower, per head	0	4.5	2.0	2.0
11	Water Closet, 1.28 GPF Gravity Tank	1	1.0	3.0	3.0
12	Pot Filler	1	2.0	5.5	6.0
13	Dog Bath	1	1.0	5.5	6.0
14	Other Fixture 3	0	0.0	0.0	6.0
Total Number of Fixtures	Total Number of Fixtures	8		RESET	RUN WATER DEMAND CALCULATOR
99th Percentile Demand Flow =	99th Percentile Demand Flow =	11.0 GPM

For SI units: 1 gallon per minute = 0.66 L/s, 1 gallon = 3.785 L

FIGURE 4 WATER DEMAND CALCULATOR TO ACCOMMODATE OTHER FIXTURES (EXAMPLE 3)

2025 CALIFORNIA PLUMBING CODE 523

APPENDIX M

[A] FIXTURE	Col2	[B] ENTER NUMBER OF FIXTURES	[C] PROBABILITY OF USE (%)	[D] ENTER FIXTURE FLOW RATE (GPM)	[E] MAXIMUM RECOMMENDED FIX- TURE FLOW RATE (GPM)
1	Bar Sink	0	2.0	1.5	1.5
2	Bathtub	0	1.0	5.5	5.5
3	Bidet	0	1.0	2.0	2.0
4	Clothes Washer	1	5.5	3.5	3.

CPC § 2.0 Medium relevance — show source text

0| |12|Pot Filler|1|2.0|5.5|6.0| |13|Dog Bath|1|1.0|5.5|6.0| |14|Other Fixture 3|0|0.0|0.0|6.0| |Total Number of Fixtures|Total Number of Fixtures|8||RESET|RUN WATER DEMAND
CALCULATOR| |99th Percentile Demand Flow =|99th Percentile Demand Flow =|11.0 GPM||||

For SI units: 1 gallon per minute = 0.66 L/s, 1 gallon = 3.785 L

FIGURE 4 WATER DEMAND CALCULATOR TO ACCOMMODATE OTHER FIXTURES (EXAMPLE 3)

2025 CALIFORNIA PLUMBING CODE 523

APPENDIX M

[A] FIXTURE	Col2	[B] ENTER NUMBER OF FIXTURES	[C] PROBABILITY OF USE (%)	[D] ENTER FIXTURE FLOW RATE (GPM)	[E] MAXIMUM RECOMMENDED FIX- TURE FLOW RATE (GPM)
1	Bar Sink	0	2.0	1.5	1.5
2	Bathtub	0	1.0	5.5	5.5
3	Bidet	0	1.0	2.0	2.0
4	Clothes Washer	1	5.5	3.5	3.5
5	Combination Bath/Shower	1	5.5	5.5	5.5
6	Dishwasher	1	0.5	1.3	1.3
7	Kitchen Faucet	1	2.0	2.2	2.2
8	Laundry Faucet	0	2.0	2.0	2.0
9	Lavatory Faucet	1	2.0	1.5	1.5
10	Shower, per head	0	4.5	2.0	2.0
11	Water Closet, 1.28 GPF Gravity Tank	0	1.0	3.0	3.0
12	Other Fixture 1	0	0.0	0.0	6.0
13	Other Fixture 2	0	0.0	0.0	6.0
14	Other Fixture 3	0	0.0	0.0	6.0
Total Number of Fixtures	Total Number of Fixtures	5		RESET	RUN WATER DEMAND CALCULATOR
99th Percentile Demand Flow =	99th Percentile Demand Flow =	7.7 GPM

For SI units: 1 gallon per minute = 0.66 L/s, 1 gallon = 3.785 L

FIGURE 5 WATER DEMAND CALCULATOR FOR THE HOT WATER BRANCH (EXAMPLE 4)

524 2025 CALIFORNIA PLUMBING CODE

CALIFORNIA PLUMBING CODE – MATRIX ADOPTION TABLE

CPC § 0.453 Medium relevance — show source text

For SI units: 1 inch = 25 mm, 1 pound = 0.453 kg, 1 ounce = 0.02834 kg

TABLE 701.7

SOLDERING BUSHINGS

PIPE SIZE (inches)	MINIMUM WEIGHT EACH	Col3	PIPE SIZE (inches)	MINIMUM WEIGHT EACH	Col6
PIPE SIZE (inches)	pounds	ounces	ounces	pounds	ounces
11⁄4	0	6	21⁄2	1	6
11⁄2	0	8	3	2	0
2	0	14	4	3	8

For SI units: 1 inch = 25 mm, 1 pound = 0.453 kg, 1 ounce = 0.02834 kg

702.0 Fixture Unit Equivalents. 702.1 Trap Size. The unit equivalent of plumbing fixtures shown in Table 702.1 shall be based on the size of the trap

TABLE 701.6

CAULKING FERRULES

For SI units: 1 inch = 25 mm, 1 pound = 0.453 kg, 1 ounce = 0.02834 kg

TABLE 701.7

SOLDERING BUSHINGS

For SI units: 1 inch = 25 mm, 1 pound = 0.453 kg, 1 ounce = 0.02834 kg

2025 CALIFORNIA PLUMBING CODE 165

SANITARY DRAINAGE

TABLE 701.2 MATERIALS FOR DRAIN, WASTE, VENT PIPE AND FITTINGS

MATERIAL	UNDERGROUND DRAIN, WASTE, VENT PIPE AND FITTINGS	ABOVEGROUND DRAIN, WASTE, VENT PIPE AND FITTINGS	BUILDING SEWER PIPE AND FITTINGS	REFERENCED STAN- DARD(S) PIPE	REFERENCED STANDARD(S) FITTINGS
ABS (Schedule 40)	X	X	X	ASTM D2661, ASTM D2680*	ASME A112.4.4, ASTM D2661, ASTM D2680*
Cast-Iron	X	X	X	ASTM A74, ASTM A888, CISPI 301	ASME B16.12, ASTM A74, ASTM A888, CISPI 301
Co-Extruded ABS (Schedule 40)	X	X	X	ASTM F628	ASME A112.4.4, ASTM D2661, ASTM D2680*
Co-Extruded Composite (Schedule 40)	X	X	X	ASTM F1488	ASME A112.4.4, ASTM D2661, ASTM D2665, ASTM F794*, ASTM F1866
Co-Extruded PVC (Schedule 40)	X	X	X	ASTM F891,

Frequently asked questions

Who must assign the risk category for a given room or system?

The facility’s governing body must assign the risk category after establishing the planned processes and operations. § 1302.1.1.

Is a written risk assessment always required?

No — a documented risk assessment is not required when Category 1 is selected. For Categories 2–4, the governing body must follow and document a defined risk assessment procedure. § 1302.1.3, § 1302.1.2.

Does the AHJ always get the risk assessment?

Only “where required by the AHJ” must the risk assessment be submitted for review; otherwise the governing body retains it. § 1302.1.2.1.

Do these Category rules apply to existing systems?

The requirements apply to new construction and new equipment; for existing systems, only the altered/renovated portions are required to meet the chapter’s installation/equipment requirements unless the AHJ determines a continued hazard. § 1301.4, § 1301.5.

Where can I find what activities belong to each Category?

The CPC sections retrieved (1302.0 / 1302.1) require the governing body to perform a risk assessment to assign categories; they do not list fixed mappings of specific activities to Categories. The governing body’s documented procedure is used to make that assignment. § 1302.1.1.1, § 1302.1.2.

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