Materials, Valves, Installation and Equipment

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

• CPC § 507.3 High relevance — show source text

  507.3 Appliance Support . . . . . . . . . . . . .88

  507.4 Ground Support . . . . . . . . . . . . . . .88

  507.5 Drainage Pan . . . . . . . . . . . . . . . . .88

  507.6 Added or Converted

  Equipment or Appliances . . . . . . . .88

  507.7 Type of Gas(es) . . . . . . . . . . . . . . .88

  507.8 Safety Shutoff Devices for Unlisted LP-Gas Appliance Used Indoors . . . . . . . . . . . . . . . . .89

  507.9 Use of Air or Oxygen Under Pressure . . . . . . . . . . . . . . . . . . . . .89

  507.10 Protection of Gas Appliances from Fumes or Gases other

  than Products of Combustion . . . . .89

  507.11 Process Air . . . . . . . . . . . . . . . . . . .89

  507.12 Flammable Vapors . . . . . . . . . . . . .89

  507.13 Installation in Residential Garages . . . . . . . . . . . . . . . . . . . . .89

  507.14 Installation in Commercial Garages . . . . . . . . . . . . . . . . . . . . .89

  507.15 Installation in Aircraft Hangars . . . .89

  507.16 Venting of Flue Gases . . . . . . . . . .89

  507.17 Extra Device or Attachment . . . . . .89

  507.18 Addition to Existing System . . . . . .89

  507.19 Avoiding Strain on Gas Piping . . . .89

  507.20 Gas Appliance Pressure Regulators . . . . . . . . . . . . . . . . . . .89

  507.21 Bleed Lines for Diaphragm-Type Valves . . . . . . . . . . . . . . . . . . . . . . .89

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  TABLE OF CONTENTS

  507.22 Combination of Appliances and Equipment . . . . . . . . . . . . . . . .90

  507.23 Installation Instructions . . . . . . . . . .90

  507.24 Protection of Outdoor

  Appliances . . . . . . . . . . . . . . . . . . .90

  507.25 Accessibility for Service . . . . . . . . .90

  507.26 Clearance to Combustible

  Materials . . . . . . . . . . . . . . . . . . . . .90

  508.0 Appliances on Roofs, in Attics or Under-Floor Spaces . . . . . . . . . .90

  508.1 General . . . . . . . . . . . . . . . . . . . . . .90

  508.2 Installation of Appliances on Roofs . . . . . . . . . . . . . . . . . . . . .90

  508.3 Appliances on Roofs . . . . . . . . . . .90

  508.4 Appliances in Attics and Under-Floor Spaces . . . . . . . . . . . .91

• CPC § 608.3 High relevance — show source text

  The expansion tank shall be properly sized, securely fastened to the structure, and installed in accordance with the manufacturer’s installation instructions and listing. Systems designed by a licensed plumbing contractor or registered design professionals shall be permitted to use approved pressure relief valves in lieu of expansion tanks provided such relief valves have a maximum pressure relief setting of 100 psi (689 kPa) or less. 608.3 Expansion Tanks, and Combination Tempera- ture and Pressure-Relief Valves. A water system provided with a check valve, backflow preventer, or other normally closed device that prevents dissipation of building pressure back into the water main, independent of the type of water heater used, shall be provided with an approved, listed, and adequately sized expansion tank or other approved device having a similar function to control thermal expansion. Prepressurized water expansion tanks shall comply with IAPMO/ANSI Z1088. Such expansion tank or other approved device shall be installed on the building side of the check valve, backflow preventer, or other device and shall be sized, securely fastened to the structure, and installed in accordance with the manufacturer’s installation instructions.

  A water system containing storage water heating equipment shall be provided with an approved, listed, adequately sized combination temperature and pressure-relief valve, except for listed nonstorage instantaneous heaters having an inside diameter of not more than 3 inches (80 mm). Each such approved combination temperature and pressure-relief valve shall be installed on the water-heating device in an approved location based on its listing requirements and the manufacturer’s installation instructions. Each such combination temperature and pressure-relief valve shall be provided with a drain in accordance with Section 608.5.

  Exception: An expansion tank shall not be required for an instantaneous non-storage water heater. 608.4 Pressure Relief Valves. Each pressure relief valve shall be an approved automatic type with drain, and each such relief valve shall be set at a pressure of not more than 150 psi (1034 kPa). No shutoff valve shall be installed between the relief valve and the system. 608.5 Discharge Piping. The discharge piping serving a temperature relief valve, pressure relief valve, or combination of both shall have no valves, obstructions, or means of isolation and be provided with the following:

  (1) Not less than the size of the valve outlet and shall discharge full size to the flood level of the area receiving the discharge and pointing down.

  (2) Materials shall be rated at not less than the operating temperature of the system and approved for such use or shall comply with ASME A112.4.1.

  (3) Discharge pipe shall discharge independently by gravity through an air gap into the drainage system or outside of the building with the end of the pipe not exceeding 2 feet

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  WATER SUPPLY AND DISTRIBUTION

  (610 mm) and not less than 6 inches (152 mm) above the ground and pointing downwards.

  (4) Discharge in such a manner that does not cause personal injury or structural damage. (5) No part of such discharge pipe shall be trapped or subject to freezing. (6) The terminal end of the pipe shall not be threaded. (7) Discharge from a relief valve into a water heater pan shall be prohibited. (8) The discharge termination point shall be readily observable.

• CPC § 710.5 High relevance — show source text

  Gate or ball valves, where installed in drainage piping, shall be fullway type with working parts of corrosion-resistant metal. Sizes 4 inches (100 mm) or more in diameter shall have cast-iron bodies and sizes less than 4 inches (100 mm), cast-iron or copper alloy bodies. 710.5 Size of Building Drains and Sewers. Building drains or building sewers receiving a discharge from a pump or ejector shall be adequately sized to prevent overloading. Two fixture units shall be allowed for each gallon per minute (L/s) of flow. 710.6 Backwater Valves. Backwater valves, gate valves, fullway ball valves, unions, motors, compressors, air tanks, and other mechanical devices required by this section shall be located where they will be accessible for inspection and repair and, unless continuously exposed, shall be enclosed in a masonry pit fitted with an adequately sized removable

  cover.

  Backwater valves shall comply with ASME A112.14.1 or IAPMO IGC 305, and have bodies of cast-iron, plastic, copper alloy, or other approved materials; shall have noncorrosive bearings, seats, and self-aligning discs; and shall be constructed to ensure a positive mechanical seal. Such backwater valves shall remain open during periods of low flows to avoid screening of solids and shall not restrict capacities or cause excessive turbulence during peak loads. Unless otherwise listed, valve access covers shall be bolted type with gasket, and each valve shall bear the manufacturer’s name cast into the body and the cover. 710.7 Drainage and Venting Systems. The drainage and venting systems, in connection with fixtures, sumps, receiving tanks, and mechanical waste-lifting devices shall be installed under the same requirements as provided for in this code for gravity systems. 710.8 Sump and Receiving Tank Construction. Sumps and receiving tanks shall be watertight and shall be constructed of concrete, metal, or other approved materials. Where constructed of poured concrete, the walls and bottom shall be adequately reinforced and designed to recognized acceptable standards. Metal sumps or tanks shall be of such

  thickness as to serve their intended purpose and shall be treated internally and externally to resist corrosion.

  710.9 Alarm. Such sumps and receiving tanks shall be automatically discharged and, wherein a “public use” occupancy, shall be provided with dual pumps or ejectors arranged to function alternately in normal use and independently. Such pumps shall be capable of running continuously in case of overload or mechanical failure of one of the pumps or ejectors. The pumps shall have an audio and visual alarm, readily accessible, that signals pump failure or an overload condition. The lowest inlet shall have a clearance of not less than 2 inches (51 mm) from the high-water or “starting” level of the sump. 710.10 Sump and Receiving Tank Covers and Vents. Sumps and receiving tanks shall be provided with substantial covers having a bolt-and-gasket-type manhole or equivalent opening to permit access for inspection, repairs, and cleaning. The top shall be provided with a vent pipe that shall extend separately through the roof or, where permitted, be combined with other vent pipes. Such vent shall be large enough to maintain atmospheric pressure within the sump under normal operating conditions and, in no case, shall be less in size than that required by Table 703.2 for the number and type of fixtures discharging into the sump, nor less than 1 [1] ⁄ 2 inches (40 mm) in diameter.

• CPC § 603.5.17 High relevance — show source text

  603.5.17 Potable Water Outlets and Valves. Potable water outlets, freeze-proof yard hydrants, combination stop-and-waste valves, or other fixtures that incorporate a stop and waste feature that drains into the ground shall not be installed underground. 603.5.18 Pure Water Process Systems. The water supply to a pure water process system, such as dialysis water systems, semiconductor washing systems, and similar process piping systems, shall be protected from backpressure and backsiphonage by a reduced-pressure principle backflow preventer. 603.5.18.1 Dialysis Water Systems. The individual connections of the dialysis related equipment to the dialysis pure water system shall not require additional backflow protection. 603.5.19 Garbage Can Washers. Where garbage can washers are connected to a potable water supply system, the connection shall be protected against backflow in accordance with Table 603.2.

  603.5.20 Plumbing Fixture Fittings. Plumbing fixture fittings with integral backflow protection shall comply with ASME A112.18.1/CSA B125.1. 603.5.21 Swimming Pools, Spas, and Hot Tubs. Potable water supply to swimming pools, spas, and hot tubs shall be protected by an air gap or a reduced pressure principle backflow preventer in accordance with the following:

  (1) The unit is equipped with a submerged fill line.

  (2) The potable water supply is directly connected to the unit circulation system. 603.5.22 Chemical Dispensers. The water supply to chemical dispensers shall be protected against backflow by one of the following:

  (1) The chemical dispenser shall comply with ANSI/CAN/ASSE/IAPMO 1055. Where an installation involves a water source coming from a faucet with an integrated vacuum breaker device, a pressure bleed device conforming to IAPMO PS 104 shall be used to protect the vacuum breaker device.

  (2) Water supply shall be protected by one of the following methods:

  (a) Air gap

  (b) Atmospheric vacuum breaker (AVB)

  (c) Pressure vacuum breaker backflow prevention assembly (PVB)

  (d) Spill-resistant pressure vacuum breaker (SVB)

  (e) Reduced-pressure principle backflow prevention assembly (RP)

  «

  «

  «

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  WATER SUPPLY AND DISTRIBUTION

  604.0 Materials.

  604.1 Pipe, Tube, and Fittings. Pipe, tube, fittings, solvent cement, thread sealants, solders, and flux used in potable water systems intended to supply drinking water shall comply with NSF/ANSI/CAN 61. Where pipe fittings and valves are made from copper alloys containing more than 15 percent zinc by weight and are used in plastic piping systems, they shall be resistant to dezincification and stress corrosion cracking in compliance with NSF/ANSI 14.

  Materials used in the water supply system, except valves and similar devices, shall be of a like material, except where otherwise approved by the Authority Having Jurisdiction.

  Materials for building water piping and building supply piping shall comply with the applicable standards referenced in Table 604.1.

• CPC § 4.1. High relevance — show source text

  (1) Not less than the size of the valve outlet and shall discharge full size to the flood level of the area receiving the discharge and pointing down.

  (2) Materials shall be rated at not less than the operating temperature of the system and approved for such use or shall comply with ASME A112.4.1.

  (3) Discharge pipe shall discharge independently by gravity through an air gap into the drainage system or outside of the building with the end of the pipe not exceeding 2 feet

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  WATER SUPPLY AND DISTRIBUTION

  (610 mm) and not less than 6 inches (152 mm) above the ground and pointing downwards.

  (4) Discharge in such a manner that does not cause personal injury or structural damage. (5) No part of such discharge pipe shall be trapped or subject to freezing. (6) The terminal end of the pipe shall not be threaded. (7) Discharge from a relief valve into a water heater pan shall be prohibited. (8) The discharge termination point shall be readily observable.

  608.6 Water-Heating Devices. A water-heating device connected to a separate storage tank and having valves between said heater and tank shall be provided with an approved water pressure relief valve. 608.7 Vacuum Relief Valves. Where a hot-water storage tank or an indirect water heater is located at an elevation above the fixture outlets in the hot-water system, a vacuum relief valve that complies with ANSI Z21.22/CSA 4.4 shall be installed on the storage tank or heater.

  609.0 Installation, Testing, Unions, and Location. 609.1 Installation. Water piping shall be adequately supported in accordance with Table 313.3. Burred ends shall be reamed to the full bore of the pipe or tube. Changes in direction shall be made by the appropriate use of fittings, except that changes in direction in copper or copper alloy tubing shall be permitted to be made with bends, provided that such bends are made with bending equipment that does not deform or create a loss in the cross-sectional area of the tubing. Changes in direction are allowed with flexible pipe and tubing without fittings in accordance with the manufacturer’s instructions. Provisions shall be made for expansion in hotwater piping. Piping, equipment, appurtenances, and devices shall be installed in a workmanlike manner in accordance with the provisions and intent of the code. Building supply yard piping shall be not less than 12 inches (305 mm) below the average local frost depth. The cover shall be not less than 12 inches (305 mm) below finish grade. 609.2 Trenches. Water pipes shall not be run or laid in the same trench as building sewer or drainage piping con structed of clay or materials that are not approved for use within a building unless both of the following conditions are met: (1) The bottom of the water pipe shall be not less than 12 inches (305 mm) above the top of the sewer or drain line. (2) The water pipe shall be placed on a solid shelf excavated at one side of the common trench with a clear horizontal distance of not less than 12 inches (305 mm) from the sewer or drain line.

• CPC § 31-2022 High relevance — show source text

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  "The information contained in this appendix is not part of this American National Standard (ANS) and has not been processed in accordance with ANSI's requirements for an ANS. As such, this appendix may contain material that has not been subjected to public review or a consensus process. In addition, it does not contain requirements necessary for conformance to the standard."

  The following IAPMO Installation Standard is included here for the convenience of the users of the Uniform Plumbing Code. It is not considered as a part of the Uniform Plumbing Code unless formally adopted as such. This Installation Standard is an independent, stand-alone document published by the International Association of Plumbing and Mechanical Officials and is printed herein by the expressed written permission of IAPMO.

  INSTALLATION STANDARD FOR PEX TUBING SYSTEMS

  FOR HOT- AND COLD-WATER DISTRIBUTION

  IAPMO IS 31-2022

  The provisions contained in this appendix are not mandatory unless specifically adopted by a state agency, or referenced in the adopting ordinance.

  1 Scope

  1.1 General

  1.1.1 This Standard specifies requirements for the installation of SDR 9 CTS crosslinked polyethylene (PEX) tubing and fittings, including cold-expansion, crimp, press, and mechanical compression fittings, intended for hot- and cold-water distribution systems within buildings.

  1.1.2 This Standards applies to

  (a) SDR 9 CTS PEX tubing complying with ASTM F876 and pressure-rated in accordance with PPI TR-3; and (b) PEX fitting systems complying with (i) ASTM F877, for mechanical compression fittings and metal or plastic insert fittings with stainless steel press sleeves; (ii) ASTM F1807 or ASTM F2159, for metal or plastic insert fittings with copper crimp rings; (iii) ASTM F1960, for cold expansion fittings with PEX reinforced rings; or (iv) ASTM F2080, for cold expansion fittings with metal compression sleeves. 1.2 Terminology

  In this Standard,

  (a) “shall” is used to express a requirement, i.e., a provision that the user is obliged to satisfy to comply with the Standard; (b) “should” is used to express a recommendation, but not a requirement; (c) “may” is used to express an option or something permissible within the scope of the Standard; and (d) “can” is used to express a possibility or a capability. Notes accompanying sections of the Standard do not specify requirements or alternative requirements; their purpose is to separate explanatory or informa

  tive material from the text. Notes to tables and figures are considered part of the table or figure and can be written as requirements.

  1.3 Units of Measurement

  SI units are the primary units of record in global commerce. In this Standard, the inch/pound units are shown in parentheses. The values stated in each measurement system are equivalent in application, but each unit system is to be used independently. All references to gallons are to U.S. gallons.

  2 Reference Publications

• CPC § 1501.7 High relevance — show source text

  Residential,
  and Commercial Use|Water Quality|1501.7, 1506.8,
  1506.10.2, 1603.4| |IAPMO IGC 325-2016|Oil/Water Separators Performance|Interceptors|Table 1009.1| |IAPMO PS 53-2020|Grooved Mechanical Pipe Couplings and Grooved Fittings|Fittings|Table 604.1| |IAPMO PS 65-2019a|Airgap Units for Water Conditioning Equipment Installation|Backflow Protection|611.2| |IAPMO PS 66-2015|Dielectric Fittings|Fittings|605.15, 605.16.1,
  605.16.3| |IAPMO PS 72-2019|Valves with Atmospheric Vacuum Breakers|Valves|603.5.6(5)| |IAPMO PS 76-2021|Trap Primers for Fill Valves and Flushometer Valves|DWV Components|1007.2| |IAPMO PS 80-2019|Clarifiers|Interceptors|Table 1009.1| |IAPMO PS 90-2014|Elastomeric Test Caps, Cleanout Caps, and Combination Test
  Caps/Shielded Couplings|DWV Components|Table 707.2| |IAPMO PS 104-2019|Pressure Relief Connection for Dispensing Equipment|Valves|603.5.22(1)| |IAPMO PS 106-2015el|Tileable Shower Receptors and Shower Kits|Fixtures|408.2| |IAPMO PS 117-2021|Press Connections|Fittings|Table 604.1| |CSA B45.5-2017/IAPMO
  Z124-2017|Plastic Plumbing Fixtures (with Errata dated August 2017)|Fixtures|407.1, 408.1, 409.1,
  411.1, 412.1, 420.1| |IAPMO/ANSI Z124.5-
  2013e1 (R2018)|Plastic Toilet Seats|Appurtenance|411.3| |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| |CSA B45.8-2018/IAPMO
  Z403-2018|Terrazzo, Concrete, Composite Stone, and Natural Stone
  Plumbing Fixtures|Fixtures|407.1, 420.1|

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  REFERENCED STANDARDS

  TABLE 1701.1 (continued) REFERENCED STANDARDS

  STANDARD NUMBER	STANDARD TITLE	APPLICATION	REFERENCED SECTION
  IAPMO/ANSI Z601-2018	Scale Reduction Devices	Water Conditioning, Water Treatment	611.1.2
  ANSI/CAN/IAPMO Z1001- 2021	Prefabricated Gravity Grease Interceptors	Fixtures	Table 1009.1, 1014.1,

• CPC § 601.1 High relevance — show source text

  601.1 Applicability. This chapter shall govern the materials, design, and installation of water supply systems, including methods and devices used for backflow prevention. 601.2 Water Supply and Flushing. Each plumbing fixture shall be provided with an adequate supply of potable running water piped thereto in an approved manner, so arranged as to flush and keep it in a clean and sanitary condition without danger of backflow or cross-connection. Water closets and urinals shall be flushed using an approved flush tank or flushometer valve.

  Exceptions:

  (1) Listed fixtures that do not require water for their operation and are not connected to the water supply.

  (2) Where not deemed necessary for safety and sanitation by the Authority Having Jurisdiction. (3) [HCD 1 & HCD 2] For limited-density owner-built rural dwellings, potable water shall be available to the dwelling site, although such water need not be pressur- ized. Where water is not piped from a well, spring, cistern or other source, there shall be a minimum reserve of 50 gallons (189 L) of potable water available. Where water delivery is pressurized, piping shall be installed in accor- dance with the provisions of this chapter. (4) [HCD 1, HCD 2 & DWR] For all residential occupan- cies, alternate water sources may be allowed as speci- fied in Chapter 15 of this code in addition to potable

  water.

  (5) [BSC-CG & DWR] For non-residential occupancies, alternate water sources may be allowed as specified in Chapter 15 of this code.

  (6) [DWR] Where a public agency requires a building to use recycled water to flush water closets and urinals in accordance with California Water Code 13554. 601.2.1 Submeters. [HCD 1] Submeters (or meters) shall be installed to measure potable and reclaimed (recycled) water (hot and cold) that is supplied for the exclusive use of an individual dwelling unit within a newly constructed, multiunit rental residential structure; or for the use of an individual dwelling unit within a newly constructed mixed-use rental residential/commer- cial structure. Submeters (or meters) shall be installed in accordance with this code and the manufacturer’s installation instructions.

  See Water Code Section 517 for definitions of “multiunit residential structure” and “mixed-use resi-

  dential and commercial structure.” See also Civil Code commencing with Section 1954.201.

  Exemptions:

  (1) Long-term health care facilities as defined in Health and Safety Code Section 1418.

  (2) Low-income housing as defined in Health and Safety Code Section 17922.14 (c)(2)(B).

  (3) Residential care facilities for the elderly as defined in Health and Safety Code Section 1569.2 (p)(1).

  (4) Housing at a place of education as defined in Title 24 of the California Code of Regulations, Califor- nia Building Code, Part 2, Section 202.

  (5) Time-share property as defined in Business and Pro- fessions Code Section 11212, Subdivision (aa).

• CPC § 312.0 Medium relevance — show source text

  312.0 Protection of Piping, Materials, and Structures

  314.0 Trenching, Excavation, and Backfill

  701.3 Drainage Fittings

  705.5.1.1 Butt Fusion Joints

  705.5.1.2 Electro-Fusion Joints

  705.5.1.3 Socket-Fusion Joints

  723.0 Building Sewer Test

  TABLE 1

  CLEANOUTS (See Section 4.6.1)

  The following standards from Tables 1701.1 and 1701.2 of the 2024 Uniform Plumbing Code apply.

  Table 1701.1 Standards

  ASTM D2239 Polyethylene (PE) Plastic Pipe (SIDRPR) Based on Controlled Inside Diameter

  ASTM D2683 Socket-Type Polyethylene Fittings for Outside Diameter-Controlled Polyethylene Pipe and Tubing

  ASTM D3261 Butt Heat Fusion Polyethylene (PE) Plastic Fittings for Polyethylene (PE) Plastic Pipe and Tubing

  ASTM F714 Polyethylene (PE) Plastic Pipe (DRPR) Based on Outside Diameter

  ASTM F894 Polyethylene (PE) Large Diameter Profile Wall Sewer and Drain Pipe

  ASTM F1055 Electrofusion Type Polyethylene Fittings for Outside Diameter Controlled Polyethylene and Crosslinked Polyethylene (PEX) Pipe and Tubing

  ASTM F2620 Heat Fusion Joining of Polyethylene Pipe and Fittings

  Table 1701.2 Standards

  ASTM D2657 Heat Fusion Joining of Polyolefin Pipe and Fittings

  IAPMO PS 25 Metallic Fittings for Joining Polyethylene Pipe for Water Service and Yard Piping

  Note: For SI units: 1 inch = 25 mm

  2025 CALIFORNIA PLUMBING CODE 453

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

  "The information contained in this appendix is not part of this American National Standard (ANS) and has not been processed in accordance with ANSI's requirements for an ANS. As such, this appendix may contain material that has not been subjected to public review or a consensus process. In addition, it does not contain requirements necessary for conformance to the standard."

  The following IAPMO Installation Standard is included here for the convenience of the users of the Uniform Plumbing Code. It is not considered as a part of the Uniform Plumbing Code unless formally adopted as such. This Installation Standard is an independent, stand-alone document published by the International Association of Plumbing and Mechanical Officials and is printed herein by the expressed written permission of IAPMO.

  INSTALLATION STANDARD FOR PEX TUBING SYSTEMS

  FOR HOT- AND COLD-WATER DISTRIBUTION

  IAPMO IS 31-2022

  The provisions contained in this appendix are not mandatory unless specifically adopted by a state agency, or referenced in the adopting ordinance.

  1 Scope

  1.1 General

  1.1.1 This Standard specifies requirements for the installation of SDR 9 CTS crosslinked polyethylene (PEX) tubing and fittings, including cold-expansion, crimp, press, and mechanical compression fittings, intended for hot- and cold-water distribution systems within buildings.

  1.1.2 This Standards applies to

• CPC § 309.3 Medium relevance — show source text

  309.3 Burred Ends. Burred ends of pipe and tubing shall be reamed to the full bore of the pipe or tube, and chips shall be removed.

  309.4 Installation Practices. Plumbing systems shall be installed in a workmanlike manner which is in accordance with this code, applicable standards, and the manufacturer’s installation instructions. All materials shall be installed so as not to adversely affect the systems and equipment or the structure of the building, and in compliance with all laws and other provisions of this code. All plumbing systems shall be in accordance with construction documents approved by the Authority Having Jurisdiction. 309.5 Sound Transmission. Plumbing piping systems shall be designed and installed in conformance with sound limitations as required in the California Building Code .

  309.6 Dead Legs. Dead legs shall have a method of flushing.

  310.0 Prohibited Fittings and Practices.

  310.1 Fittings. No double hub fitting, single or double tee branch, single or double tapped tee branch, side inlet quarter bend, running thread, band, or saddle shall be used as a drainage fitting.

  310.2 Drainage and Vent Piping. No drainage or vent piping shall be drilled and tapped for the purpose of making connections thereto, and no cast-iron soil pipe shall be threaded.

  310.3 Waste Connection. No waste connection shall be

  made to a closet bend or stub of a water closet or similar fix ture.

  310.4 Use of Vent and Waste Pipes. Except as hereinafter provided in Section 908.0 through Section 911.0, no vent pipe shall be used as a soil or waste pipe, nor shall a soil or waste pipe be used as a vent. Also, single-stack drainage and venting systems with unvented branch lines are prohibited.

  310.5 Obstruction of Flow. No fitting, fixture and piping connection, appliance, device, or method of installation that obstructs or retards the flow of water, wastes, sewage, or air in the drainage or venting systems, in an amount exceeding the normal frictional resistance to flow, shall be used unless it is indicated as acceptable in this code or is approved in accordance with Section 301.2 of this code. The enlargement of a 3 inch (80 mm) closet bend or stub to 4 inches (100 mm) shall not be considered an obstruction.

  310.6 Dissimilar Metals. Except for necessary valves, where intermembering or mixing of dissimilar metals occurs, the point of connection shall be confined to exposed or accessible locations.

  310.7 Direction of Flow. Valves, pipes, and fittings shall be installed in correct relationship to the direction of flow.

  310.8 Screwed Fittings. Screwed fittings shall be ABS, cast-iron, copper, copper alloy, malleable iron, PVC, steel, or other approved materials. Threads shall be tapped out of solid metal or molded in solid ABS or PVC.

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  GENERAL REGULATIONS

  310.9 Female Plastic Connections. Female plastic tapered (NPT) threaded connections shall not be allowed to be used when threaded onto a male metallic connection.

• CPC § 309.0 Medium relevance — show source text

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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)

  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 § 6.4 Medium relevance — show source text

  For pools constructed on or after January 1, 2013, pool equipment shall be enclosed as follows: 1. All equipment installed for recirculation, filtration and disinfection of pool water shall be installed so that access is limited to persons authorized by the pool owner or operator; and 2. Pool equipment shall be mounted on a continuous slab of concrete or other equivalent easily cleanable and nonabsorbent material; and 3. Floors shall be sloped a minimum of [1] / 4 inch (6.4 mm) per foot to a drain.

  2025 CALIFORNIA BUILDING CODE 31B-11

  on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

  PUBLIC POOLS

  SECTION 3123B—GENERAL REQUIREMENTS

  3123B.1 System description. Each pool shall be provided with a separate recirculation system designed for the continuous recircula- tion, filtration and disinfection of the pool water. The system shall consist of pumps, filters, chemical feeders, skimmers or perimeter overflow systems, valves, pipes, connections, fittings and appurtenances.

  Exception: Pools using fresh water equivalent in flow to the requirements of Section 3124B.

  Note: Fresh makeup pool water shall conform to the water quality standards of Section 65531, Chapter 20, Title 22, California Code of Regulations.

  3123B.2 Equipment. All pumps, filters, chemical feeders, skimmers and supplemental equipment shall comply with the applicable requirements established by the NSF/ANSI 50-2012 performance standard effective September 2012.

  3123B.3 Installation. All equipment related to pool operations shall be installed and maintained according to this chapter and in accor- dance with the equipment manufacturer’s written instructions.

  3123B.4 Equipment access. All filters, valves, pumps, strainers and equipment shall be readily accessible for repair and replacement.

  SECTION 3124B—TURNOVER TIME

  The recirculation system shall have the capacity to provide a complete turnover of pool water in: 1. One-half hour or less for a spa pool; and 2. One-half hour or less for a spray ground; and 3. One hour or less for a wading pool; and 4. Two hours or less for a medical pool; and 5. Six hours or less for all other types of public pools.

  SECTION 3125B—RECIRCULATION PIPING SYSTEM AND COMPONENTS

  3125B.1 Line sizes. Pipes shall be sized so flow velocity of piping systems including all pipes and fittings other than inlet devices or venturi throats shall not exceed 6 feet per second (1.829 m/s) in any suction or copper piping and 8 feet per second (2.438 m/s) in any portion of the return system.

  3125B.1.1 Materials. All piping, tubing and fittings shall comply with the applicable standards for potable water system materials set forth in Chapter 6 of the California Plumbing Code.