Cross-Connections and Backflow Protection

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

• CPC § 601.8.1.1 High relevance — show source text

  601.8.1.1 Equipment using potable water shall be so installed as to prevent back-siphonage into the potable water system.

  601.8.1.2 Non-potable water is permitted only in those parts of o ffi cial plants where no edible product is han- dled or prepared, and then only for limited purposes, such as on ammonia condensers not connected with the potable water supply, in vapor lines serving inedi- ble product rendering tanks, in connection with equip- ment used for washing and washing inedible products preparatory to tanking, and in sewer lines for moving heavy solids in sewage. In all cases, non-potable water lines shall be clearly identi fi ed and shall not be cross connected with the potable water supply.

  Exception: Cross connection is permitted if this is necessary for fi re protection, and such connection is of a type with a break to ensure against accidental contamination, and is approved by local authorities or by the Department.

  601.8.2 All pipelines, reservoirs, tanks, cooling towers, and like equipment employed in handling reused water shall be constructed and installed so as to facilitate their cleaning and inspection.

  601.8.3 Hot water for cleaning rooms and equipment shall be delivered under pressure to outlets and shall be of such temperature as to accomplish a thorough cleanup.

  601.8.3.1 An ample supply of water at not less than 180°F (82°C) shall be available when used for san- itizing purposes.

  601.8.4 Pens, alleys, and runways shall have hose con- nections for cleanups purposes.

  602.0 Unlawful Connections.

  602.1 Prohibited Installation. No installation of potable water supply piping, or part thereof, shall be made in such a manner that it will be possible for used, unclean, polluted, or contaminated water, mixtures, or substances to enter a portion of such piping from a tank, receptor, equipment, or plumbing fixture by reason of backsiphonage, suction, or other cause, either during normal use and operation thereof, or where such tank, receptor, equipment, or plumbing fixture is flooded or subject to pressure exceeding the operating pressure in the hot or cold water piping. 602.2 Cross-Contamination. No person shall make a connection or allow one to exist between pipes or conduits carrying domestic water supplied by a public or private building supply system, and pipes, conduits, or fixtures containing or carrying water from any other source or containing or carrying water that has been used for any purpose whatsoever, or piping carrying chemicals, liquids, gases, or substances whatsoever, unless there is provided a backflow prevention device approved for the potential hazard and maintained in accordance with this code. Each point of use shall be separately protected where potential cross-contamination of individual units exists.

  602.3 Backflow Prevention. No plumbing fixture, device, or construction shall be installed or maintained, or shall be connected to a domestic water supply, where such installation or connection provides a possibility of polluting such water supply or cross-connection between a distributing system of water for drinking and domestic purposes and water that becomes contaminated by such plumbing fixture, device, or construction unless there is provided a backflow prevention device approved for the potential hazard.

• CPC § 602.4 High relevance — show source text

  602.4 Approval by Authority. No water piping supplied by a private water supply system shall be connected to any other source of supply without the approval of the Authority Having Jurisdiction, Health Department, or other department having jurisdiction.

  603.0 Cross-Connection Control.

  603.1 General. Cross-connection control shall be provided in accordance with the provisions of this chapter.

  No person shall install a water-operated equipment or mechanism, or use a water-treating chemical or substance, where it is found that such equipment, mechanism, chemical, or substance causes pollution or contamination of the domestic water supply. Such equipment or mechanism shall be permitted where equipped with an approved backflow prevention device or assembly.

  603.2 Approval of Devices or Assemblies. Before a device or an assembly is installed for the prevention of backflow, it shall have first been approved by the Authority Having Jurisdiction. Devices or assemblies shall be tested in accordance with recognized standards or other standards acceptable to the Authority Having Jurisdiction. Backflow prevention devices and assemblies shall comply with Table 603.2, except for specific applications and provisions as stated in Section 603.5.1 through Section 603.5.22.

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  WATER SUPPLY AND DISTRIBUTION

  Devices or assemblies installed in a potable water supply system for protection against backflow shall be maintained in good working condition by the person or persons having control of such devices or assemblies. Such devices or assemblies shall be tested at the time of installation, repair, or relocation and not less than on an annual schedule thereafter, or more often where required by the Authority Having Jurisdiction. Where found to be defective or inoperative, the device or assembly shall be repaired or replaced. No device or assembly shall be removed from use or relocated or other device or assembly substituted, without the approval of the Authority Having Jurisdiction.

  Testing or maintenance shall be performed by a certified backflow assembly tester or repairer certified in accordance with ASSE/IAPMO/ANSI Series 5000 or any other additional certification approved by the Authority Having Jurisdiction.

  603.3 Backflow Prevention Devices, Assemblies, and Methods. Backflow prevention devices, assemblies, and methods shall comply with Section 603.3.1 through Section 603.3.12.

  603.3.1 Air Gap. The minimum air gap to afford backflow protection shall be in accordance with Table 603.3.1. 603.3.2 Atmospheric Vacuum Breaker (AVB). An atmospheric vacuum breaker consists of a body, a checking member, and an atmospheric port.

  603.3.3 Hose Connection Backflow Preventer. A hose connection backflow preventer consists of two independent check valves with an independent atmospheric vent between and a means of field testing and draining.

  603.3.4 Double Check Valve Backflow Prevention Assembly (DC). A double check valve backflow prevention assembly consists of two independently acting internally loaded check valves, four properly located test cocks, and two isolation valves.

  603.3.5 Pressure Vacuum Breaker Backflow Pre- vention Assembly (PVB). A pressure vacuum breaker backflow prevention assembly consists of a loaded air inlet valve, an internally loaded check valve, two properly located test cocks, and two isolation valves.

• CPC § 602.0 High relevance — show source text

  602.0 Unlawful Connections.

  602.1 Prohibited Installation. No installation of potable water supply piping, or part thereof, shall be made in such a manner that it will be possible for used, unclean, polluted, or contaminated water, mixtures, or substances to enter a portion of such piping from a tank, receptor, equipment, or plumbing fixture by reason of backsiphonage, suction, or other cause, either during normal use and operation thereof, or where such tank, receptor, equipment, or plumbing fixture is flooded or subject to pressure exceeding the operating pressure in the hot or cold water piping. 602.2 Cross-Contamination. No person shall make a connection or allow one to exist between pipes or conduits carrying domestic water supplied by a public or private building supply system, and pipes, conduits, or fixtures containing or carrying water from any other source or containing or carrying water that has been used for any purpose whatsoever, or piping carrying chemicals, liquids, gases, or substances whatsoever, unless there is provided a backflow prevention device approved for the potential hazard and maintained in accordance with this code. Each point of use shall be separately protected where potential cross-contamination of individual units exists.

  602.3 Backflow Prevention. No plumbing fixture, device, or construction shall be installed or maintained, or shall be connected to a domestic water supply, where such installation or connection provides a possibility of polluting such water supply or cross-connection between a distributing system of water for drinking and domestic purposes and water that becomes contaminated by such plumbing fixture, device, or construction unless there is provided a backflow prevention device approved for the potential hazard.

  602.4 Approval by Authority. No water piping supplied by a private water supply system shall be connected to any other source of supply without the approval of the Authority Having Jurisdiction, Health Department, or other department having jurisdiction.

  603.0 Cross-Connection Control.

  603.1 General. Cross-connection control shall be provided in accordance with the provisions of this chapter.

  No person shall install a water-operated equipment or mechanism, or use a water-treating chemical or substance, where it is found that such equipment, mechanism, chemical, or substance causes pollution or contamination of the domestic water supply. Such equipment or mechanism shall be permitted where equipped with an approved backflow prevention device or assembly.

  603.2 Approval of Devices or Assemblies. Before a device or an assembly is installed for the prevention of backflow, it shall have first been approved by the Authority Having Jurisdiction. Devices or assemblies shall be tested in accordance with recognized standards or other standards acceptable to the Authority Having Jurisdiction. Backflow prevention devices and assemblies shall comply with Table 603.2, except for specific applications and provisions as stated in Section 603.5.1 through Section 603.5.22.

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  WATER SUPPLY AND DISTRIBUTION

• CPC § 25.4 High relevance — show source text

  2 Vertical walls, ribs, or similar obstructions extending from the water surface to or above the horizontal plane of the spout opening other than specified in Footnote 1 above. The effect of three or more such vertical walls or ribs has not been determined. In such cases, the air gap shall be measured from the top of the wall. 3 The effective opening shall be the minimum cross-sectional area at the seat of the control valve or the supply pipe or tubing that feeds the device or outlet. Where two or more lines supply one outlet, the effective opening shall be the sum of the cross-sectional areas of the individual supply lines or the area of the single outlet, whichever is smaller. 4 Air gaps less than 1 inch (25.4 mm) shall be approved as a permanent part of a listed assembly that has been tested under actual backflow conditions with vacuums of 0 to 25 inches of mercury (85 kPa).

  603.5.7 Outlets with Hose Attachments. Potable water outlets with hose attachments, other than water heater drains, boiler drains, and clothes washer connections, shall be protected by a nonremovable hose bibbtype backflow preventer, a nonremovable hose bibb-type vacuum breaker, or by an atmospheric vacuum breaker installed not less than 6 inches (152 mm) above the highest point of usage located on the discharge side of the last valve. In climates where freezing temperatures occur, a listed self-draining frost-proof hose bibb with an integral backflow preventer or vacuum breaker shall be used. 603.5.8 Water-Cooled Equipment. Water-cooled compressors, degreasers, or other water-cooled equipment shall be protected by a backflow preventer installed in accordance with the requirements of this chapter. Water-cooled equipment that produces backpressure shall be equipped with the appropriate protection. 603.5.9 Aspirators. Water inlets to water-supplied aspirators shall be equipped with a vacuum breaker installed in accordance with its listing requirements and this chapter. The discharge shall drain through an air gap. Where the tailpiece of a fixture to receive the discharge of an aspirator is used, the air gap shall be located above the flood-level rim of the fixture.

  603.5.10 Steam or Hot Water Boilers. Potable water connections to steam or hot water boilers shall be protected from backflow by a double check valve backflow prevention assembly, backflow preventer with intermediate atmospheric vent and pressure reducing valve, or reduced pressure principle backflow prevention assembly in accordance with Table 603.2. Where chemicals are introduced into the system a reduced pressure principle backflow prevention assembly shall be provided in accordance with Table 603.2.

  603.5.11 Nonpotable Water Piping. In cases where it is impractical to correct individual cross-connections on the domestic waterline, the line supplying such outlets

  shall be considered a nonpotable water line. No drinking or domestic water outlets shall be connected to the nonpotable waterline. Where possible, portions of the nonpotable waterline shall be exposed, and exposed portions shall be properly identified in a manner satisfactory to the Authority Having Jurisdiction. Each outlet on the nonpotable waterline that is permitted to be used for drinking or domestic purposes shall be posted: “CAUTION: NONPOTABLE WATER, DO NOT DRINK.”

  [HCD 1 & HCD 2] An international symbol of a glass in a circle with a slash through it shall be provided sim- ilar to that shown in Figure 601.

• CPC § 603.5.9 High relevance — show source text

  603.5.9 Aspirators. Water inlets to water-supplied aspirators shall be equipped with a vacuum breaker installed in accordance with its listing requirements and this chapter. The discharge shall drain through an air gap. Where the tailpiece of a fixture to receive the discharge of an aspirator is used, the air gap shall be located above the flood-level rim of the fixture.

  603.5.10 Steam or Hot Water Boilers. Potable water connections to steam or hot water boilers shall be protected from backflow by a double check valve backflow prevention assembly, backflow preventer with intermediate atmospheric vent and pressure reducing valve, or reduced pressure principle backflow prevention assembly in accordance with Table 603.2. Where chemicals are introduced into the system a reduced pressure principle backflow prevention assembly shall be provided in accordance with Table 603.2.

  603.5.11 Nonpotable Water Piping. In cases where it is impractical to correct individual cross-connections on the domestic waterline, the line supplying such outlets

  shall be considered a nonpotable water line. No drinking or domestic water outlets shall be connected to the nonpotable waterline. Where possible, portions of the nonpotable waterline shall be exposed, and exposed portions shall be properly identified in a manner satisfactory to the Authority Having Jurisdiction. Each outlet on the nonpotable waterline that is permitted to be used for drinking or domestic purposes shall be posted: “CAUTION: NONPOTABLE WATER, DO NOT DRINK.”

  [HCD 1 & HCD 2] An international symbol of a glass in a circle with a slash through it shall be provided sim- ilar to that shown in Figure 601.

  603.5.12 Beverage Dispensers. Potable water supply to carbonated beverage dispensers shall be protected by an air gap or a vented backflow preventer that complies with ASSE 1022. For carbonated beverage dispensers, piping material installed downstream of the backflow preventer shall not be affected by carbon dioxide gas. Non-carbonated beverage dispensers, such as ice makers and coffee machines, shall be protected by an air gap or dual check backflow preventer that comply with ASSE 1032 or ASSE 1024.

  603.5.13 Deck-Mounted and Equipment- Mounted Vacuum Breakers. Deck-mounted or equipment-mounted vacuum breakers shall be installed in accordance with their listing and the manufacturer’s installation instructions, with the critical level not less than 1 inch (25.4 mm) above the flood-level rim.

  603.5.14 Protection from Fire Systems.

  Note: Fire Protection Systems has not been adopted by the State Fire Marshal. This section cannot be adopted or enforced pursuant to California Health and Safety Code 13114.7(a), which is being cited for reference. California Health and Safety Code 13114.7.

  (a) For the purposes of this section the following are definitions of class I and class II systems:

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  WATER SUPPLY AND DISTRIBUTION

• CPC § 2025 High relevance — show source text

  An acceptable air supply for combustion and ventilation is necessary for the proper operation of fuel-burning appliances. A shortage of combustion air can result in incomplete combustion and the production of poisonous gases, such as carbon monoxide or appliance overheating. Ventilation air provides cooling for the appliance casing and internal controls. Inadequate ventilation of the space in which an appliance is installed can result in increased surrounding temperatures that stress the appliance itself or other appliances in the vicinity.

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  FORMAT OF THE UNIFORM PLUMBING CODE

  Chapter 6 Water Supply and Distribution.

  Chapter 6 regulates the design, material, and installation of water supply and distribution systems, including residential fire sprinklers. The water supply and distribution system is designed to achieve the correct water pressure and flow rates and avoid cross-connections. For fixtures to perform properly, an acceptable supply of potable water is essential to their operation and use. Cross-connections and backflow are ranked as the highest priority because of the long history of recognized health risks posed by cross-connections, outbreaks, or cases of waterborne disease. Piping materials and components are evaluated for their possible effect on the potable water with which they are in contact. The intent is to control the potential adverse health effects produced by indirect additives, products, and materials that come in contact with potable water. When selecting materials for water supply and distribution systems, consider water pressure, water temperature, compatibility with the water supply, durability, support, and sustainability.

  In addition, this chapter regulates the design, location, materials, and installation of multipurpose and stand-alone sprinkler systems that do not include the use of antifreeze. Where systems are installed as a portion of the water distribution system under the requirements of this chapter and are not provided with a fire department connection, backflow protection for the water supply system is not required.

  Chapter 7 Sanitary Drainage.

  This chapter regulates the design and installation of sanitary drainage systems to ensure they will work as intended. Drainage piping should not be oversized nor undersized, and constructed of approved materials to guard against fouling, deposit of solids, clogging, and with cleanouts so arranged that the pipes may be readily cleaned. The purpose of the sanitary drainage system is to remove effluent discharged from plumbing fixtures and other equipment to an approved point of disposal, such as a public sanitary system or private sewage disposal system.

  The basics of a sanitary drainage system include public and private sewage disposal; selection of materials; installation of the building drain and sewer; joining methods for pipe and fittings; drainage fixture units for sizing the drainage system; sumps and ejectors; vent sizing and length of vents; and testing.

  Chapter 8 Indirect Wastes.

  Chapter 8 regulates indirect waste connections that are required for plumbing fixtures and plumbing appliances dealing with food preparation, dishwashing, potable liquids, and similar equipment. An indirect connection prevents sewage from backing up into a fixture or appliance, thus providing protection against potential health hazards. The waste pipe discharges through an air gap or air break into a waste receptor or standpipe. The protection in the form of an air gap is necessary when the contamination is a potential health hazard or cross connection with the potable water system. Where there is no possibility of contaminating the potable water (nonpotable discharge), the indirect waste pipe may connect in the form of an air break.

• CPC § 601.3.2 High relevance — show source text

  Table 601.3.2 Minimum Length of Color Field and Size of Letters . . . . . . .138

  601.4 Schools of Cosmetology and Cosmetological Establishments . .138

  601.5 Meat and Poultry Processing Plants . . . . . . . . . . . . . . . . . . . . . .138

  601.6 Collection Centers and

  Facilities . . . . . . . . . . . . . . . . . . . .139

  601.7 Renderers . . . . . . . . . . . . . . . . . . .139

  601.8 Horse Meat and Pet Food

  Establishments . . . . . . . . . . . . . . .139

  602.0 Unlawful Connections . . . . . . . . . .139

  602.1 Prohibited Installation . . . . . . . . . .139

  602.2 Cross-Contamination . . . . . . . . . .139

  602.3 Backflow Prevention . . . . . . . . . . .139

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  TABLE OF CONTENTS

  602.4 Approval by Authority . . . . . . . . . .139

  603.0 Cross-Connection Control . . . . . .139

  603.1 General . . . . . . . . . . . . . . . . . . . . .139

  603.2 Approval of Devices or Assemblies . . . . . . . . . . . . . . . . . .139

  603.3 Backflow Prevention Devices, Assemblies, and Methods . . . . . .140

  603.4 General Requirements . . . . . . . . .140

  603.5 Specific Requirements . . . . . . . . .141

  Table 603.2 Backflow Prevention Devices, Assemblies, and Methods . . . . . .142

  Table 603.3.1 Minimum Air Gaps for Water Distribution . . . . . . . . . . . . . . . . . .144

  604.0 Materials . . . . . . . . . . . . . . . . . . . .146

  604.1 Pipe, Tube, and Fittings . . . . . . . .146

  604.2 Lead Content . . . . . . . . . . . . . . . .147

  604.3 Copper or Copper Alloy Tube . . .147

  604.4 Hard-Drawn Copper or Copper Alloy Tubing . . . . . . . . . . . . . . . . .147

  604.5 Flexible Connectors . . . . . . . . . . .147

  604.6 Cast-Iron Fittings . . . . . . . . . . . . .147

  604.7 Malleable Iron Fittings . . . . . . . . .147

  604.8 Previously Used Piping and Tubing . . . . . . . . . . . . . . . . . . . . . .147

  604.9 Epoxy Coating . . . . . . . . . . . . . . .147

  604.10 Plastic Materials . . . . . . . . . . . . . .147

• CPC § 603.2 High relevance — show source text

  Have outlet open to
  atmosphere. Minimum of 6 inches or listed
  distance above all downstream piping and
  flood level rim of receptor.4,5| |Backflow preventer for
  Carbonated Beverage
  Dispensers (two inde-
  pendent check valves
  with a vent to the atmos-
  phere)|ASSE 1022|X|X|X|X|Installation includes carbonated beverage
  machines or dispensers. These devices
  operate under intermittent or continuous
  pressure conditions.| |Backflow preventer with
  intermediate atmos-
  pheric vent|ASSE 1012|X|X|—|—|Installation of potable water connections to
  water boilers. No high-hazard chemicals
  shall be introduced into the system using
  such devices. Designed to operate under con-
  tinuous pressure conditions. May discharge
  water.| |Backflow preventer with
  intermediate atmospheric
  vent and pressure reduc-
  ing valve|ASSE 1081|X|X|—|—|Installation of potable water connections to
  water boilers. No high-hazard chemicals
  shall be introduced into the system using
  such devices. Designed to operate under con-
  tinuous pressure conditions. May discharge
  water.| |Chemical dispenser with
  integral backflow protec-
  tion|ANSI/CAN/
  ASSE/IAPMO
  1055|X|––|X|––|Shall be installed in accordance with
  manufacturer’s installation instructions with
  dedicated water supply whenever possible.| |Dual check backflow
  preventer|ASSE 1024|X|X|—|—|Installation does not include carbonated drink
  dispensers.| |Dual check backflow
  preventer wall hydrants,
  freeze resistant|ASSE 1053|X|––|X|––|Such devices are not for use under
  continuous pressure conditions.4| |Double Check Detector
  Fire Protection Backflow
  Prevention Assembly
  (two independent check
  valves with a parallel
  detector assembly con-
  sisting of a water meter
  and a double check valve
  backflow prevention
  assembly and means for
  field testing)|ASSE 1048|X|X|––|––|Horizontal unless otherwise listed. Access
  and clearance shall be in accordance with the
  manufacturer’s instructions, and not less than
  a 12 inch clearance at the bottom for mainte-
  nance. May need platform/ladder for test and
  repair. Does not discharge water. Installation
  includes a fire protection system and is
  designed to operate under continuous pres-
  sure conditions.|

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  WATER SUPPLY AND DISTRIBUTION

  |TABLE 603.2 BACKFLOW PREVENTION DEVICES, ASSEMBLIES,

• CPC § 2025 Medium relevance — show source text

  The safety requirements provide protection for piping, material, and structures, with provisions for installation practices, removing stress and strain of the pipe, sleeving, and hanger support. The building’s structural stability is protected by the regulations for cutting and notching of structural members.

  Chapter 4 Plumbing Fixtures and Fixture Fittings.

  This chapter regulates the minimum number of plumbing fixtures of a specific type and quality for each building. The fixtures must be properly installed to be usable by the individuals occupying the building. The quality and design of every fixture must conform to the applicable referenced standard. Compliance with this chapter will result in a building or structure having acceptable plumbing fixtures for the sanitary, hygienic, cleaning, washing, and food preparation needs of the occupants. In addition to ensuring resilient fixtures, the chapter also takes into consideration gender-neutral facilities and contains provisions for privacy compartments.

  Chapter 5 Water Heaters.

  Chapter 5 regulates the design, approval, installation, and safety devices of fuel burning and other types of water heaters with the combustion air requirements for ventilation and dilution of flue gases for appliances installed in buildings. This chapter does not apply to direct-vent appliances. In addition, this chapter regulates the design, construction, installation, and maintenance of chimneys, vents, and their connections to fuel-burning appliances. Methods to supply combustion air may be supplied from an indoor air supply, outdoor air supply, a combination of indoor and outdoor air supply, mechanical air supply, or an engineered system. Combustion air provisions are based on the number of openings and the total opening size required based on the total energy input rating of the appliance. An acceptable air supply for combustion and ventilation is necessary for the proper operation of fuel-burning appliances. A shortage of combustion air can result in incomplete combustion and the production of poisonous gases, such as carbon monoxide or appliance overheating. Ventilation air provides cooling for the appliance casing and internal controls. Inadequate ventilation of the space in which an appliance is installed can result in increased surrounding temperatures that stress the appliance itself or other appliances in the vicinity.

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  Chapter 6 Water Supply and Distribution.

  Chapter 6 regulates the design, material, and installation of water supply and distribution systems, including residential fire sprinklers. The water supply and distribution system is designed to achieve the correct water pressure and flow rates and avoid cross-connections. For fixtures to perform properly, an acceptable supply of potable water is essential to their operation and use. Cross-connections and backflow are ranked as the highest priority because of the long history of recognized health risks posed by cross-connections, outbreaks, or cases of waterborne disease. Piping materials and components are evaluated for their possible effect on the potable water with which they are in contact. The intent is to control the potential adverse health effects produced by indirect additives, products, and materials that come in contact with potable water. When selecting materials for water supply and distribution systems, consider water pressure, water temperature, compatibility with the water supply, durability, support, and sustainability.

• CPC § 91761-2816 Medium relevance — show source text

  Education and Training Seminars: IAPMO specializes in conducting training and education, including fulfilling continuing education requirements, on the UPC and UMC as well as all of the most commonly utilized codes in the Construction Trades. Special seminars on industry or code subjects are expeditiously created and delivered upon request. Please call to obtain the seminar schedule or to arrange for a custom special seminar.

  Backflow Prevention Institute – IAPMO:

  The IAPMO Backflow Prevention Institute provides professional education and training for the control of hazards to our water supply and is dedicated to water-system safety worldwide. The Institute provides training in backflow prevention and cross-connection control. This program includes backflow preventers, testers, repairers, cross-connection control surveyors, program administrators and fire-sprinkler backflow preventer testers. Each of these courses provides compliance certification to American Society of Sanitary Engineering (ASSE) Series 5000 Professional Qualification Standards.

  Backflow Prevention Reference Manual:

  This unique 300-page manual contains full-color illustrations and sections relating to real-world installations, backflow prevention, testing cross-connection control, repair and inspections. The manual is an excellent textbook and a reference the inspectors in every jurisdiction should have access too. It is also an important resource for system designers, urban planners and utility companies – professionals on both sides of the water meter.

  ANSI Z124 Standards:

  These standards are written to specifically address a variety of plastic plumbing fixtures and components. They are available individually, or may be grouped for quantity discounts.

  IAPMO Installation Standards:

  IAPMO standards committees have formulated installation standards for a wide variety of commonly used plumbing materials and systems. The IAPMO installation standards are included after the text of the Uniform Plumbing Code, or can be purchased separately.

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  RELATED PUBLICATIONS AND SERVICES

  The Documents Listed are Not by this Reference Adopted by The State of California.

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  OFFICIAL Magazine: IAPMO’s quarterly publication features informative articles related to Plumbing and Mechanical HVACR installations, award winning general interest features, technical columns and industry updates. Subscriptions are available and all IAPMO members receive a free copy of every issue!

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  HOW TO CONTACT IAPMO

  Mailing Address: 4755 East Philadelphia Street, Ontario, California 91761-2816

  Main Number: 909-472-4100 • Publication Orders: 800-85-IAPMO • Publication Fax: 877-85-CODES

  Website: www.iapmo.org • Office Hours: Monday – Friday, 8am – 5pm Pacific Time

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• CPC § 91761-2816 Medium relevance — show source text

  Trailer Standards:

  IAPMO has developed a number of standards for specialty products used in manufactured homes and recreational vehicles. These standards are available individually, or they may be purchased as a set.

  Education and Training Seminars: IAPMO specializes in conducting training and education, including fulfilling continuing education requirements, on the UPC and UMC as well as all of the most commonly utilized codes in the Construction Trades. Special seminars on industry or code subjects are expeditiously created and delivered upon request. Please call to obtain the seminar schedule or to arrange for a custom special seminar.

  Backflow Prevention Institute – IAPMO:

  The IAPMO Backflow Prevention Institute provides professional education and training for the control of hazards to our water supply and is dedicated to water-system safety worldwide. The Institute provides training in backflow prevention and cross-connection control. This program includes backflow preventers, testers, repairers, cross-connection control surveyors, program administrators and fire-sprinkler backflow preventer testers. Each of these courses provides compliance certification to American Society of Sanitary Engineering (ASSE) Series 5000 Professional Qualification Standards.

  Backflow Prevention Reference Manual:

  This unique 300-page manual contains full-color illustrations and sections relating to real-world installations, backflow prevention, testing cross-connection control, repair and inspections. The manual is an excellent textbook and a reference the inspectors in every jurisdiction should have access too. It is also an important resource for system designers, urban planners and utility companies – professionals on both sides of the water meter.

  ANSI Z 124 Standards:

  These standards are written to specifically address a variety of plastic plumbing fixtures and components. They are available individually, or may be grouped for quantity discounts.

  IAPMO Installation Standards:

  IAPMO standards committees have formulated installation standards for a wide variety of commonly used plumbing materials and systems. The IAPMO installation standards are included after the text of the Uniform Plumbing Code, or can be purchased separately.

  xxiv 2025 CALIFORNIA PLUMBING CODE

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

  RELATED PUBLICATIONS AND SERVICES

  The Documents Listed are Not by this Reference Adopted by The State of California.

  Material and Property Standards: IAPMO does not generally develop material and property standards, but when a need exists the Association will take a leadership role by filling the void. They are available, are subject to amendments and are withdrawn when recognized consensus standards are formulated.

  OFFICIAL Magazine: IAPMO’s quarterly publication features informative articles related to Plumbing and Mechanical HVACR installations, award winning general interest features, technical columns and industry updates. Subscriptions are available and all IAPMO members receive a free copy of every issue!

  Membership in IAPMO: IAPMO membership is open to all interested persons. Membership categories include Student, Individual, Senior, Organizational and Governmental. Member benefits include discounted prices on IAPMO publications, a subscription to Official magazine, and numerous educational and training opportunities.

  HOW TO CONTACT IAPMO

  Mailing Address: 4755 East Philadelphia Street, Ontario, California 91761-2816

  Main Number: 909-472-4100 • Publication Orders: 800-85-IAPMO • Publication Fax: 877-85-CODES

  Website: www.iapmo.org • Office Hours: Monday – Friday, 8am – 5pm Pacific Time

  2025 CALIFORNIA PLUMBING CODE xxv

• CMC § 2025 Medium relevance — show source text

  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.

  2025 CALIFORNIA MECHANICAL CODE xxiii

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

  RELATED PUBLICATIONS AND SERVICES

  The Documents Listed are Not by this Reference Adopted by The State of California.

  Uniform Swimming Pool, Spa, and Hot Tub Code – 2024 Edition: The Uniform Swimming Pool, Spa and Hot Tub Code contains complete and current requirements for the erection, installation, alteration, repair, relocation, replacement, addition to and use or maintenance of these systems.

  Uniform Solar, Hydronics and Geothermal Code – 2024 Edition: The Uniform Solar, Hydronics and Geothermal Code contains complete requirements for the erection, installation, alteration, addition, repair, relocation, replacement, addition to, use or maintenance of these systems.

  Drain Waste and Vent Calculator:

  A slide-rule style calculator provides quick and simple access to the fixture unit and sizing tables of Chapter 7 of the UPC.

  Water Sizing Calculator: Sizing water systems becomes a much simpler task with the use of this handy slide-rule style calculator.

  Natural Gas Pipe Sizing Calculator: This Natural Gas Pipe Sizing Calculator is presented in an easy to use and read slide-rule format. Designed for systems with a supply pressure of six to eight inches of water column, all pipe capacities are given in cubic feet per hour.

  Trailer Standards:

  IAPMO has developed a number of standards for specialty products used in manufactured homes and recreational vehicles. These standards are available individually, or they may be purchased as a set.

  Education and Training Seminars: IAPMO specializes in conducting training and education, including fulfilling continuing education requirements, on the UPC and UMC as well as all of the most commonly utilized codes in the Construction Trades. Special seminars on industry or code subjects are expeditiously created and delivered upon request. Please call to obtain the seminar schedule or to arrange for a custom special seminar.

  Backflow Prevention Institute – IAPMO:

  The IAPMO Backflow Prevention Institute provides professional education and training for the control of hazards to our water supply and is dedicated to water-system safety worldwide. The Institute provides training in backflow prevention and cross-connection control. This program includes backflow preventers, testers, repairers, cross-connection control surveyors, program administrators and fire-sprinkler backflow preventer testers. Each of these courses provides compliance certification to American Society of Sanitary Engineering (ASSE) Series 5000 Professional Qualification Standards.

  Backflow Prevention Reference Manual:

  This unique 300-page manual contains full-color illustrations and sections relating to real-world installations, backflow prevention, testing cross-connection control, repair and inspections. The manual is an excellent textbook and a reference the inspectors in every jurisdiction should have access too. It is also an important resource for system designers, urban planners and utility companies – professionals on both sides of the water meter.

  ANSI Z124 Standards:

  These standards are written to specifically address a variety of plastic plumbing fixtures and components. They are available individually, or may be grouped for quantity discounts.

  IAPMO Installation Standards:

  IAPMO standards committees have formulated installation standards for a wide variety of commonly used plumbing materials and systems. The IAPMO installation standards are included after the text of the Uniform Plumbing Code, or can be purchased separately.