Venting, combination waste-and-vent, and special venting methods

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

• CPC § 910.0 High relevance — show source text

  910.0 Combination Waste and Vent Systems. 910.1 Where Permitted. Combination waste and vent systems shall be permitted where structural conditions preclude the installation of conventional systems as otherwise prescribed by this code. 910.2 Approval. Construction documents for each combination waste and vent system shall first be approved by the Authority Having Jurisdiction before a portion of such system is installed.

  910.3 Vents. Each combination waste and vent system, as defined in Chapter 2, shall be provided with a vent or vents adequate to ensure free circulation of air. A branch exceeding 15 feet (4572 mm) in length shall be separately vented in an approved manner. The area of a vent installed in a combination waste and vent system shall be not less than one-half the inside cross-sectional area of the drainpipe served. The vent connection shall be downstream of the uppermost fixture. 910.4 Connections and Size. Branches serving traps shall connect to the main line at an angle not exceeding 2 percent. Each waste pipe and each trap in such a system shall be not less than two pipe sizes exceeding the sizes required by Chapter 7 of this code, and not less than two pipe sizes exceeding a fixture tailpiece or connection. 910.5 Vertical Waste Pipe. No vertical waste pipe shall be used in such a system, except the tailpiece or connection between the outlet of a plumbing fixture and the trap. Such tailpieces or connections shall be as short as possible, and in no case shall exceed 2 feet (610 mm).

  Exception: Branch lines shall be permitted to have 45 degree (0.79 rad) vertical offsets.

  910.6 Cleanouts. An accessible cleanout shall be installed in each vent for the combination waste and vent system. Cleanouts shall not be required on a wet-vented branch serving a single trap where the fixture tailpiece or connection is not less than 2 inches (50 mm) in diameter and provides ready access for cleaning through the trap.

  910.7 Fixtures. No water closet or urinal shall be installed on such a system. Other one, two, or three unit fixtures remotely located from the sanitary system and adjacent to a combination waste and vent system shall be permitted to be connected to such system in the conventional manner by means of waste and vent pipes of regular sizes, providing that the two pipe size increase required in Section 910.4 is based on the total fixture unit load connected to the system.

  See Appendix B of this code for explanatory notes on the design of combination waste and vent systems.

  911.0 Circuit Venting. 911.1 Circuit Vent Permitted. A maximum of eight flooroutlet water closets, showers, bathtubs, or floor drains con

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  VENTS

  nected to a horizontal branch shall be permitted to be circuit vented. Each trap arm shall connect horizontally to the horizontal branch being circuit vented in accordance with Table 1002.2. The horizontal branch shall be classified as a drain and a vent from the most downstream trap arm connection to the most upstream trap arm connection to the horizontal branch.

  Exception: Back-outlet and wall-hung water closets shall be permitted to be circuit vented provided that no floor-outlet fixtures are connected to the same horizontal branch. Backoutlet and wall-hung water closets shall connect horizontally to the horizontal circuit vented drain.

• CPC § 1.11.0. High relevance — show source text

  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.

  2025 CALIFORNIA PLUMBING CODE 381

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  APPENDIX B

  EXPLANATORY NOTES ON COMBINATION WASTE AND VENT SYSTEMS

  (See Section 910.0 for specific limitations)

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

  B 101.0 General.

  B 101.1 Applicability. This appendix provides general guidelines for the design and installation of a combination waste and vent system.

  B 101.2 General Requirements. Combination waste and vent systems, (which at best are merely an expedient designed to be used in locations where it would be structurally impractical to provide continuous venting of fixtures) as outlined in Section 910.0 of this code, cover the horizontal wet venting of a series of traps using a common waste and vent pipe. Pipe sizes not less than two pipe sizes larger than those required for a conventional system are designed to maintain a wetted perimeter or flow line low enough in the waste pipe to allow adequate air movement in the upper portion, thus balancing the system. One and two unit fixtures that rough in above the floor, shall be permitted to connect to a combination waste and vent system when located as required in Section 910.7.

  Combination waste and vent systems are intended primarily for extensive floor or shower drain installations where separate venting is not practical, for floor sinks in markets, demonstration or work tables in school buildings, or for similar applications where the fixtures are not adjacent to walls or partitions. Due to its oversize characteristics, such a waste system is not self-scouring and, consequently, care shall be exercised as to the type of fixtures connected to it and the location of cleanouts. Given its grease-producing potential, restaurant kitchen equipment shall not be connected to a combination waste and vent system.

  B 101.3 Caution. Caution shall be exercised to exclude appurtenances delivering large quantities or surges of water (such as pumps, sand interceptors, etc.) from combination waste and vent systems so that adequate venting will be maintained. Small fixtures with a waste-producing potential of less than 7 [1] ⁄ 2 gallons per minute (gpm) (0.47 L/s) shall be permitted to be safely assigned a loading value of one unit. Long runs shall be laid at the minimum permissible slope to keep tailpieces as short as possible. Tailpieces shall not exceed 2 feet (610 mm) in length, which shall necessitate slopes up to 45 degrees (0.79 rad) (see definition of horizontal pipe) on some branches.

• CPC § 908.2.4 High relevance — show source text

  908.2.4 Water Closet. The water closet fixture drain or trap arm connection to the wet vent shall be downstream of fixture drain or trap arm connections to the horizontal wet vent.

  908.2.5 Additional Fixtures. Additional fixtures shall discharge downstream of the wet vent system and be conventionally vented. Only the fixtures within the bathroom group shall connect to the wet-vented horizontal branch.

  909.0 Special Venting for Island Fixtures. 909.1 General. Traps for island sinks and similar equipment shall be roughed in above the floor and shall be permitted to be vented by extending the vent as high as possible, but not less than the drainboard height and then returning it downward and connecting it to the horizontal sink drain immediately downstream from the vertical fixture drain. The return vent shall be connected to the horizontal drain through a wyebranch fitting and shall, in addition, be provided with a foot vent taken off the vertical fixture vent by means of a wye branch immediately below the floor and extending to the nearest partition and then through the roof to the open air, or shall be permitted to be connected to other vents at a point not less than 6 inches (152 mm) above the flood-level rim of the fixtures served. Drainage fittings shall be used on the vent below the floor level, and a slope of not less than [1] ⁄ 4 inch per foot (20.8 mm/m) back to the drain shall be maintained. The return bend used under the drainboard shall be a one-piece

  fitting or an assembly of a 45 degree (0.79 rad), a 90 degree (1.57 rad), and a 45 degree (0.79 rad) elbow in the order named. Pipe sizing shall be as elsewhere required in this code. The island sink drain, upstream of the returned vent, shall serve no other fixtures. An accessible cleanout shall be installed in the vertical portion of the foot vent.

  910.0 Combination Waste and Vent Systems. 910.1 Where Permitted. Combination waste and vent systems shall be permitted where structural conditions preclude the installation of conventional systems as otherwise prescribed by this code. 910.2 Approval. Construction documents for each combination waste and vent system shall first be approved by the Authority Having Jurisdiction before a portion of such system is installed.

  910.3 Vents. Each combination waste and vent system, as defined in Chapter 2, shall be provided with a vent or vents adequate to ensure free circulation of air. A branch exceeding 15 feet (4572 mm) in length shall be separately vented in an approved manner. The area of a vent installed in a combination waste and vent system shall be not less than one-half the inside cross-sectional area of the drainpipe served. The vent connection shall be downstream of the uppermost fixture. 910.4 Connections and Size. Branches serving traps shall connect to the main line at an angle not exceeding 2 percent. Each waste pipe and each trap in such a system shall be not less than two pipe sizes exceeding the sizes required by Chapter 7 of this code, and not less than two pipe sizes exceeding a fixture tailpiece or connection. 910.5 Vertical Waste Pipe. No vertical waste pipe shall be used in such a system, except the tailpiece or connection between the outlet of a plumbing fixture and the trap. Such tailpieces or connections shall be as short as possible, and in no case shall exceed 2 feet (610 mm).

• CPC § 908.1 High relevance — show source text

  908.1 Vertical Wet Venting . . . . . . . . . . .190

  908.2 Horizontal Wet Venting for a Bathroom Group . . . . . . . . . . . . . .191

  909.0 Special Venting for Island Fixtures . . . . . . . . . . . . . . . . . . . . .191

  909.1 General . . . . . . . . . . . . . . . . . . . . .191

  910.0 Combination Waste and Vent

  Systems . . . . . . . . . . . . . . . . . . . .191

  910.1 Where Permitted . . . . . . . . . . . . . .191

  910.2 Approval . . . . . . . . . . . . . . . . . . . .191

  910.3 Vents . . . . . . . . . . . . . . . . . . . . . .191

  910.4 Connections and Size . . . . . . . . .191

  910.5 Vertical Waste Pipe . . . . . . . . . . .191

  910.6 Cleanouts . . . . . . . . . . . . . . . . . . .191

  910.7 Fixtures . . . . . . . . . . . . . . . . . . . . .191

  911.0 Circuit Venting . . . . . . . . . . . . . . .191

  911.1 Circuit Vent Permitted . . . . . . . . .191

  911.2 Circuit Vent Size and

  Connection . . . . . . . . . . . . . . . . . .192

  911.3 Relief Vent . . . . . . . . . . . . . . . . . .192

  911.4 Slope and Size of Horizontal Branch . . . . . . . . . . . . . . . . . . . . .192

  911.5 Additional Fixtures . . . . . . . . . . . .192

  912.0 Engineered Vent System . . . . . . .192

  912.1 General . . . . . . . . . . . . . . . . . . . . .192

  912.2 Minimum Requirements . . . . . . . .192

  CHAPTER 10 TRAPS AND

  INTERCEPTORS . . . . . . . . . . . . .193

  1001.0 General . . . . . . . . . . . . . . . . . . . . .195

  1001.1 Applicability . . . . . . . . . . . . . . . . . .195

  1001.2 Where Required . . . . . . . . . . . . . .195

  1002.0 Traps Protected by Vent Pipes . .195

  1002.1 Vent Pipes . . . . . . . . . . . . . . . . . .195

  1002.2 Fixture Traps . . . . . . . . . . . . . . . .195

  1002.3 Change of Direction . . . . . . . . . . .195

  1002.4 Vent Pipe Opening . . . . . . . . . . . .195

  1003.0 Traps – Described . . . . . . . . . . . .195

  1003.1 General Requirements . . . . . . . . .195

• CPC § 910.7 High relevance — show source text

  910.7 Fixtures. No water closet or urinal shall be installed on such a system. Other one, two, or three unit fixtures remotely located from the sanitary system and adjacent to a combination waste and vent system shall be permitted to be connected to such system in the conventional manner by means of waste and vent pipes of regular sizes, providing that the two pipe size increase required in Section 910.4 is based on the total fixture unit load connected to the system.

  See Appendix B of this code for explanatory notes on the design of combination waste and vent systems.

  911.0 Circuit Venting. 911.1 Circuit Vent Permitted. A maximum of eight flooroutlet water closets, showers, bathtubs, or floor drains con

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  VENTS

  nected to a horizontal branch shall be permitted to be circuit vented. Each trap arm shall connect horizontally to the horizontal branch being circuit vented in accordance with Table 1002.2. The horizontal branch shall be classified as a drain and a vent from the most downstream trap arm connection to the most upstream trap arm connection to the horizontal branch.

  Exception: Back-outlet and wall-hung water closets shall be permitted to be circuit vented provided that no floor-outlet fixtures are connected to the same horizontal branch. Backoutlet and wall-hung water closets shall connect horizontally to the horizontal circuit vented drain.

  911.2 Circuit Vent Size and Connection. The circuit vent size shall be in accordance with Table 703.2 according to the number of circuit vented fixtures connected to the horizontal branch but shall be not less than 2 inches (50 mm) in diameter. The vent shall connect to the horizontal branch on the vertical between the two most upstream trap arms. The circuit vent pipe shall not receive the discharge of soil or

  waste.

  911.2.1 Multiple Circuit Vents. When multiple circuit vents are interconnected according to Section 911.4.1, each individual circuit vent shall be sized according to Section 911.2. The vent pipe connecting each circuit vent shall be sized according to Table 703.2.

  911.3 Relief Vent. A 2 inch (50 mm) relief vent shall be provided for circuit-vented horizontal branches receiving the discharge of four or more water closets when connecting to a drainage stack that receives the discharge of soil or waste from upper horizontal branches.

  911.3.1 Connection and Installation. The relief vent

  shall connect to the horizontal branch between the stack and the most downstream trap arm of the circuit vent. The relief vent shall be installed on the vertical to the

  horizontal branch.

  911.3.2 Fixture Drain. The relief vent is permitted to serve as a fixture drain. Fixtures discharging to a relief vent shall be one or two fixture unit fixtures but shall not

  exceed a total of 4 fixture units.

  911.4 Slope and Size of Horizontal Branch. The vented section of the horizontal branch shall be uniformly sloped and not more than 1 inch per foot (83.3 mm/m). The entire length of the vented section of the horizontal branch shall be sized for the total drainage discharge to the branch according to Table 703.2.

• CPC § 2025 High relevance — show source text

  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. This method is often preferred to prevent splashing. In addition, health care facilities and special wastes must be protected from contamination that may result from the connection to the drainage system. The waste must be treated to prevent any damage to the piping or sewage treatment process. Waste receptors are sized and designed to prevent splashing and allow for peak discharge conditions.

  Chapter 9 Vents.

  Chapter 9 regulates the material, design, and installation of vents. A vent system is a pipe or pipes installed in a drainage system that provide a flow of air to and from the system to ventilate it, provide a circulation of air to eliminate trap siphonage, and reduce back-pressure and vacuum surge. In addition, vents provide the rapid and silent flow of waste without exposing occupants of the building to any sewer gases. Proper installation of vents is crucial, as a telltale sign that there is a problem in the drain and vent system is related to the elevation of the horizontal portion of the venting. Venting is not limited to sanitary drainage systems. Venting methods are applicable to other drainage systems such as those for chemical waste, graywater waste, and clear water waste. Sizing the venting system is directly tied to the design of the drainage system. For example, the velocities in the drainage system and its peak flow rates affect the diameters in the venting system. Where the vertical distance between a fixture outlet and trap is excessive, velocities in the entire drainage system will be greater than those in the vent sizing table. All venting methods in this chapter are categorized as either dry vents or wet vents. Vent stacks, stack vents, branch vents, island vents, relief vents, and individual vents are dry vents. Wet vents (horizontal or vertical), circuit vents, combination drain and vents are versions of “wet venting” in which the vent is wetted by drainage flow.

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• CPC § 2025 High relevance — show source text

  The waste must be treated to prevent any damage to the piping or sewage treatment process. Waste receptors are sized and designed to prevent splashing and allow for peak discharge conditions.

  Chapter 9 Vents.

  Chapter 9 regulates the material, design, and installation of vents. A vent system is a pipe or pipes installed in a drainage system that provide a flow of air to and from the system to ventilate it, provide a circulation of air to eliminate trap siphonage, and reduce back-pressure and vacuum surge. In addition, vents provide the rapid and silent flow of waste without exposing occupants of the building to any sewer gases. Proper installation of vents is crucial, as a telltale sign that there is a problem in the drain and vent system is related to the elevation of the horizontal portion of the venting. Venting is not limited to sanitary drainage systems. Venting methods are applicable to other drainage systems such as those for chemical waste, graywater waste, and clear water waste. Sizing the venting system is directly tied to the design of the drainage system. For example, the velocities in the drainage system and its peak flow rates affect the diameters in the venting system. Where the vertical distance between a fixture outlet and trap is excessive, velocities in the entire drainage system will be greater than those in the vent sizing table. All venting methods in this chapter are categorized as either dry vents or wet vents. Vent stacks, stack vents, branch vents, island vents, relief vents, and individual vents are dry vents. Wet vents (horizontal or vertical), circuit vents, combination drain and vents are versions of “wet venting” in which the vent is wetted by drainage flow.

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  Chapter 10 Traps and Interceptors.

  Chapter 10 regulates the material, design, and installation of traps, interceptors, and separators. Traps are required on drainage type plumbing fixtures and must be self-scouring without interior partitions. Interceptors, on the other hand, are designed to control what goes down a drain. Interceptors are used to keep harmful substances from entering the sanitary drainage system, such as grease, sand, oil and other materials. The retained materials need periodic removal to maintain efficiency and function of the separating device. The capacity of an interceptor is based on retention and flow rate. There are many types of interceptors that are used at beauty salons, hospitals, meat, fish or foul packaging, refineries, repair garages, gas stations, car washing facilities, various plants, factories, and processing sites. The designer of the building is responsible for locating interceptors with the expectation for the frequency of maintenance, ease of cleaning and floor space for equipment.

  Chapter 11 Storm Drainage.

  Chapter 11 regulates the removal of stormwater from roofs, yards, paved areas, and similar areas. The objective of storm drainage systems is to provide a conduit or channel through which runoff will be carried from a point of collection to a point of disposal; this protects the property and the public from the uncontrolled flow of runoff and ensures that drains and inlets are adequately sized to receive the volume of runoff that flows to the drains. For the purpose of system design, it’s necessary to specify the duration of a selected storm.

• CPC § 905.1 High relevance — show source text

  905.1 Grade . . . . . . . . . . . . . . . . . . . . . .190

  905.2 Horizontal Drainage Pipe . . . . . . .190

  905.3 Vent Pipe Rise . . . . . . . . . . . . . . .190

  905.4 Roof Termination . . . . . . . . . . . . .190

  905.5 Location of Opening . . . . . . . . . . .190

  905.6 Common Vertical Pipe . . . . . . . . .190

  906.0 Vent Termination . . . . . . . . . . . . .190

  906.1 Roof Termination . . . . . . . . . . . . .190

  906.2 Clearance . . . . . . . . . . . . . . . . . . .190

  906.3 Use of Roof . . . . . . . . . . . . . . . . .190

  906.4 Outdoor Installations . . . . . . . . . . .190

  906.5 Joints . . . . . . . . . . . . . . . . . . . . . .190

  906.6 Lead . . . . . . . . . . . . . . . . . . . . . . .190

  906.7 Frost or Snow Closure . . . . . . . . .190

  907.0 Vent Stacks and Relief Vents . . . .190

  907.1 Drainage Stack . . . . . . . . . . . . . . .190

  907.2 Yoke Vent . . . . . . . . . . . . . . . . . . .190

  908.0 Wet Venting . . . . . . . . . . . . . . . . .190

  908.1 Vertical Wet Venting . . . . . . . . . . .190

  908.2 Horizontal Wet Venting for a Bathroom Group . . . . . . . . . . . . . .191

  909.0 Special Venting for Island Fixtures . . . . . . . . . . . . . . . . . . . . .191

  909.1 General . . . . . . . . . . . . . . . . . . . . .191

  910.0 Combination Waste and Vent

  Systems . . . . . . . . . . . . . . . . . . . .191

  910.1 Where Permitted . . . . . . . . . . . . . .191

  910.2 Approval . . . . . . . . . . . . . . . . . . . .191

  910.3 Vents . . . . . . . . . . . . . . . . . . . . . .191

  910.4 Connections and Size . . . . . . . . .191

  910.5 Vertical Waste Pipe . . . . . . . . . . .191

  910.6 Cleanouts . . . . . . . . . . . . . . . . . . .191

  910.7 Fixtures . . . . . . . . . . . . . . . . . . . . .191

  911.0 Circuit Venting . . . . . . . . . . . . . . .191

  911.1 Circuit Vent Permitted . . . . . . . . .191

  911.2 Circuit Vent Size and

  Connection . . . . . . . . . . . . . . . . . .192

• CPC § 2025 Medium relevance — show source text

  Appendix A Recommended Rules for Sizing the Water Supply System.

  Appendix A provides a method of sizing the water supply and distribution system that provides precise calculations to establish the proper pressures and flow to the system’s fixtures. The goal of sizing the system is to deliver an acceptable volume of water to the most hydraulically remote fixture during minimum pressure and maximum flow conditions; provide satisfactory water pressure to the most hydraulically remote fixture during minimum pressure and maximum flow conditions; and to prevent excessive water velocity during maximum flow conditions.

  Appendix B Explanatory Notes on Combination Waste and Vent Systems.

  Appendix B contains general guidelines for the design and installation of combination waste and vent systems. These systems are designed for waste piping and are purposely oversized to serve as both a waste and vent pipe to avoid excessive pneumatic effects at fixture drains.

  Appendix C Alternate Plumbing Systems.

  The intent of this appendix is to provide clarification of procedures for the design and approval of engineered plumbing systems, alternate materials, and equipment that are not specifically covered in other parts of the code. Alternative methods are allowed to be used where approved by the authority having jurisdiction. Approval of alternatives is based on a demonstration showing that the method or material used is at least equivalent in strength, deflection, and capacity to that provided by the prescriptive methods and materials.

  Appendix D Sizing Storm Water Drainage Systems.

  Appendix D provides general guidelines for the sizing of stormwater drainage systems. There are two pieces of information that must always be a given. They are the roof size and the rate of rainfall for the area.

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  FORMAT OF THE UNIFORM PLUMBING CODE

  Appendix E Manufactured/Mobile Home Parks and Recreational Vehicle Parks.

  The provisions of this appendix apply to the plumbing and drainage systems of mobile home and recreational vehicle parks. These provisions also apply to the use, maintenance, and installation for supplying fuel gas, water, electricity, and disposal of sewage from accessory buildings or structures, and building components.

  Appendix F Firefighter Breathing Air Replenishment Systems.

  Appendix F provides guidance on installing firefighter breathing air replenishment systems. System components include outside fire department connection panel, interior air fill panel or station, interconnected piping distribution system and pressure monitoring switch. Fire departments access the system through an outside connection panel and are able to pump air into the system. The firefighters inside the structure access the system at fill stations that are found throughout the building. The piping distribution system is made from stainless tubing or other approved materials. It delivers compressed air to the building’s interior air-fill stations and interior air-fill panels. The tubing also acts as a conduit in the interior of the building between the outside connection panel and the air storage system. If the system becomes over-pressurized, the air monitoring system also acts as a pressure relief. A system isolation valve is placed alongside each interior air fill station and interior air fill panel to isolate the system.

  Appendix G Sizing of Venting Systems.

  Appendix G provides added information on the sizing of gas vents. This appendix is useful to the end user for the proper sizing of venting systems. A series of examples are given that show how to use the tables and other requirements of Chapter 5.

  Appendix H Private Sewage Disposal Systems.

• CPC § 3.3.64.1 Medium relevance — show source text

  ** An area within the flood hazard area that is subject to high-velocity wave action, and shown on a Flood Insurance Rate Map or other flood hazard map as Zone V, VO, VE or V1-30. Code. A standard that is an extensive compilation of provisions covering broad subject matter or that is suitable for adoption into law independently of other codes and standards. Combination Temperature and Pressure-Relief Valve. A relief valve that actuates when a set temperature, pressure, or both is reached. Also, known as a T&P Valve. Combination Thermostatic/Pressure Balancing Valve. A mixing valve that senses outlet temperature and incoming hot and cold water pressure and compensates for fluctuations in incoming hot and cold water temperatures, pressures, or both to stabilize outlet temperatures. Combination Waste and Vent System. A specially designed system of waste piping embodying the horizontal wet venting of one or more sinks or floor drains using a common waste and vent pipe adequately sized to provide free movement of air above the flow line of the drain.

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  DEFINITIONS

  Combined Building Sewer. See Building Sewer (Combined).

  Combustible Material. A material that, in the form in which it is used and under the conditions anticipated, will ignite and burn; a material that does not meet the definition of noncombustible. [NFPA 54:3.3.64.1]

  Commercial Modular System. A drinking water treatment unit system consisting of multiple components attached to a manifold, produced specifically for food service applications, and not intended for use in residential applications.

  Commissaries Serving Mobile Food Preparation Units. [DPH] A food establishment in which food, contain- ers, equipment or supplies are stored or handled for use in vehicles, mobile food preparation units, food carts or vending machines.

  Common. That part of a plumbing system that is so designed and installed as to serve more than one appliance, fixture, building, or system.

  Complex System. [BSC-CG & HCD 1] Gray water sys- tems that discharge over 250 gallons (947 L) per day. Condensate. The liquid phase produced by condensation of a gas or vapor.

  Conductor. A pipe inside the building that conveys storm water from the roof to a storm drain, combined building sewer, or other approved point of disposal.

  Confined Space. A space with limited entrance and egress that is not suitable for inhabitants and not intended for continuous human occupancy.

  Construction Documents. Plans, specifications, written, graphic, and pictorial documents prepared or assembled for describing the design, location, and physical characteristics of the elements of a project necessary for obtaining a permit.

  Contamination. An impairment of the quality of the potable water that creates an actual hazard to the public health through poisoning or the spread of disease by sewage, industrial fluids, or waste. Also, defined as High Hazard.

  Continuous Vent. A vertical vent that is a continuation of

  the drain to which it connects.

  Continuous Waste. A drain is connecting the compartments of a set of fixtures to a trap or connecting other permitted fixtures to a common trap.

• CPC § 420.0 Medium relevance — show source text

  SINKS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .420.0

  Approved standards . . . . . . . . . . . . . . . . . . . . . . .420.1 Clinical . . . . . . . . . . . . . . . . . . . . . .205.0, 413.1, 1303.7

  Floor . . . . . . . . . . . . . . . . . . . . . . . . . . . . .421.0, B 101.2

  Island . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .909.1

  Laundry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .420.4 Prohibited types . . . . . . . . . . . . . . . . . . . .405.3, B 101.2

  Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .420.4

  Special use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .406.2 Three-compartment . . . . . . . . . . . . . . . . . . . . . . .1001.2

  SIZE OF

  Building sewers . . . . . . . . . . . .703.2, 717.0, Table 717.1 Cesspools . . . . . . . . . . . . . . . . . . . . . . . . . .Appendix H Chimneys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .509.5.5 Circuit venting . . . . . . . . . . . . . . . . . . . . . . . . . . . . .911.0

  Combination waste

  and vent piping . . . . . . . . . . . . . . . . .910.0, Appendix B Combustion air openings . . . . . . . . . . . . .506.3 – 506.5 Condensate pipe . . . . . . . . . . . . . . . .814.3, Table 814.3 Disposal fields . . . . . . . . . . . . . . . . . . . . . . .Appendix H Drainage piping . . . . . . . . . . . . . . . .Table 702.1, 703.0, Table 703.2, C 304.0,

  E 302.2, E 504.4

  FOG disposal systems . . . . . . . . . . . . . . . . . . . . .1015.3

  Fuel gas piping systems . . . . . .1208.3, 1214.0, 1215.0,

  E 403.2, Table E 403.2

  Fuel gas vents . . . . . . . . . . . . . . . . . . .509.6.2, 509.7.4,

• CPC § 3.3.64.1 Medium relevance — show source text

  Chimney, Low-Heat Appliance-Type. A factorybuilt, masonry, or metal chimney suitable for removing the products of combustion from fuel-burning low-heat appliances producing combustion gases not in excess of 1000°F (538°C) under normal operating conditions, but capable of producing combustion gases of 1400°F (760°C) during intermittent forced firing for periods up to one hour. Temperatures are measured at the appliance flue outlet. Chimney, Medium-Heat Appliance-Type. A factory-built, masonry, or metal chimney suitable for removing the products of combustion from fuel-burning medium-heat appliances producing combustion gases, not in excess of 2000°F (1093°C), measured at the appliance flue outlet.

  Chimney, Residential Appliance-Type. A factorybuilt or masonry chimney suitable for removing products of combustion from residential-type appliances producing combustion gases, not in excess of 1000°F (538°C), measured at the appliance flue outlet. Factory-built Type HT chimneys have high-temperature thermal shock resistance.

  Circuit Vent. The vent that connects to a horizontal drainage branch and vents two traps to a maximum of eight traps connected into a battery of fixtures. Clarifier. See Interceptor (Clarifier). Clear Water Waste. Cooling water and condensate drainage from refrigeration and air-conditioning equipment; cooled condensate from steam heating systems, and cooled boiler blowdown water.

  Clinical Sink. A fixture that has the same flushing and cleansing characteristics of a water closet that is used to receive the wastes from a bedpan. Also, known as a bedpan washer.

  Clothes Washer System. [HCD 1] A gray water system utilizing only a single domestic clothes washing machine in a one- or two-family dwelling. Coastal High Hazard Areas. An area within the flood hazard area that is subject to high-velocity wave action, and shown on a Flood Insurance Rate Map or other flood hazard map as Zone V, VO, VE or V1-30. Code. A standard that is an extensive compilation of provisions covering broad subject matter or that is suitable for adoption into law independently of other codes and standards. Combination Temperature and Pressure-Relief Valve. A relief valve that actuates when a set temperature, pressure, or both is reached. Also, known as a T&P Valve. Combination Thermostatic/Pressure Balancing Valve. A mixing valve that senses outlet temperature and incoming hot and cold water pressure and compensates for fluctuations in incoming hot and cold water temperatures, pressures, or both to stabilize outlet temperatures. Combination Waste and Vent System. A specially designed system of waste piping embodying the horizontal wet venting of one or more sinks or floor drains using a common waste and vent pipe adequately sized to provide free movement of air above the flow line of the drain.

  2025 CALIFORNIA PLUMBING CODE 33

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  DEFINITIONS

  Combined Building Sewer. See Building Sewer (Combined).

  Combustible Material. A material that, in the form in which it is used and under the conditions anticipated, will ignite and burn; a material that does not meet the definition of noncombustible. [NFPA 54:3.3.64.1]