Sanitary Drainage (Drain, Waste, and Vent)

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

• 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

  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 § 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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  FORMAT OF THE UNIFORM PLUMBING CODE

  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 § 1103.1 Medium relevance — show source text

  (3) Not less than two drains shall be installed in roof areas of 10 000 square feet (929 m [2] ) or less, and not less than one additional drain shall be installed for each 10 000 square feet (929 m [2] ) of roof area exceeding 10 000 square feet (929 m [2] ). (4) Each roof drain shall have a precalibrated, fixed (nonadjustable), and proportional weir (notched) in a standing water collar inside the strainer. No mechanical devices or valves shall be permitted. (5) Pipe sizing shall be based on the pre-calibrated rate of flow (gpm) (L/s) of the pre-calibrated weir for the maximum allowable water depth, and Table 1103.1 and Table 1103.2.

  (6) The height of stones or other granular material above the waterproofed surface shall not be considered in water depth measurement, and the roof surface in the vicinity of the drain shall not be recessed to create a reservoir.

  (7) Roof design, where controlled-flow roof drainage is used, shall be such that the design roof live load is not less than 30 lb/ft [2] (146 kg/m [2] ) to provide a safety factor exceeding the 15 lb/ft [2] (73 kg/m [2] ) represented by the depth of water stored on the roof in accordance with Table 1105.1(1). (8) Scuppers shall be provided in parapet walls. The distance of scupper bottoms above the roof level at the drains shall not exceed the maximum distances specified in Table 1105.1(2).

  (9) Scupper openings shall be not less than 4 inches (102 mm) high and have a width equal to the circumference of

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  STORM DRAINAGE

  the roof drain required for the area served, sized in accordance with Table 1103.1.

  (10)Flashings shall extend above the top of the scuppers.

  (11)At a wall or parapet, 45 degree (0.79 rad) cants shall be installed.

  (12)Separate storm and sanitary drainage systems shall be provided within the building.

  (13)Calculations for the roof drainage system shall be submitted along with the plans to the Authority Having Jurisdiction for approval.

  TABLE 1105.1(1) CONTROLLED-FLOW MAXIMUM ROOF WATER DEPTH

  ROOF RISE* (inches)	MAXIMUM WATER DEPTH AT DRAIN (inches)
  Flat	3
  2	4
  4	5
  6	6

  For SI units: 1 inch = 25.4 mm

  • Vertical measurement from the roof surface at the drain to the highest point of the roof surface served by the drain, ignoring a local depression immediately adjacent to the drain.

  TABLE 1105.1(2) DISTANCE OF SCUPPER BOTTOMS ABOVE ROOF

• CPC § 707.2 Medium relevance — show source text

  For SI units: 1 inch = 25 mm

  707.2 Approved. Each cleanout fitting and each cleanout plug or cap shall be of an approved type. A list of approved standards for cleanouts are referenced in Table 707.2.

  TABLE 707.2 CLEANOUT MATERIALS FOR DRAIN, WASTE, AND VENT

  MATERIAL	STANDARD
  ABS_1_	ASTM D2661, CSA B79, IAPMO IGC 78, IAPMO IGC 224
  Cast Iron	ASME A112.36.2M, ASTM A888, CISPI 301, CSA B79, IAPMO IGC 224
  Copper or Copper Alloy	ASME A112.36.2M, CSA B79
  Ductile Iron	CSA B79
  Elastomers	CSA B79, IAPMO PS 90
  Polyethylene (PE)	CSA B79
  Polypropylene (PP)	CSA B79
  PVC_1_	ASTM D2665, CSA B79, IAPMO IGC 78, IAPMO IGC 224
  Polyvinylidene Fluoride (PVDF)	CSA B79
  Stainless Steel	CSA B79

  1 [HCD 1 & HCD 2] ABS and PVC installations are limited to not more

  than two stories of areas of residential accommodation.

  707.3 Watertight and Gastight. Cleanouts shall be designed to be watertight and gastight. 707.4 Location. Each horizontal drainage pipe shall be provided with a cleanout at its upper terminal, and each run of piping, that is more than 100 feet (30 480 mm) in total developed length, shall be provided with a cleanout for each 100 feet (30 480 mm), or fraction thereof, in length of such piping. An additional cleanout shall be provided in a drainage line for each aggregate horizontal change in direction exceeding 135 degrees (2.36 rad). A cleanout shall be installed above the fixture connection fitting, serving each urinal, regardless of the location of the urinal in the building.

  TABLE 707.1

  CLEANOUTS

  For SI units: 1 inch = 25 mm

  TABLE 707.2 CLEANOUT MATERIALS FOR DRAIN, WASTE, AND VENT

  1 [HCD 1 & HCD 2] ABS and PVC installations are limited to not more

  than two stories of areas of residential accommodation.

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  SANITARY DRAINAGE

  Exceptions:

  (1) Cleanouts shall be permitted to be omitted on a horizontal drain line less than 5 feet (1524 mm) in length unless such line is serving sinks or urinals.

  (2) Cleanouts shall be permitted to be omitted on a horizontal drainage pipe installed on a slope of 72 degrees (1.26 rad) or less from the vertical angle (one-fifth bend).

• CPC § 705.10 Medium relevance — show source text

  Waste,
  and Vent (DWV), Sewer, Sanitary, and Storm Plumbing Sys-
  tems for Above and Below Ground Use|Joints|705.10|

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  REFERENCED STANDARDS

  TABLE 1701.1 (continued) REFERENCED STANDARDS

  STANDARD NUMBER	STANDARD TITLE	APPLICATION	REFERENCED SECTION
  ASTM C1540-2020	Standard Specification for Heavy-Duty Shielded Couplings Joining Hubless Cast Iron Soil Pipe and Fittings	Joints	705.2.2
  ASTM C1563-2008 (R2021)	Standard Test Method for Gaskets for Use in Connection with Hub and Spigot Cast Iron Soil Pipe and Fittings for Sanitary Drain, Waste, Vent, and Storm Piping Applications	Joints	705.2.2
  ASTM C1822-2021	Standard Specification for Insulating Covers on Accessible Lavatory Piping	Miscellaneous	403.3
  ASTM D1253-2014	Standard Test Method for Residual Chlorine in Water	Miscellaneous	1506.10.6, 1603.4.1
  ASTM D1785-2021a	Standard Specification for Poly (Vinyl Chloride) (PVC) Plastic Pipe, Schedules 40, 80, and 120	Piping	Table 604.1, Table 701.2
  ASTM D2235-2021	Standard Specification for Solvent Cement for Acrylonitrile- Butadiene-Styrene (ABS) Plastic Pipe and Fittings	Joints	705.1.2
  ASTM D2239-2021	Standard Specification for Polyethylene (PE) Plastic Pipe (SIDR-PR) Based on Controlled Inside Diameter	Piping	Table 604.1
  ASTM D2241-2020	Standard Specification for Poly (Vinyl Chloride) (PVC) Pressure- Rated Pipe (SDR Series)	Piping	Table 604.1
  ASTM D2464-2015	Standard Specification for Threaded Poly (Vinyl Chloride) (PVC) Plastic Pipe Fittings, Schedule 80	Fittings	Table 604.1
  ASTM D2466-2021	Standard Specification for Poly (Vinyl Chloride) (PVC) Plastic Pipe Fittings, Schedule 40	Fittings	Table 604.1
  ASTM D2467-2020	Standard Specification for Poly (Vinyl Chloride) (PVC) Plastic Pipe Fittings, Schedule 80	Fittings	Table 604.1
  ASTM D2513-2020	Standard Specification for Polyethylene (PE) Gas Pressure Pipe, Tubing, and Fittings	Piping	1208.5.4, 1208.5.6.2, 1208.5.10.2, 1210.1.7.1(1)
  ASTM D2564-2020	Standard Specification for Solvent Cements for Poly (Vinyl Chloride) (PVC) Plastic Piping Systems	Joints	605.12.2, 705.6.

• CPC § 1.4 Medium relevance — show source text

  1.4, 705.3.3| |ASTM C4-2004 (R2018)|Standard Specification for Clay Drain Tile and Perforated Clay
  Drain Tile|Piping|Table 1101.4.6| |ASTM C425-2021|Standard Specification for Compression Joints for Vitrified
  Clay Pipe and Fittings|Joints|705.8.1| |ASTM C564-2020a|Standard Specification for Rubber Gaskets for Cast Iron Soil
  Pipe and Fittings|Joints|705.2.2| |ASTM C700-2018|Standard Specification for Vitrified Clay Pipe, Extra Strength,
  Standard Strength, and Perforated|Piping|Table 701.2,
  Table 1101.4.6| |ASTM C1053-2000 (R2015)|Standard Specification for Borosilicate Glass Pipe and Fittings
  for Drain, Waste, and Vent (DWV) Applications|Piping|811.2| |ASTM C1173-2018|Standard Specification for Flexible Transition Couplings for
  Underground Piping Systems|Fittings|705.10| |ASTM C1277-2020|Standard Specification for Shielded Couplings Joining Hubless
  Cast Iron Soil Pipe and Fittings|Fixtures|301.2.4, 705.2.2| |ASTM C1460-2021|Standard Specification for Shielded Transition Couplings for
  Use With Dissimilar DWV Pipe and Fittings Above Ground|Joints|705.10| |ASTM C1461-2021|Standard Specification for Mechanical Couplings Using Ther-
  moplastic Elastomeric (TPE) Gaskets for Joining Drain, Waste,
  and Vent (DWV), Sewer, Sanitary, and Storm Plumbing Sys-
  tems for Above and Below Ground Use|Joints|705.10|

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  REFERENCED STANDARDS

  TABLE 1701.1 (continued) REFERENCED STANDARDS

  STANDARD NUMBER	STANDARD TITLE	APPLICATION	REFERENCED SECTION
  ASTM C1540-2020	Standard Specification for Heavy-Duty Shielded Couplings Joining Hubless Cast Iron Soil Pipe and Fittings	Joints	705.2.2
  ASTM C1563-2008 (R2021)	Standard Test Method for Gaskets for Use in Connection with Hub and Spigot Cast Iron Soil Pipe and Fittings for Sanitary Drain, Waste, Vent, and Storm Piping Applications	Joints	705.2.2
  ASTM C1822-2021	Standard Specification for Insulating Covers on Accessible Lavatory Piping	Miscellaneous	403.3
  ASTM D1253-2014	Standard Test Method for Residual Chlorine in Water	Miscellaneous	1506.10.6, 1603.4.1
  ASTM D1785-2021a	Standard Specification for Poly (Vinyl Chloride) (PVC) Plastic Pipe, Schedules 40, 80, and 120	Piping	Table 604.1, Table 701.

• CPC § 910.7 Medium 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 § 0.06 Medium relevance — show source text

  INTERMITTENT FLOW ONLY*

  GPM	FIXTURE UNITS
  Up to 71⁄2	Equals 1 Fixture Unit
  Greater than 71⁄2 to 15	Equals 2 Fixture Units
  Greater than 15 to 30	Equals 4 Fixture Units
  Greater than 30 to 50	Equals 6 Fixture Units

  For SI units: 1 gallon per minute = 0.06 L/s

  • Discharge capacity exceeding 50 gallons per minute (3.15 L/s) shall be determined by the Authority Having Jurisdiction.

  702.3 Continuous Flow. For a continuous flow into a drainage system, such as from a pump, sump ejector, air conditioning equipment, or similar device, 2 fixture units shall be equal to each gallon per minute (gpm) (L/s) of flow.

  703.0 Size of Drainage Piping. 703.1 Minimum Size. The minimum sizes of vertical, horizontal, or both drainage piping shall be determined from the total of fixture units connected thereto, and additionally, in the case of vertical drainage pipes, in accordance with their length.

  703.2 Maximum Number of Fixture Units. Table 703.2

  shows the maximum number of fixture units allowed on a vertical or horizontal drainage pipe, building drain, or building sewer of a given size; the maximum number of fixture units allowed on a branch interval of a given size; and the maximum length (in feet and meters) of a vertical drainage pipe of a given size. 703.3 Sizing per Appendix C. For alternate method of sizing drainage piping, see Appendix C.

  704.0 Fixture Connections (Drainage). 704.1 Inlet Fittings. Drainage piping shall be provided with approved inlet fittings for fixture connections, correctly located according to the size and type of fixture proposed to be connected.

  704.2 Single Vertical Drainage Pipe. Two fixtures set back-to-back, or side-by-side, within the distance allowed between a trap and its vent, shall be permitted to be served by a single vertical drainage pipe provided that each fixture wastes separately into an approved double-fixture fitting having inlet openings at the same level. 704.3 Commercial Sinks. Pot sinks, scullery sinks, dishwashing sinks, silverware sinks, and other similar fixtures shall be connected directly to the drainage system. A floor drain shall be provided adjacent to the fixture and shall be connected on the sewer side of the sink. No other drainage

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  SANITARY DRAINAGE

  TABLE 703.2

  MAXIMUM UNIT LOADING AND MAXIMUM LENGTH OF DRAINAGE AND VENT PIPING

  SIZE OF PIPE (inches)	11⁄4	11⁄2	2	3	4	5	6	8	10	12
  Maximum Units Drainage Piping1 Vertical Horizontal	1 1	22,

• CPC § 18001.8 Medium relevance — show source text

  Branch. A part of the piping system other than a main, riser, or stack.

  Branch, Fixture. See Fixture Branch.

  Branch, Horizontal. See Horizontal Branch.

  Branch Vent. A vent connecting one or more individual vents with a vent stack or stack vent.

  Building. A structure built, erected, and framed of component structural parts designed for the housing, shelter, enclosure, or support of persons, animals, or property of any kind. Exceptions: [HCD 1 & HCD 2] “BUILDING” shall not include the following:

  1. Any mobilehome as defined in Health and Safety Code Section 18008.

  2. Any manufactured home as defined in Health and Safety Code Section 18007.

  3. Any commercial modular as defined in Health and Safety Code Section 18001.8 or any special purpose commer- cial modular as defined in Section 18012.5.

  4. Any recreational vehicle as defined in Health and Safety Code Section 18010.

  5. Any multifamily manufactured home as defined in Health and Safety Code Section 18008.7.

  For additional information, see Health and Safety Code Section 18908.

  Building Drain. That part of the lowest piping of a drainage system that receives the discharge from soil, waste, and other drainage pipes inside the walls of the building and conveys it to the building sewer beginning 2 feet (610 mm) outside the building wall. Building Drain (Sanitary). A building drain that conveys sewage only. Building Drain (Storm). A building drain that conveys storm water or another drainage, but no sewage. Building Sewer. That part of the horizontal piping of a drainage system that extends from the end of the building drain and that receives the discharge of the building drain and conveys it to a public sewer, private sewer, private sewage disposal system, or another point of disposal. Building Sewer (Combined). A building sewer that conveys both sewage and storm water or other drainage.

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  DEFINITIONS

  Building Sewer (Sanitary). A building sewer that conveys sewage only. Building Sewer (Storm). A building sewer that conveys storm water or another drainage, but no sewage. Building Subdrain. That portion of a drainage system that does not drain by gravity into the building sewer. Building Supply. The pipe is carrying potable water from the water meter or another source of water supply to a building or other point of use or distribution on the lot.

  205.0 – C –

  Category 1. Activities, systems, or equipment whose failure is likely to cause major injury or death to patients, staff, or visitors. [NFPA 99:3.3.162.1] Category 2. Activities, systems, or equipment whose failure is likely to cause minor injury to patients, staff, or visitors.

  [NFPA 99:3.3.162.2] Category 3. Activities, systems, or equipment whose failure is not likely to cause injury to patients, staff, or visitors, but can cause discomfort. [NFPA 99:3.3.162.3] **Category 3 Vacuum System.

• CPC § 701.2 Medium relevance — show source text

  SANITARY DRAINAGE

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

  MATERIAL	UNDERGROUND DRAIN, WASTE, VENT PIPE AND FITTINGS	ABOVEGROUND DRAIN, WASTE, VENT PIPE AND FITTINGS	BUILDING SEWER PIPE AND FITTINGS	REFERENCED STAN- DARD(S) PIPE	REFERENCED STANDARD(S) FITTINGS
  ABS (Schedule 40)	X	X	X	ASTM D2661, ASTM D2680*	ASME A112.4.4, ASTM D2661, ASTM D2680*
  Cast-Iron	X	X	X	ASTM A74, ASTM A888, CISPI 301	ASME B16.12, ASTM A74, ASTM A888, CISPI 301
  Co-Extruded ABS (Schedule 40)	X	X	X	ASTM F628	ASME A112.4.4, ASTM D2661, ASTM D2680*
  Co-Extruded Composite (Schedule 40)	X	X	X	ASTM F1488	ASME A112.4.4, ASTM D2661, ASTM D2665, ASTM F794*, ASTM F1866
  Co-Extruded PVC (Schedule 40)	X	X	X	ASTM F891, ASTM F1760	ASME A112.4.4, ASTM D2665, ASTM F794*****, ASTM F1336***,** ASTM F1866
  Copper and Copper Alloys (Type DWV)	X	X	X	ASTM B43, ASTM B75, ASTM B251, ASTM B302, ASTM B306	ASME B16.23, ASME B16.29
  Galvanized Malleable Iron	––	X	––	––	ASME B16.3
  Galvanized Steel	––	X	––	ASTM A53	––
  Polyethylene	––	––	X	ASTM F714, ASTM F894	––
  PVC (Schedule 40)	X	X	X	ASTM D1785, ASTM D2665, ASTM F794*	ASME A112.4.4, ASTM D2665, ASTM F794*, ASTM F1866
  PVC (Sewer and Drain)	––	––	X	ASTM D2729	ASTM D2729
  PVC PSM	––	––	X	ASTM D3034	ASTM D3034
  Stainless Steel 304	––	X	––	ASME A112.3.1	ASME A112.3.1
  Stainless Steel 316L	X	X	X	ASME A112.3.1	ASME A112.3.1
  Vitrified Clay (Extra strength)	––	––	X	ASTM C700	ASTM C700

  • For building sewer applications.

  166 2025 CALIFORNIA PLUMBING CODE

• CPC § 3.3.74 Medium relevance — show source text

  a. Shall be designed and installed to prevent splashing outside of the lavatory.

  b. Shall be well-fitted and sealed to prevent water leaks onto or into the cabinetry or wall spaces.

  c. Design of lavatories and cabinetry shall not permit storage beneath the fixture basin.

  d. Shall be constructed of nonporous material. Hangers. See Supports. Health Care Facility’s Governing Body. The person or persons who have the overall legal responsibility for the operation of a health care facility. [NFPA 99:3.3.74] High Hazard. See Contamination. Horizontal Branch. A drainpipe extending laterally from soil or waste stack or building drain with or without vertical sections or branches, which receives the discharge from one or more fixture drains and conducts it to the soil or waste stack or the building drain. Horizontal Pipe. A pipe or fitting that is installed in a horizontal position or which makes an angle of less than 45 degrees (0.79 rad) with the horizontal.

  Hot Water. Water at a temperature exceeding or equal to 120°F (49°C). House Drain. See Building Drain. House Sewer. See Building Sewer. Hydromechanical Grease Interceptor. A plumbing appurtenance or appliance that is installed in a sanitary drainage system to intercept nonpetroleum fats, oil, and

  grease (FOG) from a wastewater discharge and is identified by flow rate, and separation and retention efficiency. The design incorporates air entrainment, hydromechanical separation, interior baffling, or barriers in combination or separately, and one of the following:

  (1) External flow control, with an air intake (vent), directly connected.

  (2) External flow control, without air intake (vent), directly connected.

  (3) Without external flow control, directly connected.

  (4) Without external flow control, indirectly connected.

  These interceptors comply with the requirements of Table 1014.2.1. Hydromechanical grease interceptors are generally installed inside.

  211.0 – I –

  Indirect-Fired Water Heater. A water heater consisting of a storage tank equipped with an internal or external heat exchanger used to transfer heat from an external source to heat potable water. The storage tank either contains heated potable water or water supplied from an external source, such as a boiler.

  Indirect Waste Pipe. A pipe that does not connect directly to the drainage system but conveys liquid wastes by discharging into a plumbing fixture, interceptor, or receptacle that is directly connected to the drainage system.

  Individual Vent. A pipe installed to vent a fixture trap, and that connects with the vent system above the fixture served or terminates in the open air.

  Industrial Waste. Liquid or water-borne waste from industrial or commercial processes, except domestic sewage.

  Insanitary. A condition that is contrary to sanitary principles or is injurious to health.

  Conditions to which “insanitary” shall apply include the following:

  (1) A trap that does not maintain a proper trap seal.

  (2) An opening in a drainage system, except where lawful that is not provided with an approved liquid-sealed trap.

  (3) A plumbing fixture or other waste discharging receptor or device that is not supplied with water sufficient to flush and maintain the fixture or receptor in a clean condition.

  (4) A defective fixture, trap, pipe, or fitting.