Wet venting, circuit venting and special fixtures

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

• CPC § 904.0. High relevance — show source text

  VENTS

  smaller than the minimum vent pipe size required for a fixture served, or by Section 904.0. 908.2 Horizontal Wet Venting for a Bathroom Group. A bathroom group located on the same floor level shall be permitted to be vented by a horizontal wet vent where all of the conditions of Section 908.2.1 through Section 908.2.5 are met.

  908.2.1 Vent Connection. The dry vent connection to the wet vent shall be an individual vent for the bidet, shower, or bathtub. One or two vented lavatory(s) shall be permitted to serve as a wet vent for a bathroom group. Only one wet-vented fixture drain or trap arm shall discharge upstream of the dry-vented fixture drain connection. Dry vent connections to the horizontal wet vent shall be in accordance with Section 905.2 and Section

  905.3.

  908.2.2 Size. The wet vent shall be sized based on the fixture unit discharge into the wet vent. The wet vent shall be not less than 2 inches (50 mm) in diameter for 4 drainage fixture units (dfu) or less, and not less than 3 inches (80 mm) in diameter for 5 dfu or more. The dry vent shall be sized in accordance with Table 702.1 and Table 703.2 based on the total fixture units discharging into the wet vent.

  908.2.3 Trap Arm. The length of the trap arm shall not exceed the limits in Table 1002.2. The trap size shall be in accordance with Section 1003.3. The vent pipe opening from the horizontal wet vent, except for water closets and similar fixtures, shall not be below the weir of the trap.

  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

• 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

  2025 CALIFORNIA PLUMBING CODE 191

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

  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 § 906.4 High relevance — show source text

  906.4 Outdoor Installations. Vent pipes for outdoor installations shall extend not less than 10 feet (3048 mm) above the surrounding ground and shall be securely supported.

  906.5 Joints. Joints at the roof around vent pipes shall be made watertight by the use of approved flashings or flashing material.

  906.6 Lead. (See Chapter 17) Sheet lead shall comply with the following:

  (1) For safe pans – not less than 4 pounds per square foot (lb/ft [2] ) (19 kg/m [2] ) or [1] ⁄ 16 of an inch (1.6 mm) thick. (2) For flashings or vent terminals – not less than 3 lb/ft [2] (15 kg/m [2] ) or 0.0472 of an inch (1.2 mm) thick. (3) Lead bends and lead traps shall be not less than [1] ⁄ 8 of an inch (3.2 mm) in wall thickness.

  906.7 Frost or Snow Closure. Where frost or snow closure is likely to occur in locations having minimum design temperature below 0°F (-17.8°C), vent terminals shall be not less than 3 inches (76 mm) in diameter, but in no event smaller than the required vent pipe. The change in diameter shall be made inside the building not less than 1 foot (305 mm) below the roof in an insulated space and terminate not less than 10 inches (254 mm) above the roof, or in accordance with the Authority Having Jurisdiction.

  907.0 Vent Stacks and Relief Vents.

  907.1 Drainage Stack. Each drainage stack that extends 10 or more stories shall be served by a parallel vent stack, which shall extend undiminished in size from its upper terminal and connect to the drainage stack at or immediately below the lowest fixture drain. Each such vent stack shall also be connected to the drainage stack at each fifth floor, counting down from the uppermost fixture drain, using a yoke vent, the size of which shall be not less in diameter than either the drainage or the vent stack, whichever is smaller.

  907.2 Yoke Vent. The yoke vent connection to the vent stack shall be placed not less than 42 inches (1067 mm) above the floor level, and the yoke vent connection to the drainage stack shall be using a wye-branch fitting placed below the lowest drainage branch connection serving that floor.

  908.0 Wet Venting. 908.1 Vertical Wet Venting. Wet venting is limited to vertical drainage piping receiving the discharge from the trap arm of one and two fixture unit fixtures that also serves as a vent not exceeding four fixtures. Wet-vented fixtures shall be within the same story; provided, further, that fixtures with a continuous vent discharging into a wet vent shall be within the same story as the wet-vented fixtures. No wet vent shall exceed 6 feet (1829 mm) in developed length. 908.1.1 Size. The vertical piping between two consecutive inlet levels shall be considered a wet-vented sec tion. Each wet-vented section shall be not less than one pipe size exceeding the required minimum waste pipe size of the upper fixture or shall be one pipe size exceeding the required minimum pipe size for the sum of the fixture units served by such wet-vented section, whichever is larger, but in no case less than 2 inches (50 mm) in diameter. **908.1.2 Vent Connection.

• 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

  2025 CALIFORNIA PLUMBING CODE 191

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

  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 § 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 § 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.

  2025 CALIFORNIA PLUMBING CODE xv

• CPC § 905.1 Medium 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

  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.

  2025 CALIFORNIA PLUMBING CODE xv

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

  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 § 605.1.3.1 Medium relevance — show source text

  605.1.3.1, 605.1.4, 605.16.1,

  705.3.3, 705.10.1, 705.10.2

  SPACING

  Pipe supports . . . . . . . . . . . .313.0, Table 313.3, 1210.3.5,

  1210.3.5.1, Table 1210.3.5.1,

  1323.4, Table 1323.4.4,

  1327.6, Table 1327.6

  Subsoil irrigation fields . . . . . . . . . . . . . . . . . . .1504.7.3 Trenching and leaching beds . . . . . . . . . . . . . . .H 601.9

  SPECIAL FIXTURES . . . . . . . . . . . . . . . . . . . . . . . . . .406.0

  SPECIAL VENTING . . . . . . . . . . . . . . . . . . . . . . . . . . .909.0

  SPECIAL WASTE PIPE . . . . . . . . . .(see Industrial wastes)

  SPECIAL WASTES

  Acid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .811.2

  Chemical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .811.0

  Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .221.0

  Industrial . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .811.0

  High temperatures . . . . . . . . . . . . . . .810.1, Table 810.1 Laundries, slaughterhouses, bottling establishments,

  and auto wash racks . . . . . . . .711.0, 1010.0 – 1013.0

  SPECIFIC GRAVITY,

  NATURAL GAS . . . . . . . . . . . . . . . . . . . . . . . . . . .1214.1

  SPECIFICATIONS

  FOR MATERIALS . . . . . . . . . . . . . . . . . .301.2, Table 1701.1

  STACKS . . . . . . . . . . . . . .221.0, 317.1, 706.2, 711.1, 906.1,

  907.0, 911.3, 1101.16.2, C 304.3,

  C 304.4, C 401.0, C 601.0

  STAINLESS STEEL PIPE . . . . . . .Table 313.3, Table 604.1,

  605.13, Table 701.2, 705.7

  STANDPIPE,

  CLOTHES WASHER . . . . . . . . . . . . . . . . . . . . . . . . .804.1

  STATION INLETS

• CPC § 907.2 Medium relevance — show source text

  907.2 Yoke Vent. The yoke vent connection to the vent stack shall be placed not less than 42 inches (1067 mm) above the floor level, and the yoke vent connection to the drainage stack shall be using a wye-branch fitting placed below the lowest drainage branch connection serving that floor.

  908.0 Wet Venting. 908.1 Vertical Wet Venting. Wet venting is limited to vertical drainage piping receiving the discharge from the trap arm of one and two fixture unit fixtures that also serves as a vent not exceeding four fixtures. Wet-vented fixtures shall be within the same story; provided, further, that fixtures with a continuous vent discharging into a wet vent shall be within the same story as the wet-vented fixtures. No wet vent shall exceed 6 feet (1829 mm) in developed length. 908.1.1 Size. The vertical piping between two consecutive inlet levels shall be considered a wet-vented sec tion. Each wet-vented section shall be not less than one pipe size exceeding the required minimum waste pipe size of the upper fixture or shall be one pipe size exceeding the required minimum pipe size for the sum of the fixture units served by such wet-vented section, whichever is larger, but in no case less than 2 inches (50 mm) in diameter. 908.1.2 Vent Connection. Common vent sizing shall be the sum of the fixture units served but, in no case,

  190 2025 CALIFORNIA PLUMBING CODE

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  VENTS

  smaller than the minimum vent pipe size required for a fixture served, or by Section 904.0. 908.2 Horizontal Wet Venting for a Bathroom Group. A bathroom group located on the same floor level shall be permitted to be vented by a horizontal wet vent where all of the conditions of Section 908.2.1 through Section 908.2.5 are met.

  908.2.1 Vent Connection. The dry vent connection to the wet vent shall be an individual vent for the bidet, shower, or bathtub. One or two vented lavatory(s) shall be permitted to serve as a wet vent for a bathroom group. Only one wet-vented fixture drain or trap arm shall discharge upstream of the dry-vented fixture drain connection. Dry vent connections to the horizontal wet vent shall be in accordance with Section 905.2 and Section

  905.3.

  908.2.2 Size. The wet vent shall be sized based on the fixture unit discharge into the wet vent. The wet vent shall be not less than 2 inches (50 mm) in diameter for 4 drainage fixture units (dfu) or less, and not less than 3 inches (80 mm) in diameter for 5 dfu or more. The dry vent shall be sized in accordance with Table 702.1 and Table 703.2 based on the total fixture units discharging into the wet vent.

  908.2.3 Trap Arm. The length of the trap arm shall not exceed the limits in Table 1002.2. The trap size shall be in accordance with Section 1003.3. The vent pipe opening from the horizontal wet vent, except for water closets and similar fixtures, shall not be below the weir of the trap.

• CPC § 7.3 Medium relevance — show source text

  3|7.3|9.9|14.6| |26|NP|NP|NP|NP|13.2|22.4|NP|NP|5.0|8.5|11.4|16.9| |28|NP|NP|NP|NP|15.1|25.7|NP|NP|5.7|9.7|13.1|19.4| |30|NP|NP|NP|NP|17.2|NP|NP|NP|6.5|11.0|14.9|22.0| |32|NP|NP|NP|NP|19.4|NP|NP|NP|7.3|12.4|16.8|24.8| |34|NP|NP|NP|NP|21.7|NP|NP|NP|8.2|13.9|18.8|NP| |36|NP|NP|NP|NP|24.1|NP|NP|NP|9.1|15.4|20.9|NP| |For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 gallon per minute = 0.063 L/s, 1 pound per square inch = 6.895 kPa.
  NP = Not Permitted. Pressure loss exceeds reasonable limits.
  a. Values are applicable for underground piping materials listed in_ the California Plumbing Code_ and are based on an SDR of 11 and a Hazen Williams C Factor of 150.
  b. Values include the following length allowances for fittings: 25-percent length increase for actual lengths up to 100 feet and 15-percent length increase for actual lengths over
  100 feet.
  c. Flow rate from Section P2904.4.2. Add 5 gpm to the flow rate required by Section_R309.3.4.2_ where the water service pipe supplies more than one dwelling.|For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 gallon per minute = 0.063 L/s, 1 pound per square inch = 6.895 kPa.
  NP = Not Permitted. Pressure loss exceeds reasonable limits.
  a. Values are applicable for underground piping materials listed in_ the California Plumbing Code_ and are based on an SDR of 11 and a Hazen Williams C Factor of 150.
  b. Values include the following length allowances for fittings: 25-percent length increase for actual lengths up to 100 feet and 15-percent length increase for actual lengths over
  100 feet.
  c. Flow rate from Section P2904.4.2. Add 5 gpm to the flow rate required by Section_R309.3.4.2_ where the water service pipe supplies more than one dwelling.|For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 gallon per minute = 0.063 L/s, 1 pound per square inch = 6.895 kPa.
  NP = Not Permitted. Pressure loss exceeds reasonable limits.
  a. Values are applicable for underground piping materials listed in_ the California Plumbing Code_ and are based on an SDR of 11 and a Hazen Williams C Factor of 150.
  b. Values include the following length allowances for fittings: 25-percent length increase for actual lengths up to 100 feet and 15-percent length increase for actual lengths over
  100 feet.
  c. Flow rate from Section P2904.4.2.