Trap seals, floor drains and primers

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

• CPC § 1004.2 High relevance — show source text

  1004.2 Movable Parts. Bladders, check valves or another type of devices with moveable parts shall be prohibited to serve as a trap.

  1005.0 Trap Seals. 1005.1 General. Each fixture trap shall have a liquid seal of not less than 2 inches (51 mm) and not more than 4 inches (102 mm), except where a deeper seal is found necessary by the Authority Having Jurisdiction. Traps shall be set true with respect to their liquid seals and, where necessary, they shall be protected from freezing.

  1006.0 Floor Drain Traps. 1006.1 General. Floor drains shall connect into a trap so constructed that it can be readily cleaned and of a size to serve efficiently the purpose for which it is intended. The drain inlet shall be so located that it is in full view. Where subject to the reverse flow of sewage or liquid waste, such drains shall be equipped with an approved backwater valve.

  1007.0 Trap Seal Protection. 1007.1 General. Floor drain or similar traps directly connected to the drainage system and subject to infrequent use shall be protected with a trap seal primer, except where not deemed necessary for safety or sanitation by the Authority Having Jurisdiction. Trap seal primers shall be accessible for maintenance.

  1007.2 Trap Seal Primers. Potable water supply trap seal primer valves shall comply with ASSE 1018. Drainage or electronic design type trap seal primer devices shall comply with ASSE 1044 or IAPMO PS 76.

  1008.0 Building Traps. 1008.1 General. Building traps shall not be installed except where required by the Authority Having Jurisdiction. Each building trap where installed shall be provided with a cleanout and with a relieving vent or fresh-air intake on the inlet side of the trap, which needs not be larger than one-half the diameter of the drain to which it connects. Such relieving vent or fresh-air intake shall be carried above grade and terminate in a screened outlet located outside the building.

  1009.0 Interceptors (Clarifiers) and Separators.

  1009.1 Where Required. Interceptors (clarifiers) (including grease, oil, sand, solid interceptors, etc.) shall be required

  by the Authority Having Jurisdiction where they are necessary for the proper handling of liquid wastes containing grease, flammable wastes, sand, solids, acid or alkaline substances, or other ingredients harmful to the building drainage system, the public or private sewer, or to public or private sewage disposal. A list of acceptable interceptor standards is referenced in Table 1009.1.

  TABLE 1009.1 APPROVED INTERCEPTORS (CLARIFIERS)

• CPC § 25.4 High relevance — show source text

  For SI units: 1 inch = 25.4 mm

  Notes: 1 Maintain 1 ⁄ 4 inch per foot slope (20.8 mm/m). 2 The developed length between the trap of a water closet or similar fixture (measured from the face of the closet flange to the inner edge of the vent) and its vent shall not exceed 6 feet (1829 mm). 3 Horizontally wet vented bathtubs, showers and similar fixtures shall be limited to a maximum of 6 feet (1829 mm) for 1½ inch (40 mm) fixture drains and 8 feet (2438 mm) for 2 inch (50 mm) fixture drains, maintaining ¼ inch per foot slope (20.8 mm/m).

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  TRAPS AND INTERCEPTORS

  1004.0 Traps.

  1004.1 Prohibited. No form of trap that depends for its seal upon the action of movable parts shall be used. No trap that has concealed interior partitions, except those of plastic, glass, or similar corrosion-resisting material, shall be used. “S” traps, bell traps, and crown-vented traps shall be prohibited. No fixture shall be double trapped. Drum and bottle traps shall be installed for special conditions. No trap shall be installed without a vent, except as otherwise provided in this code.

  1004.2 Movable Parts. Bladders, check valves or another type of devices with moveable parts shall be prohibited to serve as a trap.

  1005.0 Trap Seals. 1005.1 General. Each fixture trap shall have a liquid seal of not less than 2 inches (51 mm) and not more than 4 inches (102 mm), except where a deeper seal is found necessary by the Authority Having Jurisdiction. Traps shall be set true with respect to their liquid seals and, where necessary, they shall be protected from freezing.

  1006.0 Floor Drain Traps. 1006.1 General. Floor drains shall connect into a trap so constructed that it can be readily cleaned and of a size to serve efficiently the purpose for which it is intended. The drain inlet shall be so located that it is in full view. Where subject to the reverse flow of sewage or liquid waste, such drains shall be equipped with an approved backwater valve.

  1007.0 Trap Seal Protection. 1007.1 General. Floor drain or similar traps directly connected to the drainage system and subject to infrequent use shall be protected with a trap seal primer, except where not deemed necessary for safety or sanitation by the Authority Having Jurisdiction. Trap seal primers shall be accessible for maintenance.

  1007.2 Trap Seal Primers. Potable water supply trap seal primer valves shall comply with ASSE 1018. Drainage or electronic design type trap seal primer devices shall comply with ASSE 1044 or IAPMO PS 76.

• CPC § 1003.2 High relevance — show source text

  1003.2 Slip Joint Fittings . . . . . . . . . . . . .195

  1003.3 Size . . . . . . . . . . . . . . . . . . . . . . . .195

  1004.0 Traps . . . . . . . . . . . . . . . . . . . . . .196

  1004.1 Prohibited . . . . . . . . . . . . . . . . . . .196

  1004.2 Movable Parts . . . . . . . . . . . . . . . .196

  1005.0 Trap Seals . . . . . . . . . . . . . . . . . .196

  1005.1 General . . . . . . . . . . . . . . . . . . . . .196

  1006.0 Floor Drain Traps . . . . . . . . . . . . .196

  1006.1 General . . . . . . . . . . . . . . . . . . . . .196

  1007.0 Trap Seal Protection . . . . . . . . . . .196

  1007.1 General . . . . . . . . . . . . . . . . . . . . .196

  1007.2 Trap Seal Primers . . . . . . . . . . . .196

  1008.0 Building Traps . . . . . . . . . . . . . . . .196

  1008.1 General . . . . . . . . . . . . . . . . . . . . .196

  1009.0 Interceptors (Clarifiers) and Separators . . . . . . . . . . . . . . . . . .196

  1009.1 Where Required . . . . . . . . . . . . . .196

  Table 1009.1 Approved Interceptors (Clarifiers) . .196

  1009.2 Approval . . . . . . . . . . . . . . . . . . . .196

  1009.3 Design . . . . . . . . . . . . . . . . . . . . .196

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  TABLE OF CONTENTS

  1009.4 Relief Vent . . . . . . . . . . . . . . . . . .196

  1009.5 Location . . . . . . . . . . . . . . . . . . . .196

  1009.6 Maintenance of Interceptors . . . . .196

  1009.7 Discharge . . . . . . . . . . . . . . . . . . .196

  1010.0 Slaughterhouses, Packing Establishments, etc . . . . . . . . . . .196

  1010.1 General . . . . . . . . . . . . . . . . . . . . .196

  1010.2 Meat and Poultry Processing Plants . . . . . . . . . . . . . . . . . . . . . .197

  1010.3 Collection Centers and

  Facilities . . . . . . . . . . . . . . . . . . . .197

  1010.4 Horse Meat and Pet Food

• CPC § 2.9 Medium relevance — show source text

  [MP] TRAP. A fitting, either separate or built into a fixture, that provides a liquid seal to prevent the emission of sewer gases without materially affecting the flow of sewage or wastewater through it.

  [MP] TRAP ARM. That portion of a fixture drain between a trap weir and the vent fitting.

  [MP] TRAP PRIMER. A device or system of piping to maintain a water seal in a trap, typically installed where infrequent use of the trap would result in evaporation of the trap seal, such as floor drains.

  [MP] TRAP SEAL. The trap seal is the maximum vertical depth of liquid that a trap will retain, measured between the crown weir and the top of the dip of the trap.

  [RB] TRIM. Picture molds, chair rails, baseboards, handrails, door and window frames, and similar decorative or protective materials used in fixed applications.

  [RB] TRUSS DESIGN DRAWING. The graphic depiction of an individual truss, that describes the design and physical characteristics of the truss.

  [RB] TUBULAR DAYLIGHTING DEVICE (TDD). A nonoperable fenestration unit primarily designed to transmit daylight from a roof surface to an interior ceiling via a tubular conduit. The basic unit consists of an exterior glazed weathering surface, a light-transmitting tube with a reflective interior surface, and an interior-sealing device such as a translucent ceiling panel. The unit may be factory assembled, or field assembled from a manufactured kit.

  [MP] TYPE L VENT. A listed and labeled vent conforming to UL 641 for venting oil-burning appliances listed for use with Type L vents or with gas appliances listed for use with Type B vents.

  [RB] TYPE X. A type of gypsum panel product with special core additives to increase the fire resistance as specified by the applicable standards listed in Section R702.3 (see the definition of “Gypsum panel product”).

  [RB] UNDERLAYMENT. One or more layers of felt, sheathing paper, nonbituminous saturated felt, or other approved material over which a roof covering, with a slope of 2 units vertical in 12 units horizontal (17-percent slope) or greater, is applied.

  [MP] VACUUM BREAKER. A device that prevents back-siphonage of water by admitting atmospheric pressure through ports to the discharge side of the device.

  [RB] VAPOR DIFFUSION PORT. An assembly constructed or installed within a roof assembly at an opening in the roof deck to convey water vapor from an unvented attic to the outside atmosphere.

  [RB] VAPOR PERMEABLE. The property of having a moisture vapor permeance rating of 5 perms (2.9 × 10 [-10] kg/Pa × s × m [2] ) or greater, where tested in accordance with Procedure A or Procedure B of ASTM E96. A vapor permeable material permits the passage of moisture vapor.

  [RB] VAPOR RETARDER CLASS. A measure of the ability of a material or assembly to limit the amount of moisture that passes through that material or assembly. Vapor retarder class shall be defined using the desiccant method with Procedure A of ASTM E96 as follows:

  Class I: ≤ 0.1 perm rating

  Class II: > 0.1 to ≤ 1.0 perm rating

  Class III: > 1.0 to ≤ 10 perm rating

• CPC § 1007.2 Medium relevance — show source text

  1007.2 Trap Seal Primers. Potable water supply trap seal primer valves shall comply with ASSE 1018. Drainage or electronic design type trap seal primer devices shall comply with ASSE 1044 or IAPMO PS 76.

  1008.0 Building Traps. 1008.1 General. Building traps shall not be installed except where required by the Authority Having Jurisdiction. Each building trap where installed shall be provided with a cleanout and with a relieving vent or fresh-air intake on the inlet side of the trap, which needs not be larger than one-half the diameter of the drain to which it connects. Such relieving vent or fresh-air intake shall be carried above grade and terminate in a screened outlet located outside the building.

  1009.0 Interceptors (Clarifiers) and Separators.

  1009.1 Where Required. Interceptors (clarifiers) (including grease, oil, sand, solid interceptors, etc.) shall be required

  by the Authority Having Jurisdiction where they are necessary for the proper handling of liquid wastes containing grease, flammable wastes, sand, solids, acid or alkaline substances, or other ingredients harmful to the building drainage system, the public or private sewer, or to public or private sewage disposal. A list of acceptable interceptor standards is referenced in Table 1009.1.

  TABLE 1009.1 APPROVED INTERCEPTORS (CLARIFIERS)

  APPLICATION	STANDARD
  Fats, Oil, Grease (FOG)	ASME A112.14.3, ASME A112.14.4, ASME A112.14.6, CSA B481, ANSI/CAN/IAPMO Z1001, PDI G-101, PDI G-102
  Solid Waste	IAPMO IGC 167
  Non-petroleum Oil	ASME A112.14.6, IAPMO PS 80, PDI G-102
  Petroleum Oil	ASTM D6104, IAPMO IGC 183, IAPMO IGC 325

  1009.2 Approval. The size, type, and location of each interceptor (clarifier) or separator shall be approved by the Authority Having Jurisdiction. Except where otherwise specifically permitted, no wastes other than those requiring treatment or separation shall be discharged into an interceptor (clarifier). 1009.3 Design. Interceptors (clarifiers) for sand and similar heavy solids shall be so designed and located as to be readily accessible for cleaning and shall have a water seal of not less than 6 inches (152 mm). 1009.4 Relief Vent. Interceptors (clarifiers) shall be so designed that they will not become air-bound where closed covers are used. Each interceptor (clarifier) shall be properly vented.

• CPC § 911.3 Medium relevance — show source text

  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

  Table 1002.2 Horizontal Lengths of Trap Arms . . . . . . . . . . . . . . . . . . . . . . .195

  1003.2 Slip Joint Fittings . . . . . . . . . . . . .195

  1003.3 Size . . . . . . . . . . . . . . . . . . . . . . . .195

  1004.0 Traps . . . . . . . . . . . . . . . . . . . . . .196

  1004.1 Prohibited . . . . . . . . . . . . . . . . . . .196

  1004.2 Movable Parts . . . . . . . . . . . . . . . .196

  1005.0 Trap Seals . . . . . . . . . . . . . . . . . .196

  1005.1 General . . . . . . . . . . . . . . . . . . . . .196

  1006.0 Floor Drain Traps . . . . . . . . . . . . .196

  1006.1 General . . . . . . . . . . . . . . . . . . . . .196

  1007.0 Trap Seal Protection . . . . . . . . . . .196

  1007.1 General . . . . . . . . . . . . . . . . . . . . .196

  1007.2 Trap Seal Primers . . . . . . . . . . . .196

  1008.0 Building Traps . . . . . . . . . . . . . . . .196

  1008.1 General . . . . . . . . . . . . . . . . . . . . .196

• CPC § 408.4.2 Medium relevance — show source text

  4, 408.4.2(1)| |ASSE 1018-2001 (R2021)|Trap Seal Primer Valves - Potable Water Supplied|Valves|1007.2| |ASSE 1019-2011 (R2016)|Wall Hydrant with Backflow Protection and Freeze Resistance|Backflow Protection|Table 603.2| |ASSE 1020-2020|Pressure Vacuum Breaker Assemblies|Backflow Protection|Table 603.2| |ASSE 1022-2021|Backflow Preventer for Beverage Dispensing Equipment|Backflow Protection|Table 603.2,
  603.5.12| |ASSE 1023-2020|Electrically Heated or Cooled Water Dispensers|Appliances|417.6| |ASSE 1024-2017 (R2021)|Dual Check Backflow Preventers|Backflow Protection|Table 603.2, 603.5.12| |ASSE 1032-2004 (R2021)|Dual Check Valve Type Backflow Preventers for Carbonated
  Beverage Dispensers, Post Mix Type|Backflow Protection|603.5.12| |ASSE 1035-2020|Laboratory Faucet Backflow Preventers|Backflow Protection|Table 603.2,
  603.3.11| |ASSE 1037-2020/ASME
  A112.1037-2020/CSA
  B125.37-2020|Pressurized Flushing Devices for Plumbing Fixtures|Backflow Protection|413.2| |ASSE 1044-2015 (R2020)|Trap Seal Primer - Drainage Types and Electric Design Types|DWV Components|1007.2| |ASSE 1047-2021|Reduced Pressure Detector Backflow Prevention Assemblies|Backflow Protection|Table 603.2| |ASSE 1048-2021|Double Check Detector Backflow Prevention Assemblies|Backflow Protection|Table 603.2| |ASSE 1052-2016|Hose Connection Backflow Preventers|Backflow Protection|Table 603.2| |ASSE 1053-2019|Dual Check Backflow Preventer Wall Hydrants – Freeze
  Resistant Type|Backflow Protection|Table 603.2| |ANSI/CAN/ASSE/IAPMO
  1055-2020|Chemical Dispensers with Integral Backflow Protection|Backflow Protection|Table 603.2,
  603.5.22(1)| |ASSE 1056-2013 (R2021)|Spill Resistant Vacuum Breaker Assemblies|Backflow Protection|Table 603.2| |ASSE 1057-2012|Freeze Resistant Sanitary Yard Hydrants with Backflow Pro-
  tection|Backflow Protection|Table 603.2| |ASSE 1060-2017|Outdoor Enclosures for Fluid Conveying Components with
  Errata dated February 1, 2019|Miscellaneous|603.4.7| |ASSE 1061-2020|Push-Fit Fittings|Fittings|Table 604.1,
  605.1.3.3, 605.2.1.1,
  605.3.2.1, 605.9.3| |ASSE 1062-2017 (R2021)|Temperature Actuated, Flow Reduction (TAFR) Valves for
  Individual Supply Fittings|Valves|408.4.3, 417.

• CPC § 223.0 Medium relevance — show source text

  Trap Arm. Those portions of a fixture drain between a trap and the vent.

  Trap Primer. A device and system of piping that maintains a water seal in a remote trap. Trap Seal. The vertical distance between the crown weir and the top dip of the trap. Crown Weir (Trap Weir). The lowest point in the cross-section of the horizontal waterway at the exit of the trap. Top Dip (of the trap). The highest point in the internal cross-section of the trap at the lowest part of the bend (inverted siphon). By contrast, the bottom dip is the lowest point in the internal cross-section. Treated Gray Water. [BSC-CG & HCD 1] Nonpotable water meeting the definition of “gray water” collected and treated on-site suitable for direct beneficial use.

  223.0 – U –

  UPC. [HCD 1] “UPC” is the latest edition of the Uniform Plumbing Code, published by the International Association of Plumbing and Mechanical Officials. Unsanitary. See Insanitary.

  User Outlet. See Station Outlet.

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  DEFINITIONS

  224.0 – V –

  Vacuum. A pressure less than that exerted by the atmosphere.

  Vacuum Breaker. See Backflow Preventer.

  Vacuum Relief Valve. A device that prevents excessive vacuum in a pressure vessel. Vacuum System-Level 1. A system consisting of central vacuum-producing equipment with pressure and operating controls, shutoff valves, alarm warning systems, gauges, and a network of piping extending to and terminating with suitable station inlets at locations where patient suction could be required. Valve, Balancing. A valve that regulates and controls the return of water to the water heater in a recirculating hot water piping system. Valve, Isolation. A valve that isolates one piece of equipment from another.

  Valve, Pressure-Relief. A pressure-actuated valve held closed by a spring or other means and designed automatically to relieve pressure in excess of its setting.

  Valve, Riser. A valve at the base of a vertical riser that isolates that riser.

  Valve, Service. A valve is serving horizontal piping extending from a riser to a station outlet or inlet. Valve, Source. A single valve at the source that controls a number of units that makes up the source. Valve, Zone. A valve that controls the gas or vacuum to a particular area. Vent. See Plumbing Vent; Dry Vent; Wet Vent. Vent Connector, Gas. That portion of a gas venting system that connects a listed gas appliance beginning at the draft hood or flue collar to a gas vent and is installed entirely within the space or area in which the appliance is located. Vent Offset. An arrangement of two or more fittings and pipe installed for the purpose of locating a vertical section of vent pipe in a different but parallel plane with respect to an adjacent section of vertical vent pipe. [NFPA 54:3.3.101] Vent Pipe. See Plumbing Vent. **Vent Stack.

• CPC § 1101.12.2.2 Medium relevance — show source text

  1101.12.2.2 Secondary Roof Drain. Secondary roof drains shall be provided. The secondary roof drains shall be located not less than 2 inches (51 mm) above the roof surface. The maximum height of the roof drains shall be a height to prevent the depth of ponding water from exceeding that for which the roof was designed as determined by Section 1101.12.1. The secondary roof drains shall connect to a piping system in accordance with Section 1101.12.2.2.1 or Section 1101.12.2.2.2.

  1101.12.2.2.1 Separate Piping System. The secondary roof drainage system shall be a

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  STORM DRAINAGE

  separate system of piping, independent of the primary roof drainage system. The discharge shall be above grade, in a location observable by the building occupants or maintenance personnel. Secondary roof drain systems shall be sized in accordance with Section 1101.12.1

  based on the rainfall rate for which the primary system is sized. 1101.12.2.2.2 Combined System. The secondary roof drains shall connect to the vertical piping of the primary storm drainage conductor downstream of the last horizontal offset located below the roof. The primary storm drainage system shall connect to the building storm water that connects to an underground public storm sewer. The combined secondary and primary roof drain systems shall be sized in accordance with Section 1103.0 based on double the rain fall rate for the local area.

  1101.13 Cleanouts. Cleanouts for building storm drains shall comply with the requirements of Section 719.0 of this code.

  1101.13.1 Rain Leaders and Conductors. Rain leaders and conductors connected to a building storm sewer shall have a cleanout installed at the base of the

  leader or conductor before it connects to the horizontal

  drain.

  1101.14 Rainwater Sumps. Rainwater sumps serving “public use” occupancy buildings shall be provided with dual pumps arranged to function alternately in the case of overload or mechanical failure. Pumps rated 600 V or less shall comply with UL 778 and shall be installed in accordance with the manufacturer’s installation instructions.

  1101.15 Traps on Storm Drains and Leaders. Leaders and storm drains, where connected to a combined sewer, shall be trapped. Floor and area drains connected to a storm drain shall be trapped.

  Exception: Traps shall not be required where roof drains, rain leaders, and other inlets are at locations permitted under Section 906.0, Vent Termination.

  1101.15.1 Where Not Required. No trap shall be required for leaders or conductors that are connected to a sewer carrying storm water exclusively. 1101.15.2 Trap Size. Traps, where installed for individual conductors, shall be the same size as the horizontal drain to which they are connected.

  1101.15.3 Method of Installation of Combined Sewer. Individual storm-water traps shall be installed on the stormwater drain branch serving each storm-water inlet, or a single trap shall be installed in the main storm drain just before its connection with the combined building sewer. Such traps shall be provided with an accessible cleanout on the outlet side of the trap.

• CPC § 2-23 Medium relevance — show source text

  [RB] TERMITE-RESISTANT MATERIAL. Pressure-preservative-treated wood in accordance with the AWPA standards in Section R304.1, naturally durable termite-resistant wood, steel, concrete, masonry or other approved material.

  TESTING AGENCY. An agency approved by the department as qualified and equipped for testing of products, materials, equipment and installations in accordance with nationally recognized standards. For additional information, see Health and Safety Code Section 17920(m).

  [MP] THIRD-PARTY CERTIFICATION AGENCY. An approved agency operating a product or material certification system that incorporates initial product testing, assessment and surveillance of a manufacturer’s quality control system.

  [MP] THIRD-PARTY CERTIFIED. Certification obtained by the manufacturer indicating that the function and performance characteristics of a product or material have been determined by testing and ongoing surveillance by an approved third-party certification agency. Assertion of certification is in the form of identification in accordance with the requirements of the third-party certification agency.

  TODDLER. Any child between 18 months and 36 months of age.

  [RB] TOWNHOUSE. A building that contains three or more attached townhouse units.

  2025 CALIFORNIA RESIDENTIAL CODE 2-23

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  DEFINITIONS

  [RB] TOWNHOUSE UNIT. A single-family dwelling unit in a townhouse that extends from foundation to roof and that has a yard or public way on not less than two sides.

  [MP] TRAP. A fitting, either separate or built into a fixture, that provides a liquid seal to prevent the emission of sewer gases without materially affecting the flow of sewage or wastewater through it.

  [MP] TRAP ARM. That portion of a fixture drain between a trap weir and the vent fitting.

  [MP] TRAP PRIMER. A device or system of piping to maintain a water seal in a trap, typically installed where infrequent use of the trap would result in evaporation of the trap seal, such as floor drains.

  [MP] TRAP SEAL. The trap seal is the maximum vertical depth of liquid that a trap will retain, measured between the crown weir and the top of the dip of the trap.

  [RB] TRIM. Picture molds, chair rails, baseboards, handrails, door and window frames, and similar decorative or protective materials used in fixed applications.

  [RB] TRUSS DESIGN DRAWING. The graphic depiction of an individual truss, that describes the design and physical characteristics of the truss.

  [RB] TUBULAR DAYLIGHTING DEVICE (TDD). A nonoperable fenestration unit primarily designed to transmit daylight from a roof surface to an interior ceiling via a tubular conduit. The basic unit consists of an exterior glazed weathering surface, a light-transmitting tube with a reflective interior surface, and an interior-sealing device such as a translucent ceiling panel. The unit may be factory assembled, or field assembled from a manufactured kit.

  [MP] TYPE L VENT. A listed and labeled vent conforming to UL 641 for venting oil-burning appliances listed for use with Type L vents or with gas appliances listed for use with Type B vents.

• CPC § 101.5 Medium relevance — show source text

  B 101.5 Trap Sizes. Trap sizes are required to be equivalent to the branches they serve (two pipe sizes larger than normal), and tailpieces between fixtures or floor drains and such traps shall be reduced to normal size.

  B 101.6 Layout Drawings. Duplicate layout drawings of each such proposed piping system shall be presented to the Authority Having Jurisdiction and approval obtained before an installation is made. Complicated layouts shall be checked by qualified personnel. B 101.6.1 Example of Sizing. A floor drain normally requires a 2 inch (50 mm) trap and waste. On a combination waste and vent system, both trap and waste shall be increased two pipe sizes (through 2 [1] ⁄ 2 inches and 3 inches) (65 mm and 80 mm), which would make the trap 3 inches (80 mm). Pipe sizes recognized for this purpose are 2 inches, 2 [1] ⁄ 2 inches, 3 inches, 3 [1] ⁄ 2 inches, 4 inches, 4 [1] ⁄ 2 inches, 5 inches, 6 inches, etc. (50 mm, 65 mm, 80 mm, 90 mm, 100 mm, 115 mm, 125 mm, 150 mm, etc.). The tailpiece between the floor drain and its trap shall be 2 inches (50 mm) (or normal size) to ensure that the amount of wastewater entering the trap partially fills the waste branch. A 3 inch (80 mm) floor drain would thus require a 4 inch (100 mm) trap, and a 4 inch (100 mm) floor drain would require a 5 inch (125 mm) trap for the reasons previously stated.

  WHERE IN DOUBT, CHECK WITH YOUR LOCAL Authority Having Jurisdiction.

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  CALIFORNIA PLUMBING CODE – MATRIX ADOPTION TABLE

  APPENDIX C - ALTERNATE PLUMBING SYSTEMS

  (Matrix Adoption Tables are non-regulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)