CPC · California Plumbing Code
Indirect Wastes
Chapter 8 of the CPC sets the rules for indirect-waste connections — when air gaps or air breaks are required, how piping and receptors must be sized and installed, and special provisions for condensate, chemical, and food‑service wastes.
Last reviewed: July 6, 2026
Overview
Chapter 8 of the California Plumbing Code governs indirect waste piping, receptors, and connections — including discharge and treatment of condensate, chemical, industrial, and clear-water wastes — and when an indirect connection (air gap or air break) is required to protect the potable supply and building fixtures. See the chapter introduction and applicability in §801.1 for the scope of these rules .
The code explains the required separation methods (air gap or air break) and the situations that demand them (food equipment, sterile apparatus, potable-water overflows, etc.), with specific dimensional and installation limits (for example, air-gap clearances at §801.2 and food-handling equipment at §801.3.3) . It also covers indirect-waste piping materials, sizing, trap and venting rules at §803.3, and receptor sizing/location requirements at §804.1, plus special provisions for high‑temperature discharges and condensate disposal (see §810.1 and §814.1) file file. Appendix Q (Q901) cross-references Chapter 8 for specialty applications such as plant storage or agricultural water handling .
In this section
Code references
Grounded in the retrieved California Plumbing Code — click a citation to read the verbatim passage:
CPC § 1.11.0. High relevance — show source text
This state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.0.
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CHAPTER 8
INDIRECT WASTES
801.0 General.
801.1 Applicability. This chapter shall govern the materials, design, and installation of indirect waste piping, receptors, and connections; and provisions for discharge and disposal of condensate wastes, chemical wastes, industrial wastes, and clear water wastes.
801.2 Air Gap or Air Break Required. Indirect waste piping shall discharge into the building drainage system through an air gap or air break as set forth in this code. Where a drainage air gap is required by this code, the minimum vertical distance as measured from the lowest point of the indirect waste pipe or the fixture outlet to the flood-level rim of the receptor shall be not less than 1 inch (25.4 mm). 801.3 Food and Beverage Handling Establishments. Establishments engaged in the storage, preparation, selling, serving, processing, or other handling of food and beverage involving the following equipment that requires drainage shall provide indirect waste piping for refrigerators, refrigeration coils, freezers, walk-in coolers, iceboxes, ice-making machines, steam tables, egg boilers, coffee urns and brewers, hot-and-cold drink dispensers, and similar equipment. 801.3.1 Size of Indirect Waste Pipes. Except for refrigeration coils and ice-making machines, the size of the indirect waste pipe shall be not smaller than the drain on the unit, but shall be not smaller than 1 inch (25 mm), and the maximum developed length shall not exceed 15 feet (4572 mm). Indirect waste pipe for ice-making machines shall be not less than the drain on the unit and in no case less than [3] ⁄ 4 of an inch (20 mm). 801.3.2 Walk-In Coolers. For walk-in coolers, floor drains shall be permitted to be connected to a separate drainage line discharging into an outside receptor. The flood-level rim of the receptor shall be not less than 6 inches (152 mm) lower than the lowest floor drain. Such floor drains shall be trapped and individually vented. Cleanouts shall be provided at 90 degree (1.57 rad) turns and shall be accessibly located. Such waste shall discharge through an air gap or air break into a trapped and vented receptor, except that a full-size air gap is required where the indirect waste pipe is under vacuum. 801.3.3 Food-Handling Fixtures. Food-preparation sinks, steam kettles, potato peelers, ice cream dipper wells, and similar equipment shall be indirectly connected to the drainage system by means of an air gap.
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 § 809.0 Medium relevance — show source text
809.0 Drinking Fountains.
809.1 General. Drinking fountains shall be permitted to be installed with indirect wastes through an air break.
810.0 Steam and Hot Water Drainage Condensers and Sumps.
810.1 High-Temperature Discharge. No steam pipe shall be directly connected to plumbing or drainage system, nor shall water having a temperature above 140°F (60°C) be discharged under pressure directly into a drainage system. Pipes from boilers shall discharge by means of indirect waste piping as determined by the Authority Having Jurisdiction or the boiler manufacturer’s recommendations. Such pipes shall be permitted to be indirectly connected by discharging into an open or closed condenser or an intercepting sump of an approved type that will prevent the entrance of steam or such water under pressure into the drainage system. Closed condensers or sumps shall be provided with a vent that shall be taken off the top and extended separately, full size above the roof. Condensers and sumps shall be properly trapped at the outlet with a deep seal trap extending to within 6 inches (152 mm) of the bottom of the tank. The top of the deep seal trap shall have a [3] ⁄ 4 of an inch (19.1 mm) opening located at the highest point of the trap to serve as a siphon breaker. Outlets shall be taken off from the side in such a manner as to allow
a waterline to be maintained that will permanently occupy not
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INDIRECT WASTES
less than one-half the capacity of the condenser or sump. Inlets shall enter above the waterline. Wearing plates or baffles shall be installed in the tank to protect the shell. The sizes of the blowoff line inlet, the water outlets, and the vent shall be as shown in Table 810.1. The contents of condensers
receiving steam or hot water under pressure shall pass through an open sump before entering the drainage system.
TABLE 810.1
PIPE CONNECTIONS IN BLOWOFF
CONDENSERS AND SUMPS (inches)
BOILER BLOWOFF WATER OUTLET VENT 3⁄4* 3⁄4* 2
11 21⁄2
11⁄411⁄4 3
11⁄211⁄2 4
22 5
21⁄221⁄2 6 For SI units: 1 inch = 25 mm
- To be used only with boilers of 100 square feet (9.29 m [2] ) of heating surface or less.
CPC § 811.3 Medium relevance — show source text
CPVC pipe and fittings shall comply with ASTM F2618. PP pipe and fittings shall comply with ASTM F1412 or CSA B181.3. PVDF pipe and fittings shall comply with ASTM F1673 or CSA B181.3. Chemical-resistant glass pipe and fittings shall comply with ASTM C1053. High-silicon iron pipe and fittings shall comply with ASTM A861.
811.3 Joining Materials. Joining materials shall be of approved type and quality.
811.4 Access. Where practicable, the piping shall be readily accessible and installed with the maximum of clearance from other services.
811.5 Permanent Record. The owner shall make and keep a permanent record of the location of piping and venting carrying chemical waste.
811.6 Chemical Vent. No chemical vent shall intersect
vents for other services.
811.7 Discharge. Chemical wastes shall be discharged in a manner approved by the Authority Having Jurisdiction.
811.8 Diluted Chemicals. The provisions of this section about materials and methods of construction shall not apply to installations such as photographic or x-ray darkrooms or research or control laboratories where minor amounts of ade quately diluted chemicals are discharged.
812.0 Clear Water Wastes.
812.1 General. Water lifts, expansion tanks, cooling jackets, sprinkler systems, drip or overflow pans, or similar devices that discharge clear wastewater into the building drainage system shall discharge through an indirect waste.
813.0 Swimming Pools.
813.1 General. Pipes carrying wastewater from swimming or wading pools, including pool drainage and backwash from filters, shall be installed as an indirect waste. Where a pump is used to discharge pool waste water to the drainage system, the pump discharge shall be installed as an indirect waste.
814.0 Condensate Waste and Control.
814.1 Condensate Disposal. Condensate from air washers, air-cooling coils, condensing appliances, and the over
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INDIRECT WASTES
flow from evaporative coolers and similar water-supplied equipment or similar air-conditioning equipment shall be collected and discharged to an approved plumbing fixture or disposal area. Where discharged into the drainage system, equipment shall drain using an indirect waste pipe. The waste pipe shall have a slope of not less than [1] ⁄ 8 inch per foot (10.4 mm/m) or 1 percent slope and shall be of an approved corrosion-resistant material not smaller than the outlet size in
accordance with Section 814.3 or Section 814.4 for air-cooling coils or condensing appliances, respectively. Condensate or wastewater shall not drain over a public way.
814.1.1 Condensate Pumps. Where approved by the Authority Having Jurisdiction, condensate pumps shall be installed in accordance with the manufacturer’s instal lation instructions. Pump discharge shall rise vertically to a point where it is possible to connect to a gravity condensate drain and discharged to an approved disposal point. Each condensing unit shall be provided with a separate sump and interlocked with the equipment to prevent the equipment from operating during a failure. Separate pumps shall be permitted to connect to a single gravity indirect waste where equipped with check valves and approved by the Authority Having Jurisdiction.
CPC § 2025 Medium 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 § 801.4 Medium relevance — show source text
The piping from the equipment to the receptor shall be not less than the drain on the unit and in no case less than [1] ⁄ 2 of an inch (15 mm).
801.4 Bar and Fountain Sink Traps. Where the sink in a bar, soda fountain, or counter is so located that the trap serving the sink cannot be vented, the sink drain shall discharge through an air gap or air break (see Section 801.3.3) into an approved receptor that is vented. The developed length from the fixture outlet to the receptor shall not exceed 5 feet (1524 mm). 801.5 Connections from Water Distribution System. Indirect waste connections shall be provided for drains, overflows, or relief pipes from potable water pressure tanks, water heaters, boilers, and similar equipment that is connected to the potable water distribution system. Such indirect waste connections shall be made using a water-distribution air gap constructed in accordance with Table 603.3.1.
801.6 Sterilizers. Lines, devices, or apparatus such as stills, sterilizers, and similar equipment requiring waste connections and used for sterile materials shall be indirectly connected using an air gap. Each such indirect waste pipe shall be separately piped to the receptor and shall not exceed 15 feet (4572 mm). Such receptors shall be located in the same room. 801.7 Drip or Drainage Outlets. Appliances, devices, or apparatus not regularly classified as plumbing fixtures, but which have a drip or drainage outlets, shall be permitted to be drained by indirect waste pipes discharging into an open receptor through either an air gap or air break (see Section 801.3.1).
802.0 Approvals. 802.1 General. No plumbing fixtures served by indirect waste pipes or receiving discharge therefrom shall be installed until first approved by the Authority Having Jurisdiction.
803.0 Indirect Waste Piping.
803.1 Materials. Pipe, tube, and fittings conveying indirect waste shall be of such materials and design as to perform their intended function to the satisfaction of the Authority Having Jurisdiction.
803.2 Copper and Copper Alloys. Joints and connections in copper and copper alloy pipe and tube shall be installed in accordance with Section 705.3.
803.3 Pipe Size and Length. Except as hereinafter provided, the size of indirect waste piping shall be in accordance with other sections of this code applicable to drainage and vent piping. No vent from indirect waste piping shall combine with a sewer-connected vent. Vents from indirect waste piping shall extend separately to the outside air. Indirect waste pipes exceeding 5 feet (1524 mm), but less than 15 feet (4572 mm) in length shall be directly trapped, but such traps need not be vented.
Indirect waste pipes less than 15 feet (4572 mm) in length shall be not less than the diameter of the drain outlet or
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INDIRECT WASTES
tailpiece of the fixture, appliance, or equipment served, and in no case less than [1] ⁄ 2 of an inch (15 mm). Angles and changes of direction in such indirect waste pipes shall be provided with cleanouts to permit flushing and cleaning.
804.0 Indirect Waste Receptors.
**804.1 Standpipe Receptors.
CPC § 801.3.1 Medium relevance — show source text
801.3.1 Size of Indirect Waste Pipes. Except for refrigeration coils and ice-making machines, the size of the indirect waste pipe shall be not smaller than the drain on the unit, but shall be not smaller than 1 inch (25 mm), and the maximum developed length shall not exceed 15 feet (4572 mm). Indirect waste pipe for ice-making machines shall be not less than the drain on the unit and in no case less than [3] ⁄ 4 of an inch (20 mm). 801.3.2 Walk-In Coolers. For walk-in coolers, floor drains shall be permitted to be connected to a separate drainage line discharging into an outside receptor. The flood-level rim of the receptor shall be not less than 6 inches (152 mm) lower than the lowest floor drain. Such floor drains shall be trapped and individually vented. Cleanouts shall be provided at 90 degree (1.57 rad) turns and shall be accessibly located. Such waste shall discharge through an air gap or air break into a trapped and vented receptor, except that a full-size air gap is required where the indirect waste pipe is under vacuum. 801.3.3 Food-Handling Fixtures. Food-preparation sinks, steam kettles, potato peelers, ice cream dipper wells, and similar equipment shall be indirectly connected to the drainage system by means of an air gap. Bins, sinks, and other equipment having drainage connections and used for the storage of unpackaged ice used for human ingestion, or used in direct contact with ready-to-eat food, shall be indirectly connected to the drainage system by means of an air gap. Each indirect waste pipe from foodhandling fixtures or equipment shall be separately piped to the indirect waste receptor and shall not combine with other indirect waste pipes. The piping from the equipment to the receptor shall be not less than the drain on the unit and in no case less than [1] ⁄ 2 of an inch (15 mm).
801.4 Bar and Fountain Sink Traps. Where the sink in a bar, soda fountain, or counter is so located that the trap serving the sink cannot be vented, the sink drain shall discharge through an air gap or air break (see Section 801.3.3) into an approved receptor that is vented. The developed length from the fixture outlet to the receptor shall not exceed 5 feet (1524 mm). 801.5 Connections from Water Distribution System. Indirect waste connections shall be provided for drains, overflows, or relief pipes from potable water pressure tanks, water heaters, boilers, and similar equipment that is connected to the potable water distribution system. Such indirect waste connections shall be made using a water-distribution air gap constructed in accordance with Table 603.3.1.
801.6 Sterilizers. Lines, devices, or apparatus such as stills, sterilizers, and similar equipment requiring waste connections and used for sterile materials shall be indirectly connected using an air gap. Each such indirect waste pipe shall be separately piped to the receptor and shall not exceed 15 feet (4572 mm). Such receptors shall be located in the same room. 801.7 Drip or Drainage Outlets. Appliances, devices, or apparatus not regularly classified as plumbing fixtures, but which have a drip or drainage outlets, shall be permitted to be drained by indirect waste pipes discharging into an open receptor through either an air gap or air break (see Section 801.3.1).
CPC § 3141B.1 Medium relevance — show source text
3141B.1 General requirements. Material cleaned from filters and backwash water from any recirculation system shall be disposed in a manner that is acceptable to the local wastewater agency and will not create a nuisance. Backwash water shall not be returned to a pool. Pipes carrying wastewater from pools including pool drainage and backwash from filters shall be installed as an indirect waste in accordance with the requirements of Chapter 8 of the California Plumbing Code. Where a pump is used to discharge waste pool water to the drainage system, the pump discharge shall be installed as an indirect waste.
3141B.2 Diatomaceous earth filters. The backwash from a diatomaceous earth filter shall discharge into a separation tank that has been installed to collect the waste diatomaceous earth mixture. The wastewater from the separation tank shall discharge into a sanitary sewer or other disposal system acceptable to the local wastewater agency.
3141B.3 Piping. Sumps and drain piping shall have sufficient capacity to receive recirculation system backwash without overflow of the sump receiver. The sump shall not permit sewage to enter the surge basin or the pool in the event of a sewage backup
3141B.4 Visual indicator. Where direct observation of the backwash discharge is not visible to the operator during backwash opera- tions, a sight glass shall be installed on the wastewater discharge line.
3141B.5 Prohibited connection. There shall be no direct connection between the pool, its recirculation system or overflow drain to any sanitary sewer, storm drain or drainage system.
SECTION 3142B—RESERVED
SECTION 3143B—RESERVED
SECTION 3144B—RESERVED
SECTION 3145B—RESERVED
SECTION 3146B—RESERVED
SECTION 3147B—RESERVED
SECTION 3148B—RESERVED
SECTION 3149B—RESERVED
SECTION 3150B—RESERVED
SECTION 3151B—RESERVED
SECTION 3152B—RESERVED
SECTION 3153B—RESERVED
SECTION 3154B—RESERVED
SECTION 3155B—RESERVED
SECTION 3156B—RESERVED
31B-20 2025 CALIFORNIA BUILDING CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
PUBLIC POOLS
SECTION 3157B—RESERVED
SECTION 3158B—RESERVED
SECTION 3159B—RESERVED
Division II – PUBLIC SWIMMING POOLS
Note: These building standards are in statute but have not been adopted through the regulatory process. Enforcement of these stan- dards set forth in this section does not depend upon adoption of regulations; therefore, enforcement agencies shall enforce the standards pursuant to the timeline set forth in this section prior to adoption of related regulations.
SECTION 3160B—GROUND FAULT CIRCUIT INTERRUPTERS
CPC § 901.0 Medium relevance — show source text
APPENDIX Q
Q 901.0 Sanitary Drainage and Indirect Wastes. Q 901.1 General. Sanitary drainage shall be in accordance with Chapter 7. Indirect wastes shall be in accordance with Chapter 8. The drainage system shall be compatible with the discharge liquid waste.
Q 901.2 Hazardous Materials. Hazardous materials shall not be discharged into the sanitary sewer, storm drain, or on the ground. Q 901.3 Agricultural Water Waste. Agricultural water shall be discharged in accordance with the local, state, and federal regulations as approved by the Authority Having Jurisdiction. Where agricultural water discharges to the outdoors, and is not connected to the sanitary sewer, the piping shall be installed as to restrict rodents or vermin from entering the building. Q 901.4 Floor Drains, Floor Sinks, and Receptors. Wastewater shall discharge into an approved receptor. Receptors shall be compatible with the wastewater and installed in accordance with this code.
Q 901.4.1 Plant Storage Areas. Where drains are provided in spaces where plants are stored, such drains shall be installed with indirect waste piping. Each indirect waste pipe from plant storage areas shall be separately piped to the indirect waste receptor and shall not combine with other indirect waste pipes.
Q 1001.0 Facilities.
Q 1001.1 Toilet Facilities. Toilet facilities shall be provided in accordance with the occupancy type.
Q 1001.2 Location. Toilet facilities shall be located in such a manner to prevent contamination of plants during harvesting, holding, manufacturing/processing, and packing.
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CALIFORNIA PLUMBING CODE – MATRIX ADOPTION TABLE
APPENDIX R - TINY HOUSES
(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.)
CPC § 901.4.1 Medium relevance — show source text
Q 901.4.1 Plant Storage Areas. Where drains are provided in spaces where plants are stored, such drains shall be installed with indirect waste piping. Each indirect waste pipe from plant storage areas shall be separately piped to the indirect waste receptor and shall not combine with other indirect waste pipes.
Q 1001.0 Facilities.
Q 1001.1 Toilet Facilities. Toilet facilities shall be provided in accordance with the occupancy type.
Q 1001.2 Location. Toilet facilities shall be located in such a manner to prevent contamination of plants during harvesting, holding, manufacturing/processing, and packing.
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CALIFORNIA PLUMBING CODE – MATRIX ADOPTION TABLE
APPENDIX R - TINY HOUSES
(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.)
Adopting Agency BSC BSC-
CGSFM HCD Col6 Col7 DSA Col9 Col10 OSHPD Col12 Col13 Col14 Col15 Col16 Col17 BSCC DPH AGR DWR CEC CA SL SLC Adopting Agency BSC BSC-
CGSFM 1 2 1-AC AC ** SS** SS/CC 1 1R 2 3 4 5 6 6 6 6 6 6 6 6 6 Adopt Entire Chapter X Adopt Entire Chapter as
amended (amended
sections listed below)Adopt only those sections
that are listed belowChapter/Section This state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.0.
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APPENDIX R
TINY HOUSES
The provisions contained in this appendix are not mandatory unless specifically adopted by a state agency, or referenced in the adopting ordinance.
R 101.0 Tiny Houses.
CPC § 601.0 Medium relevance — show source text
Q 601.0 Water Supply. Q 601.1 General. Indoor horticulture water distribution systems shall be supplied with potable water in accordance with Chapter 6. Q 601.2 Materials. Pipe, tube, and fitting materials in contact with potable water, drinking water, or both shall be in accordance with Section 604.0.
Q 601.3 Protection. Potable water piping used for irrigation purposes shall be equipped with an approved backflow prevention device or assembly in accordance with Table 603.2.
Q 601.4 Alternate Water Supply. Where permitted, agricultural water may be used or alternate water sources in accordance with Appendix K.
Q 701.0 Storage Tanks. Q 701.1 Construction. Where storage tanks are used, they shall be approved by the Authority Having Jurisdiction. Potable water storage tanks shall comply with Section 607.0. Rainwater catchment storage tanks shall comply with Appendix K or in accordance with the Authority Having Jurisdiction.
Q 801.0 Fertigation and Irrigation Equipment. Q 801.1 Installation. Nutrient tanks and irrigation equipment shall be installed in accordance with the manufacturer’s instructions. When connected to the potable water supply, tanks and irrigation equipment shall be located downstream of water storage tank and be protected by an approved backflow device or method in accordance with Table 603.2
Q 801.2 Materials and Construction. The piping, components, and devices shall be compatible with the additives or nutrients used. Above grade storage tanks shall be of an opaque material, approved for aboveground use in direct sunlight, or shall be shielded from direct sunlight.
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APPENDIX Q
Q 901.0 Sanitary Drainage and Indirect Wastes. Q 901.1 General. Sanitary drainage shall be in accordance with Chapter 7. Indirect wastes shall be in accordance with Chapter 8. The drainage system shall be compatible with the discharge liquid waste.
Q 901.2 Hazardous Materials. Hazardous materials shall not be discharged into the sanitary sewer, storm drain, or on the ground. Q 901.3 Agricultural Water Waste. Agricultural water shall be discharged in accordance with the local, state, and federal regulations as approved by the Authority Having Jurisdiction. Where agricultural water discharges to the outdoors, and is not connected to the sanitary sewer, the piping shall be installed as to restrict rodents or vermin from entering the building. Q 901.4 Floor Drains, Floor Sinks, and Receptors. Wastewater shall discharge into an approved receptor. Receptors shall be compatible with the wastewater and installed in accordance with this code.
Q 901.4.1 Plant Storage Areas. Where drains are provided in spaces where plants are stored, such drains shall be installed with indirect waste piping. Each indirect waste pipe from plant storage areas shall be separately piped to the indirect waste receptor and shall not combine with other indirect waste pipes.
Q 1001.0 Facilities.
Q 1001.1 Toilet Facilities. Toilet facilities shall be provided in accordance with the occupancy type.
Q 1001.2 Location. Toilet facilities shall be located in such a manner to prevent contamination of plants during harvesting, holding, manufacturing/processing, and packing.
CPC § 418.4 Medium relevance — show source text
(3) Laundry rooms in commercial buildings and common laundry facilities in multi-family dwelling buildings. (4) Boiler rooms. 418.4 Food Storage Areas. Where drains are provided in storerooms, walk-in freezers, walk-in coolers, refrigerated equipment, or other locations where food is stored, such drains shall have indirect waste piping. Separate waste pipes shall be run from each food storage area, each with an indirect connection to the building sanitary drainage system. Traps shall be provided in accordance with Section 801.3.2 of this code and shall be vented.
Indirect drains shall be permitted to be located in freezers or other spaces where freezing temperatures are maintained, provided that traps, where supplied, shall be located where the seal will not freeze. Otherwise, the floor of the freezer shall be sloped to a floor drain located outside of the storage compartment. 418.5 Floor Slope. Floors shall be sloped to floor drains.
419.0 Food Waste Disposers. 419.1 Application. Food waste disposal units shall comply with UL 430. Residential food waste disposers shall also comply with ASSE 1008. 419.2 Drainage Connection. Approved wye or other directional-type branch fittings shall be installed in continuous wastes connecting or receiving the discharge from a food waste disposer. No dishwasher drain shall be connected to a sink tailpiece, continuous waste, or trap on the discharge side of a food waste disposer. 419.3 Water Supply. A cold water supply shall be provided for food waste disposers. Such connection to the water supply shall be protected by an air gap or backflow prevention device in accordance with Section 603.2.
420.0 Sinks.
420.1 Application. Sinks shall comply with ASME A112.19.1/CSA B45.2, ASME A112.19.2/CSA B45.1, ASME A112.19.3/CSA B45.4, CSA B45.5/IAPMO Z124, CSA B45.8/IAPMO Z403, or CSA B45.12/IAPMO Z402. Moveable sink systems shall comply with ASME A112.19.12. Sink assemblies with automatic soap dispensers, faucets, or hand dryers shall comply with IAPMO IGC 127. 420.2 Water Consumption. Sink faucets shall have a maximum flow rate of not more than 2.2 gpm at 60 psi (8.3 L/m at 414 kPa).
Exceptions: (1) Clinical sinks (2) Laundry sinks (3) Service sinks
420.2.1 Kitchen Faucets. [BSC-CG & DSA-SS] Kitchen faucets shall have a maximum flow rate of not more than 1.8 gallons (6.81 L) per minute at 60 psi (414 kPa). Kitchen faucets may temporarily increase the flow above the maximum rate, but not to exceed 2.2 gallons (8.3 L) per minute at 60 psi (414 kPa), and must default to a maximum flow rate of 1.8 gallons (6.81 L) per minute at 60 psi (414 kPa) in compliance with Chapter 5, Division 5.3 of the California Green Building Stan- dards Code (CALGreen). _**420.2.2 Kitchen Faucets.
Frequently asked questions
When is an air gap required instead of a direct connection?
An air gap is required where a discharge could pose a health hazard or create a cross‑connection with potable water; the CPC explains that an air gap or air break must be used for indirect waste discharges and gives minimum vertical clearances for air gaps at §801.2 .
What are the common minimum sizes and length limits for indirect-waste piping?
Unless otherwise specified for particular equipment, indirect-waste piping must be at least the size of the unit’s drain (and in many cases not less than 1/2" or 1" depending on the appliance); food‑service equipment typically requires not smaller than 1" (with ice‑making machines allowed at 3/4"), and developed lengths are limited (commonly 15 ft maximum for many indirect connections) — see §§801.3.1 and 803.3 for details file.
May an indirect waste receptor be located in a toilet room or storeroom?
No. Indirect waste receptors must be accessible and sized to prevent splashing or flooding and generally may not be installed in toilet rooms, closets, cupboards, or storerooms; limited exceptions (for example clothes-washer standpipes) are called out in §804.1 .
More in California Plumbing Code
- Administration
- Definitions
- General Regulations
- Plumbing Fixtures and Fixture Fittings
- Water Heaters
- Water Supply and Distribution
- Sanitary Drainage (Drain, Waste, and Vent)
- Indirect Wastes
- Vents
- Traps and Interceptors
- Storm Drainage
- Fuel Gas Piping
- Health Care Facilities — Medical Gas and Medical Vacuum Systems
- Alternate Water Sources and Nonpotable Rainwater Catchment Systems
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