CPC · California Plumbing Code
What materials and minimum sizes are allowed for indirect waste piping?
Indirect waste piping must be made of materials approved by the local authority and sized at least as large as the equipment drain with Chapter 8 minimums: generally **½"** (non‑food), **1"** for most food‑service equipment, and **¾"** for ice‑makers; certain condensate/refrigeration drains use table‑based sizes. Traps, air gaps/air breaks, separate vents, and cleanouts are required in specific length and equipment conditions — see **§ 803.1** and **§ 801.3.1** for the controlling rules.
Last reviewed: July 6, 2026
What the code requires — 2–4 sentences
The California Plumbing Code requires that pipe, tube, and fittings conveying indirect waste be made of materials and designed to perform their intended function to the satisfaction of the Authority Having Jurisdiction — see § 803.1. For sizing, the Code generally requires indirect waste piping be at least the diameter of the fixture tailpiece or drain, with specific minimums in Chapter 8 (notably § 803.3 and § 801.3.1) for food‑service equipment and certain appliances. Where equipment-specific rules exist (food/beverage equipment, ice makers, refrigeration coils, condensate), those rules control over the general provisions.
Indirect waste piping must be made of approved materials and be at least as large as the unit’s drain — with explicit minimums: ½", ¾", or 1" depending on the equipment and Chapter 8 rules.
Requirements in detail
Materials (what is allowed)
- The Code’s basic rule: materials must be suitable for the intended function and approved by the Authority Having Jurisdiction (AHJ) — § 803.1. That is the controlling materials requirement for indirect waste piping.
- Special material rules: for certain wastes (condensate, chemical/industrial, clear water, etc.) Chapter 8 and Chapter 7 give more specific material requirements (for example, condensate piping 1¼" and larger must be constructed of materials specified in Chapter 7). See § 814.3 and related text.
- Copper/copper‑alloy tubing joints must be installed per the copper provisions (see § 803.2 referencing Section 705.3).
Minimum sizes, lengths, trapping and venting rules
Below is a decision table summarizing the common minimums and limits you will use when choosing pipe size and installation method.
| Equipment / Condition | Minimum pipe size (inches) | Max developed length | Trapping / venting / notes | Code Reference |
|---|---|---|---|---|
| General indirect wastes (non‑food equipment) | At least the diameter of the drain/tailpiece; in no case less than 1/2" (15 mm) | < 15 ft (4572 mm) unless otherwise stated | Angles/changes require cleanouts; vents from indirect waste piping must extend separately to outside air (cannot combine with sewer-connected vent) | § 803.3 |
| Food & beverage equipment (refrigerators, steam tables, coffee brewers, etc.; except refrigeration coils & ice machines) | At least the drain on the unit; in no case less than 1" (25 mm) | 15 ft (4572 mm) max developed length | Each indirect waste from food‑handling fixtures must be separately piped to receptor in many cases; air gap/air break required where specified | § 801.3.1 |
| Ice‑making machines | At least the drain on the unit; in no case less than 3/4" (20 mm) | 15 ft max where referenced | Follow food‑service indirect waste rules for receptors/air gaps | § 801.3.1 |
| Refrigeration coils (condensate from coils) | See equipment capacity table; small units may use 3/4", 1", 1¼", etc. (Table 814.3) | Depends on unit capacity — see Table 814.3 | Condensate piping 1¼" and larger must be of materials specified in Chapter 7; slope ≥ 1/8" per foot | § 814.3 and Table 814.3 |
| Indirect waste pipes > 5 ft (1524 mm) but < 15 ft (4572 mm) | See above minimums | See trapping rule below | Indirect waste piping exceeding 5 ft but less than 15 ft must be directly trapped; such traps need not be vented. Cleanouts required at angles/changes to permit flushing/cleaning. | § 803.3 |
Notes on the table:
- The general minimum ½" comes from § 803.3, but where Chapter 8 (food service) sets higher minimums, those specific minimums control (see § 801.3.1).
- Condensate sizing for air‑conditioning coils is given in Table 814.3 (min diameters by refrigeration tons) and materials guidance is in § 814.3.
Installation details you must not forget
- Air gap / air break requirement: Indirect wastes must discharge into the drainage system through an air gap or air break where required; the minimum vertical distance for a drainage air gap is 1 inch (25.4 mm) from the lowest point of the indirect waste pipe to the receptor flood‑rim when an air gap is required — § 801.2.
- Cleanouts: Angles and changes of direction in indirect waste pipes shall be provided with cleanouts to permit flushing and cleaning — § 803.3.
- Separate vents: Vents from indirect waste piping shall not combine with a sewer‑connected vent and shall extend separately to outside air — § 803.3.
- Trapping: Indirect waste runs between > 5 ft and < 15 ft must be directly trapped; such traps need not be vented — § 803.3.
Exceptions & special cases
- Refrigeration coils and condensate: Refrigeration coils are handled separately from the food‑service pipe minimum in § 801.3.1; condensate sizing and materials are addressed in § 814.3 and Table 814.3 (equipment capacity-based minimums). Do not apply the 1" food‑service minimum to refrigeration coils without checking § 814.3 and the AHJ.
- Ice‑making machines: Specifically allowed a minimum of 3/4" regardless of unit drain size — § 801.3.1.
- Short runs: The general minimum of ½" applies to many short indirect waste runs (<15 ft) per § 803.3, but where a specialized section sets a larger minimum, the specialty section controls.
- Pressure discharge devices (pumps, pressure‑waste devices): Indirect connections are required for drains or reliefs from pressure systems; approved exceptions (e.g., some sump pumps) may apply with AHJ approval — see § 805.1.
Common mistakes
- Installing an indirect waste smaller than the unit’s drain or smaller than the code minimum (½", ¾", 1") for the equipment — check § 803.3 and § 801.3.1.
- Applying the food‑service 1" minimum to refrigeration coils or to condensate lines instead of checking § 814.3 and Table 814.3. Always confirm whether the equipment is covered by § 801.3.1 or § 814.3.
- Failing to provide a required air gap / air break into the receptor (see § 801.2), or using a direct connection where an air gap is specified.
- Combining vents from indirect waste piping with sewer‑connected vents — not allowed per § 803.3.
- Omitting cleanouts at changes of direction or using materials not acceptable to the AHJ for a given waste (chemical/industrial wastes need special material and venting provisions — see Chapter 8 chemical wastes).
Worked example — ice‑making machine in a café
Scenario: A café installs an ice‑making machine that has a factory drain outlet of 3/8". The indirect waste run from the ice machine to the mop sink receptor will be 12 ft (3658 mm) developed length.
Apply the Code:
- Equipment type: ice‑making machine → governed by § 801.3.1 for ice machines.
- Minimum size: § 801.3.1 requires indirect waste for ice‑making machines be not less than the drain on the unit and in no case less than 3/4". So select 3/4".
- Length and trapping: The developed length is 12 ft, which is between > 5 ft and < 15 ft. Under § 803.3, an indirect waste pipe exceeding 5 ft but less than 15 ft must be directly trapped (trap need not be vented). Provide a trap near the machine.
- Air gap/air break and receptor: The ice‑machine indirect waste must discharge through an air gap or air break into an approved receptor per § 801.2 and Chapter 8 receptor rules. Ensure the receptor’s flood‑rim and air‑gap clearance meet § 801.2 (minimum 1" vertical clearance when a drainage air gap is required).
- Cleanouts: Provide a cleanout where there are changes of direction per § 803.3.
Outcome: Use 3/4" indirect waste piping, directly trap the run, provide required air gap into the receptor, and add cleanouts at turns. Cite and document these steps on the plan for AHJ review.
Related provisions
- § 803.1 — Materials for indirect waste piping (general requirement).
- § 803.3 — Pipe sizing, lengths, traps, vents, cleanouts for indirect wastes.
- § 801.2 — Air gap / air break requirements for indirect waste discharge.
- § 801.3.1 — Size rules for food & beverage establishment indirect waste piping (min 1" or 3/4" for ice machines).
- § 814.3 and Table 814.3 — Condensate waste pipe material and minimum sizes by equipment capacity.
- § 803.2 — Copper and copper‑alloy joints for indirect waste piping (installation reference).
Code references
Grounded in the retrieved California Plumbing Code — click a citation to read the verbatim passage:
CPC § 803.0 High relevance — show source text
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. Plumbing fixtures or other receptors receiving the discharge of indirect waste pipes shall be approved for the use proposed and shall be of such shape and capacity as to prevent splashing or flooding and shall be located where they are readily accessible for inspection and cleaning. No standpipe receptor for a clothes washer shall extend more than 30 inches (762 mm), or not less than 18 inches (457 mm) above its trap weir. No trap for a clothes washer standpipe receptor shall be installed below the floor, but shall be roughed in not less than 6 inches (152 mm) and not more than 18 inches (457 mm) above the floor. No indirect waste receptor shall be installed in a toilet room, closet, cupboard, or storeroom, or in a portion of a building not in general use by the occupants thereof; except standpipes for clothes washers shall be permitted to be installed in toilet and bathroom areas where the clothes washer is installed in the
same room.
805.0 Pressure Drainage Connections. 805.1 General. Indirect waste connections shall be provided for drains, overflows, or relief vents from the water supply system, and no piping or equipment carrying wastes or producing wastes or other discharges under pressure shall be directly connected to a part of the drainage system.
The preceding shall not apply to an approved sump pump or to an approved pressure-wasting plumbing fixture or device where the Authority Having Jurisdiction has been satisfied that the drainage system is adequately sized to accommodate the anticipated discharge thereof.
806.0 Sterile Equipment.
806.1 General. Appliances, devices, or apparatus such as stills, sterilizers, and similar equipment requiring water and waste and used for sterile materials shall be drained through an air gap.
807.0 Appliances.
CPC § 801.4 High 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 § 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 § 310.2.1 High relevance — show source text
310.2.1 Protection of Appurtenances. Where insulation or appurtenances are installed where damage is capable of resulting from a condensate drain pan overfill, such installations shall occur above the rim of the drain
pan with supports. Where the supports are in contact with the condensate waste, the supports shall be of approved corrosion-resistant material.
310.3 Condensate Waste Pipe Material and Sizing. Condensate waste pipes from air-cooling coils shall be sized in accordance with the equipment capacity as specified in Table 310.3. The material of the piping shall comply with the pressure and temperature rating of the appliance or equipment, and shall be approved for use with the liquid being discharged.
TABLE 310.3
MINIMUM CONDENSATE PIPE SIZE
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GENERAL REGULATIONS
Condensate drain sizing for other slopes or other conditions shall be approved by the Authority Having Jurisdiction.
Air-conditioning waste pipes, 1¼ of an inch (32 mm) and larger in size, shall be constructed of materials specified in the plumbing code. Condensate waste piping less than 1¼ of an inch (32 mm) in size shall be permitted to be PVC, CPVC, PE, PP, copper, or other rigid materials approved by the Authority Having Jurisdiction.
310.3.1 Cleanouts. Condensate drain lines shall be configured or provided with a cleanout to permit the clearing of blockages and for maintenance without requiring the drain line to be cut.
310.4 Appliance Condensate Drains. Condensate drain lines from individual condensing appliances shall be sized as required by the manufacturer’s instructions. Condensate drain lines serving more than one appliance connecting to a common indirect waste pipe shall have the connections to the indirect waste pipe protected by a sanitary waste valve complying with ASME A112.18.8, condensate trap complying with IAPMO IGC 196, or trap with a trap primer.
310.5 Point of Discharge. Air-conditioning condensate waste pipes shall connect indirectly to the drainage system through an air gap or air break to trapped and vented receptors, dry wells, mop sinks, leach pits, or the tailpiece of plumbing fixtures. An individual condensate drain shall be trapped in accordance with the appliance manufacturer’s instructions or in accordance with Section 310.4.
310.6 Condensate Waste from Air-Conditioning Coils. Where the condensate waste from air-conditioning coils discharges by direct connection to a lavatory tailpiece or to an approved accessible inlet on a bathtub overflow, the connection shall be located in the area controlled by the same person controlling the air-conditioned space. 310.7 Female Plastic Connections. Female plastic screwed fittings shall be used with plastic male fittings and plastic male threads. Female plastic threaded connections shall not be allowed to be used when threaded onto a male
metallic connection.
311.0 Heating or Cooling Air System. 311.1 Source. A heating or cooling air system shall be provided with return air, outside air, or both. A heating or cooling air system regulated by this code and designed to replace required ventilation shall be arranged to discharge into a conditioned space not less than the amount of outside air specified in Chapter 4.
CPC § 801.3.1 High 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 § 1.6 High relevance — show source text
PLUMBING APPLIANCES, APPURTENANCES, OR FIXTURES MINIMUM SIZE TRAP
AND TRAP ARM7
(inches)PRIVATE PUBLIC ASSEMBLY8 Water Closet, greater than 1.6 GPF Gravity Tank6 3 4.0 6.0 8.0 Water Closet, greater than 1.6 GPF Flushometer Valve6 3 4.0 6.0 8.0 For SI units: 1 inch = 25 mm
Notes: 1 Indirect waste receptors shall be sized based on the total drainage capacity of the fixtures that drain thereinto, in accordance with Table 702.2. 2 Provide a 2 inch (50 mm) minimum drain. 3 For refrigerators, coffee urns, water stations, and similar low demands. 4 For commercial sinks, dishwashers, and similar moderate or heavy demands. 5 Buildings having a clothes-washing area with clothes washers in a battery of three or more clothes washers shall be rated at 6 fixture units each for purposes of sizing common horizontal and vertical drainage piping. 6 Water closets shall be computed as 6 fixture units where determining septic tank sizes based on Appendix H of this code. 7 Trap sizes shall not be increased to the point where the fixture discharge is capable of being inadequate to maintain their self-scouring properties. 8 Assembly [Public Use (see Table 422.1)]. 9 For a bathtub to shower retrofit, a 1 1 / 2 inch (40 mm) trap and trap arm shall be permitted with a maximum shower size of 36 inches (914 mm) in width and 60 inches (1524 mm) in length. See Section 408.6 and Section 408.7. 10 For drainage fixture unit values related to lots within mobilehome parks in all parts of the State of California, see California Code of Regulations, Title 25, Division 1, Chapter 2, Article 5, Section 1268. For drainage fixture unit values related to lots within special occupancy parks in all parts of the State of Cal- ifornia, see California Code of Regulations, Title 25, Division 1, Chapter 2.2, Article 5, Section 2268.
required, and the unit equivalent of fixtures and devices not shown in Table 702.1 shall be based on the size of trap or trap
arm.
Maximum drainage fixture units for a fixture trap and trap arm loadings for sizes up to 4 inches (100 mm) shall be in accordance with Table 702.1(1).
TABLE 702.1(1) MAXIMUM DRAINAGE FIXTURE UNITS FOR A
TRAP AND TRAP ARM*
SIZE OF TRAP AND
TRAP ARM (inches)DRAINAGE FIXTURE UNIT
VALUES (DFU)
11⁄41 unit
11⁄23 units
24 units 3 6 units
48 units For SI Units: 1 inch = 25 mm
*** Exception:** On self-service laundries.
702.2 Intermittent Flow. Drainage fixture units for intermittent flow into the drainage system shall be computed on the rated discharge capacity in gallons per minute (gpm) (L/s) in accordance with Table 702.2.
TABLE 702.1(1) MAXIMUM DRAINAGE FIXTURE UNITS FOR A
TRAP AND TRAP ARM*
CPC § 814.3.1 High relevance — show source text
Condensate drain sizing for other slopes or other conditions shall be approved by the Authority Having Jurisdiction.
Air-conditioning waste pipes, 1¼ of an inch (32 mm) and larger in size, shall be constructed of materials specified in Chapter 7. Condensate waste piping less than 1¼ of an inch (32 mm) in size shall be permitted to be PVC, CPVC, PE, PP, copper, or other rigid materials approved by the Authority Having Jurisdiction.
814.3.1 Cleanouts. Condensate drain lines shall be configured or provided with a cleanout to permit the clearing of blockages and for maintenance without requiring the drain line to be cut. 814.4 Appliance Condensate Drains. Condensate drain lines from individual condensing appliances shall be sized as required by the manufacturer’s instructions. Condensate drain lines serving more than one appliance connecting to a common indirect waste pipe shall have the connections to the indirect waste pipe protected by a sanitary waste valve complying with ASME A112.18.8, condensate trap complying with IAPMO IGC 196, or trap with a trap primer. 814.5 Point of Discharge. Air-conditioning condensate waste pipes shall connect indirectly to the drainage system through an air gap or air break to trapped and vented receptors, dry wells, mop sinks, leach pits, or the tailpiece of plumbing fixtures. An individual condensate drain shall be trapped in accordance with the appliance manufacturer’s instructions or in accordance with Section 814.4.
TABLE 814.3
MINIMUM CONDENSATE PIPE SIZE
For SI units: 1 ton of refrigerant = 3.52 kW, 1 inch = 25 mm
For SI units: °C = (°F-32)/1.8
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INDIRECT WASTES
814.6 Condensate Waste from Air-Conditioning Coils. Where the condensate waste from air-conditioning coils discharges by direct connection to a lavatory tailpiece or to an approved accessible inlet on a bathtub overflow, the connection shall be located in the area controlled by the same person controlling the air-conditioned space. 814.7 Plastic Fittings. Female plastic screwed fittings shall be used with male plastic fittings and plastic threads.
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CALIFORNIA PLUMBING CODE – MATRIX ADOPTION TABLE
CHAPTER 9 - VENTS
(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 § 811.3 High 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 § 901.1 High relevance — show source text
901.1 Applicability. This chapter shall govern the materials, design, and installation of plumbing vent systems. 901.2 Vents Required. Each plumbing fixture trap, except as otherwise provided in this code, shall be protected against siphonage and backpressure, and air circulation shall be ensured throughout all parts of the drainage system by means of vent pipes installed in accordance with the requirements of this chapter and as otherwise required by this code. 901.3 Trap Seal Protection. The vent system shall be designed to prevent a trap seal from being exposed to a pressure differential that exceeds 1 inch water column (0.24 kPa) on the outlet side of the trap.
902.0 Vents Not Required.
902.1 Interceptor. Vent piping shall be permitted to be omitted on an interceptor where such interceptor acts as a primary settling tank and discharges through a horizontal indirect waste pipe into a secondary interceptor. The second interceptor shall be properly trapped and vented. 902.2 Bars, Soda Fountains, and Counter. Traps serving sinks that are part of the equipment of bars, soda fountains, and counters need not be vented where the location and construction of such bars, soda fountains, and counters are such as to make it impossible to do so. Where such conditions exist, said sinks shall discharge using approved indirect waste pipes into a floor sink or other approved type of recep tor.
903.0 Materials.
903.1 Applicable Standards. Vent pipe and fittings shall comply with the applicable standards referenced in Table 701.2, except that:
(1) No galvanized steel or 304 stainless steel pipe shall be installed underground and shall be not less than 6 inches (152 mm) aboveground.
(2) ABS and PVC DWV piping installations shall be in accordance with the firestop protection requirements in the California Building Code . Except for individual single-family dwelling units, materials exposed within ducts or plenums shall have a flame-spread index of not more than 25 and a smoke-developed index of not more than 50 where tested in accordance with ASTM E84 or UL 723. Plastic piping installed in plenums shall be tested in accordance with all requirements of ASTM E84 or UL 723. Mounting methods, supports and sample sizes of materials for testing that are not specified in ASTM E84 or UL 723 shall be prohibited.
903.1.1 [HCD 1 & HCD 2] ABS or PVC installations are limited to not more than two stories of areas of resi- dential accommodation.
903.1.2 [HCD 1] All malleable iron vents shall be gal- vanized.
903.1.3 [OSHPD 1, 2, 3, 4 & 5] ABS and PVC instal- lations are not allowed.
903.2 Use of Copper or Copper Alloy Tubing. Copper or copper alloy tube for underground drainage and vent piping shall have a weight of not less than that of copper or copper alloy drainage tube type DWV. 903.2.1 Aboveground. Copper or copper alloy tube for aboveground drainage and vent piping shall have a weight of not less than that of copper or copper alloy drainage tube type DWV. 903.2.2 Prohibited Use. Copper or copper alloy tube shall not be used for chemical or industrial wastes as
defined in Section 811.0.
CPC § 814.3 High relevance — show source text
814.3 Condensate Waste Pipe Material and Sizing. Condensate waste pipes from air-cooling coils shall be sized in accordance with the equipment capacity as specified in Table 814.3. The material of the piping shall comply with the pressure and temperature rating of the appliance or equipment and shall be approved for use with the liquid being discharged.
TABLE 814.3
MINIMUM CONDENSATE PIPE SIZE
EQUIPMENT CAPACITY IN TONS
OF REFRIGERATIONMINIMUM CONDENSATE PIPE
DIAMETER
(inches)Up to 20 3⁄4
21 – 401
41 – 9011⁄4
91 – 12511⁄2
126 – 2502 For SI units: 1 ton of refrigerant = 3.52 kW, 1 inch = 25 mm
The size of condensate waste pipes is for one unit or a combination of units, or as recommended by the manufacturer. The capacity of waste pipes assumes a [1] ⁄ 8 inch per foot (10.4 mm/m) or 1 percent slope, with the pipe running threequarters full at the following pipe conditions:
Outside Air – 20% Col2 Room Air – 80% Col4
DBWB DB WB
90°F73°F 75°F 62.5°FFor SI units: °C = (°F-32)/1.8
Condensate drain sizing for other slopes or other conditions shall be approved by the Authority Having Jurisdiction.
Air-conditioning waste pipes, 1¼ of an inch (32 mm) and larger in size, shall be constructed of materials specified in Chapter 7. Condensate waste piping less than 1¼ of an inch (32 mm) in size shall be permitted to be PVC, CPVC, PE, PP, copper, or other rigid materials approved by the Authority Having Jurisdiction.
814.3.1 Cleanouts. Condensate drain lines shall be configured or provided with a cleanout to permit the clearing of blockages and for maintenance without requiring the drain line to be cut. 814.4 Appliance Condensate Drains. Condensate drain lines from individual condensing appliances shall be sized as required by the manufacturer’s instructions. Condensate drain lines serving more than one appliance connecting to a common indirect waste pipe shall have the connections to the indirect waste pipe protected by a sanitary waste valve complying with ASME A112.18.8, condensate trap complying with IAPMO IGC 196, or trap with a trap primer. 814.5 Point of Discharge. Air-conditioning condensate waste pipes shall connect indirectly to the drainage system through an air gap or air break to trapped and vented receptors, dry wells, mop sinks, leach pits, or the tailpiece of plumbing fixtures. An individual condensate drain shall be trapped in accordance with the appliance manufacturer’s instructions or in accordance with Section 814.4.
TABLE 814.3
MINIMUM CONDENSATE PIPE SIZE
For SI units: 1 ton of refrigerant = 3.52 kW, 1 inch = 25 mm
CPC § 1.3.4.1 High relevance — show source text
(1) Category 1 spaces
(2) Category 2 spaces
(3) Category 3 spaces
(4) Category 4 spaces [NFPA 99:1.3.4.1]
1302.3 Anesthesia. It shall be the responsibility of the health care facility’s governing body to designate anesthetizing locations. [NFPA 99:1.3.4.2]
1302.4 Wet Procedure Locations. It shall be the responsibility of the health care facility’s governing body to designate wet procedure locations. [NFPA 99:1.3.4.3]
1303.0 Health Care Facilities.
1303.1 Drinking Fountain Control Valves. Drinking fountain control valves shall be flush-mounted or fully recessed where installed in corridors or other areas where patients are transported on a gurney, bed, or wheelchair.
1303.2 Psychiatric Patient Rooms. Piping and drain traps in psychiatric patient rooms shall be concealed. Fixtures and fittings shall be resistant to vandalism.
2025 CALIFORNIA PLUMBING CODE 275
), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.
HEALTH CARE FACILITIES AND MEDICAL GAS AND MEDICAL VACUUM SYSTEMS
1303.3 Locations for Ice Storage. Ice makers or ice storage containers shall be located in nursing stations or similarly supervised areas to minimize potential contamination.
1303.4 Sterilizers and Bedpan Steamers. Sterilizers and bedpan steamers shall be installed in accordance with the manufacturer’s installation instructions and comply with Section 1303.4.1 and Section 1303.4.2.
1303.4.1 Drainage Connections. Sterilizers and bedpan steamers shall be connected to the sanitary drainage system through an air gap in accordance with Section 801.2. The size of indirect waste piping shall be not less than the size of the drain connection on the fixture. Each such indirect waste pipe shall not exceed 15 feet (4572 mm) in length and shall be separately piped to a receptor. Such receptors shall be located in the same room as the equipment served. Except for bedpan steamers, such indirect waste pipes shall not require traps. A trap having a seal of not less than 3 inches (76 mm) shall be provided in the indirect waste pipe for a bedpan
steamer.
1303.4.2 Vapor Vents and Stacks. Where a sterilizer or bedpan steamer has provision for a vapor vent and such a vent is required by the manufacturer, the vent shall be extended to the outdoors above the roof. Sterilizer and bedpan steamer vapor vents shall be installed in accordance with the manufacturer’s installation instructions and shall not be connected to a drainage system vent.
1303.5 Aspirators. Provisions for aspirators or other watersupplied suction devices shall be installed with the specific approval of the Authority Having Jurisdiction. Where aspirators are used for removing body fluids, they shall include a collection container to collect liquids and solid particles. Aspirators shall indirectly discharge to the sanitary drainage system through an air gap in accordance with Section 806.1. The potable water supply to an aspirator shall be protected by a vacuum breaker or equivalent backflow protection device in accordance with Section 603.5.9.
1303.6 Drains. Drains shall be installed on dryers, aftercoolers, separators, and receivers.
CPC § 2.875 High relevance — show source text
Table 9 Data and Material Codes for PVC Swedge Reducers [1]
Reducer
Size
(inches)Dimensions (inches) Col3 Col4 Col5 Material
CodeReducer
Size
(inches)Minimum Length Minimum Length Typical Belled End ID Typical Belled End ID Typical Belled End ID Reducer
Size
(inches)A B C D D 3 x 2 2.875 1.750 3.515 2.393 018585 4 x 3 3.375 2.875 4.515 3.515 018584 5 x 4 4.000 3.375 5.593 4.515 360777 6 x 5 5.000 4.000 6.658 5.593 360778 1 � Both belled ends must be chamferred 0.3 inches (min) by 45 .
062288 Page 6 of 20 Rev. #20: 03−25−22
UG-1: Conduits Greenbook Underground Conduits
PVC and HDPE Conduit and Fittings (continue)
Table 10 High Density Polyethylene (HDPE) Conduit Directional
Figure 9 HDPE Conduit
Figure 10 PE Mechanical Coupling
Figure 11 PVC (Bore-Gard, Schedule 40
Table 10 High Density Polyethylene (HDPE) Condu Boring Conduit 1 Col2 Col3 Col4 uit Directional Col6 Conduit Conduit Conduit Conduit Mechanical
Couplings2, 3Mechanical
Couplings2, 3Size Length
(feet)Description Material
CodeSize
(inches)Material
Code2” Sch 80 500 Coil4 360511 2 360690 2” Sch 80 40 Stick 360017 360017 360017 3” Sch 80 500 Coil4 360644 3 360691 3” Sch 80 40 Stick 360018 360018 360018 4” Sch 80 625 Coil5 360014 4 360692 4” Sch 80 40 Stick 360015 360015 360015 5” SDR 13.5 450 Coil5 360012 5 360694 5” SDR 13.5 40 Stick 360013 360013 360013 6” SDR 13.5 450 Coil5 360010 6 360695 6” SDR 13.5 40 Stick 360011 360011 360011 1 Color must be black with at least 3 red longitudinal strips. 2 May be used to connect PE conduit to PVC conduit (except in directional drilling apps.) 3 Mechanical couplings are not designed for directional drilling. Fusion joints are required. 4 No reel. 5 With reel.
Table 11 PVC (Bore-Gard) Directional Boring Conduit
Frequently asked questions
Can I use PVC for all indirect waste piping?
Maybe — materials must be approved by the AHJ and must be suitable for the liquid and temperatures discharged (see § 803.1). Specific materials rules (for condensate or chemical wastes) may require particular materials; see § 814.3 and Chapter 7 where applicable.
If an equipment drain outlet is 1/2", can I run 1/2" indirect waste?
It depends. For general indirect wastes the Code allows runs not less than the drain/tailpiece and in no case less than 1/2" (see § 803.3). But if the appliance is in a food/beverage establishment and covered by § 801.3.1, a larger minimum (for example 1") may apply. Check the specific equipment section.
Do indirect‑waste traps always need to be vented?
No. Indirect waste pipes exceeding 5 ft but less than 15 ft must be directly trapped, and those traps need not be vented, per § 803.3.
Are cleanouts required for indirect waste piping?
Yes. Angles and changes of direction in indirect waste pipes shall be provided with cleanouts to permit flushing and cleaning — § 803.3.
Which is controlling — the general § 803.3 minimum or the food‑service § 801.3.1 minimum?
The more specific provision governs. For equipment listed in § 801.3 (food & beverage handling establishments), § 801.3.1 sets explicit minimum sizes and length limits that control over the general § 803.3 language.
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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