CPC · California Plumbing Code

What are the pretreatment, materials and venting requirements for chemical/industrial indirect wastes?

If your facility produces chemical or industrial liquid wastes that could harm sewers or treatment plants, the California Plumbing Code requires you to pretreat those wastes, use approved corrosion‑resistant piping (copper is prohibited), keep chemical vents completely separate from other vent systems, and obtain AHJ approval for discharge and pretreatment plans (see §§ 811.1, 811.2, 811.6, 811.7) .

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Last reviewed: July 6, 2026

What the code requires — 2-4 sentences

The California Plumbing Code requires that chemical or liquid industrial wastes that could damage sewers, interfere with sewage treatment, or contaminate waters be pretreated before being discharged into the drainage system (§ 811.1) . Waste and vent piping that receive corrosive or acidic discharges must be constructed of approved corrosion‑resistant materials (listed in § 811.2) and joining materials must be approved for the service (see § 811.3) . Chemical vents must be kept separate from vents for other services (no intersections) per § 811.6, and final discharge of chemical wastes must be in a manner approved by the Authority Having Jurisdiction (AHJ) per § 811.7 .

The single most important rule: if a chemical or industrial liquid waste is likely to harm the sewer system, it must be rendered innocuous by approved pretreatment before it may enter the drainage system (see § 811.1) .

Requirements in detail

Pretreatment (purpose, approval, documentation)

  • Requirement: Pretreatment is required for chemical or liquid industrial wastes that are likely to (1) damage or increase maintenance costs on the sanitary sewer, (2) detrimentally affect sewage treatment, or (3) contaminate surface or subsurface waters — they "shall be pretreated to render them innocuous" before discharge (§ 811.1) .
  • AHJ control: The AHJ shall require detailed construction documents for the pretreatment facilities and must be satisfied with piping design and materials from the point of origin to the pretreatment facility (§ 811.1) .
  • Owner record: The owner must keep a permanent record of the location of piping and venting carrying chemical waste (see § 811.5) .

Materials and construction (what you must use)

  • Prohibited material: Copper or copper alloy tube shall not be used for chemical or industrial wastes as defined in this section (§ 811.1) .
  • Approved materials for waste and vent piping that receive acid/corrosive discharges include: CPVC, polypropylene (PP), polyvinylidene fluoride (PVDF), chemical‑resistant glass, high‑silicon iron pipe, lead pipe with minimum wall thickness, ceramic (glazed or unglazed) vitrified clay, or other AHJ‑approved corrosion‑resistant materials (§ 811.2) .
  • Minimum lead wall thickness: not less than 1/8 inch (3.2 mm) for lead pipe used for chemical/acid service (§ 811.2) .
  • Standards: Specific pipe types must meet standards where listed: CPVC — ASTM F2618; PP — ASTM F1412 or CSA B181.3; PVDF — ASTM F1673 or CSA B181.3; chemical‑resistant glass — ASTM C1053; high‑silicon iron — ASTM A861 (§ 811.2) .
  • Joining and access: Joining materials shall be of approved type and quality (see § 811.3) and piping should be readily accessible where practicable with maximum clearance from other services (§ 811.4) .

Venting and discharge

  • Chemical vents: No chemical vent shall intersect vents for other services — chemical venting must be segregated from other vent systems (§ 811.6) .
  • Discharge approval: Chemical wastes shall be discharged in a manner approved by the Authority Having Jurisdiction — AHJ approval is required for disposal method and point of discharge (§ 811.7) .

Quick reference table — decision dimensions and code references

Decision item Key value / requirement Code Reference
When is pretreatment required When wastes are likely to damage sewers, affect sewage treatment, or contaminate waters — must be rendered innocuous prior to discharge § 811.1
Materials prohibited Copper or copper alloy tubing not permitted for chemical/industrial wastes § 811.1
Approved pipe materials (examples) CPVC, PP, PVDF, chemical‑resistant glass, high‑silicon iron, lead (min 1/8 in wall), ceramic vitrified clay, or AHJ‑approved § 811.2
Applicable standards CPVC — ASTM F2618; PP — ASTM F1412 or CSA B181.3; PVDF — ASTM F1673 or CSA B181.3; glass — ASTM C1053; high‑silicon iron — ASTM A861 § 811.2
Venting rule Chemical vent shall not intersect vents for other services § 811.6
Discharge approval Chemical wastes discharged only in manner approved by AHJ § 811.7
Record keeping Owner must keep permanent record of piping & vent locations carrying chemical waste § 811.5
Minor/diluted exceptions Materials/methods provisions do not apply to small, adequately diluted discharges in photographic/X-ray darkrooms or research labs (minor amounts) § 811.8

Exceptions & special cases

  • Diluted chemical discharges in small quantities (e.g., photographic or x‑ray darkrooms, some research or control labs) are excepted from the materials/methods provisions of § 811 (they are not subject to the strict material requirements) provided the amounts are minor and adequately diluted — see § 811.8 .
  • AHJ discretion: The AHJ has authority to require detailed pretreatment plans and to approve alternative materials or methods if shown to be safe and effective (§ 811.1, § 811.7) .
  • Interrelationships: Indirect waste rules elsewhere in Chapter 8 (for example, sizing, traps, air gap/air break) also apply to indirect waste piping carrying chemical wastes — check those sections when planning routing and receptors (see related provisions list below) .

Common mistakes

  • Installing copper tubing for corrosive/chemical wastes (explicitly prohibited) — violates § 811.1 .
  • Using standard PVC or other non‑approved materials instead of CPVC/PP/PVDF/high‑silicon iron/chem‑resistant glass/ceramic or AHJ‑approved alternatives required by § 811.2 .
  • Connecting a chemical vent into a building vent stack or other vent system (i.e., intersection) — violates § 811.6 .
  • Failing to secure AHJ approval for the pretreatment facility or for the final method of discharge — necessary under § 811.1 and § 811.7 .
  • Omitting a permanent record of chemical piping/venting locations — required by § 811.5 .

Worked example — laboratory sink that discharges an acidic process waste

Scenario: A lab produces an intermittent acidic rinse stream that is likely to increase sewer maintenance if discharged untreated. The lab’s waste receptor is 12 feet from the sink.

  1. Pretreatment decision: Because the stream is "likely to damage or increase maintenance costs on the sanitary sewer system," the lab must provide a pretreatment system to render the waste innocuous before discharge; the AHJ will require detailed construction documents for that pretreatment facility (§ 811.1) .
  2. Piping material: The drain and any vent conveying undiluted acidic waste must be built from an approved corrosion‑resistant material, for example CPVC (to ASTM F2618), PVDF (ASTM F1673), or chemical‑resistant glass (ASTM C1053); copper is not allowed (§ 811.2, § 811.1) .
  3. Lead pipe option: If the designer proposes lead pipe, confirm wall thickness is at least 1/8 in (3.2 mm) as required by § 811.2 and get AHJ approval .
  4. Venting: The chemical vent for this waste line must not intersect other vent systems — keep it separate and extend as required by AHJ (§ 811.6) .
  5. Documentation & approval: Submit pretreatment plans and materials specs to AHJ and ensure the owner keeps the required permanent record of the chemical piping and venting locations (§ 811.1, § 811.5, § 811.7) .

Note: If the lab’s indirect waste piping raises other Chapter 8 issues (trap type, indirect receptor, air gap/air break, or maximum developed length), consult the corresponding Chapter 8 sections (for example § 803.3 for indirect waste pipe length and trapping) in addition to the chemical‑waste rules cited above .

Related provisions

  • § 811.1 — Pretreatment requirement and AHJ documentation (chemical wastes)
  • § 811.2 — Materials allowed for waste and vent pipes for chemical/acid service (and referenced standards)
  • § 811.6 — Chemical vent separation (no intersection with other vents)
  • § 811.7 — Discharge must be approved by the AHJ
  • § 811.3 — Joining materials must be approved (related to materials)
  • § 811.4 — Accessibility and clearance for chemical piping
  • § 811.5 — Owner permanent record requirement for chemical piping and venting locations
  • § 811.8 — Exception for minor, adequately diluted discharges (photographic, x‑ray, some labs)
  • § 803.3 — Indirect waste pipe sizing/length and venting requirements (useful cross‑reference)

Code references

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

  • CPC § 810.3 High relevance — show source text

    810.3 Cleaning. Sumps and condensers shall be provided with suitable means of access for cleaning and shall contain a volume of not less than twice the volume of water removed

    from the boiler or boilers connected to it where the normal

    water level of such boiler or boilers is reduced not less than 4 inches (102 mm).

    810.4 Strainers. An indirect waste interceptor is receiving discharge-containing particles that would clog the receptor drain shall have a readily removable beehive strainer.

    811.0 Chemical Wastes.

    811.1 Pretreatment. Chemical or liquid industrial wastes that are likely to damage or increase maintenance costs on the sanitary sewer system, detrimentally affect sewage treatment or contaminate surface or subsurface waters shall be pretreated to render them innocuous before discharge into a drainage system. Detailed construction documents of the pretreatment facilities shall be required by the Authority Having Jurisdiction.

    Piping conveying industrial, chemical, or process wastes from their point of origin to sewer-connected pretreatment facilities shall be of such material and design as to adequately perform its intended function to the satisfaction of the Authority Having Jurisdiction. Drainage discharge piping from pre

    treatment facilities or interceptors shall be in accordance with standard drainage installation procedures.

    Copper or copper alloy tube shall not be used for chemical or industrial wastes as defined in this section.

    811.2 Waste and Vent Pipes. Each waste pipe receiving or intended to receive the discharge of a fixture into which acid or corrosive chemical is placed, and each vent pipe connected thereto, shall be constructed of chlorinated polyvinyl chloride (CPVC), polypropylene (PP), polyvinylidene fluoride (PVDF), chemical-resistant glass, high-silicon iron pipe, or lead pipe with a wall thickness of not less than [1] ⁄ 8 of an inch (3.2 mm); an approved type of ceramic glazed or unglazed vitrified clay; or other approved corrosion-resistant materials. 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.

  • CPC § 810.1. High relevance — show source text

    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


    1    		 1 21⁄2


    11⁄4    		 11⁄4 3

    11⁄2    		 11⁄2 4

    2    		 2 5

    21⁄2    		 21⁄2 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.

    810.2 Sumps, Condensers, and Intercepting Tanks. Sumps, condensers, or intercepting tanks that are constructed of concrete shall have walls and bottom, not less than 4 inches (102 mm) in thickness, and the inside shall be cement plastered not less than [1] ⁄ 2 of an inch (12.7 mm) in thickness. Condensers constructed of metal shall be not less than No. 12 U.S. standard gauge (0.109 inch) (2.77 mm), and such metal condensers shall be protected from external corrosion by an approved bituminous coating.

    810.3 Cleaning. Sumps and condensers shall be provided with suitable means of access for cleaning and shall contain a volume of not less than twice the volume of water removed

    from the boiler or boilers connected to it where the normal

    water level of such boiler or boilers is reduced not less than 4 inches (102 mm).

    810.4 Strainers. An indirect waste interceptor is receiving discharge-containing particles that would clog the receptor drain shall have a readily removable beehive strainer.

    811.0 Chemical Wastes.

    811.1 Pretreatment. Chemical or liquid industrial wastes that are likely to damage or increase maintenance costs on the sanitary sewer system, detrimentally affect sewage treatment or contaminate surface or subsurface waters shall be pretreated to render them innocuous before discharge into a drainage system. Detailed construction documents of the pretreatment facilities shall be required by the Authority Having Jurisdiction.

    Piping conveying industrial, chemical, or process wastes from their point of origin to sewer-connected pretreatment facilities shall be of such material and design as to adequately perform its intended function to the satisfaction of the Authority Having Jurisdiction. Drainage discharge piping from pre

    treatment facilities or interceptors shall be in accordance with standard drainage installation procedures.

  • CPC § 808.0 High relevance — show source text

    808.0 Cooling Water . . . . . . . . . . . . . . . .182

    808.1 General . . . . . . . . . . . . . . . . . . . . .182

    809.0 Drinking Fountains . . . . . . . . . . . .182

    809.1 General . . . . . . . . . . . . . . . . . . . . .182

    810.0 Steam and Hot Water Drainage Condensers and Sumps . . . . . . . .182

    810.1 High-Temperature Discharge . . . .182

    Table 810.1 Pipe Connections in Blowoff Condensers and Sumps . . . . . . . .183

    810.2 Sumps, Condensers, and Intercepting Tanks . . . . . . . . . . . .183

    810.3 Cleaning . . . . . . . . . . . . . . . . . . . .183

    810.4 Strainers . . . . . . . . . . . . . . . . . . . .183

    811.0 Chemical Wastes . . . . . . . . . . . . .183

    811.1 Pretreatment . . . . . . . . . . . . . . . . .183

    811.2 Waste and Vent Pipes . . . . . . . . .183

    811.3 Joining Materials . . . . . . . . . . . . . .183

    811.4 Access . . . . . . . . . . . . . . . . . . . . .183

    811.5 Permanent Record . . . . . . . . . . . .183

    811.6 Chemical Vent . . . . . . . . . . . . . . .183

    811.7 Discharge . . . . . . . . . . . . . . . . . . .183

    811.8 Diluted Chemicals . . . . . . . . . . . . .183

    812.0 Clear Water Wastes . . . . . . . . . . .183

    812.1 General . . . . . . . . . . . . . . . . . . . . .183

    813.0 Swimming Pools . . . . . . . . . . . . . .183

    813.1 General . . . . . . . . . . . . . . . . . . . . .183

    814.0 Condensate Waste and Control . . .183

    814.1 Condensate Disposal . . . . . . . . . .183

    814.2 Condensate Control . . . . . . . . . . .184

    814.3 Condensate Waste Pipe Material and Sizing . . . . . . . . . . . .184

    Table 814.3 Minimum Condensate Pipe Size . . . . . . . . . . . . . . . . . . .184

    814.4 Appliance Condensate Drains . . .184

    814.5 Point of Discharge . . . . . . . . . . . .184

    814.6 Condensate Waste from

    Air-Conditioning Coils . . . . . . . . . .185

    814.7 Plastic Fittings . . . . . . . . . . . . . . .185

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    TABLE OF CONTENTS

  • CPC § 801.7 High relevance — show source text

    801.7 Drip or Drainage Outlets . . . . . . . .181

    802.0 Approvals . . . . . . . . . . . . . . . . . . .181

    802.1 General . . . . . . . . . . . . . . . . . . . . .181

    803.0 Indirect Waste Piping . . . . . . . . . .181

    803.1 Materials . . . . . . . . . . . . . . . . . . . .181

    803.2 Copper and Copper Alloys . . . . . .181

    803.3 Pipe Size and Length . . . . . . . . . .181

    804.0 Indirect Waste Receptors . . . . . . .182

    804.1 Standpipe Receptors . . . . . . . . . .182

    805.0 Pressure Drainage Connections . . . . . . . . . . . . . . . . .182

    805.1 General . . . . . . . . . . . . . . . . . . . . .182

    806.0 Sterile Equipment . . . . . . . . . . . . .182

    806.1 General . . . . . . . . . . . . . . . . . . . . .182

    807.0 Appliances . . . . . . . . . . . . . . . . . .182

    807.1 Non-Classed Apparatus . . . . . . . .182

    807.2 Undiluted Condensate Waste . . . .182

    807.3 Domestic Dishwashing Machine . . . . . . . . . . . . . . . . . . . .182

    808.0 Cooling Water . . . . . . . . . . . . . . . .182

    808.1 General . . . . . . . . . . . . . . . . . . . . .182

    809.0 Drinking Fountains . . . . . . . . . . . .182

    809.1 General . . . . . . . . . . . . . . . . . . . . .182

    810.0 Steam and Hot Water Drainage Condensers and Sumps . . . . . . . .182

    810.1 High-Temperature Discharge . . . .182

    Table 810.1 Pipe Connections in Blowoff Condensers and Sumps . . . . . . . .183

    810.2 Sumps, Condensers, and Intercepting Tanks . . . . . . . . . . . .183

    810.3 Cleaning . . . . . . . . . . . . . . . . . . . .183

    810.4 Strainers . . . . . . . . . . . . . . . . . . . .183

    811.0 Chemical Wastes . . . . . . . . . . . . .183

    811.1 Pretreatment . . . . . . . . . . . . . . . . .183

    811.2 Waste and Vent Pipes . . . . . . . . .183

    811.3 Joining Materials . . . . . . . . . . . . . .183

    811.4 Access . . . . . . . . . . . . . . . . . . . . .183

    811.5 Permanent Record . . . . . . . . . . . .183

    811.6 Chemical Vent . . . . . . . . . . . . . . .183

  • CPC § 1.11.0. Medium 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 § 803.0 Medium 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 § 803.3 Medium relevance — show source text

    Vents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .803.3

    Where required . . . . . . . . . . . . . . . . . . . . . . . . . . .801.2

    INDIVIDUAL VENTS . . . . . . . . . . .211.0, Table 703.2, 904.1,

    908.2.1

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    INDEX

    INDUSTRIAL WASTES

    Access . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .811.4

    Approval required . . . . . . . . . . . . . . . . . . . . . . . . . .811.1

    Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .211.0

    Disposal . . . . . . . . . . . . . . . . . . . . . . . . . . .306.0, 811.7 Materials . . . . . . . . . . . . . . . . . . . . .811.2, 811.3, 903.2.2

    Pretreatment required . . . . . . . . . . . . . . . . .306.1, 811.1 Prohibited material . . . . . . . . . . . . . . . . . .811.1, 903.2.2

    Vents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .811.6

    INSANITARY

    Defective systems . . . . . . . . . . . . . . . . . . . . . . . .105.3.1

    Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .211.0

    Health and safety . . . . . . . . . . . . . . . . . . . . . . . . .102.5

    INSPECTION AND TESTING . . . . . . . . . . . . . . . . . . . .105.0

    Alternative engineering design . . . . .301.3.1 – 301.3.1.2,

    301.5.6

    Cross-Connection . . . . . . . . . . . . . . . . . . . . . .1505.14.2

    Final . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .105.2

    Periodic . . . . . . . . . . . . . . . . . . . . . . . . . . . .1505.14.2.4

  • 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

    2025 CALIFORNIA PLUMBING CODE 183

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

    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 § 8-903.2 Medium relevance — show source text

    8-903.2 Residential occupancies.

    8-903.2.1 Where toilet facilities are provided, alternative sewage disposal methods may be acceptable if approved by the local health department. In hotels, where private facilities are not provided, water closets at the ratio of one for each 15 rooms may be acceptable.

    8-903.2.2 Toilet facilities are not required to be on the same floor or in the same building as sleeping rooms. Water-flush toilets may be located in a building immediately adjacent to the sleeping rooms. When alternative sewage disposal methods are utilized, they shall be located a minimum distance from the sleeping rooms or other locations as approved by the local health department.

    8-903.2.3 Kitchen sinks shall be provided in all kitchens. The sink and countertop may be of any smooth nonabsorbent finish which can be maintained in a sanitary condition.

    8-903.2.4 Hand washing facilities shall be provided for each dwelling unit and each hotel guest room. A basin and pitcher may be acceptable as adequate hand washing facilities.

    8-903.2.5 Hot or cold running water is not required for each plumbing fixture, provided a sufficient amount of water is supplied to permit the fixture’s normal operation.

    8-903.2.6 Bathtubs and lavatories with filler spouts less than 1 inch (25.4 mm) above the fixture rim may remain in use, provided there is an acceptable overflow below the rim.

    8-903.2.7 Original or salvage water closets, urinals and flushometer valves shall be permitted in qualified historical buildings or properties. Historically accurate reproduction, nonlow-consumption water closets, urinals and flushometer valves shall be permitted except where historically accurate fixtures that comply with the regular code are available.

    8-903.3 Materials. New nonhistorical materials shall comply with the regular code requirements. The enforcing agency shall accept alternative materials which do not create a safety hazard where their use is necessary to maintain the historical integrity of the building.

    8-903.4 Drainage and vent systems. Plumbing fixtures shall be connected to an adequate drainage and vent system. The enforcing agency may require operational tests for drainage and vent systems which do not comply with applicable requirements of the regular code. Vent terminations may be installed in any location which, in the opinion of the enforcing agency, does not create a safety hazard.

    8-903.5 Indirect and special wastes. Indirect and special waste systems shall be installed so that no safety hazard is created. Chemical or industrial liquid wastes which may detrimentally affect the sanitary sewer system shall be pretreated to render them safe prior to discharge.

    8-903.6 Traps and interceptors. Traps and interceptors shall comply with the regular code requirements except that the enforcing agency shall accept solutions which do not increase the safety hazard. Properly maintained “S” and drum traps may remain in use.

    8-903.7 Joints and connections.

    8-903.7.1 Joints and connections in new plumbing systems shall comply with applicable requirements of the regular code.

    8-903.7.2 Joints and connections in existing or restored systems may be of any type that does not create a safety hazard.

    8-903.8 Water distribution. Plumbing fixtures shall be connected to an adequate water distribution system. The enforcing agency may require operational tests for water distribution systems which do not comply with applicable requirements of the regular code. Prohibited (unlawful) connections and cross connections shall not be permitted.

  • CPC § 605.1.3.1 Medium relevance — show source text

    605.1.3.1, 605.1.4, 605.16.1,

    705.3.3, 705.10.1, 705.10.2

    SPACING

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

    1210.3.5.1, Table 1210.3.5.1,

    1323.4, Table 1323.4.4,

    1327.6, Table 1327.6

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

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

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

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

    SPECIAL WASTES

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

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

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

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

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

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

    SPECIFIC GRAVITY,

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

    SPECIFICATIONS

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

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

    907.0, 911.3, 1101.16.2, C 304.3,

    C 304.4, C 401.0, C 601.0

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

    605.13, Table 701.2, 705.7

    STANDPIPE,

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

    STATION INLETS

  • CPC § 8-903.3 Medium relevance — show source text

    8-903.3 Materials. New nonhistorical materials shall comply with the regular code requirements. The enforcing agency shall accept alternative materials which do not create a safety hazard where their use is necessary to maintain the historical integrity of the building.

    8-903.4 Drainage and vent systems. Plumbing fixtures shall be connected to an adequate drainage and vent system. The enforcing agency may require operational tests for drainage and vent systems which do not comply with applicable requirements of the regular code. Vent terminations may be installed in any location which, in the opinion of the enforcing agency, does not create a safety hazard.

    8-903.5 Indirect and special wastes. Indirect and special waste systems shall be installed so that no safety hazard is created. Chemical or industrial liquid wastes which may detrimentally affect the sanitary sewer system shall be pretreated to render them safe prior to discharge.

    8-903.6 Traps and interceptors. Traps and interceptors shall comply with the regular code requirements except that the enforcing agency shall accept solutions which do not increase the safety hazard. Properly maintained “S” and drum traps may remain in use.

    8-903.7 Joints and connections.

    8-903.7.1 Joints and connections in new plumbing systems shall comply with applicable requirements of the regular code.

    8-903.7.2 Joints and connections in existing or restored systems may be of any type that does not create a safety hazard.

    8-903.8 Water distribution. Plumbing fixtures shall be connected to an adequate water distribution system. The enforcing agency may require operational tests for water distribution systems which do not comply with applicable requirements of the regular code. Prohibited (unlawful) connections and cross connections shall not be permitted.

    8-903.9 Building sewers and private sewage disposal systems. New building sewers and new private sewage disposal systems shall comply with applicable requirements of the regular code.

    20 2025 CALIFORNIA HISTORICAL BUILDING CODE

    on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

    MECHANICAL, PLUMBING AND ELECTRICAL REQUIREMENTS

    8-903.10 Fuel-gas piping. Fuel-gas piping shall comply with the regular code requirements except that the enforcing agency shall accept solutions which do not increase the safety hazard.

    SECTION 8-904 — ELECTRICAL

    8-904.1 General. Electrical systems shall comply with the regular code unless otherwise permitted by this code, or approved by the authority having jurisdiction.

    8-904.1.1 The provisions of the CHBC shall apply to the acceptance, location, installation, alteration, repair, relocation, replacement or addition of any electrical system or portion thereof, the premise wiring, or equipment fixed in place as related to restoration within or attached to a qualified historical building or property.

    8-904.1.2 Existing systems, wiring methods and electrical equipment which do not, in the opinion of the enforcing agency, constitute a safety hazard may remain in use.

    8-904.1.3 The enforcing agency may approve any alternative to the CHBC which achieves equivalent safety.

    8-904.1.4 Archaic methods that do not appear in present codes may remain and may be extended if, in the opinion of the enforcing agency, they constitute a safe installation.

    8-904.2 Wiring methods.

  • CPC § 3.3.172 Medium relevance — show source text

    Special Wastes. Wastes that require some special method of handling, such as the use of indirect waste piping and receptors, corrosion-resistant piping, sand, oil or grease interceptors, condensers, or other pretreatment facilities.

    Stack. The vertical main of a system of soil, waste, or vent piping extending through one or more stories.

    Stack Vent. The extension of soil or waste stacks above the

    highest horizontal drain connected to the stack.

    Standard. A document, the main text of which contains only mandatory provisions using the word “shall” to indicate requirements and which is in a form generally suitable for mandatory reference by another standard or code or for adoption into law. Nonmandatory provisions shall be located in an appendix, footnote, or fine print note and are not to be considered a part of the requirements of a standard.

    Standard Cubic Feet per Minute (SCFM). Volumetric flow rate of gas in units of standard cubic feet per minute.

    [NFPA 99:3.3.172]

    Station Inlet. An inlet point in a piped medical/surgical vacuum distribution system at which the user makes connections and disconnections. [NFPA 99:3.3.173]

    Station Outlet. An outlet point in a piped medical gas distribution system at which the user makes connections and disconnections. [NFPA 99:3.3.174]

    Sterilizer. A piece of equipment that disinfects instruments and equipment by way of heat.

    Storm Drain. See Building Drain (Storm).

    Storm Sewer. A sewer used for conveying rainwater, surface water, condensate, cooling water, or similar liquid

    wastes.

    Submeter. [HCD 1] A secondary device beyond a meter that measures water consumption of an individual rental unit within a multiunit residential structure or mixed-use residential and

    commercial structure. (See Civil Code Section 1954.202(g) and Water Code Section 517 for additional details.)

    Subsoil Drain. A drain that collects subsurface or seepage water and conveys it to a place of disposal.

    Subsoil Irrigation Field. Gray water irrigation field installed in a trench within the layer of soil below the topsoil. This system is typically used for irrigation of deep rooted plants.

    Subsurface Irrigation Field. Gray water irrigation field installed below finished grade within the topsoil.

    Sump. An approved tank or pit that receives sewage or liquid waste and which is located below the normal grade of the gravity system and which must be emptied by mechanical

    means.

    Supports. Supports, hangers, and anchors are devices for properly supporting and securing pipe, fixtures, and equip ment.

    Surge Tank. A reservoir to modify the fluctuation in flow rates to allow for uniform distribution of gray water to the points of irrigation.

    222.0 – T –

    T Rating. The time period that the penetration firestop system, including the penetrating item, limits the maximum temperature rise of 325°F (181°C) above its initial temperature through the penetration on the nonfire side, where tested in accordance with ASTM E814 or UL 1479.

Frequently asked questions

What does "render them innocuous" mean in § 811.1?

It means the waste must be treated or neutralized so it will not damage the sanitary sewer, interfere with treatment, or contaminate waters; the AHJ will require plans and approve the pretreatment method (§ 811.1) .

Can I use standard PVC for an acid drain?

No — standard PVC is not listed among approved corrosion‑resistant materials in § 811.2. Use one of the listed materials (CPVC, PP, PVDF, chemical‑resistant glass, high‑silicon iron, lead with required wall thickness, ceramic vitrified clay, or AHJ‑approved alternatives) .

Are chemical vents allowed to join other building vents?

No. § 811.6 states that no chemical vent shall intersect vents for other services — chemical venting must be segregated and treated separately by the AHJ .

Do I always need AHJ approval to discharge chemical wastes?

Yes — § 811.7 requires chemical wastes to be discharged in a manner approved by the Authority Having Jurisdiction, and § 811.1 requires AHJ review of pretreatment construction documents .

Is there any relaxed rule for small photographic lab wastes?

Yes — the materials/methods requirements of this section do not apply to installations such as photographic or x‑ray darkrooms or research labs where minor amounts of adequately diluted chemicals are discharged (see § 811.8) .

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Related in the CPC

How must condensate be disposed of and what are the rules for condensate pumps?

How are cooling water, boiler blowoff, condensers and high‑temperature discharges handled as indirect wastes?

What appliance discharges require air gaps (dishwashers, sterilizers, drinking fountains)?

Special indirect wastes: chemical, condensate, cooling, steam, pools and appliances

California Plumbing Code