CPC · California Plumbing Code
When grease interceptors are required and maintenance obligations
If your business produces grease‑laden wastewater (sinks, floor drains, etc.), the local building/plumbing official decides whether you must install an approved grease interceptor; the CPC requires that interceptors be kept in efficient operating condition by periodic grease removal and prohibits toilets from discharging through interceptors. The code also generally bars dishwashers and ordinary food waste disposers from discharging into interceptors unless the interceptor is designed for food waste (see §1014.1, §1014.1.2, §1014.1.3) .
Last reviewed: July 6, 2026
What the code requires — plain English
- Where the Authority Having Jurisdiction determines waste pretreatment is required, an approved grease interceptor must be installed to receive drainage from fixtures or equipment that produce grease‑laden waste (see §1014.1) .
- Grease interceptors must be maintained by periodic removal of accumulated grease; removed grease must not be returned to the drainage system and the AHJ may require additional equipment or a formal maintenance program (see §1014.1.2) .
- Food waste disposers and dishwashers generally shall not discharge into a grease interceptor, except where the interceptor is specifically designed to receive food‑waste discharge (see §1014.1.3) .
If the local official says pretreatment is needed for grease‑laden waste, install an approved grease interceptor and keep it clean; the CPC lets the AHJ set the exact scope and maintenance program.
Requirements in detail
Who decides when one is required
- Decision maker: Authority Having Jurisdiction (AHJ) — the AHJ determines whether waste pretreatment (i.e., a grease interceptor) is required for a particular facility or drain line (§1014.1) .
What kinds of fixtures/equipment are covered
- Covered: fixtures and equipment that produce grease‑laden waste, including but not limited to sinks, floor drains, floor sinks, scullery/food prep sinks, pot/pan sinks and other fixtures in serving establishments (restaurants, cafeterias, hotels, hospitals, etc.) (§1014.1) .
- Not covered: individual dwelling units / private living quarters — a grease interceptor is not required for these (§1014.1) .
- Prohibited flows: water closets, urinals, and other fixtures conveying human waste shall not drain into or through the grease interceptor (§1014.1) .
Installation / plumbing connections (summary)
- Each fixture discharging into a grease interceptor must be individually trapped and vented in an approved manner (see §1014.1.1, referenced in the CPC text adjacent to §1014.1) .
- The CPC allows hydromechanical, gravity, or engineered systems where space/physical constraints exist; sizing and installation rules are in other subsections (see Related Provisions below) (§1014.1) .
Maintenance obligations
- Grease interceptors must be maintained in efficient operating condition by periodic removal of accumulated grease and solids; the CPC does not fix a specific interval — only that the removal must be periodic and that removed grease must not be discharged back into the sewer (§1014.1.2) .
- If the AHJ finds the interceptor is not being properly cleaned or maintained, the AHJ may require additional equipment and may mandate a maintenance program (§1014.1.2) .
Food waste disposers and dishwashers
- No food waste disposer or dishwasher shall be connected to or discharge into a grease interceptor under the general rule (§1014.1.3) .
- Exception: food waste disposers are permitted to discharge to grease interceptors specifically designed to receive food waste; commercial disposers may be allowed to discharge directly into the building drainage where permitted (§1014.1.3) .
Decision table — quick reference
| Decision dimension | Key value / threshold | How to apply | Code Reference |
|---|---|---|---|
| Who decides requirement | Authority Having Jurisdiction | AHJ determines whether waste pretreatment is required | §1014.1 |
| Which fixtures | Grease‑laden waste fixtures (sinks, floor drains, scullery, etc.) | Interceptor required where these drain and AHJ requires pretreatment | §1014.1 |
| Residential exceptions | Individual dwelling units / private living quarters | Interceptor not required | §1014.1 |
| Human‑waste fixtures | Toilets / urinals | Shall not drain into/through grease interceptor | §1014.1 |
| Plumbing condition for each fixture | Individually trapped and vented | Each fixture discharging to interceptor must be trapped and vented | §1014.1.1 (adjacent to §1014.1) |
| Maintenance frequency | Periodic removal (frequency not specified) | Owner/operator must remove accumulated grease periodically; AHJ can mandate schedule | §1014.1.2 |
| Food waste disposers | Generally prohibited to discharge into interceptor | Allowed only if interceptor is designed to receive food waste | §1014.1.3 |
Exceptions & special cases
- The CPC gives the AHJ latitude to require interceptors only where needed — there is no automatic universal requirement; the AHJ may also accept engineered or alternative systems when space/constraints exist (§1014.1) .
- Commercial food waste disposers may discharge directly into the building drainage where allowed, but dishwashers and ordinary food waste disposers generally must not discharge to a grease interceptor unless the interceptor is designed for food‑waste discharge (§1014.1.3) .
- The CPC explicitly exempts individual dwelling units from interceptor requirements; do not assume a multi‑unit building is exempt (the language limits the exemption to private living quarters) (§1014.1) .
Common mistakes
- Treating the CPC as prescriptive about when — the code delegates the threshold decision to the AHJ; don’t assume a grease interceptor is always required for a given use without AHJ confirmation (§1014.1) .
- Assuming the CPC specifies a fixed cleaning interval — it requires periodic removal but does not set the interval; the AHJ can require a maintenance program if cleaning is inadequate (§1014.1.2) .
- Hooking a dishwasher or ordinary food waste disposer into a grease interceptor without verifying the interceptor is designed for food waste — that’s prohibited unless explicitly allowed by design (§1014.1.3) .
- Allowing toilets/urinals to discharge through interceptors — the CPC forbids that flow path (§1014.1) .
Worked example
Scenario: A 1,200 sf café with a 3‑compartment pot sink, a prep sink, a mop sink, and two floor drains. The local plumbing inspector (AHJ) inspects and determines grease pretreatment is required.
Step 1 — Determine coverage: All sinks and floor drains that produce grease‑laden waste are in scope; toilets are excluded from interceptor plumbing (§1014.1) .
Step 2 — Install approved interceptor: The owner installs an approved grease interceptor sized per the applicable CPC sizing rules (sizing rules are in other CPC subsections; §1014.1 requires an approved type be installed where AHJ determines pretreatment is required) (§1014.1) .
Step 3 — Maintenance plan: The café operator commits to a vendor schedule to pump and remove accumulated grease every 60 days. The CPC requires periodic removal but does not mandate 60 days — the AHJ reviews the plan and accepts it or mandates a different frequency; the CPC notes the AHJ may mandate a maintenance program if the interceptor is not properly cleaned (§1014.1.2) .
Step 4 — Dishwashers / disposers: If the café intends to use a food waste disposer, the owner must ensure the interceptor is designed to receive food waste before connecting; otherwise the disposer must discharge elsewhere per §1014.1.3 .
Related provisions (for design, sizing and installation)
- §1014.2 — Hydromechanical grease interceptor requirements and sizing references (see CPC Table 1014.2.1) .
- §1014.3 — Gravity grease interceptor design, location, sizing (Table 1014.3.6) and construction requirements .
- §1009.6 — General maintenance requirement for interceptors/clarifiers (periodic removal of grease, scum, oil, solids) .
- §1015 — FOG disposal systems (purpose, performance and design standards) — relevant when AHJ allows FOG systems as an alternative .
- Appendix/H sections and local public‑works rules may further specify sampling, access, manholes, or mandatory schedules — always verify with the AHJ and local sewer agency (see CPC Appendix H and local codes) .
Code references
Grounded in the retrieved California Plumbing Code — click a citation to read the verbatim passage:
CPC § 1014.3.6 High relevance — show source text
1014.3.6, shall be installed in accordance with the manufacturer’s installation instructions to receive the drainage from fixtures or equipment that produce grease-laden waste. Grease-laden waste fixtures shall include, but not be limited to, sinks and drains, such as floor drains, floor sinks, and other fixtures or equipment in serving establishments, such as restaurants, cafes, lunch counters, cafeterias, bars and clubs, hotels, hospitals, sanitariums, factory or school kitchens, or other establishments where grease is introduced into the drainage or sewage system in quantities that can effect line stoppage or hinder sewage treatment or private sewage disposal systems. A combination of hydromechanical, gravity grease interceptors and engineered systems shall be allowed to meet this code and other applicable requirements of the Authority Having Jurisdiction where space or existing physical constraints of existing buildings necessitate such installations. A grease interceptor shall not be required for individual dwelling units or private living quarters. Water closets, urinals, and other plumbing fixtures conveying human waste shall not drain into or through the grease interceptor.
1014.1A [OSHPD 1, 1R, 2, 3, 4 & 5] The Authority Having Jurisdiction is the individual official, board, department or agency authorized to administer and enforce the sewage treatment system in the area of the location of the health facil- ity.
1014.1B [OSHPD 1, 1R, 2, 3, 4 & 5] Grease interceptors shall not be installed in food preparation area of the kitchens.
1014.1C [OSHPD 1, 1R, 2, 3, 4 & 5] Grease interceptors shall be installed outside of the kitchen area in location affording ease of maintenance and servicing.
2025 CALIFORNIA PLUMBING CODE 197
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TRAPS AND INTERCEPTORS
1014.1.1 Trapped and Vented. Each fixture discharging into a grease interceptor shall be individually trapped and vented in an approved manner.
1014.1.2 Maintenance. Grease interceptors shall be maintained in efficient operating condition by periodic removal of the accumulated grease and latent material. No such collected grease shall be introduced into drainage piping or a public or private sewer. Where the Authority Having Jurisdiction determines that a grease interceptor is not being properly cleaned or maintained, the Authority Having Jurisdiction shall have the authority to mandate the installation of additional equipment or devices and to mandate a maintenance program.
1014.1.3 Food Waste Disposers and Dishwash- ers. No food waste disposer or dishwasher shall be connected to or discharge into a grease interceptor. Commercial food waste disposers shall be permitted to discharge directly into the building’s drainage system.
Exception: Food waste disposers shall be permitted to discharge to grease interceptors that are designed to receive the discharge of food waste.
1014.2 Hydromechanical Grease Interceptors. Plumbing fixtures or equipment connected to a Type A and B hydromechanical grease interceptor shall discharge through an approved type of vented flow control installed in a readily accessible and visible location. Flow control devices shall be
CPC § 1014.1.1 High relevance — show source text
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TRAPS AND INTERCEPTORS
1014.1.1 Trapped and Vented. Each fixture discharging into a grease interceptor shall be individually trapped and vented in an approved manner.
1014.1.2 Maintenance. Grease interceptors shall be maintained in efficient operating condition by periodic removal of the accumulated grease and latent material. No such collected grease shall be introduced into drainage piping or a public or private sewer. Where the Authority Having Jurisdiction determines that a grease interceptor is not being properly cleaned or maintained, the Authority Having Jurisdiction shall have the authority to mandate the installation of additional equipment or devices and to mandate a maintenance program.
1014.1.3 Food Waste Disposers and Dishwash- ers. No food waste disposer or dishwasher shall be connected to or discharge into a grease interceptor. Commercial food waste disposers shall be permitted to discharge directly into the building’s drainage system.
Exception: Food waste disposers shall be permitted to discharge to grease interceptors that are designed to receive the discharge of food waste.
1014.2 Hydromechanical Grease Interceptors. Plumbing fixtures or equipment connected to a Type A and B hydromechanical grease interceptor shall discharge through an approved type of vented flow control installed in a readily accessible and visible location. Flow control devices shall be
designed and installed so that the total flow through such device or devices shall at no time be greater than the rated flow of the connected grease interceptor. No flow control device having adjustable or removable parts shall be approved. The vented flow control device shall be located such that no system vent shall be between the flow control and the grease interceptor inlet. The vent or air inlet of the flow control device shall connect with the sanitary drainage vent system, as elsewhere required by this code, or shall terminate through the roof of the building, and shall not terminate to the free atmosphere inside the building.
Exception: Listed grease interceptors with integral flow controls or restricting devices shall be installed in an accessible location in accordance with the manufacturer’s installation
instructions.
1014.2.1 Capacity. The total capacity in gallons (gal) (L) of fixtures discharging into a hydromechanical grease interceptor shall not exceed two and one-half times the certified gallon per minute (gpm) (L/s) flow rate of the interceptor in accordance with Table 1014.2.1.
For this section, the term “fixture” shall mean and include each plumbing fixture, appliance, apparatus, or other equipment required to be connected to or discharged into a grease interceptor by a provision of this section.
1014.2.2 Vent. A vent shall be installed downstream of
hydromechanical grease interceptors in accordance with the requirements of this code.
TABLE 1014.2.1
HYDROMECHANICAL GREASE INTERCEPTOR SIZING USING GRAVITY FLOW RATES [1]
CPC § 10-5 High relevance — show source text
1002 Maintenance and Plans . . . . . . . . . . . . . . . . . . . . . . . . 10-5
1003 General Means of Egress . . . . . . . . . . . . . . . . . . . . . . . 10-5
1004 Occupant Load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-7
1005 Means of Egress Sizing. . . . . . . . . . . . . . . . . . . . . . . . . 10-9
1006 Number of Exits and Exit Access Doorways . . . . . 10-10
1007 Exit and Exit Access Doorway Configuration . . . . 10-14
1008 Means of Egress Illumination . . . . . . . . . . . . . . . . . . 10-14
1009 Accessible Means of Egress. . . . . . . . . . . . . . . . . . . . 10-15
1010 Doors, Gates and Turnstiles . . . . . . . . . . . . . . . . . . . 10-19
1011 Stairways . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-29
1012 Ramps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-33
1013 Exit Signs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-34
1014 Handrails. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-36
1015 Guards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-37
1016 Exit Access . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-39
1017 Exit Access Travel Distance. . . . . . . . . . . . . . . . . . . . 10-40
1018 Aisles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-41
1019 Exit Access Stairways and Ramps . . . . . . . . . . . . . . 10-42
1020 Corridors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-42
1021 Egress Balconies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-44
1022 Exits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-44
CPC § 19-1 Medium relevance — show source text
000|19-1|21-6|16-5|17-1|15-1|14-0|12-6|9-11|9-7| |24|2-#6|40,000|17-7|21-1|14-1|14-10|12-8|11-9|10-8|8-7|8-4| |24|2-#6|60,000|DR|DR|DR|DR|DR|DR|DR|DR|DR| |24|Center distance_A_k, l|Center distance_A_k, l|3-3|4-1|2-5|2-7|2-1|1-11|1-7|1-2|1-1| |For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1 pound per square foot = 0.0479 kPa, Grade 40 = 280 MPa, Grade 60 = 420 MPa.
a. See Table R608.3 for tolerances permitted from nominal thickness.
b. Table values are based on concrete with a minimum specified compressive strength of 2,500 psi. See Note j.
c. Table values are based on uniform loading. See Section R608.8.2 for lintels supporting concentrated loads.
d. Deflection criterion is_L_/240, where_L_ is the clear span of the lintel in inches, or1/2-inch, whichever is less.
e. Linear interpolation is permitted between ground snow loads and between lintel depths.
f. DR indicates design required.
g. Lintel depth,D, is permitted to include the available height of wall located directly above the lintel, provided that the increased lintel depth spans the entire length of the
lintel.
h. Stirrups shall be fabricated from reinforcing bars with the same yield strength as that used for the main longitudinal reinforcement.
i. Allowable clear span without stirrups applicable to all lintels of the same depth,D. Top and bottom reinforcement for lintels without stirrups shall be not less than the least
amount of reinforcement required for a lintel of the same depth and loading condition with stirrups. All other spans require stirrups spaced at not more than_d_/2.
j. Where concrete with a minimum specified compressive strength of 3,000 psi is used, clear spans for lintels without stirrups shall be permitted to be multiplied by 1.05. If the
increased span exceeds the allowable clear span for a lintel of the same depth and loading condition with stirrups, the top and bottom reinforcement shall be equal to or
greater than that required for a lintel of the same depth and loading condition that has an allowable clear span that is equal to or greater than that of the lintel without stir-
rups that has been increased.
k. Center distance,A, is the center portion of the clear span where stirrups are not required. This is applicable to all longitudinal bar sizes and steel yield strengths.
l. Where concrete with a minimum specified compressive strength of 3,000 psi is used, center distance,A, shall be permitted to be multiplied by 1.10.
m.The maximum clear opening width between two solid wall segments shall be 18 feet. See Section R608.7.2.1.CPC § 1009.1 Medium relevance — show source text
TABLE 1009.1 APPROVED INTERCEPTORS (CLARIFIERS)
APPLICATION STANDARD
Fats, Oil, Grease
(FOG)ASME A112.14.3, ASME A112.14.4,
ASME A112.14.6, CSA B481,
ANSI/CAN/IAPMO Z1001,
PDI G-101, PDI G-102Solid Waste IAPMO IGC 167
Non-petroleum OilASME A112.14.6, IAPMO PS 80,
PDI G-102
Petroleum OilASTM D6104, IAPMO IGC 183,
IAPMO IGC 3251009.2 Approval. The size, type, and location of each interceptor (clarifier) or separator shall be approved by the Authority Having Jurisdiction. Except where otherwise specifically permitted, no wastes other than those requiring treatment or separation shall be discharged into an interceptor (clarifier). 1009.3 Design. Interceptors (clarifiers) for sand and similar heavy solids shall be so designed and located as to be readily accessible for cleaning and shall have a water seal of not less than 6 inches (152 mm). 1009.4 Relief Vent. Interceptors (clarifiers) shall be so designed that they will not become air-bound where closed covers are used. Each interceptor (clarifier) shall be properly vented.
1009.5 Location. Each interceptor (clarifier) cover shall be readily accessible for servicing and maintaining the interceptor (clarifier) in working and operating condition. The use of ladders or the removal of bulky equipment to service interceptors (clarifiers) shall constitute a violation of accessibility. Location of interceptors (clarifiers) shall be shown on the approved building plan. 1009.6 Maintenance of Interceptors. Interceptors shall be maintained in efficient operating condition by periodic removal of accumulated grease, scum, oil, or other floating substances and solids deposited in the interceptor. 1009.7 Discharge. The waste pipe from oil and sand interceptors shall discharge as approved by the Authority Having Jurisdiction.
1010.0 Slaughterhouses, Packing Establishments, etc.
1010.1 General. A fish, fowl, and animal slaughterhouse or establishment; a fish, fowl, and meat packing or curing establishment; a soap factory, tallow-rendering, fat-rendering, and a hide-curing establishment shall be connected to and shall drain or discharge into an approved grease interceptor (clarifier).
TABLE 1009.1 APPROVED INTERCEPTORS (CLARIFIERS)
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TRAPS AND INTERCEPTORS
1010.2 Meat and Poultry Processing Plants. [AGR]
1010.2.1 Drainage and Plumbing Systems. Drainage and plumbing systems shall meet the require- ments of Section 724.0.
1010.2.1.1 Each floor drain shall be equipped with a deep-seal trap.
CPC § 3509.4 Medium relevance — show source text
Maintenance 110 Mall (see Covered Mall Building) Manifolds Cylinders 3509.4 Identification 3509.5
Piping 3509 Manual Fire Alarm Box 202, 907.4.2 Manufacture of Organic Coatings Chapter 29 Marinas 202, Chapter 36 Marine Motor Fuel-Dispensing Facility 2310, 3605 Defined 202
Fire protection 2310.6 Fueling 2310.4 General 2310.1
Nozzles 2310.3.3 Marking (see Placards; Placarding) 503.3, 909.14, 5003.5.1 Compressed gas 5303.2 Cryogenic containers 5503.4 Shaftway 316.2 Tank 5706.2.2
Warnings 5003.8.7.4 Mass Notification Systems 917 Material Safety Data Sheet (MSDS) (see Safety Data Sheet) Mattresses (in Groups I and R) 805 Maximum Allowable Quantity per Control Area 5003.1.1, Table 5003.1.1(1), Table 5003.1.1(2), Table 5003.1.1(3), Table 5003.1.1(4), 5003.11 Defined 202
Means of Appeals 112 Means of Egress Chapter 10, 1104, 3312 Accessible means of egress 1009 Assembly 1030 Bleachers 1030.1.1 Buildings under construction or demolition 3312
Corridors 1020, 1104.17 Defined 202
Egress court 202, 1029.1 Elevators, escalators and moving walks 1003.7, 1104.2 Emergency escape and rescue 1031 Existing buildings 1104 Exit access 1016 Exit discharge 1028 Exits 1006
Guards 1015, 1104.6 Handrails 1014
Illumination 1008, 1104.3 Locks, latches 1010.2.4 Maintenance of 1032
Membrane structures 3103.11 Monitoring and recording of 1010.2.9 Obscuration of 316.4, 1032.4, 1032.6
Obstructions 1032.3, 1032.3.1 Outdoor assembly events 3107.3 Ramps 1012 Signs 1013 Sizing 1005 Stairways 1023, 1027 Tents 3103.11 Mechanical Refrigeration (see Refrigeration System) Mechanical Stocking Methods 3206.10.1.1 Defined 202 Medical Care (see Institutional Occupancies) 202, 203 Medical Gas Systems 5306.5 Medical Gases 5306 Membrane Structure Chapter 31 Defined 202 Membrane-Penetration Firestop System
202
CPC § 901.0 Medium relevance — show source text
H 901.0 Commercial or Industrial Special Liquid- Waste Disposal.
H 901.1 Interceptor. Where liquid wastes contain excessive amounts of grease, garbage, flammable wastes, sand, or other ingredients that affect the operation of a private sewage disposal system, an interceptor for such wastes shall be installed.
H 901.2 Installation. Installation of such interceptors shall comply with Section 1009.0 of this code, and their location shall comply with Table H 101.8 of this appendix. H 901.3 Sampling Box. A sampling box shall be installed where required by the Authority Having Jurisdiction. H 901.4 Design and Structural Requirement. Interceptors shall be of approved design and be not less than two compartments. Structural requirements shall comply with Section H 501.0 of this appendix.
H 901.5 Location. Interceptors shall be located as close to the source as possible and be accessible for servicing. Necessary manholes for servicing shall be at grade level and be gastight.
H 901.6 Waste Discharge. Waste discharge from interceptors shall be permitted to be connected to a septic tank or other primary system or be disposed into a separate disposal system. H 901.7 Design Criteria. A formula shall be permitted to be adapted to other types of occupancies with similar wastes. (See Chart H 901.7)
H 1001.0 Inspection and Testing. H 1001.1 Inspection. Inspection requirements shall comply with the following:
(1) Applicable provisions of Section 105.0 of this code and this appendix shall be required. Plans shall be required in accordance with Section 103.3 of this code.
(2) System components shall be properly identified as to manufacturer. Septic tanks or other primary systems shall have the rated capacity permanently marked on the unit.
(3) Septic tanks or other primary systems shall be installed on dry, level, well-compacted soil.
(4) Where design is predicated on soil tests, the system shall be installed at the same location and depth as the tested
area.
H 1001.2 Testing. Testing requirements shall comply with the following:
(1) Septic tanks or other primary components shall be filled with water to flow line before requesting an inspection. Seams or joints shall be left exposed (except the bottom), and the tank shall remain watertight.
(2) A flow test shall be performed through the system to the point of effluent disposal. All lines and components shall
CHART H 901.7
RECOMMENDED DESIGN CRITERIA
GREASE AND GARBAGE, COMMERCIAL KITCHENS Number of meals per peak hour x Waste flow rate [1] x Retention time [2] x Storage factor [3] = (Interceptor size liquid capacity)
SAND-SILT OIL, AUTO WASHERS vehicles Number of per hour x Waste flow rate [1] x Retention time [2] x Storage factor [3] = (Interceptor size liquid capacity)
SILT-LINT GREASE, LAUNDRIES, LAUNDROMATS
Number of x 2 cycles per x Waste flow x Retention time [2] = Storage factor [3] = Interceptor size machines hour rate [1] (liquid capacity)
Notes: 1 For waste flow rate see Table H 201.1(4). 2 Retention Times:
CPC § 1010.5.2 Medium relevance — show source text
1010.5.2 Sewage and Plant Waste. The sewer sys- tem have adequate slope and capacity to remove readily all waste from the various processing operations and to minimize, or if possible, prevent stoppage and surcharg- ing of the system. When the sewage disposal system is a private system which is required to be approved by a state or local health authority, the applicant shall fur- nish the administrator a letter from the proper health authority indicating that the sewage disposal system is acceptable to such authority.
1011.0 Minimum Requirements for Auto Wash Racks.
1011.1 General. A private or public wash rack or floor or slab used for cleaning machinery or machine parts shall be adequately protected against storm or surface water and shall drain or discharge into an approved interceptor (clarifier).
1012.0 Commercial and Industrial Laundries.
1012.1 General. Laundry equipment in commercial and industrial buildings that do not have integral strainers shall discharge into an interceptor having a wire basket or similar device that is removable for cleaning and that will prevent passage into the drainage system of solids [1] ⁄ 2 of an inch (12.7 mm) or larger in maximum dimensions, such as string, rags, buttons, or other solid materials detrimental to the public sewerage system.
1013.0 Bottling Establishments.
1013.1 General. Bottling plants shall discharge their process wastes into an interceptor that will provide for the separation of broken glass or other solids, before discharging liquid wastes into the drainage system.
1014.0 Grease Interceptors.
1014.1 General. Where it is determined by the Authority Having Jurisdiction that waste pretreatment is required, an approved type of grease interceptor(s) shall comply with ASME A112.14.3, ASME A112.14.4, CSA B481, ANSI/CAN/IAPMO Z1001, PDI G-101, or PDI G-102, and sized in accordance with Section 1014.2.1 or Section
1014.3.6, shall be installed in accordance with the manufacturer’s installation instructions to receive the drainage from fixtures or equipment that produce grease-laden waste. Grease-laden waste fixtures shall include, but not be limited to, sinks and drains, such as floor drains, floor sinks, and other fixtures or equipment in serving establishments, such as restaurants, cafes, lunch counters, cafeterias, bars and clubs, hotels, hospitals, sanitariums, factory or school kitchens, or other establishments where grease is introduced into the drainage or sewage system in quantities that can effect line stoppage or hinder sewage treatment or private sewage disposal systems. A combination of hydromechanical, gravity grease interceptors and engineered systems shall be allowed to meet this code and other applicable requirements of the Authority Having Jurisdiction where space or existing physical constraints of existing buildings necessitate such installations. A grease interceptor shall not be required for individual dwelling units or private living quarters. Water closets, urinals, and other plumbing fixtures conveying human waste shall not drain into or through the grease interceptor.
1014.1A [OSHPD 1, 1R, 2, 3, 4 & 5] The Authority Having Jurisdiction is the individual official, board, department or agency authorized to administer and enforce the sewage treatment system in the area of the location of the health facil- ity.
CPC § 2304.10.6 Medium relevance — show source text
Fastenings 2304.10.6 Quality 2303.1.9 Required 2304.12 Shakes, roof covering 1507.9.6, 1507.9.8 Private Garage 406.3, 1010.1.2, 1502.3 Accessibility Chapters 11A and 11B Projection Rooms Motion picture 409 Projections, Combustible 705.2.3, 705.2.3.1 Property Line (see Fire Separation Distance)
705.3 Property Maintenance 101.4.4 Proscenium
Curtain 410.2.5
Wall 410.2.4 Psychiatric Hospitals
[see Institutional (see Group I-2)] 308.4 Public Address System (see Emergency Communications) Covered and open mall buildings 402.7, 907.2.20, 2702.2 Special amusement areas 411.3 Public Property Chapter 32, Chapter 33 Public Right-Of-Way Encroachments Chapter 32 Puzzle Room 411 Pyrophoric Materials Table 307.1(1), 307.4
Railing (see Guards And Handrails) Raised-deck System 1511.9 Ramps 1012 Assembly occupancy 1030.14 Construction 1012.2, 1012.5.3, 1012.7,
1012.10
Exit 1023
Exit access 1019
Exterior 1027
Guards 1012.9, 1015, 1607.9 Handrails 1012.8, 1014, 1607.9 Interior 1012.2 Landings 1012.6 Parking garage 406.4.3 Slope 1012.2 Recreational Facilities Accessibility Chapter 11B Amusement rides Chapter 11B Play structure 402.6.3, 424 Special amusement areas (see Amusement Areas, Special) Referenced Standards Chapter 35 Applicability 102.3, 102.4 Fire resistance 703.2
List Chapter 35 Organizations Chapter 35 Reformatories
[see Institutional (Group I-3)] 308.4 Refrigeration (see Mechanical) 101.4.2 Machinery room 1006.2.2.2
Refuge Areas (see Horizontal Exit, Smoke Compartments, Storm Shelters) 407.5.3, 408.6.2, 420.6.1, 422.3.2, 423, 423.3, 423.4, 1026.4 Refuse Chute 713.13
Reinforcement
CPC § 3.785 Medium relevance — show source text
3.785 L
1014.3 Gravity Grease Interceptors. Required gravity grease interceptors shall comply with the provisions of Section 1014.3.1 through Section 1014.3.7.
1014.3.1 General. The provisions of this section shall apply to the design, construction, installation, and testing of commercial kitchen gravity grease interceptors.
1014.3.2 Waste Discharge Requirements. Waste discharge in establishments from fixtures and equipment
For SI units: 1 inch = 25.4 mm, 1 gallon per minute = 0.06 L/s, 1 gallon =
3.785 L
198 2025 CALIFORNIA PLUMBING CODE
), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.
TRAPS AND INTERCEPTORS
which contain grease, including but not limited to, scullery sinks, pot and pan sinks, dishwashers, soup kettles, and floor drains located in areas where grease-containing materials exist, shall be permitted to be drained into the sanitary waste through the interceptor where approved by the Authority Having Jurisdiction.
1014.3.2.1 Toilets and Urinals. Toilets, urinals, and other similar fixtures shall not drain through the interceptor.
1014.3.2.2 Inlet Pipe. Waste shall enter the interceptor through the inlet pipe.
1014.3.3 Design. Gravity interceptors shall be constructed in accordance with the applicable standard in Chapter 17 or the design approved by the Authority Having Jurisdiction.
1014.3.4 Location. Each grease interceptor shall be so installed and connected that it shall be easily accessible for inspection, cleaning, and removal of the intercepted grease. A gravity grease interceptor that complies with ANSI/CAN/IAPMO Z1001 shall not be installed in a
building where food is handled. Location of the grease interceptor shall meet the approval of the Authority Having Jurisdiction.
1014.3.4.1 Interceptors. Interceptors shall be placed as close as practical to the fixtures they serve.
1014.3.4.2 Business Establishment. Each
business establishment for which a gravity grease interceptor is required shall have an interceptor which shall serve that establishment unless other wise approved by the Authority Having Jurisdiction.
1014.3.4.3 Access. Each gravity grease interceptor shall be located to be readily accessible to the equipment required for maintenance.
1014.3.5 Construction Requirements. Gravity grease interceptors shall be designed to remove grease from effluent and shall be sized in accordance with this
section. Gravity grease interceptors shall also be designed to retain grease until accumulations can be removed by pumping the interceptor. When provided, a sample box shall be located at the outlet end of gravity grease interceptors so that the Authority Having Jurisdiction can periodically sample effluent quality.
1014.3.6 Sizing Criteria. The volume of the interceptor shall be determined by using Table 1014.3.6. Where drainage fixture units (DFUs) are not known, the interceptor shall be sized based on the maximum DFUs allowed for the pipe size connected to the inlet of the interceptor. Refer to Table 703.2, Drainage Piping, Horizontal.
CPC § 1014.3.4 Medium relevance — show source text
1014.3.4 Location. Each grease interceptor shall be so installed and connected that it shall be easily accessible for inspection, cleaning, and removal of the intercepted grease. A gravity grease interceptor that complies with ANSI/CAN/IAPMO Z1001 shall not be installed in a
building where food is handled. Location of the grease interceptor shall meet the approval of the Authority Having Jurisdiction.
1014.3.4.1 Interceptors. Interceptors shall be placed as close as practical to the fixtures they serve.
1014.3.4.2 Business Establishment. Each
business establishment for which a gravity grease interceptor is required shall have an interceptor which shall serve that establishment unless other wise approved by the Authority Having Jurisdiction.
1014.3.4.3 Access. Each gravity grease interceptor shall be located to be readily accessible to the equipment required for maintenance.
1014.3.5 Construction Requirements. Gravity grease interceptors shall be designed to remove grease from effluent and shall be sized in accordance with this
section. Gravity grease interceptors shall also be designed to retain grease until accumulations can be removed by pumping the interceptor. When provided, a sample box shall be located at the outlet end of gravity grease interceptors so that the Authority Having Jurisdiction can periodically sample effluent quality.
1014.3.6 Sizing Criteria. The volume of the interceptor shall be determined by using Table 1014.3.6. Where drainage fixture units (DFUs) are not known, the interceptor shall be sized based on the maximum DFUs allowed for the pipe size connected to the inlet of the interceptor. Refer to Table 703.2, Drainage Piping, Horizontal.
1014.3.7 Abandoned Gravity Grease Intercep- tors. Abandoned grease interceptors shall be pumped and filled as required for abandoned sewers and sewage disposal facilities in Section 722.0.
DRAINAGE FIXTURE UNITS1, 3
(DFUs)INTERCEPTOR VOLUME2
(gallons)
8500
21750
351000
901250 172 1500
2162000
3072500
3423000
4284000
5765000
7207500 2112 10 000
264015 000 For SI units: 1 gallon = 3.785 L
Notes: 1 The maximum allowable DFUs plumbed to the kitchen drain lines that will be connected to the grease interceptor. 2 This size is based on DFUs, the pipe size from this code; Table 703.2; Useful Tables for flow in half-full pipes (ref: Mohinder Nayyar Piping Handbook, 3rd Edition, 1992). Based on 30-minute retention time (ref.: George Tchobanoglous and Metcalf & Eddy. Wastewater Engineering Treatment, Disposal, and Reuse, 3rd Ed. 1991 & Ronald Crites and George Tchobanoglous. Small and Decentralized Wastewater Management Systems, 1998). Rounded up to nominal interceptor volume.
CPC § 2-2 Medium relevance — show source text
36**| |** HEADERS AND GIRDERS SUPPORTING**|** SIZE**|** Spane**|** NJd**|** Spane**|** NJd**|** Spane**|** NJd**| |Two floors|2-2 × 4|2-7|1|1-11|1|1-7|1| |Two floors|2-2 × 6|3-11|1|2-11|2|2-5|2| |Two floors|2-2 × 8|5-0|1|3-8|2|3-1|2| |Two floors|2-2 × 10|5-11|2|4-4|2|3-7|2| |Two floors|2-2 × 12|6-11|2|5-2|2|4-3|3| |Two floors|3-2 × 8|6-3|1|4-7|2|3-10|2| |Two floors|3-2 × 10|7-5|1|5-6|2|4-6|2| |Two floors|3-2 × 12|8-8|2|6-5|2|5-4|2| |Two floors|4-2 × 8|7-2|1|5-4|1|4-5|2| |Two floors|4-2 × 10|8-6|1|6-4|2|5-3|2| |Two floors|4-2 × 12|10-1|1|7-5|2|6-2|2| |For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm.
a. Spans are given in feet and inches.
b. Spans are based on minimum design properties for No. 2 grade lumber of Douglas fir-larch, hem-fir, Southern pine, and spruce-pine-fir.
c. Building width is measured perpendicular to the ridge. For widths between those shown, spans are permitted to be interpolated.
d. NJ = Number of jack studs required to support each end. Where the number of required jack studs equals one, the header is permitted to be supported by an_approved_ fram-
ing anchor attached to the full-height wall stud and to the header.
e. Spans are calculated assuming the top of the header or girder is laterally braced by perpendicular framing. Where the top of the header or girder is not laterally braced (for
example, cripple studs bearing on the header), tabulated spans for headers consisting of 2 × 8, 2 × 10, or 2 × 12 sizes shall be multiplied by 0.70 or the header or girder shall be
designed.|For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm.
a. Spans are given in feet and inches.
b. Spans are based on minimum design properties for No. 2 grade lumber of Douglas fir-larch, hem-fir, Southern pine, and spruce-pine-fir.
c. Building width is measured perpendicular to the ridge. For widths between those shown, spans are permitted to be interpolated.
d. NJ = Number of jack studs required to support each end. Where the number of required jack studs equals one, the header is permitted to be supported by an_approved_ fram-
ing anchor attached to the full-height wall stud and to the header.
e.
Frequently asked questions
Who decides whether an interceptor is required?
The Authority Having Jurisdiction (AHJ) determines whether waste pretreatment is required and thus whether a grease interceptor must be installed (see §1014.1) .
How often must the interceptor be cleaned?
The CPC requires periodic removal of accumulated grease but does not specify a fixed interval; the AHJ may require a specific maintenance program or schedule if cleaning is inadequate (§1014.1.2) .
Can a dishwasher or disposer go into the grease interceptor?
Generally no — dishwashers and ordinary food waste disposers shall not discharge into a grease interceptor unless the interceptor is specifically designed to receive food‑waste discharge (see §1014.1.3) .
Are homes required to have grease interceptors?
No — individual dwelling units / private living quarters are exempt from the grease interceptor requirement under §1014.1 .
What if the interceptor isn't being maintained?
If the AHJ determines the interceptor is not being properly cleaned or maintained, the AHJ may mandate additional equipment and require a formal maintenance program (§1014.1.2) .
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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