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Appendix L — SUSTAINABLE PRACTICES

California Plumbing Code (Title 24, Part 5) · 2022 edition · updated 2026-09-10 · California

Italicized text is a California amendment to the model code, as printed in the official publication.

(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.)

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SFM HCD DSA OSHPD BSCC DPH AGR DWR CEC CA SL SLC
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SFM 1 2 1-AC **AC ** SS SS/CC 1 1R 2 3 4 5 5 5 5 5 5 5 5 5
Adopt Entire Chapter
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amended (amended sections
listed below)
Adopt only those sections
that are listed below
Chapter/Section

This state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.0.

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SUSTAINABLE PRACTICES

The provisions contained in this appendix are not mandatory unless specifically adopted by a state agency, or referenced in the adopting ordinance.

L 101.0 General. L 101.1 Applicability. The purpose of this appendix is to provide a comprehensive set of technically sound provisions that encourage sustainable practices and works towards enhancing the design and construction of plumbing systems that result in a positive long-term environmental impact. This appendix is not intended to circumvent the health, safety, and general welfare requirements of this code. L 101.2 Definition of Terms. For the purposes of this code, the definitions in Section L 201.0 shall apply to this appendix.

No attempt is made to define ordinary words, which are used in accordance with their established dictionary meanings, except where a word has been used loosely, and it is necessary to define its meaning as used in this appendix to avoid misunderstanding.

The definitions of terms are arranged alphabetically according to the first word of the term.

L 201.0 Definitions. Catch Can Test. Method to measure the precipitation rate of an irrigation system by placing catchment containers at various random positions in the irrigation zone for a prescribed amount of time during irrigation application. The volumes of water in the containers are measured, averaged, and calculated to determine precipitation rate. Tests are conducted using irrigation industry accepted practices. Combination Ovens. A device that combines the function of hot air convection (oven mode) and saturated and superheated steam heating (steam mode), or both, to perform steaming, baking, roasting, rethermalizing, and proofing of various food products. In general, the term combination oven is used to describe this type of equipment, which is self-contained. The combination oven is also referred to as a combination oven/steamer, combi or combo. Energy Star. A joint program of the U.S. Environmental Protection Agency and the U.S. Department of Energy. Energy Star is a voluntary program designed to identify and promote energy-efficient products and practices. Evapotranspiration (ET). The water transpired from vegetation, evaporated from the soil, water, and plant surfaces. Evapotranspiration rates are values expressed in inches (mm) per unit of time (day, week, month, or year). Evapotranspiration rates vary by components of weather conditions, including insolation, humidity, temperatures and wind, and time of year. Food Steamers (Steam Cookers). A cooking appliance wherein heat is imparted to food in a closed compartment by direct contact with steam. The compartment can be at or above atmospheric pressure. The steam can be static or circulated. Gang Showers. Shower compartments designed and intended for use by multiple persons simultaneously.

lation, humidity, temperatures and wind, and time of year. Food Steamers (Steam Cookers). A cooking appliance wherein heat is imparted to food in a closed compartment by direct contact with steam. The compartment can be at or above atmospheric pressure. The steam can be static or circulated. Gang Showers. Shower compartments designed and intended for use by multiple persons simultaneously.

Hydrozone. A grouping of plants with similar water requirements that are irrigated by the same irrigation zone. Irrigation Control System. An irrigation control system consists of a combination of a programmable controller using one or more inputs or sensors that, in combination, estimate or measure the availability of moisture for plants in order to operate an irrigation system, in such a manner that the system replenishes water as needed while minimizing excess water use. A properly programmed irrigation control system requires initial site specific set-up and will make irrigation schedule adjustments, including run times and required cycles throughout the irrigation season without human intervention. Irrigation Demand. The amount of water not supplied by natural precipitation that is needed to maintain landscape plant life in good condition. Irrigation demand is calculated by subtracting natural effective precipitation from the ET rate adjusted by the landscape coefficient, which includes the functional purpose and desired quality of the plant being irrigated. Irrigation Emission Device. The various landscape irrigation equipment terminal fittings or outlets that emit water for irrigating vegetation in a landscape. Irrigation Zone. The landscape area that is irrigated by a set of landscape irrigation emission devices installed on the same water supply line downstream of a single valve. Kitchen and Bar Sink Faucets. A faucet that discharges into a kitchen or bar sinks in domestic or commercial installations. Supply fittings that discharge into other type sinks, including clinical sinks, floor sinks, service sinks and laundry trays are not included. Lavatory. (1) A basin or vessel for washing. (2) A plumbing fixture, as defined in (1), especially placed for use in personal hygiene. Principally not used for laundry purposes and never used for food preparation, or utensils, in food services. (3) A fixture designed for the washing of the hands and face. Sometimes called a wash basin. Lavatory Faucet. A faucet that discharges into a lavatory basin in a domestic or commercial installation. Low Application Rate Irrigation. A means of irrigation using low precipitation rate sprinkler heads or low flow emitters in conjunction with cycling irrigation schedules to apply water at a rate less than the soil absorption rate. Low Flow Emitter. Low-flow irrigation emission device designed to dissipate water pressure and discharge a small uniform flow or trickle of water at a constant flow rate. To be classified as a low flow emitter: drip emitters shall discharge water at less than 4 gallons (15 L) per hour per emitter; microspray, micro-jet, and misters shall discharge water at a maximum of 30 gallons (114 L) per hour per nozzle. Low Precipitation Rate Sprinkler Heads. Landscape irrigation emission devices or sprinkler heads with a maxi

w or trickle of water at a constant flow rate. To be classified as a low flow emitter: drip emitters shall discharge water at less than 4 gallons (15 L) per hour per emitter; microspray, micro-jet, and misters shall discharge water at a maximum of 30 gallons (114 L) per hour per nozzle. Low Precipitation Rate Sprinkler Heads. Landscape irrigation emission devices or sprinkler heads with a maxi

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mum precipitation rate of 1 inch per hour (25.4 mm/h) over the applied irrigation area. Maintenance. The upkeep of property or equipment by the owner of the property in compliance with the requirements of this appendix. Metering Faucet. A self-closing faucet that dispenses a specific volume of water for each actuation cycle. The volume or cycle duration can be fixed or adjustable. Modified Evapotranspiration. Numeric values, expressed in inches/hour (in/h), of evapotranspiration rates, derived by altering ETo rates by applying factors of specific needs of the vegetation and local climate conditions. Modified evapotranspiration rates are used as a factor in estimating the irrigation water needs of landscapes. Common usage includes reference evapotranspiration as the base rate, modified by coefficients or factors for specific plant types and densities. Multi-Occupant Spaces. Indoor spaces used for presentations and training, including classrooms and conference rooms. Precipitation Rate. The sprinkler head application rate of water applied to landscape irrigation zone, measured as inches per hour (mm/h). Precipitation rates of sprinkler heads are calculated according to the flow rate, pattern, and spacing of the sprinkler heads. Pre-Rinse Spray Valve. A handheld device for use with commercial dishwashing and ware washing equipment that sprays water on dishes, flatware, and other food service items for the purpose of removing food residue before cleaning and sanitizing the items. Recirculation System. A system of hot water supply and return piping with shutoff valves, balancing valves, circulating pumps, and a method of controlling the circulating system. Reference Evapotranspiration (ETo). Numeric value, expressed in inches/hour (in/h), calculated as the water necessary to produce maximum biomass based upon a cool-season turf grass 4 inches to 6 inches (102 mm to 152 mm) tall. Common sources for obtaining local reference evapotranspiration rates are local agriculture extension services, state departments of agriculture, water agencies, irrigation professionals, the United States Geological Survey, and internet websites. Reverse Osmosis Reject Water. Water that does not pass through a membrane of a reverse osmosis system. Run Out. The developed length of pipe that extends away from the circulating loop system to a fixture(s). Self Closing Faucet. A faucet that closes itself after the actuation or control mechanism is deactivated. The actuation or control mechanism can be mechanical or electronic. Single Occupant Spaces. Private offices, workstations in open offices, reception workstations, and ticket booths. Soil Absorption Rate. The rate of the soil’s ability to allow water to percolate or infiltrate the soil and be retained in the root zone of the soil expressed as inches per hour (mm/h). Sprinkler Head. Landscape irrigation emission device discharging water in the form of sprays or rotating streams, not including low flow emitters. Storage Tank. The central component of the rainwater, stormwater, or dry weather runoff catchment system. Also known as a cistern or rain barrel.

filtrate the soil and be retained in the root zone of the soil expressed as inches per hour (mm/h). Sprinkler Head. Landscape irrigation emission device discharging water in the form of sprays or rotating streams, not including low flow emitters. Storage Tank. The central component of the rainwater, stormwater, or dry weather runoff catchment system. Also known as a cistern or rain barrel.

Stormwater. Natural precipitation that has contacted a surface at grade or below grade and has not been put to beneficial use. Stormwater Catchment System. A system that collects and stores stormwater for beneficial use. Submeter. A meter installed subordinate to a site meter. Also known as a dedicated meter. WaterSense. A voluntary program of the U.S., Environmental Protection Agency, designed to identify and promote water-efficient products and practices. Water Closet. A fixture with a water-containing receptor that receives liquid and solid body waste and on actuation conveys the waste through an exposed integral trap into a drainage system. Also referred to as a toilet. Water Factor (WF). A measurement and rating of appliance water efficiency, most often used for residential and light commercial clothes washers, as follows:

Water Factor (WF), Clothes Washer. The quantity of water in gallons used to complete a full wash and rinse cycle per measured cubic foot capacity of the clothes container.

L 301.0 General Regulations. L 301.1 Installation. Plumbing systems covered by this appendix shall be installed in accordance with this code, other applicable codes, and the manufacturer’s installation instructions. L 301.2 Qualifications. Where permits are required, the Authority Having Jurisdiction shall have the authority to require contractors, installers, or service technicians to demonstrate competency. Where determined by the Authority Having Jurisdiction, the contractor, installer or service technician shall be licensed to perform such work.

L 302.0 Disposal of Liquid Waste. L 302.1 Disposal. It shall be unlawful for a person to cause, suffer, or permit the disposal of sewage, human excrement, or other liquid wastes, in a place or manner, except through and by means of an approved drainage system, installed and maintained in accordance with the provisions of this code. L 302.2 Connections to Plumbing System Required. Equipment and appliances, used to receive or discharge liquid wastes or sewage, shall be connected properly to the drainage system of the building or premises, in accordance with the requirements of this code.

L 303.0 Abandonment. L 303.1 General. An abandoned system or part thereof covered under the scope of this appendix shall be disconnected from remaining systems, drained, plugged, and capped in an approved manner.

L 401.0 Water Conservation and Efficiency. L 401.1 Scope. The provisions of this section establish the means of conserving potable and nonpotable water used in and around a building.

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L 402.0 Water-Conserving Plumbing Fixtures and Fittings. L 402.1 General. The maximum water consumption of fixtures and fixture fittings shall comply with the flow rates specified in Table L 402.1, and Section L 402.2 through Section L 402.10.

TABLE L 402.1 MAXIMUM FIXTURE AND FIXTURE FITTINGS FLOW RATES

FIXTURE TYPE FLOW RATE


Showerheads
2.0 gpm at 80 psi1


Kitchen faucets residential4
1.8 gpm at 60 psi

Lavatory faucets residential
1.5 gpm at 60 psi


Lavatory faucets other than
residential
0.5 gpm at 60 psi


Metering faucets
0.25 gallons/cycle


Metering faucets for wash
fountains
One 0.25 gallons/cycle fixture fit-
ting for each 20 inches rim space


Wash fountains
One 2.2 gpm at 60 psi fixture fit-
ting for each 20 inches rim space


Water Closets
1.28 gallons/flush2


Urinals
0.5 gallons/flush3



Commercial Pre-Rinse
Spray Valves
1.3 gpm at 60 psi

For SI units: 1 gallon per minute = 0.06 L/s, 1 pound-force per square inch = 6.8947 kPa, 1 inch = 25.4 mm, 1 gallon = 3.785 L Notes: 1 For multiple showerheads serving one shower compartment see Section L 402.6.1. 2 Shall be listed to EPA WaterSense Tank-Type Toilet Specification. 3 Shall be listed to EPA WaterSense Flushing Urinal Specification. Nonwater urinals shall comply with specifications listed in Section L 402.3.1. 4 See Section L 402.4.

L 402.2 Water Closets. No water closet shall have an effective flush volume exceeding 1.28 gallons per flush (gpf) (4.8 Lpf).

L 402.2.1 Gravity, Pressure Assisted, and Elec- tro-Hydraulic Tank Type Water Closets. Gravity, pressure assisted, and electro-hydraulic tank-type water closets shall have a maximum effective flush volume of not more than 1.28 gallons (4.8 Lpf) of water per flush in accordance with ASME A112.19.2/CSA B45.1 or ASME A112.19.14 and shall be listed to the EPA WaterSense Specification for Tank-Type Toilets. The effective flush volume for dual flush toilets is defined as the composite, average flush volume of two reduced flushes and one full flush. L 402.2.2 Flushometer-Valve Activated Water Closets. Flushometer-valve activated water closets shall have a maximum flush volume of not more than 1.28 gallons (4.8 Lpf) of water per flush in accordance with ASME A112.19.2/CSA B45.1 and shall be listed to the EPA WaterSense Specification for FlushometerValve Water Closets. L 402.3 Urinals. Urinals shall have a maximum flush volume of not more than 0.5 gallon (1.9 Lpf) of water per flush in accordance with ASME A112.19.2/CSA B45.1 or CSA

APPENDIX L

B45.5/IAPMO Z124. Flushing urinals shall be listed to the EPA WaterSense Flushing Urinal Specification.

L 402.3.1 Nonwater Urinals. Nonwater urinals shall comply with ASME A112.19.3/CSA B45.4, ASME A112.19.19, or CSA B45.5/IAPMO Z124. Nonwater urinals shall be cleaned and maintained in accordance with the manufacturer’s instructions after installation. Where nonwater urinals are installed, they shall have a water distribution line roughed-in to the urinal location at a height not less than 56 inches (1422 mm) to allow for the installation of an approved backflow prevention device in the event of a retrofit. Such water distribution lines shall be installed with shutoff valves located as close as possible to the distributing main to prevent the creation of dead ends. Where nonwater urinals are installed, not less than one water supplied fixture rated at not less than 1 drainage fixture unit (DFU) shall be installed upstream on the same drain line to facilitate drain line flow and rinsing. L 402.4 Residential Kitchen Faucets. The maximum flow rate of residential kitchen faucets shall not exceed 1.8 gallons per minute (gpm) (6.8 L/m) at 60 pounds-force per square inch (psi) (414 kPa). Kitchen faucets are permitted to temporarily increase the flow above the maximum rate, but not to exceed 2.2 gpm (8.3 L/m) at 60 psi (414 kPa), and shall revert to a maximum flow rate of 1.8 gpm (6.8 L/m) at 60 psi (414 kPa) upon valve closure. L 402.5 Lavatory Faucets. The maximum water flow rate of faucets shall comply with Section L 402.5.1 and Section L 402.5.2.

L 402.5.1 Lavatory Faucets in Residences, Apartments, and Private Bathrooms in Lodging Facilities, Hospitals, and Patient Care Facilities. The flow rate for lavatory faucets installed in residences, apartments, and private bathrooms in lodging, hospitals, and patient care facilities (including skilled nursing and long-term care facilities) shall not exceed 1.5 gpm (5.7 L/m) at 60 psi (414 kPa) in accordance with ASME A112.18.1/CSA B125.1 and shall be listed to the EPA WaterSense High Efficiency Lavatory Faucet Specification.

L 402.5.2 Lavatory Faucets in Other Than Resi- dences, Apartments, and Private Bathrooms in Lodging Facilities. Lavatory faucets installed in bathrooms of buildings or occupancies other than those specified in Section L 402.5.1 shall be in accordance with Section L 402.5.2(1) or Section L 402.5.2(2). (1) The flow rate shall not exceed 0.5 gpm (1.9 L/m) at

60 psi (414 kPa) in accordance with ASME A112.18.1/CSA B125.1. (2) Metering faucets shall deliver not more than 0.25

gallons (0.95 L) of water per cycle. L 402.6 Showerheads. Showerheads shall not exceed 2.0 gpm (7.6 L/m) at 80 psi (552 kPa), and shall be listed to ASME A112.18.1/CSA B125.1 and the EPA WaterSense Specification for Showerheads.

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L 402.6.1 Multiple Showerheads Serving One Shower Compartment. The total allowable flow rate of water from multiple showerheads flowing at a given time, with or without a diverter, including rain systems, waterfalls, bodysprays, and jets, shall not exceed 2.0 gpm (7.6 L/m) per shower compartment, where the floor area of the shower compartment is less than 1800 square inches (1.161 m 2 ). For each increment of 1800 square inches (1.161 m 2 ) of floor area after that or part thereof, additional showerheads are allowed, provided the total flow rate of water from flowing devices shall not exceed 2.0 gpm (7.6 L/m) for each such increment. Exceptions: (1) Gang showers in nonresidential occupancies. Sin gular showerheads or multiple shower outlets serving one showering position in gang showers shall not have more than 2.0 gpm (7.6 L/m) total flow. (2) Where provided, shower compartments required for

persons with disabilities in accordance with Chapter 17 shall not have more than 4.0 gpm (15 L/m) total flow, where one outlet is the hand shower. L 402.6.2 Bath and Shower Diverters. The rate of leakage out of the tub spout of bath and shower diverters while operating in the shower mode shall not exceed 0.1 gpm (0.4 L/m) in accordance with ASME A112.18.1/CSA B125.1. L 402.6.3 Shower Valves. Shower valves shall comply with the temperature control performance requirements of ASSE 1016 or ASME A112.18.1/CSA B125.1 where tested at 2.0 gpm (7.6 L/m). L 402.7 Recirculating Shower Systems. Recirculating shower systems shall comply with IAPMO IGC 330. L 402.8 Commercial Pre-Rinse Spray Valves. The flow rate for a pre-rinse spray valve installed in a commercial kitchen to remove food waste from cookware and dishes before cleaning shall not be more than 1.28 gpm (4.8 L/m) at 60 psi (414 kPa). Where pre-rinse spray valves with maximum flow rates of 1.0 gpm (3.8 L/m) or less are installed, the static pressure shall be not less than 30 psi (207 kPa). Commercial kitchen pre-rinse spray valves shall be equipped with an integral automatic shutoff. Pre-rinse spray valves shall be listed to the EPA WaterSense Commercial Pre-rinse Spray Valve Specification. L 402.9 Emergency Safety Showers and Eye Wash Stations. Emergency safety showers and emergency eyewash stations shall not be limited to their water supply flow rates. L 402.10 Drinking Fountains. Drinking fountains shall be self-closing.

L 403.0 Appliances. L 403.1 Dishwashers. Residential and commercial dishwashers shall comply with the Energy Star program requirements. L 403.2 Clothes Washers. Residential clothes washers shall comply with the Energy Star program requirements. Commercial clothes washers shall comply with Energy Star program requirements, where such requirements exist.

L 404.0 Occupancy Specific Water Efficiency Requirements. L 404.1 Commercial Food Service. Commercial food service facilities shall comply with the water efficiency requirements in Section L 404.2 through Section L 404.7.5. L 404.2 Ice Makers. Ice makers shall be air cooled and shall be in accordance with Energy Star for commercial ice machines. L 404.3 Food Steamers. Boilerless type steamers shall consume not more than 2.0 gallons (7.6 L) per compartment. Boiler type steamers shall not consume more than 1.5 gallons (5.7 L) per pan per hour. L 404.4 Combination Ovens. Combination ovens shall not use water in the convection mode except when utilizing a moisture nozzle for food products in the oven. The total amount of water used by the moisture nozzle in the convection mode shall not exceed a half a gallon per hour per oven cavity. When operating in the steamer mode, combination ovens shall not consume more than 1.5 gallons per hour (gph) (5.7 L/h) per pan. L 404.5 Grease Interceptors. Grease interceptor maintenance procedures shall not include post-pumping/cleaning refill using potable water. Refill shall be by connected appliance accumulated discharge only. L 404.6 Dipper Well Faucets. Where dipper wells are installed, the water supply to a dipper well shall have a shutoff valve and flow control. The flow of water into a dipper well shall be limited by not less than one of the following methods: (1) Water flow shall not exceed the water capacity of the dip per well in one minute at a supply pressure of 60 psi (414 kPa), and the maximum flow shall not exceed 2.2 gpm (8.3 L/m) at a supply pressure of 60 psi (414 kPa). The water capacity of a dipper well shall be the maximum amount of water that the fixture can hold before water flows into the drain. (2) The volume of water dispensed into a dipper well in each

activation cycle of a self-closing fixture fitting shall not exceed the water capacity of the dipper well, and the maximum flow shall not exceed 2.2 gpm (8.3 L/m) at a supply pressure of 60 psi (414 kPa). L 404.7 Food Waste Devices. Where installed, food waste devices shall be in accordance with Section L 404.7.1 through Section L 404.7.5.

L 404.7.1 Pulpers and Mechanical Strainers. The water use for pulpers or mechanical strainers shall not exceed 3 gpm (11.4 L/m). A flow restrictor shall be installed on the water supply to limit the water flow. L 404.7.2 Food Waste Disposers. The water use for the food waste grinder shall not exceed 8 gpm (30.3 L/m) under full load condition and 1 gpm (3.8 L/m) under noload condition. Flow restrictors shall be installed on the water supply to limit the water flow rate to a maximum of 8 gpm (30.3 L/m). A load sensing device shall be installed to monitor current demand and regulate water flow.

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(3) The water supply to each building on a property with

multiple buildings where the water consumption exceeds 500 gals/d (0.021 L/s). (4) The water supply to an individual tenant space on a prop erty where one or more of the following applies: (a) Water consumption exceeds 500 gals/d (0.021 L/s)

for that tenant. (b) Tenant space is occupied by a commercial laundry,

cleaning operation, restaurant, food service, medical office, dental office, laboratory, beauty salon, or barbershop. (c) Total building area exceeds 50 000 square feet (4645

m 2 ). (5) The makeup water supplies to a swimming pool. L 407.2 Approval. Dedicated meters, other than water utility meters shall be approved by the Authority Having Jurisdiction for the intended use. L 407.3 Consumption Data. A means of communicating water consumption data from submeters to the water consumer shall be provided. L 407.4 Access. Meters and submeters shall be accessible.

L 408.0 Condensate Recovery. L 408.1 General. Condensate is permitted to be used as onsite treated nonpotable water when collected, stored, and treated in accordance with Section 1506.0.

L 408.1.1 Condensate Drainage Recovery. Condensate from air-conditioning, boiler and steam systems used to supply water for non-potable water systems shall be in accordance with Section 1506.0.

L 409.0 Water-Powered Sump Pumps. L 409.1 General. Sump pumps powered by potable or reclaimed (recycled) water pressure shall be used as an emergency backup pump. The water-powered pump shall be equipped with a battery powered alarm having a minimum rating of 85 dBa at 10 feet (3048 mm). Water-powered pumps shall have a water efficiency factor of pumping at least 1.4 gallons (5.3 L) of water to a height of 10 feet (3048 mm) for every gallon of water used to operate the pump, measured at a water pressure of 60 psi (414 kPa). Pumps shall be labeled as to the gallons of water pumped per gallon of potable water consumed.

Water-powered stormwater sump pumps shall be equipped with a reduced pressure principle backflow prevention assembly.

L 410.0 Water Softeners and Treatment Devices. L 410.1 Water Softeners. Water softeners shall be listed to NSF 44. Water softeners shall have a rated salt efficiency exceeding 3400 grains (gr) (0.222 kg) of total hardness exchange per pound (0.5 kg) of salt, based on sodium chloride (NaCl) equivalency, and shall not generate more than 4 gallons (15.1 L) of water per 1000 grains (0.0647 kg) of hardness removed during the service cycle.

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L 404.7.3 Time Out and Shut Off. Pulpers, mechanical strainers, and food waste disposers shall have a time out system with push button to reactivate. The maximum allowable run time cycle shall be 10 minutes. L 404.7.4 Sink Drain Outlets. Where a strainer or basket is installed, they shall be readily removable. L 404.7.5 Strainer Baskets. Strainer (scrapper) baskets shall either fit over a sink compartment or be attached to a drain system. The strainer baskets shall be readily removable for emptying. L 404.8 Medical and Laboratory Facilities. Medical and laboratory facilities shall comply with the water efficiency requirements in Section L 404.9 through Section L 404.11. L 404.9 Steam Sterilizers. Controls shall be installed to limit the discharge temperature of condensate or water from steam sterilizers to 140°F (60°C) or less. A venturi-type vacuum system shall not be utilized with vacuum sterilizers. L 404.10 X-Ray Film Processing Units. Processors for X-ray film exceeding 6 inches (152 mm) in any dimension shall be equipped with water recycling units. L 404.11 Exhaust Hood Liquid Scrubber Systems. Liquid scrubber systems for exhaust hoods and ducts shall be of the recirculation type. Liquid scrubber systems for perchloric acid exhaust hoods and ducts shall be equipped with a timer-controlled water recirculation system. The collection sump for perchloric acid exhaust systems shall be designed to drain automatically after the wash down process has completed.

L 405.0 Leak Detection and Control. L 405.1 General. Where installed, leak detection and control devices shall comply with IAPMO IGC 115 or IAPMO IGC 349. Leak detection and control devices help protect property from water damage and also conserve water by shutting off the flow when leaks are detected.

L 406.0 Fountains and Other Water Features. L 406.1 Use of Alternate Water Source for Special Water Features. Special water features such as ponds and water fountains shall be provided with reclaimed (recycled) water, rainwater, or on-site treated nonpotable water where the source and capacity are available on the premises and approved by the Authority Having Jurisdiction.

L 407.0 Meters. L 407.1 Required. A water meter shall be required for buildings connected to a public water system, including municipally supplied reclaimed (recycled) water. In other than single-family houses, multifamily structures of three stories or fewer above grade, and modular houses, a separate meter or submeter shall be installed in the following locations: (1) The water supply for irrigated landscape with an accu mulative area exceeding 2500 square feet (232.3 m 2 ). (2) The water supply to a water-using process where the con sumption exceeds 1000 gallons per day (gal/d) (0.0438 L/s), except for manufacturing processes.

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L 410.2 Water Softener Limitations. In residential buildings, where the supplied potable water hardness is equal to or less than 8 grains per gallon (gr/gal) (137 mg/L) measured as total calcium carbonate equivalents, water softening equipment that discharges water into the wastewater system during the service cycle shall not be allowed, except as required for medical purposes. L 410.3 Point-of-Use Reverse Osmosis Water Treat- ment Systems. Reverse osmosis water treatment systems installed in residential occupancies shall be equipped with automatic shutoff valves to prevent discharge when there is no call for producing treated water. Reverse osmosis water treatment systems shall be listed in accordance with NSF 58.

L 411.0 Landscape Irrigation Systems. L 411.1 General. Where landscape irrigation systems are installed, they shall be in accordance with Section L 411.2 through Section L 411.14. Requirements limiting the amount or type of plant material used in landscapes shall be established by the Authority Having Jurisdiction. Exception: Plants grown for food production. L 411.2 Backflow Protection. Potable water and supplies to landscape irrigation systems shall be protected from backflow in accordance with this code and the Authority Having Jurisdiction. L 411.3 Use of Alternate Water Sources for Land- scape Irrigation. Where available by pre-existing treatment, storage, or distribution network, and where approved by the Authority Having Jurisdiction, alternative water source(s) shall be utilized for landscape irrigation. Where adequate capacity and volumes of pre-existing alternative water sources are available, the irrigation system shall be designed to use a minimum of 75 percent of alternative water for the annual irrigation demand before supplemental potable water is used. L 411.4 Irrigation Control Systems. Where installed as part of a landscape irrigation system, irrigation control systems shall: (1) Automatically adjust the irrigation schedule to respond to

plant water needs determined by weather or soil moisture conditions. (2) Utilize sensors to suspend irrigation during a rainfall. (3) Utilize sensors to suspend irrigation where adequate soil

moisture is present for plant growth. (4) Have the capability to program multiple and different run

times for each irrigation zone to enable cycling of water applications and durations to mitigate water flowing off of the intended irrigation zone. (5) The site-specific settings of the irrigation control system

affecting the irrigation and shall be posted at the control system location. The posted data, where applicable to the settings of the controller, shall include: (a) Precipitation rate for each zone. (b) Plant evapotranspiration coefficients for each zone. (c) Soil absorption rate for each zone. (d) Rain sensor settings.

(e) Soil moisture setting. (f) Peak demand schedule including run times for each zone and the number of cycles to mitigate runoff and monthly adjustments or percentage. L 411.5 Low Flow Irrigation. Irrigation zones using low flow irrigation emitters shall comply with ASABE/ICC 802 Landscape Irrigation Sprinkler and Emitter Standard and shall be equipped with filters sized according to the manufacturer’s recommendation for the specific low flow emitter, and with a pressure regulator installed upstream of the irrigation emission devices as necessary to reduce the operating water pressure in accordance with the manufacturers’ equipment requirements. L 411.6 Mulched Planting Areas. Only low flow emitters are allowed to be installed in mulched planting areas with vegetation taller than 12 inches (305 mm). L 411.7 System Performance Requirements. The landscape irrigation system shall be designed and installed to: (1) Prevent irrigation water from runoff out of the irrigation

zone. (2) Prevent water in the supply line drainage from draining

out between irrigation events. (3) Not allow irrigation water to be applied onto or enter

non-targeted areas including adjacent property and vegetation areas, adjacent hydrozones not requiring the irrigation water to meet its irrigation demand, non-vegetative areas, impermeable surfaces, roadways, and structures. L 411.8 Narrow or Irregularly Shaped Landscape Areas. Narrow or irregularly shaped landscape areas, less than 4 feet (1219 mm) in any direction across opposing boundaries, shall not be irrigated by an irrigation emission device except low flow emitters. L 411.9 Sloped Areas. Where soil surface rises more than 1 foot (305 mm) per 4 feet (1219 mm) of length, the irrigation zone system average precipitation rate shall not exceed 0.75 inches (19.1 mm) per hour as verified through either of the following methods: (1) Manufacturer documentation that the precipitation rate

for the installed sprinkler head does not exceed 0.75 inches (19.1 mm) per hour where the sprinkler heads are installed not closer than the specified radius and where the water pressure of the irrigation system is not more than the manufacturer’s recommendations. (2) Catch can test in accordance with the requirements of the

Authority Having Jurisdiction and where emitted water volume is measured with a minimum of six catchment containers at random places within the irrigation zone for a minimum of 15 minutes to determine the average precipitation rate, expressed as inches per hour (mm/h). L 411.10 Sprinkler Head Installations. All installed sprinkler heads shall comply with ASABE/ICC 802 or other approved standard(s).

L 411.10.1 Sprinkler Heads in Common Irrigation Zones. Sprinkler heads installed in irrigation zones served by a common valve shall be limited to applying water to plants with similar irrigation needs, and shall have

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APPENDIX L

contractors, installers, or designers to demonstrate competency. Where required by the Authority Having Jurisdiction, the contractor, installer, or designer shall be certified to perform such work.

L 412.0 Trap Seal Protection. L 412.1 Water Supplied Trap Primers. Water supplied trap primers shall be electronic or pressure activated and shall use not more than 30 gallons (114 L) per year per drain. Where an alternate water source, as defined by this code, is used for fixture flushing or other uses in the same room, the alternate water source shall be used for the trap primer water supply. Exception: Flushometer tailpiece trap primers in accordance with IAPMO PS 76. L 412.2 Drainage Type Trap Seal Primer Devices. Drainage type trap seal primer devices shall not be limited in the amount of water they discharge.

L 413.0 Vehicle Wash Facilities. L 413.1 Automatic. The maximum make-up water use for automobile washing shall not exceed 40 gallons (151 L) per vehicle for in-bay automatic car washes and 35 gallons (132 L) for conveyor and express type car washes. L 413.2 Self-Service. Spray wands and foamy brushes shall use not more than 3.0 gpm (0.19 L/s). L 413.3 Reverse Osmosis. Spot-free reverse osmosis discharge (reject) water shall be recycled. L 413.4 Towel Ringers. Towel ringers shall have a positive shutoff valve. Spray nozzles shall be replaced annually. Exception: Bus and large commercial vehicle washes are exempt from the requirements of this section.

L 501.0 Water Heating Design, Equipment, and Instal- lation. L 501.1 Scope. The provisions of this section shall establish the means of conserving potable and nonpotable water and energy associated with the generation and use of hot water in a building. This includes provisions for the hot water distribution system, which is the portion of the potable water distribution system between a water heating device and the plumbing fixtures, including dedicated return piping and appurtenances to the water heating device in a recirculation system. L 501.2 Insulation. Hot water supply and return piping shall be thermally insulated. The wall thickness of the insulation shall be equal to the nominal diameter of the pipe up to 2 inches (50 mm). The wall thickness shall be not less than 2 inches (51 mm) for nominal pipe diameters exceeding 2 inches (50 mm). The conductivity of the insulation [k-factor (Btu•in/(h•ft 2 •°F))], measured radially, shall not be more than 0.28 [Btu•in/(h•ft 2 •°F)] [0.04 W/(m•K)]. Hot water piping to be insulated shall be installed such that insulation is continuous. Pipe insulation shall be installed to within 1 ⁄ 4 of an inch (6.4 mm) of appliances, appurtenances, fixtures, structural members, or a wall where the pipe passes through to connect to a fixture within 24 inches (610 mm).

»

matched precipitation rates (identical inches of water application per hour as rated or tested, plus or minus 5 percent). L 411.10.2 Sprinkler Head Pressure Regulation. Sprinkler heads shall utilize pressure regulating devices (as part of an irrigation system or integral to the sprinkler head) to maintain manufacturer’s recommended operating pressure for each sprinkler and nozzle type. L 411.10.3 Pop-up Type Sprinkler Heads. Where pop-up type sprinkler heads are installed, the sprinkler heads shall rise to a height above vegetation level and of not less than 4 inches (102 mm) above the soil level where emitting water. L 411.11 Irrigation Zone Performance Criteria. Irrigation zones shall be designed and installed to ensure the average precipitation rate of the sprinkler heads over the irrigated area does not exceed 1 inch per hour (25.4 mm/h) as verified through either of the following methods: (1) Manufacturer’s documentation that the precipitation rate

for the installed sprinkler head does not exceed 1 inch per hour (25.4 mm/h) where the sprinkler heads are installed not closer that the specified radius and where the water pressure of the irrigation system is not more than the manufacturer’s recommendations. (2) Catch can test in accordance with the requirements of the

Authority Having Jurisdiction and where emitted water volume is measured with a minimum of six catchment containers at random places within the irrigation zone for a minimum of 15 minutes to determine the average precipitation rate, expressed as inches per hour (mm/h). L 411.12 Depth of Irrigation Pipe. Irrigation pipe downstream from the backflow preventer shall be buried at a minimum depth according to Section L 411.12.1 and Section L 411.12.2. L 411.12.1 Landscape Areas. Irrigated landscaped areas not exceeding 10 000 square feet (929 m 2 ) shall have irrigation main lines buried a minimum of 12 inches (305 mm) and irrigation lateral lines buried a minimum of 8 inches (203 mm). Irrigated landscaped areas greater than 10 000 square feet (929 m 2 ) shall have irrigation main lines buried a minimum of 18 inches (457 mm) and irrigation lateral lines buried a minimum of 12 inches (305 mm). L 411.12.2 Vehicular Surfaces. Irrigation pipe installed under vehicular paving and pervious pavers, including landscaped fire lanes, shall be sleeved with a minimum of one 1-inch pipe (25 mm) size greater than the irrigation pipe and buried at a minimum depth of 24 inches (610 mm) in all cases. L 411.13 Backfill. All excavation for irrigation pipe installation shall be backfilled in thin layers to 12 inches (305 mm) with clean earth, which shall not contain stones, boulders, cinderfill, frozen earth, construction debris, or other materials that would damage or break the piping. Fill shall be properly compacted. Suitable precautions shall be taken to ensure permanent stability for pipe laid in filled or made ground. L 411.14 Qualifications. The Authority Having Jurisdiction shall have the authority to require landscape irrigation

2022 CALIFORNIA PLUMBING CODE 493

APPENDIX L

Exceptions: (1) Where the hot water pipe is installed in a wall that is not

of a width to accommodate the pipe and insulation, the insulation thickness shall be permitted to have the maximum thickness that the wall is capable of accommodating and not less than 1 ⁄ 2 of an inch (12.7 mm) thick. (2) Hot water supply piping exposed under sinks, lavatories,

and similar fixtures. L 501.2.1 Pipe Supports. Pipe supports shall be installed on the outside of the pipe insulation. Exception: Vertical supports, and horizontal and vertical anchors shall be installed on the pipe inside the pipe insulation. L 501.3 Recirculation Systems. Recirculation systems shall comply with Section L 501.3.1 and Section L 501.3.2.

L 501.3.1 For Low-Rise Residential Buildings. Circulating hot water systems shall be arranged so that the circulating pump(s) are capable of being turned off (automatically or manually) where the hot water system is not in operation. [ASHRAE 90.2-2007:7.2]

L 501.3.2 For Pumps Between Boilers and Stor- age Tanks. Where used to maintain storage tank water temperature, recirculating pumps shall be equipped with controls limiting operation to a period from the start of the heating cycle to a maximum of 5 minutes after the end of the heating cycle. [ASHRAE 90.1:7.4.4.4] L 501.4 Recirculation Pump Controls. Pump controls shall include on-demand activation or time clocks combined with temperature sensing. Time clock controls for pumps shall not let the pump operate more than 15 minutes every hour. Temperature sensors shall stop circulation where the temperature set point is reached and shall be located on the circulation loop at or near the last fixture. The pump, pump controls, and temperature sensors shall be accessible. Pump operation shall be limited to the building’s hours of operation. L 501.5 Temperature Maintenance Controls. Systems designed to maintain usage temperatures in hot-water pipes, such as recirculating hot water systems or heat trace, shall be equipped with automatic time switches or other controls that are capable of being set to switch off the usage temperature maintenance system during extended periods where hot water is not required. [ASHRAE 90.1:7.4.4.2] L 501.6 System Balancing. Systems with multiple recirculation zones shall be balanced to distribute hot water uniformly, or they shall be operated with a pump for each zone. The circulation pump controls shall comply with the provisions of Section L 501.4. L 501.7 Flow Balancing Valves. Flow balancing valves shall be a factory preset automatic flow control valve, a flow regulating valve, or a balancing valve with memory stop. L 501.8 Air Elimination. Provision shall be made for the elimination of air from the return system. L 501.9 Gravity or Thermosyphon Systems. Gravity or thermosyphon systems are prohibited.

isions of Section L 501.4. L 501.7 Flow Balancing Valves. Flow balancing valves shall be a factory preset automatic flow control valve, a flow regulating valve, or a balancing valve with memory stop. L 501.8 Air Elimination. Provision shall be made for the elimination of air from the return system. L 501.9 Gravity or Thermosyphon Systems. Gravity or thermosyphon systems are prohibited.

L 502.0 Service Hot Water – Low-Rise Residential Buildings. L 502.1 General. The service water heating system for single-family houses, multi-family structures of three stories or fewer above grade, and modular houses shall comply with Section L 502.2 through Section L 502.7.3. The service water heating system of all other buildings shall comply with Section L 503.0. L 502.2 Water Heaters and Storage Tanks. Residentialtype water heaters, pool heaters, and unfired water heater storage tanks shall comply with the minimum performance requirements specified by federal law.

Unfired storage water heating equipment shall have a heat loss through the tank surface area of less than 6.5 British thermal units per square foot hour [Btu/(ft 2 •h)] (20.5 W/m 2 ).

[ASHRAE 90.2-2007:7.1] L 502.3 Recirculation Systems. Recirculation systems shall comply with the provisions of Section L 501.3. L 502.4 Central Water Heating Equipment. Service water heating equipment (central systems) that do not fall under the requirements for residential-type service water heating equipment addressed in Section L 502.2 shall comply with the applicable requirements for service water-heating equipment found in Section L 503.0. [ASHRAE 90.22007:7.3] L 502.5 Insulation. Insulation for hot water and return piping shall comply with the provisions of Section L 501.2. L 502.6 Hard Water. Where water has hardness equal to or exceeding 9 grains per gallon (gr/gal) (154 mg/L) measured as total calcium carbonate equivalents, the water supply line to water heating equipment in new one- and two-family dwellings shall be roughed-in to allow for the installation of water treatment equipment. L 502.7 Maximum Volume of Hot Water. The maximum volume of water contained in hot water distribution pipes shall be in accordance with Section L 502.7.1 or Section L 502.7.2. The water volume shall be calculated using Table L 502.7.

L 502.7.1 Maximum Volume of Hot Water Without Recirculation or Heat Trace. The maximum volume of water contained in hot water distribution pipe between the water heater and any fixture fitting shall not exceed 32 ounces (oz) (946 mL). Where a fixture fitting shutoff valve (supply stop) is installed ahead of the fixture fitting, the maximum volume of water is permitted to be calculated between the water heater and the fitting shutoff valve (supply stop).

or Heat Trace.** The maximum volume of water contained in hot water distribution pipe between the water heater and any fixture fitting shall not exceed 32 ounces (oz) (946 mL). Where a fixture fitting shutoff valve (supply stop) is installed ahead of the fixture fitting, the maximum volume of water is permitted to be calculated between the water heater and the fitting shutoff valve (supply stop).

L 502.7.2 Maximum Volume of Hot Water with Recirculation or Heat Trace. The maximum volume of water contained in the branches between the recirculation loop or electrically heat traced pipe, and the fixture fitting shall not exceed 16 oz (473 mL). Where a fixture fitting shutoff valve (supply stop) is installed ahead of the fixture fitting, the maximum volume of water is permitted to be calculated between the recirculation loop or electrically, heat traced pipe and the fixture fitting shutoff valve (supply stop).

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APPENDIX L

TABLE L 502.7 WATER VOLUME FOR DISTRIBUTION PIPING MATERIALS*
OUNCES OF WATER PER FOOT LENGTH OF PIPING
NOMINAL
SIZE
(inch)

COPPER
M
COPPER
L
COPPER
K
CPVC
CTS
SDR 11
CPVC
**SCH 40 **
**PEX-AL- PEX ** PE-AL- PE CPVC
SCH 80
PEX CTS
SDR 9
PE-RT
SDR 9
**PP SDR 6 ** **PP SDR 7.3 ** PP SDR 11
3⁄8 1.06 0.97 0.84 NA 1.17 0.63 0.63 NA 0.64 0.64 0.91 1.09 1.24
1⁄2 1.69 1.55 1.45 1.25 1.89 1.31 1.31 1.46 1.18 1.18 1.41 1.68 2.12
3⁄4 3.43 3.22 2.90 2.67 3.38 3.39 3.39 2.74 2.35 2.35 2.23 2.62 3.37
1 5.81 5.49 5.17 4.43 5.53 5.56 5.56 4.57 3.91 3.91 3.64 4.36 5.56
11⁄4 8.70 8.36 8.09 6.61 9.66 8.49 8.49 8.24 5.81 5.81 5.73 6.81 8.60
11⁄2 12.18 11.83 11.45 9.22 13.20 13.88 13.88 11.38 8.09 8.09 9.03 10.61 13.47
2 21.08 20.58 20.04 15.79 21.88 21.48 21.48 19.11 13.86 13.86 14.28 16.98 21.39

For SI units: 1 ounce = 29.573 mL

  • NA: Not Applicable

Exception: Whirlpool bathtubs or bathtubs that are not equipped with a shower are exempted from the requirements of Section L 502.7. L 502.7.3 Hot Water System Submeters. Where a hot water pipe from a circulation loop or electric heat trace line is equipped with a submeter, the hot water distribution system downstream of the submeter shall have either an end-of-line hot water circulation pump or shall be electrically heat traced. The maximum volume of water in a branch from the circulation loop or electric heat trace line downstream of the submeter shall not exceed 16 oz (473 mL).

Where there is no circulation loop or electric heat traced line downstream of the submeter, the submeter shall be located within 2 feet (610 mm) of the central hot water system; or the branch line to the submeter shall be circulated or heat traced to within 2 feet (610 mm) of the submeter. The maximum volume from the submeter to each fixture shall not exceed 32 oz (946 mL).

The circulation pump controls shall comply with the provisions of Section L 501.4.

L 503.0 Service Hot Water – Other Than Low-Rise Residential Buildings. L 503.1 General. The service hot water, other than singlefamily houses, multifamily structures of three stories or fewer above grade, and modular houses shall comply with this section.

L 503.1.1 New Buildings. Service water-heating systems and equipment shall comply with the requirements of this section as described in Section L 503.2.

[ASHRAE 90.1:7.1.1.1] L 503.1.2 Additions to Existing Buildings. Service water heating systems and equipment shall comply with the requirements of this section. Exception: Where the service water-heating to an addition is provided by existing service water-heating systems and equipment, such systems and equipment shall not be required to be in accordance with this appendix. However, new systems or equipment installed shall be

in accordance with specific requirements applicable to those systems and equipment. [ASHRAE 90.1:7.1.1.2] L 503.1.3 Alterations to Existing Buildings. Building service water-heating equipment installed as a direct replacement for existing building service water-heating equipment shall be in accordance with the requirements of Section L 503.0 applicable to the equipment being replaced. New and replacement piping shall comply with Section L 503.3.3. Exception: Compliance shall not be required where there is insufficient space or access to meet these requirements. [ASHRAE 90.1:7.1.1.3] L 503.2 Compliance Path(s). Compliance shall be achieved in accordance with the requirements of Section L 503.1, Section L 503.3, Section L 503.4, and Section L 503.5.

[ASHRAE 90.1:7.2.1]

L 503.2.1 Energy Cost Budget Method. Projects using the energy cost budget method of ASHRAE 90.1 for demonstrating compliance with the standard shall be in accordance with the requirements of Section L 503.3 in conjunction with the energy cost budget method of ASHRAE 90.1. [ASHRAE 90.1:7.2.2] L 503.3 Mandatory Provisions. The mandatory provisions of Section L 503.3.1 through Section L 503.3.7 shall be followed.

t Budget Method.** Projects using the energy cost budget method of ASHRAE 90.1 for demonstrating compliance with the standard shall be in accordance with the requirements of Section L 503.3 in conjunction with the energy cost budget method of ASHRAE 90.1. [ASHRAE 90.1:7.2.2] L 503.3 Mandatory Provisions. The mandatory provisions of Section L 503.3.1 through Section L 503.3.7 shall be followed.

L 503.3.1 Load Calculations. Service water-heating system design loads for the purpose of sizing systems and equipment shall be determined in accordance with manufacturer’s published sizing guidelines or accepted engineering standards and handbooks acceptable to the adopting authority (e.g., ASHRAE Handbook – HVAC Applications). [ASHRAE 90.1:7.4.1] L 503.3.2 Equipment Efficiency. Water-heating equipment, hot-water supply boilers used solely for heating potable water, pool heaters, and hot water storage tanks shall comply with the criteria listed in Table L 503.3.2. Where multiple criteria are listed, all criteria shall be met. The omission of minimum performance requirements for certain classes of equipment does not preclude the use of such equipment where appropriate. Equipment not listed in Table L 503.3.2 has no minimum performance requirements.

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APPENDIX L

Exceptions: Water heaters and hot-water supply boilers having more than 140 gallons (530 L) of storage capacity are not required to meet the standby loss (SL) requirements of Table L 503.3.2 where: (1) The tank surface is thermally insulated to R-12.5. (2) A standing pilot light is not installed. (3) Gas- or oil-fired storage water heaters have a flue

damper or fan-assisted combustion. [ASHRAE 90.1:7.4.2] L 503.3.3 Insulation. The following piping shall be insulated in accordance with Table L 503.3.3: (1) Recirculating system piping, including the supply

and return piping of a circulating tank type water heater. (2) The first 8 feet (2438 mm) of outlet piping for a con stant temperature nonrecirculating storage system. (3) The first 8 feet (2438 mm) of branch piping con necting to recirculated, heat-traced, or impedance heated piping. (4) The inlet piping between the storage tank and a heat

trap in a nonrecirculating storage system. (5) Piping that is externally heated (such as heat trace

or impedance heating). [ASHRAE 90.1:7.4.3] L 503.3.4 Hot Water System Design. Hot water systems shall comply with Section L 503.3.4(1) and Section L 503.3.4(2). (1) Recirculation systems shall comply with the provi sions of Section L 501.3. (2) The maximum volume of water contained in hot

water distribution lines between the water heater and the fixture stop or connection to showers, kitchen faucets, and lavatories shall be determined in accordance with Section L 502.7.

L 503.3.5 Service Water Heating System Con- trols. Service water heating system controls shall comply with Section L 503.3.5(1) and Section L 503.3.5(2). (1) Temperature controls shall be provided that allows

for storage temperature adjustment from 120°F (49°C) or lower to a maximum temperature compatible with the intended use. Exception: Where the manufacturer’s installation instructions specify a higher minimum thermostat setting to minimize condensation and resulting corrosion. [ASHRAE 90.1:7.4.4.1] (2) Temperature controlling means shall be provided to

limit the maximum temperature of water delivered from lavatory faucets in public facility restrooms to 110°F (43°C). [ASHRAE 90.1:7.4.4.3] L 503.3.6 Pools. Pool heating systems shall comply with Section L 503.3.6(1) through Section L 503.3.6(3). (1) Pool heaters shall be equipped with a readily acces sible ON/OFF switch to allow shutting off the heater without adjusting the thermostat setting. Pool heaters fired by natural gas shall not have continuously burning pilot lights. [ASHRAE 90.1:7.4.5.1]

(2) Heated pools shall be equipped with a vapor retar dant pool cover on or at the water surface. Pools heated to more than 90°F (32°C) shall have a pool cover with a minimum insulation value of R-12. Exception: Pools that are deriving over 60 percent of the energy for heating from site-recovered energy or solar energy. [ASHRAE 90.1:7.4.5.2] (3) Time switches shall be installed on swimming pool

heaters and pumps. Exceptions: (1) Where public health standards require 24-hour

pump operation. (2) Where pumps are required to operate solar and

waste heat recovery pool heating systems.

[ASHRAE 90.1:7.4.5.3] L 503.3.7 Heat Traps. Vertical pipe risers serving storage water heaters and storage tanks not having integral heat traps and serving a nonrecirculating system shall have heat traps on both the inlet and outlet piping as close as practical to the storage tank. A heat trap is a means to counteract the natural convection of heated water in a vertical pipe run. The means is either of the following: (1) A device specifically designed for the purpose or an

arrangement of tubing that forms a loop of 360 degrees (6.28 rad). (2) Piping that, from the point of connection to the water

heater (inlet or outlet) includes a length of piping directed downward before connection to the vertical piping of the supply water or hot-water distribution system, as applicable. [ASHRAE 90.1:7.4.6] L 503.4 Prescriptive Path. The prescriptive path for space or water heating efficiency shall comply with Section L 503.4.1 through Section L 503.4.5. L 503.4.1 Space Heating and Water Heating. The use of a gas-fired or oil-fired space heating boiler system, otherwise in accordance with Section L 503.0, to provide the total space heating and service water heating for a building is allowed where one of the following conditions is met: (1) The single space-heating boiler, or the component

omply with Section L 503.4.1 through Section L 503.4.5. L 503.4.1 Space Heating and Water Heating. The use of a gas-fired or oil-fired space heating boiler system, otherwise in accordance with Section L 503.0, to provide the total space heating and service water heating for a building is allowed where one of the following conditions is met: (1) The single space-heating boiler, or the component

of a modular or multiple boiler system that is heating the service water, has a standby loss in Btu/h (kW) not exceeding (13.3 × pmd + 400)/ n, where ( pmd ) is the probable maximum demand in gallons per hour, determined in accordance with the procedures described in generally accepted engineering standards and handbooks, and ( n) is the fraction of the year where the outdoor daily mean temperature exceeds 64.9°F (18.28°C).

The standby loss is to be determined for a test period of 24 hours duration while maintaining a boiler water temperature of not less than 90°F (50°C) above ambient, with an ambient temperature between 60°F (16°C) and 90°F (32°C). For a boiler with a modulating burner, this test shall be conducted at the lowest input.

496 2022 CALIFORNIA PLUMBING CODE

APPENDIX L

TABLE L 503.3.2 PERFORMANCE REQUIREMENTS FOR WATER-HEATING EQUIPMENT

MINIMUM EFFICIENCY REQUIREMENTS

[ASHRAE 90.1: TABLE 7.8]

EQUIPMENT TYPE SIZE CATEGORY
(INPUT)
SUBCATEGORY OR
RATING CONDITION
PERFORMANCE REQUIRED1 TEST PROCEDURE2,3
Electric table top water heaters ≤12 kW Resistance ≥20 gal See footnote 7
Electric water heaters ≤12 kW5 Resistance ≥20 gal See footnote 7
Electric water heaters >12 kW5 Resistance ≥20 gal 0.3 + 27√_Vm _%/h Section G.2 of CSA
Z21.10.3
Electric water heaters ≤24 Ampsand
≤250 Volts
Heat Pump See footnote 7
Gas storage water heaters ≤75 000 Btu/h ≥20 gal See footnote 7
Gas storage water heaters >75 000 Btu/h6 <4000 (Btu/h)/gal 80%_Et _(Q/800 +
110√V) SL, Btu/h
Sections G.1and G.2 of
CSAZ21.10.3
Gas instantaneous water
heaters
>50 000 Btu/h and
<200 000 Btu/h
≥4000 (Btu/h)/gal
and <2 gal
See footnote 7
Gas instantaneous water
heaters
≥200 000 Btu/h
4,6
≥4000 (Btu/h)/gal
and <10 gal
80%Et Sections G.1and G.2 of
CSAZ21.10.3
Gas instantaneous water
heaters
≥200 000 Btu/h6 ≥4000 (Btu/h)/gal
and≥10 gal
80%_Et _(Q/799 +
16.6√V) SL, Btu/h
80%_Et _(Q/799 +
16.6√V) SL, Btu/h
Oil storage water heaters ≤105 000 Btu/h ≥20 gal 0.59-0.0005VEF
Oil storage water heaters >105 000 Btu/h <4000 (Btu/h)/gal 80%_Et _(Q/800 +
110√V) SL, Btu/h
Sections G.1and G.2 of
CSAZ21.10.3
Oil instantaneous water heaters ≤210 000 Btu/h ≥4000 (Btu/h)/gal
and <2 gal
See footnote 7
Oil instantaneous water heaters >210 000 Btu/h ≥4000 (Btu/h)/gal
and <10 gal
80%E_t_ Sections G.1and G.2 of
CSAZ21.10.3
Oil instantaneous water heaters >210 000 Btu/h ≥4000 (Btu/h)/gal
and≥10 gal
78%_Et _(Q/800 +
110√V) SL, Btu/h
78%_Et _(Q/800 +
110√V) SL, Btu/h
Hot-water supply boilers, gas
and oil6
≥300 000 Btu/h and
<12 500 000 Btu/h

≥4000 (Btu/h)/gal
and <10 gal
80%E_t_ Sections G.1and G.2 of
CSAZ21.10.3
Hot-water supply boilers, gas6 ≥4000 (Btu/h)/gal
and≥10 gal
80%_Et _(Q/800 +
110√V) SL, Btu/h
80%_Et _(Q/800 +
110√V) SL, Btu/h
Hot-water supply boilers, oil ≥4000 (Btu/h)/gal
and≥10 gal
78%_Et _(Q/800 +
110√V) SL, Btu/h
78%_Et _(Q/800 +
110√V) SL, Btu/h
Pool heaters, oil and gas All See footnote 7 ASHRAE 146
Heat pump pool heaters All 50°F db 44.2°F wb
Outdoor air 80.0°F
entering water
4.0 COP AHRI 1160
Unfired storage tanks All R-12.5 (none)

For SI units: 1 gallon = 3.785 L, 1000 British thermal units per hour = 0.293 kW, °C = (°F-32)/1.8 Notes: 1 Thermal efficiency ( Et ) is a minimum requirement, while standby loss (SL) is maximum Btu/h (kW) based on a 70°F (21°C) temperature difference between stored water and ambient requirements. In the SL equation, V is the rated volume in gallons and Q is the nameplate input rate in Btu/h (kW). Vm is the measured volume in the tank in gallons. 2 ASHRAE 90.1 contains a complete specification, including the year version, of the referenced test procedure. 3 Section G.1 is titled “Test Method for Measuring Thermal Efficiency” and Section G.2 is titled “Test Method for Measuring Standby Loss.” 4 Instantaneous water heaters with input rates below 200 000 Btu/h (58.6 kW) shall be in accordance with these requirements where the water heater is designed to heat water to temperatures of 180°F (82°C) or higher. 5 Electric water heaters with input rates less than 40 946 Btu/h (12 kW) shall be in accordance with these requirements where the water heater is designed to heat water to temperatures of 180°F (82°C) or higher. 6 Refer to Section L 503.4.3 for additional requirements for gas storage and instantaneous water heaters and gas hot water supply boilers. 7 In the U.S., the efficiency requirements for water heaters or gas pool heaters in this category or subcategory are specified by the U.S. Department of Energy. Those requirements and applicable test procedures are found in the Code of Federal Regulations 10 CFR Part 430.

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APPENDIX L

TABLE L 503.3.3 MINIMUM PIPING INSULATION THICKNESS FOR HEATING AND HOT-WATER SYSTEMS (STEAM, STEAM CONDENSATE, HOT-WATER HEATING, AND DOMESTIC WATER SYSTEMS) 1, 2, 3, 4, 5

[ASHRAE 90.1: TABLE 6.8.3-1]

FLUID OPERATING
TEMPERATURE
RANGE AND
USAGE (°F)
INSULATION CONDUCTIVITY ≥NOMINAL PIPE SIZE OR TUBE SIZE (inches)
FLUID OPERATING
TEMPERATURE
RANGE AND
USAGE (°F)
CONDUCTIVITY
Btu•inch/(h•ft2•°F)
MEAN RATING
TEMPERATURE
(°F)
<1 1 to <11⁄2 11⁄2 to <4 4 to <8 ≥8
INSULATION THICKNESS (inches) INSULATION THICKNESS (inches) INSULATION THICKNESS (inches) INSULATION THICKNESS (inches) INSULATION THICKNESS (inches)
>350 0.32 to 0.34 250 4.5 5.0 5.0 5.0 5.0
251 to 350 0.29 to 0.32 200 3.0 4.0 4.5 4.5 4.5
201 to 250 0.27 to 0.30 150 2.5 2.5 2.5 3.0 3.0
141 to 200 0.25 to 0.29 125 1.5 1.5 2.0 2.0 2.0
105 to 140 0.22 to 0.28 100 1.0 1.0 1.5 1.5 1.5

For SI units: °C=(°F-32)/1.8, 1 British thermal unit inch per hour square foot degree Fahrenheit = [0.1 W/(m•K)], 1 inch = 25 mm Notes: 1 For insulation outside the stated conductivity range, the minimum thickness ( T ) shall be determined as follows: T = r {(1 + t / r ) K / k - 1} Where: T = minimum insulation thickness (inches) (mm). r = actual outside radius of pipe (inches) (mm). t = insulation thickness listed in this table for applicable fluid temperature and pipe size. K = conductivity of alternate material at mean rating temperature indicated for the applicable fluid temperature [Btu•in/(h•ft 2 •°F)] [W/(m•K)]. k = the upper value of the conductivity range listed in this table for the applicable fluid temperature. 2 These thicknesses are based on energy efficiency considerations only. Additional insulation is sometimes required relative to safety issues or surface temperature. 3 For piping 11 ⁄ 2 inches (40 mm) or less, and located in partitions within conditioned spaces, reduction of insulation thickness by 1 inch (25.4 mm) shall be permitted before thickness adjustment required in Footnote 1, but not a thickness less than 1 inch (25.4 mm). 4 For direct-buried heating and hot water system piping, reduction of insulation thickness by 11 / 2 inch (38 mm) shall be permitted before thickness adjustment required in Footnote 1, but not a thickness less than 1 inch (25.4 mm). 5 Table L 503.3.3 is based on steel pipe. Non-metallic pipes, Schedule 80 thickness or less shall use the table values. For other non-metallic pipes having a thermal resistance more than that of steel pipe, reduced insulation thicknesses shall be permitted where documentation is provided showing that the pipe with the proposed insulation has no more heat transfer per foot (mm) than a steel pipe of the same size with the insulation thickness shown in Table L 503.3.3.

(2) It is demonstrated to the satisfaction of the Author ity Having Jurisdiction that the use of a single heat source will consume less energy than separate units. (3) The energy input of the combined boiler and water

heater system is less than 150 000 British thermal units per hour (Btu/h) (44 kW). [ASHRAE 90.1:7.5.1]

L 503.4.2 Service Water Heating Equipment. Service water-heating equipment used to provide the additional function of space heating as part of a combination (integrated) system shall satisfy stated requirements for the service water-heating equipment.

[ASHRAE 90.1:7.5.2]

L 503.4.3 Buildings with High-Capacity Service Water Heating Systems. New buildings with gas service hot-water systems with a total installed gas waterheating input capacity of 1 000 000 Btu/h (293 kW) or more, shall have gas service water-heating equipment with a thermal efficiency ( Et ) of not less than 90 percent. Multiple units of gas water-heating equipment shall be permitted to comply with this requirement where the water-heating input provided by the equipment, with thermal efficiency ( Et ) of more or less than 90 percent, provides an input capacity-weighted average thermal efficiency of not less than 90 percent.

water-heating equipment with a thermal efficiency ( Et ) of not less than 90 percent. Multiple units of gas water-heating equipment shall be permitted to comply with this requirement where the water-heating input provided by the equipment, with thermal efficiency ( Et ) of more or less than 90 percent, provides an input capacity-weighted average thermal efficiency of not less than 90 percent.

Exceptions: (1) Where 25 percent of the annual service water-heat ing requirement is provided by site-solar or siterecovered energy. (2) Water heaters installed in individual dwelling units. (3) Individual gas water heaters with input capacity,

not more than 100 000 Btu/h (29.3 kW). [ASHRAE 90.1:7.5.3] L 503.4.4 Heat Recovery for Service Water Heating. Condenser heat recovery systems shall be installed for heating or preheating of service hot water provided the following are true: (1) The facility operates 24 hours a day. (2) The total installed heat rejection capacity of the

water-cooled systems exceeds 6 000 000 Btu/h (1758 kW) of heat rejection. (3) The design service water-heating load exceeds 1 000

000 Btu/h (293 kW). [ASHRAE 90.1:6.5.6.2.1] L 503.4.5 Capacity. The required heat recovery system shall have the capacity to provide the smaller of: (1) Sixty percent of the peak heat-rejection load at

design conditions. (2) Preheat of the peak service hot-water draw to 85°F

(29°C).

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Exceptions: (1) Facilities that employ condenser heat recovery for

space heating with a heat recovery design exceeding 30 percent of the peak water-cooled condenser load at design conditions. (2) Facilities that provide 60 percent of their service

water heating from site-solar or site-recovered energy or other sources. [ASHRAE 90.1:6.5.6.2.2] L 503.5 Submittals. The Authority Having Jurisdiction shall require submittal of compliance documentation and supplemental information in accordance with Section 104.3.1 of this code.

L 504.0 Solar Water Heating Systems. L 504.1 General. The erection, installation, alteration, addition to, use or maintenance of solar water heating systems shall be in accordance with this section and the Uniform Solar Energy and Hydronics Code. L 504.2 Annual Inspection and Maintenance. Solar energy systems that utilize a heat transfer fluid shall annually be inspected unless inspections are required on a more frequent basis by the solar energy system manufacturer.

L 505.0 Hard Water. L 505.1 Softening and Treatment. Where water has a hardness equal to or exceeding 10 gr/gal (171 mg/L) measured as total calcium carbonate equivalents, the water supply line to water heating equipment and the circuit of boilers shall be softened or treated to prevent accumulation of limescale and consequent reduction in energy efficiency.

L 506.0 Drain Water Heat Exchangers. L 506.1 General. Drain water heat exchangers shall comply with IAPMO PS 92. The heat exchanger shall be accessible.

L 507.0 Heat Recovery from Steam Boiler Blowdown. L 507.1 General. Where heat recovery can be used beneficially to heat boiler makeup water or for other purposes, boiler blowdown from steam boilers exceeding 15 psi (103 kPa) and 3.4 E+06 Btu/h (996 kW) shall be directed to a heat recovery system that reduces the temperature of the blowdown discharge to below 140°F (60°C) without using tempering water.

L 601.0 Installer Qualifications. L 601.1 Scope. The provisions of this section address minimum qualifications of installers of plumbing and mechanical systems covered within the scope of this appendix.

L 602.0 Qualifications. L 602.1 General. Where permits are required, the Authority Having Jurisdiction shall have the authority to require contractors, installers, or service technicians to demonstrate

APPENDIX L

competency. Where determined by the Authority Having Jurisdiction, the contractor, installer, or service technician shall be licensed to perform such work.

L 701.0 Method of Calculating Water Savings. L 701.1 Purpose. The purpose of this section is to provide a means of estimating the water savings where installing plumbing and fixture fittings that use less water than the maximum required by the Energy Policy Act of 1992 and 2005 and this code. L 701.2 Calculation of Water Savings. Table L 701.2(1) and Table L 701.2(2) shall be permitted to be used to establish a water use baseline in calculating the amount of water saved as a result of using plumbing fixtures and fixture fittings that use less water than the required maximum. Water use is determined by the following equation: Water use = (flow rate or consumption) x (duration) x (occupants) x (daily uses)

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APPENDIX L

TABLE L 701.2(1) WATER USE BASELINE5 5
FIXTURE TYPE MAXIMUM FLOW-RATE
** CONSUMPTION2**
DURATION ESTIMATED DAILY
USES PER PERSON
OCCUPANTS3, 4
Showerheads 2.5 gpm at 80 psi 8 minutes 1
Private or Private Use Lavatory Faucets 2.2 gpm at 60 psi 0.25 minutes 4
Residential Kitchen Faucets 2.2 gpm at 60 psi 4 minutes 1
Wash Fountains One 2.2 gpm at 60 psi fixture fitting
for every 20 inches rim space
Lavatory Faucets in other than Residences,
Apartments, and Private Bathrooms in
Lodging Facilities
0.5 gpm 0.25 minutes 4
Metering Faucets 0.25 gallons/cycle 3
Metering Faucets for Wash Fountains One 0.25 gallon per cycle fixture
fitting for every 20 inches rim space
Water Closets 1.6 gallons per flush 1 flush 1 male1
Water Closets 1.6 gallons per flush 1 flush 3 female
Urinals 1.0 gallons per flush 1 flush 2 male

For SI units: 1 gallon per minute = 0.06 L/s, 1 pound-force per square inch = 6.8947 kPa, 1 gallon = 3.785 L, 1 inch = 25.4 mm Notes: 1 The daily use number shall be increased to three where urinals are not installed in the room. 2 The maximum flow rate or consumption is from the Energy Policy Act. 3 For residential occupancies, the number of occupants shall be based on two persons for the first bedroom and one additional person for each additional bedroom. 4 For nonresidential occupancies, refer to Table 422.1 for occupant load factors. 5 Where determining calculations, assume one use per person for metering or self-closing faucets.

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APPENDIX L

TABLE L 701.2(2) WATER SAVINGS CALCULATOR1, 2, 3
NONRESIDENTIAL BUILDINGS NONRESIDENTIAL BUILDINGS NONRESIDENTIAL BUILDINGS NONRESIDENTIAL BUILDINGS NONRESIDENTIAL BUILDINGS NONRESIDENTIAL BUILDINGS
FIXTURE TYPE CONSUMPTION
(gallons per minute)
DAILY USES DURATION
(minutes)
OCCUPANTS DAILY WATER
USES (gallons)
1.6 gpf (gallons per flush) toilet - male 1.6 1 1 150 240
1.6 gpf toilet - female 1.6 3 1 150 720
1.0 gpf urinal - male 1 2 1 150 300
Commercial lavatory faucet - 0.5 gpm 0.5 3 0.25 300 113
Kitchen sink - 2.2 gpm 2.2 1 0.25 300 165
Showerhead - 2.5 gpm 2.5 0.1 8 300 600
Total Daily Volume 2138
Annual Work Days 260
Total Annual Usage 555 750

NONRESIDENTIAL BUILDINGS

FIXTURE TYPE CONSUMPTION
(gallons per minute)
DAILY USES DURATION
(minutes)
OCCUPANTS DAILY WATER
USES (gallons)
1.6 gpf toilet - male 1.28 1 1 150 192
1.6 gpf toilet - female 1.28 3 1 150 576
1.0 gpf urinal - male 0.5 2 1 150 150
Commercial lavatory faucet - 0.5 gpm 0.5 3 0.25 300 113
Kitchen sink - 2.2 gpm 2.2 1 0.25 300 165
Showerhead - 2.5 gpm 2.5 0.1 8 300 600
Total Daily Volume 1796
Annual Work Days 260
Total Annual Usage 466 830
Annual Savings 88 920
% Reduction -16.0 percent

For SI units: 1 gallon per minute = 0.06 L/s, 1 gallon = 3.785 L Notes: 1 Consumption values shown as underlined reflect the maximum consumption values associated with the provisions called out in the IAPMO Green Plumbing & Mechanical Code Supplement. 2 Where metering faucets are used, insert the flow rate of the faucet in the “Consumption” column and insert the cycle time in the “Duration” column (assume 1 cycle per use). 3 To determine estimated savings, insert occupant values (same as Baseline) and consumption values based on fixtures and fixture fittings installed.

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APPENDIX L

TABLE L 701.2(2) (continued) WATER SAVINGS CALCULATOR1, 2
NONRESIDENTIAL BUILDINGS NONRESIDENTIAL BUILDINGS NONRESIDENTIAL BUILDINGS NONRESIDENTIAL BUILDINGS NONRESIDENTIAL BUILDINGS NONRESIDENTIAL BUILDINGS
FIXTURE TYPE CONSUMPTION
(gallons per minute)
DAILY USES DURATION
(minutes)
OCCUPANTS DAILY WATER
USES (gallons)
1.6 gpf toilets 1.6 5 1 4 32
Lavatory faucet - 2.2 gpm 2.2 8 0.25 4 18
Kitchen sink - 2.2 gpm 2.2 6 0.25 4 13
Showerhead - 2.5 gpm 2.5 0.75 8 4 60
Total Daily Volume 123
Annual Work Days 44 822

NONRESIDENTIAL BUILDINGS

FIXTURE TYPE CONSUMPTION
(gallons per minute)
DAILY USES DURATION
(minutes)
OCCUPANTS DAILY WATER
USES (gallons)
1.6 gpf toilet - male 1.28 5 1 4 26
Lavatory faucet - 1.5 gpm 1.5 8 0.25 4 12
Kitchen sink - 2.2 gpm 2.2 6 0.25 4 13
Showerhead - 2.5 gpm 2.5 0.75 8 4 60
Total Daily Volume 111
Annual Usage 40 442
Annual Savings 4380
% Reduction -9.8 percent

For SI units: 1 gallon per minute = 0.06 L/s, 1 gallon = 3.785 L Notes: 1 Consumption values shown as underlined reflect the maximum consumption values associated with the provisions called out in the IAPMO Green Plumbing & Mechanical Code Supplement. 2 To determine estimated savings, insert occupant values (same as Baseline) and consumption values based on fixtures and fixture fittings installed.

Notes and instructions for Table L 701.2(2): Table L 701.2(2) is an example of a calculator that is capable of helping estimate water savings in residential and nonresidential structures. The “Duration” of use and “Daily Uses” values that appear in the table are estimates and based on previous studies. The first example shown below is a commercial office building with 300 occupants, 150 females, and 150 males. The second example is a 3 bedroom residential building. To obtain and use a working copy of this calculator, follow the download and use instructions below. Instructions for download:

  1. Go to the IAPMO website at www.iapmogreen.org to download the water savings calculator. The calculator is a Microsoft Office Excel file (1997 or later), your computer must be capable of running MS Excel.
  2. Follow the instructions for downloading and running the file.

Instructions for use:

  1. In the Baseline Case section, insert the number of total occupants, male occupants and female occupants that apply to the building in the “Occupants” column. Unless specific gender ratio values are provided, assume a 50/50 gender ratio.
  2. Copy and paste these same values in the “Occupants” column of the Calculator section.
  3. In the Calculator section, insert the consumption values (flow rates in gpm or gallons per flush or per cycle) in the “Consumption” column.
  4. Estimated water savings regarding percent savings versus baseline values, gallons per day and gallons per year will be automatically calculated.

502 2022 CALIFORNIA PLUMBING CODE

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