- Only potable water shall be supplied to plumbing fixtures used for drinking, bathing, culinary use or the processing of food, medical or pharmaceutical products.
- Reclaimed non-potable water shall be permitted in other than single dwelling units for flushing water closets and urinals, landscape irrigation, and other reuse applications in accordance with the requirements of the Authority Having Jurisdiction.
- Graywater in single dwelling units shall be limited to subsurface landscape irrigation in accordance with the requirements of the Authority Having Jurisdiction.
- Graywater in other than single dwelling units that is filtered and disinfected shall be permitted to be used for flushing water closets and urinals in accordance with the requirements of the Authority Having Jurisdiction.
- Harvested rainwater in other than single dwelling units that is filtered shall be permitted to be used for flushing water closets and urinals and subsurface landscape irrigation in accordance with the requirements of the Authority Having Jurisdiction.
- Reclaimed non-potable water, graywater, and harvested rainwater, including the collection piping, distribution piping, storage and pumping equipment, shall be part of the plumbing system as covered by this Code regardless of their location on the property.
CROSS CONNECTION CONTROL BY INDIVIDUAL OUTLET PROTECTION
CROSS CONNECTION CONTROL BY CONTAINMENT OF THE BUILDING
- Private potable water supplies (i.e., wells, cisterns, lakes, streams) shall require the same backflow prevention that is required for a public potable water supply.
- Cross connection between a private potable water supply and a public potable water supply shall not be made unless specifically approved by the Authority Having Jurisdiction in accordance with N.J.A.C. 7:10-10.2(e).
- Piping conveying potable water shall be constructed of non-toxic material.
- The interior surface of a potable water tank shall not be lined, painted, or repaired with any material that will affect the taste, odor, color or potability of the water supply when the tank is placed in or returned to service.
- The water supply outlets for plumbing fixtures and other discharges shall be protected from backsiphonage by a fixed air gap or a required backflow preventer.
- Air gaps shall comply with ASME A112.1.2 or Table 10.5.2. Air gap fittings shall comply with ASME A112.1.3.
- How Measured: Air gaps shall be measured vertically from the lowest opening of the water supply outlet to either (1) the flood level rim of the fixture or receptor served, or (2) the maximum elevation of the source of contamination.
- Minimum size (distance): The minimum required air gap shall be in accordance with Table 10.5.2 based on the opening of the water supply outlet and the affect of any nearby vertical surfaces (walls).Figure 10.5.2
MINIMUM REQUIRED AIR GAPS
MINIMUM AIR GAPS FOR FIXTURES, APPLIANCES, AND WATER SUPPLY OUTLETS
Water Supply Outlet Size Minimum Air Gap Not Affected by Near Walls Affected by One Near Wall Affected by Two Near Walls Outlets not greater than 1/2-inch diameter, including lavatory faucets 1 inch 1-1/2 inches 2 inches Outlets not greater than 3/4-inch diameter, including sink faucets 1-1/2 inches 2-1/4 inches 3 inches Outlets not greater than 1-inch diameter, including bathtub spouts 2 inches 3 inches 4 inches Outlets greater than 1-inch diameter 2 times diameter 3 times diameter 4 times diameterNOTES FOR TABLE 10.5.2:
- The listed outlet diameters in Table 10.5.2 are 1/2-inch, 3/4-inch, 1-inch, and greater than 1-inch. They should be used to determine the affect of near walls (vertical surfaces) in Notes 2, 3, and 4 and the minimum required air gap.
- The minimum air gaps for water supply outlets are not affected by near walls if a single wall is more than 3 times the listed outlet diameter clearance from an edge of the outlet. If there are two walls, the clearances from both must be more than 4 times the listed outlet diameter for the air gap to be not affected.
- If a water supply outlet has one near wall and the clearance is less than 3 times the listed outlet diameter from an edge of the outlet, the air gap must be sized as affected by one near wall.
- If a water supply outlet has two near walls that both have clearances that are less than 4 times the listed outlet diameter from an edge of the outlet, the air gap must be sized as affected by two near walls.
With Continuous Water Pressure (CWP)
CWP, Backsiphonage, High or Low Hazard
- ASSE 1020: pressure vacuum breaker assembly
- ASSE 1056: spill resistant vacuum breaker assembly
- CSA B64.1.2: pressure vacuum breaker (PVB)
- CSA B64.1.3: spill resistant pressure vacuum breaker (SRPVB)
CWP, Backsiphonage, Backpressure, Low Hazard
- ASSE 1012: backflow preventer with intermediate atmospheric vent
- ASSE 1015 (DC): double check backflow preventer assembly
- ASSE 1015 (DCF): double check fire protection backflow preventer assembly
- ASSE 1022: backflow preventer for beverage dispensing equipment
- ASSE 1024: dual check backflow preventer
- ASSE 1032: dual check valve type backflow preventer for carbonated beverage dispensers, post mix type
- ASSE 1048 (DCDA): double check detector fire protection backflow preventer assembly
- ASSE 1048 (DCDA-II): double check detector fire protection backflow preventer assembly
- AWWA C510: double check valve backflow prevention assembly
- CSA B64.3: dual check valve backflow preventer with atmospheric port (CDAP)
- CSA B64.3.1: dual check valve backflow preventer with atmospheric port for carbonators (DCAPC)
- CSA B64.5: double check valve (DCVA) backflow preventer
- CSA B64.5.1: double check valve backflow preventer for fire protection (DCVAF)
- CSA B64.6: dual check valve (DuC) backflow preventer
- CSA B64.6.1: dual check valve backflow preventer for fire protection systems (DuCF)
CWP, Backsiphonage, Backpressure, High or Low Hazard
- ASSE 1013 (RP): reduced pressure principle backflow preventer
- ASSE 1013 (RPF): reduced pressure principle fire protection backflow preventer
- ASSE 1047 (RPDA): reduced pressure detector fire protection backflow prevention assembly
- ASSE 1047 (RPDA-II): reduced pressure detector fire protection backflow prevention assembly
- AWWA C511: reduced pressure principle backflow-prevention assembly
- CSA B64.4: reduced pressure principle (RP) backflow preventer
- CSA B64.4.1: reduced pressure principle backflow-preventer for fire protection (RPF)
Not with Continuous Water Pressure (NCWP)
NCWP, Backsiphonage, High or Low Hazard
- ASME A112.1.2: air gap in plumbing systems
- ASME A112.1.3: air gap fitting for use in plumbing fixtures, appliances, and appurtenances
- ASSE 1001: atmospheric type vacuum breaker
- ASSE 1002: anti-siphon fill valve for water closet and urinal flush tanks
- ASSE 1021: drain air gap for domestic dishwasher applications
- CSA B64.1.1: atmospheric vacuum breaker (AVB)
NCWP, Backsiphonage, Limited Backpressure, High or Low Hazard
- ASSE 1011: hose connection vacuum breaker
- ASSE 1019: wall hydrant with backflow prevention and freeze resistance
- ASSE 1035: laboratory faucet backflow preventer
- ASSE 1052: dual check hose connection backflow-preventer
- ASSE 1053: dual check backflow preventer wall hydrant - freeze resistant
- ASSE 1057 (I-V): freeze resistant sanitary yard hydrant with backflow prevention
- CSA B64.2: hose connection vacuum breaker (HCVB)
- CSA B64.2.1: hose connection vacuum breaker with manual drain (HCVB)
- CSA B18.104.22.168: hose connection dual check vacuum breaker (HCDVB)
- CSA B64.2.2: hose connection vacuum breaker with automatic drain (HCVB)
- CSA B64.7: laboratory faucet vacuum breaker (LFVB)
- CSA B125.3: anti-siphon fill valve for water closet and urinal flush tanks
- The backpressure on the following backflow preventers for hose connections shall be limited to 10 feet of water from an elevated hose: ASSE 1011, ASSE 1019, ASSE 1053, ASSE 1057 (I-V), CSA B22.214.171.124.
- The backpressure on the following backflow preventers for laboratory faucets shall be limited to 6 inches of water from an elevated discharge hose: ASSE 1035, CSA B64.7.
- All Types: All backflow preventers shall be accessible for testing (if testable), maintenance, repair, and replacement. Clearances shall be as recommended by the manufacturer. Backflow preventers having atmospheric vents shall not be installed in pits, vaults, or similar potentially submerged locations. Vacuum breakers and other devices with vents shall not be located within fume hoods. Where outdoor enclosures are provided for backflow prevention assemblies, they shall comply with ASSE 1060.
- Atmospheric Vacuum Breakers: Pipe-applied atmospheric vacuum breakers shall be installed with the critical level not less than six inches above the flood level rim or highest point of discharge of the fixture being served. Approved deck-mounted and pipe-applied vacuum breakers and vacuum breakers within equipment, machinery and fixtures where the critical level is a specified distance above the source of contamination shall be installed in accordance with manufacturer's instructions with the critical level not less than one inch above the flood level rim. Such devices shall be installed on the discharge side of the last control valve to the fixture and no shutoff valve or faucet shall be installed downstream of the vacuum breaker. Vacuum breakers on urinals shall be installed with the critical level not less than six inches above the highest part of the urinal. See Figures 10.5.5-A through 10.5.5-F.
- Pressure Type Vacuum Breakers: Pressure type vacuum breakers shall be installed with the critical level at a height of at least 12 inches above the flood level rim for ASSE 1020 devices and with the critical level at least six inches above the flood level rim or highest point of discharge of the fixture being served for ASSE 1056 devices. Deck-mounted and pipe-applied pressure type (ASSE 1056) vacuum breakers within equipment, machinery and fixtures where the critical level is a specified distance above the source of contamination shall be installed in accordance with manufacturer's instructions with the critical level not less than one inch above the flood level rim. See Figure 10.5.5-G.
- Double Check Valves and Reduced Pressure Principle Valves: Such devices shall be installed at not less than 12 inches above the floor or permanent platform with the maximum of 60 inches above floor or permanent platform. See Figures 10.5.5-H and -I.
- Spill Resistant Vacuum Breaker Assemblies: Approved deck-mounted and pipe-applied spill resistant vacuum breaker assemblies within equipment, machinery and fixtures where the critical level is a specified distance above the source of contamination shall be installed in accordance with manufacturer's instructions with the critical level not less than one inch above the flood level rim.
THE POTABLE WATER SUPPLY TO A COMMERCIAL FOOD WASTE DISPOSER PROTECTED BY AN ATMOSPHERIC VACUUM BREAKER
THE POTABLE WATER SUPPLY TO A SERVICE SINK
THE POTABLE WATER SUPPLY TO A LAB SINK PROTECTED BY AN ATMOSPHERIC VACUUM BREAKER
THE POTABLE WATER SUPPLY TO AN ASPIRATING DEVICE PROTECTED BY AN ATMOSPHERIC VACUUM BREAKER
THE POTABLE WATER SUPPLY TO A WATER CLOSET OR URINAL PROTECTED BY AN ATMOSPHERIC VACUUM BREAKER
THE POTABLE WATER SUPPLY TO A WATER CLOSET GRAVITY FLUSH TANK PROTECTED BY AN ANTI-SIPHON BALL COCK WITH INTEGRAL VACUUM BREAKER
THE POTABLE WATER SUPPLY TO INDUSTRIAL PROCESS EQUIPMENT PROTECTED BY A PRESSURE VACUUM BREAKER
THE POTABLE WATER SUPPLY TO A NON-HEALTH HAZARD BACKFLOW APPLICATION PROTECTED BY A DOUBLE CHECK VALVE ASSEMBLY
THE POTABLE WATER SUPPLY TO A HEALTH HAZARD BACKFLOW APPLICATION PROTECTED BY A REDUCED PRESSURE BACKFLOW PREVENTER ASSEMBLY
- Assemblies that are designed to be field tested shall be tested prior to final inspection of the initial installation and once each year thereafter.
- Assemblies installed in a building potable water supply distribution system for protection against backflow shall be maintained in good working condition and be repaired when necessary.
- Testable assemblies are those backflow prevention assemblies having test cocks or test procedures and include, but are not limited, to the following:
- Reduced pressure principle backflow preventers (ASSE 1013)
- Reduced pressure fire protection principle backflow preventers (ASSE 1013)
- Double check backflow prevention assemblies (ASSE 1015)
- Double check fire protection backflow prevention assemblies (ASSE 1015)
- Pressure vacuum breaker assemblies (ASSE 1020)
- Reduced pressure detector fire protection backflow prevention assemblies (ASSE 1047)
- Double check detector fire protection backflow prevention assemblies (ASSE 1048)
- Spill resistant vacuum breakers (ASSE 1056)
- Where tests indicate that the assembly is not functioning properly, it shall be serviced or repaired in accordance with the manufacturer's instructions and be retested.
- Testing of assemblies shall be performed by certified individuals.
- Certification for testing and repair shall be in accordance with the appropriate sections of ASSE 5000 Cross-Connection Control Professional Qualification Standard. Testing shall be in accordance with ASSE 5110 Backflow Prevention Assembly Testers. Repair shall be in accordance with ASSE 5130 Backflow Prevention Assembly Repairers.
- Copies of test reports for the initial installation shall be sent to the Authority Having Jurisdiction and the water supplier. Copies of annual test reports shall be sent to the water supplier.
- Where a continuous water supply is critical and cannot be interrupted for the periodic testing of a backflow prevention assembly, multiple backflow prevention assemblies or other means of maintaining a continuous supply shall be provided that does not create a potential cross connection.
- Where a potable water inlet terminates below the rim of the tank or vat and the tank or vat has an overflow of a diameter not less than given in Table 10.8.3, the overflow pipe shall be provided with an air gap as close to the tank as possible.
- The potable water supply inlet to the tank or vat shall terminate a distance not less than 1-1/2 times the height to which water can rise in the tank above the top of the overflow. This level shall be established at the maximum flow rate of the supply to the tank or vat and with all outlets closed except the air-gapped overflow outlet.
- An alternate to 10.5.7.b is a vacuum breaker on the water supply inlet pipe above the rim of the tank or vat.
A POTABLE WATER TANK OR VAT WITH ITS INLET BELOW THE OVERFLOW RIM
- Food preparation and service equipment in food establishments that is connected to potable water piping or drained to waste piping shall be protected from backflow to the potable water system and from contamination of equipment, food, and utensils.
- Fixtures that require an air gap in their water supply above the flood level rim of the fixture include, but are not limited to, sink faucets, dipper wells, pot fillers, and spray arms in dish areas.
- Equipment that requires an air gapped waste line includes, but is not limited to, walk-in coolers, food prep sinks, dipper wells, ice machines, ice bins, steam tables, bains-marie, Chinese ranges (woks), combination steamer/ovens, rethermalizers, steamers, kettles, non-evaporating reach-in coolers, soda gun holsters, and water treatment systems.
- Equipment that requires a pressure vacuum breaker or spill resistant vacuum breaker in its water supply includes, but is not limited to, Chinese ranges (woks), rethermalizers, hoses with a pressure nozzle, and pasta cookers.
- Equipment that requires an atmospheric vacuum breaker in its water supply includes, but is not limited to, garbage disposals, automatic dishwashers, dish machine automatic detergent feeders, detergent feeders for 3-compartment sinks, wall-mounted chemical feeders, garbage can washers, mop sinks, steam tables with submerged inlets, and dish troughs with submerged inlets.
- Equipment that requires a vented double check valve or equivalent in its water supply includes, but is not limited to, untreated boilers such as expresso machines, the oven in combination steamer/ovens, carbonated beverage machines, beverage carbonators, non-carbonated beverage machines, coffee machines, iced tea machines, hot chocolate machines, cappuccino machines, instant hot water dispensers, slushy machines, and any other beverage equipment.
- The water supply to a post-mix carbonated beverage dispenser shall be protected against backflow with an integral backflow preventer conforming to ASSE 1022 or an air gap.
- Post-mix carbonated beverage dispensers and carbonated beverage systems with an integral dual check backflow preventer without an atmospheric vent (ASSE 1032) or without an integral backflow preventer conforming to ASSE 1022 or without an integral air gap shall have the water supply connection to the dispenser protected by a double check valve with atmospheric vent port conforming to ASSE 1022.
- When an ASSE 1022 device must be installed in the water supply piping external to the carbonated beverage dispenser, the piping from the device to the beverage dispenser shall be acid-resistant and not copper.
- ASSE 1012 backflow preventers with intermediate atmospheric vents are not constructed for use with carbonated beverages and shall not be used for backflow prevention from post-mix carbonated beverage dispensers.
- All backflow prevention assemblies and devices shall be installed in accordance with their manufacturer's instructions for the particular application.
- Potable water supplies to water-based fire protection systems, including but not limited to standpipes and automatic sprinkler systems, shall be protected from backpressure and backsiphonage by one of the following testable assemblies:
- double check fire protection backflow prevention assembly — ASSE 1015 (DCF)
- double check detector fire protection backflow prevention assembly — ASSE 1048 (DCDA or DCDA-II)
- reduced pressure fire protection principle backflow prevention assembly — ASSE 1013 (RPF)
- reduced pressure detector fire protection backflow prevention assembly — ASSE 1047 (RPDA or RPDA-II).EXCEPTIONS:
- ASSE 1024 dual check backflow preventers shall be permitted in stand-alone residential fire sprinkler systems that comply with NFPA 13D or NFPA 13R, do not supply plumbing fixtures, and do not include a fire department connection.
- Backflow preventers shall not be required in NFPA 13D multipurpose or network residential fire sprinkler systems that supply both plumbing fixtures and residential fire sprinklers. The piping in such systems shall be approved for potable water. Such systems shall not have a fire department connection.
- ASSE 1024 dual check backflow preventers shall be permitted in limited area fire sprinkler systems that comply with NFPA 13 and do not have a fire department connection.
- Where fire protection systems supplied from a potable water system include a fire department connection which is located less than 1,700 feet from a non-potable water source, the water supply shall be protected by one of the following:
- Reduced pressure backflow preventer assembly; or
- Reduced pressure detector assembly.
- Where fire protection systems are filled with solutions that are considered to be health hazards as defined in Section 1.2, ASSE 1013 reduced pressure fire protection principle backflow preventers (RPF) or ASSE 1047 reduced pressure detector fire protection backflow prevention assemblies (RPDA or RPDA-II) shall be required.
- Whenever a backflow prevention assembly is installed in a potable water supply to a fire protection system, the hydraulic design of the fire protection system shall account for the pressure drop through the backflow prevention assembly.
- If a backflow prevention assembly is retrofitted for an existing fire protection system, the hydraulics of the fire protection system shall be checked to verify that there will be sufficient water pressure available for satisfactory operation of the fire protection system with the backflow prevention assembly in place.
- Potable water supplies to systems having no pumps or connections for pumping equipment, and no chemical injection or provisions for chemical injection, shall be protected from backflow by one of the following:
- Atmospheric type vacuum breaker — ASSE 1001 (for non-continuous pressure)
- Pressure vacuum breaker assembly — ASSE 1020
- Spill resistant vacuum breaker (SVB) — ASSE 1056
- Reduced pressure principle backflow preventer — ASSE 1013 (RP)
- Where lawn sprinkler and irrigation systems have pumps, connections for pumping equipment, auxiliary air tanks or are otherwise capable of creating backpressure, the potable water supply shall be protected by the following type of device if the backflow prevention device is located upstream from the source of backpressure:
- Reduced pressure principle backflow preventer — ASSE 1013 (RP)
- Where systems have a backflow preventer installed downstream from a potable water supply pump or a potable water supply pump connection, the preventer shall be one of the following:
- Atmospheric type vacuum breaker — ASSE 1001 (for non-continuous pressure)
- Pressure vacuum breaker assembly (PVB) — ASSE 1020
- Spill resistant vacuum breaker (SVB) — ASSE 1056
- Reduced pressure principle backflow preventer — ASSE 1013 (RP)
- Where systems include a chemical injector or any provisions for chemical injection, the potable water supply shall be protected by the following:
- Reduced pressure principle backflow preventer — ASSE 1013 (RP)
- Heat exchangers used for heat transfer, heat recovery, or solar heating shall protect the potable water system from being contaminated by the heat transfer medium, in accordance with either subparagraph b or c below.
- Single-wall heat exchangers shall be permitted if they satisfy all of the following requirements:
- The heat transfer medium is either potable water or contains only substances that are recognized as safe by the U.S. Food and Drug Administration.
- The pressure of the heat transfer medium is maintained less than the normal minimum operating pressure of the potable water system.
EXCEPTION: Steam complying with subparagraph b.1.
- The equipment is permanently labeled to indicate that only additives recognized as safe by the FDA shall be used in the heat transfer medium.
- Double-wall heat exchangers shall separate the potable water from the heat transfer medium by providing a space between the two walls that is vented to the atmosphere.
- Water heater and boiler drain valves that are provided with hose connection threads and that are intended only for tank or vessel draining shall not be required to be equipped with a backflow preventer.
- This section shall not apply to water supply valves intended for connection to clothes washing machines where backflow prevention is otherwise provided or is integral with the machine.
- Chemical Dispensing Systems
Chemical dispensing systems with connections to the potable water distribution system shall protect the water distribution systems from backflow in accordance with ASSE 1055 and shall have an integral means of backflow protection.In cases where an installation involves a water source coming from a faucet with an integrated vacuum breaker device conforming to ASSE 1001 or ASSE 1011, a pressure bleed device conforming to IAPMO PS-104 shall be used to prevent continuous pressure on a vacuum breaker device.
- Portable Cleaning Equipment
Where the water distribution system connects to portable cleaning equipment, the water supply system shall be protected against backflow in accordance with Section 10.5, which allows for an atmospheric vacuum breaker, pressure vacuum breaker, double check valve, or a reduced pressure principle assembly.
EXCEPTION: Atmospheric vacuum breakers shall not be used where there are shutoff valves or other shutoff devices downstream or where they are subject to continuous pressure for more than 12 hours at a time.
- Dental Pump Equipment
Where the water distribution system connects to dental pumping equipment, the water supply system shall be protected against backflow in accordance with Section 10.5, which allows for an atmospheric vacuum breaker, pressure vacuum breaker, double check valve, or a reduced pressure principle assembly.
EXCEPTION: Atmospheric vacuum breakers shall not be used where there are shutoff valves or other shutoff devices downstream or where they are subject to continuous pressure for more than 12 hours at a time.
- Water Powered Back-up Sump Pumps
- The potable water supply to water powered backup sump pumps shall be protected against backflow by an ASSE 1013 (RP) reduced pressure principle backflow preventer. Vacuum breakers shall not be permitted.
- Pump control valves, ejectors, and discharge piping shall be installed in accordance with the manufacturer's instructions.
- Laboratory Sink Faucets
Faucets on laboratory sinks shall be protected against backflow from backsiphonage and backpressure by the attachment of an ASSE 1035 laboratory faucet backflow preventer. The backflow preventer shall not be subjected to constant supply pressure and there shall be no shut-off devices downstream. The backflow preventer shall be limited to backpressure of not more than 6 inches of water elevation beyond its outlet.
- Pipe sleeves shall be provided where water service pipes penetrate foundation walls or floor slabs to protect against corrosion of the pipe and allow clearance for expansion, contraction and settlement. The sleeve shall form a watertight bond with the wall or floor slab. The annular space between the pipe and the sleeve shall be resiliently sealed watertight.
- Where water service piping is plastic, a wall sleeve shall be not less than five feet long extended outside beyond the wall to undisturbed earth or other equivalent support. See Figure 10.6.4
WATER SERVICE PIPE FOR METALLIC AND PLASTIC PIPING
- When the water pressure in the public water main or individual water supply system is insufficient to supply the potable peak demand flow to plumbing fixtures and other water needs freely and continuously with the minimum pressure and quantities specified in Section 10.14, or elsewhere in this Code, the rate of supply shall be supplemented by one of the following methods:
- An elevated water tank.
- A hydropneumatic pressure booster system.
- A water pressure booster pump.
|Table 10.8.3 |
Size of Overflow Pipes for Water Supply Tanks
|Maximum Makeup Water Flow - gpm||13||55||100||165||355||640||1040||>1040|
|Overflow Pipe Size - inches||1-1/2||2||2-1/2||3||4||5||6||8|
- Water service piping and hot and cold water distribution piping in new or renovated potable water systems shall be disinfected after flushing and prior to use.EXCEPTION: Single dwelling units with public water supply.
- The procedure used shall be as follows or an approved equivalent:
- All water outlets shall be posted to warn against use during disinfecting operations.
- Disinfecting shall be performed by persons experienced in such work.
- The water supply to the piping system or parts thereof being disinfected shall be valved-off from the normal water source to prevent the introduction of disinfecting agents into a public water supply or portions of a system that are not being disinfected.
- The piping shall be disinfected with a water-chlorine solution. During the injection of the disinfecting agent into the piping, each outlet shall be fully opened several times until a concentration of not less than 50 parts per million chlorine is present at every outlet. The solution shall be allowed to stand in the piping for at least 24 hours.
- An acceptable alternate to the 50 ppm/24-hour procedure described in Section 10.9.2.b.4 shall be to maintain a level of not less than 200 parts per million chlorine for not less than three hours. If this alternate procedure is used, the heavily concentrated chlorine shall not be allowed to stand in the piping system for more than 6 hours. Also, special procedures shall be used to dispose of the heavily concentrated chlorine in an environmentally acceptable and approved manner.
- At the end of the required retention time, the residual level of chlorine at every outlet shall be not less than five parts per million. If the residual is less than five parts per million, the disinfecting procedure shall be repeated until the required minimum chlorine residual is obtained at every outlet.
- After the required residual chlorine level is obtained at every outlet, the system shall be flushed to remove the disinfecting agent. Flushing shall continue until the chlorine level at every outlet is reduced to that of the incoming water supply.
- Any faucet aerators or screens that were removed under Section 10.9.1 shall be replaced.
- A certification of performance and laboratory test report showing the absence of coliform organisms shall be submitted to the Authority Having Jurisdiction upon satisfactory completion of the disinfecting operations.
- The building water service shall be provided with a readily accessible gate valve or other full-way shutoff valve located inside the building near the point where the water service enters. See Figure 1.2.82
- Provisions shall be made to drain the piping immediately downstream from the building valve for service or maintenance. Drains shall be capped or plugged to prevent them from being inadvertently discharged. Bleed valves shall be permitted to satisfy this requirement.
- If a building has two or more water services that are interconnected within the building, full-size check valves shall be installed near the outlets of the building valves to prevent backflow from one water service to another. Pressure test connections shall be provided on both sides of the check valves.
WATER HEATER SHUTOFF VALVE(S)
METER SHUTOFF VALVES IN A SMALL WATER SERVICE
METER SHUTOFF VALVES IN A LARGE WATER SERVICE
- In a building used or intended to be used for other than dwelling purposes, the water distribution pipe to each fixture or other piece of equipment shall be provided with a valve or fixture stop to shut off the water to the fixture or to the room in which it is located. These valves shall be accessible. Each sill cock and wall hydrant shall be separately controlled by a valve inside the building.
- Self-piercing and needle-type saddle valves shall be prohibited.
- In single dwelling units, the building valve required by Section 10.12.2 shall shutoff the water supply to all fixtures and outlets.
- In multiple dwelling units, one or more shutoff valves shall be provided in the main supply or main branches in each dwelling unit so that the water supply to any plumbing fixture or group of fixtures in that dwelling unit can be shut off without stopping the water supply to fixtures in other dwelling units. These valves shall be accessible in the dwelling unit that they control.
- Except as permitted in Section 10.12.4.d, individual fixture shutoff or stop valves shall be provided for water closets, lavatories, kitchen sinks, laundry trays, bar sinks, bidets, clothes washing machines, sill cocks, wall hydrants, appliances, and equipment connected to the water supply system. Valves for fixtures, appliances, and equipment shall be accessible without having to move the appliance or equipment.EXCEPTION: Appliances shall be permitted to be moved for access to shutoff valves for ice makers.
- Unless individual fixture shutoff valves are provided for fixtures in powder rooms or bathroom groups in accordance with Section 10.12.4.c, shutoff valves may be provided for each powder room or bathroom group in lieu of individual fixture shutoff valves. In individual dwelling units where powder rooms or bathroom groups are located adjacent to each other or one directly above the other, they may be considered as a single group and shall be permitted to have a single set of shutoff valves.
- Self-piercing and needle-type saddle valves shall be prohibited.
REQUIRED WATER SHUTOFF VALVES IN SINGLE DWELLING UNITS
REQUIRED WATER SHUTOFF VALVES IN MULTI-DWELLING UNITS
- Individual fixture supply branch pipe sizes shall be based on the minimum available flowing water pressure at its point of connection to the water distribution system, any elevation difference between that connection and the fixture, and the allowable pressure loss in the fixture supply branch. The minimum fixture supply branch pipe sizes shall be as indicated in Table 10.14.2A. For design purposes, the required pressure at each fixture inlet shall be 15 psig minimum flowing, except 20 psig minimum flowing for flushometer valves on siphon jet water closets and 25 psig minimum flowing for flushometer valves on blowout water closets and blowout urinals. Flushometer tank (pressure assisted) water closets require a minimum of 25 psig static pressure. The following water flow rates shall be used for the purpose of sizing individual fixture supply branch pipes:5.0 gpm for hose bibbs and wall hydrants;
4.0 gpm for bath faucets and clothes washers;
0.75 gpm for drinking fountains and water coolers;
2.2 gpm for sink faucets;
2.5 gpm for shower heads;
2.2 gpm for lavatory faucets;
3.0 gpm for water closets other than the flushometer valve type;
12.0 gpm for flushometer valve urinals;
30.0 gpm for flushometer valve water closets
- Fixture supply branches shall extend from the distribution system to within 30 inches of the point of connection to the fixture or device served and be within the same area and physical space as the point of connection to the fixture or device. Fixture supply tubes and flexible water connectors shall be not less than the size recommended by the manufacturer of the fixture, faucet, appliance or device served.
WATER SUPPLY FIXTURE UNITS (WSFU) AND MINIMUM FIXTURE SUPPLY BRANCH PIPE SIZES
HEAVY-USE ASSEMBLY OTHER THAN DWELLING UNITS SERVING 3 OR MORE DWELLING UNITS INDIVIDUAL DWELLING UNITS MINIMUM SUPPLY BRANCH PIPE SIZE BATHROOM GROUPS HAVING 1.6 GPF WATER CLOSETS OTHER THAN THE FLUSHOMETER TYPE Half-Bath or Powder Room 3.5 2.5 1 Bathroom Group 5.0 3.5 1-1/2 Bathroom Groups 6.0 4.0 2 Bathroom Groups 7.0 4.5 2-1/2 Bathroom Groups 8.0 5.0 3 Bathroom Groups 9.0 5.5 Each Additional Half-Bath 0.5 0.5 Each Additional Bathroom Group 1.0 1.0 BATHROOM GROUPS HAVING 3.5 GPF (or higher) GRAVITY TANK WATER CLOSETS Half-Bath or Powder Room 4.0 3.0 1 Bathroom Group 6.0 5.0 1-1/2 Bathroom Groups 8.0 5.5 2 Bathroom Groups 10.0 6.0 2-1/2 Bathroom Groups 11.0 6.5 3 Bathroom Groups 12.0 7.0 Each Additional Half-Bath 0.5 0.5 Each Additional Bathroom Group 1.0 1.0 OTHER GROUPS OF FIXTURES Bathroom Group with 1.6 GPF Flushometer Valve 6.0 4.0 Bathroom Group with 3.5 GPF (or higher) Flushometer Valve 8.0 6.0 Kitchen Group with Sink and Dishwasher 2.0 1.5 Laundry Group with Sink and Clothes Washer 5.0 3.0 INDIVIDUAL FIXTURES Bar Sink 3/8" 1.0 0.5 Bathtub or Combination Bath/Showcr 1/2" 4.0 3.5 Bidet 1/2" 1.0 0.5 Clothes Washer, Domestic 1/2" 4.0 2.5 4.0 Dishwasher, Domestic 1/2" 1.5 1.0 1.5 Drinking Fountain or Water Cooler 3/8" 0.5 0.75 Hose Bibb (first) 1/2" 2.5 2.5 2.5 Hose Bibb (each additional) 1/2" 1.0 1.0 1.0 Kitchen Sink, Domestic 1/2" 1.5 1.0 1.5 Laundry Sink 1/2" 2.0 1.0 2.0 Lavatory 3/8" 1.0 0.5 1.0 1.0 Service Sink or Mop Basin 1/2" 3.0 Shower 1/2" 2.0 2.0 2.0 Shower, continuous use 1/2" 5.0 Urinal, 1.0 GPF 3/4" 4.0 5.0 Urinal, greater than 1.0 GPF 3/4" 5.0 6.0 Wash Fountain (per rated user) 0.5 Wash Sink (1 or 2 faucets, per faucet) 1.0 Wash Sink (additional faucets, per faucet) 0.5 Water Closet, 1.6 GPF Gravity Tank 1/2" 2.5 2.5 2.5 4.0 Water Closet, 1.6 GPF Flushometer Tank 1/2" 2.5 2.5 2.5 3.5 Water Closet, 1.6 GPF Flushometer Valve 1" 5.0 5.0 5.0 8.0 Water Closet, 3.5 GPF Gravity Tank 1/2" 3.0 3.0 5.5 7.0 Water Closet, 3.5 GPF Flushometer Valve 1" 7.0 7.0 8.0 10.0 Whirlpool Bath or Combination Bath/Showcr 1/2" 4.0 4.0NOTES FOR TABLE 10.14.2A:
- A Bathroom Group, for the purposes of this Table, consists of not more than one water closet, up to two lavatories, and either one bathtub, one bath/shower combination, or one shower stall. Other fixtures within the bathing facility shall be counted separately to determine the total water supply fixture unit load.
- A Half-Bath or Powder Room, for the purposes of this Table, consists of one water closet and one lavatory.
- For unlisted fixtures, refer to a listed fixture having a similar flow and frequency of use.
- The listed fixture unit values for Bathroom Groups and Individual Fixtures represent their load on the cold water service. The separate cold water and hot water fixture unit values for fixtures having both cold and hot water connections shall each be taken as 3/4 of the listed total value for the individual fixture.
- When WSFU values are added to determine the demand on the water distribution system or portions thereof, round the sum to the nearest whole number before referring to Table 10.14.2B for the corresponding gallons per minute (gpm) flow. WSFU values of 0.5 or more should be rounded up to the next higher whole number (9.5 = 10 WSFU). Values of 0.4 or less should be rounded down to the next lower whole number (9.4 = 9 WSFU).
- The listed minimum supply branch pipe sizes for individual fixtures are the nominal (I.D.) pipe size in inches.
- "Other Than Dwelling Units" applies to business, commercial, industrial, and assembly occupancies other than those defined under "Heavy-Use Assembly." Included are the public and common areas in hotels, motels and multi-dwelling buildings.
- "Heavy-Use Assembly" applies to toilet facilities in occupancies that place heavy, but intermittent, time-based demands on the water supply system, such as schools, auditoriums, stadiums, race courses, transportation terminals, theaters, and similar occupancies where queuing is likely to occur during periods of peak use.
- For fixtures or supply connections likely to impose continuous flow demands, determine their required flow in gallons per minute (gpm) and add it separately to the demand (in gpm) for the distribution system or portion thereof.
TABLE FOR CONVERTING DEMAND IN WSFU TO GPM1
WSFU GPM Flush Tanks2 GPM Flush Valves3 WSFU GPM Flush Tanks2 GPM Flush Valves3 3 3 120 49 74 4 4 140 53 78 5 4.5 22 160 57 83 6 5 23 180 61 87 7 6 24 200 65 91 8 7 25 225 70 95 9 7.5 26 250 75 100 10 8 27 300 85 110 11 8.5 28 400 105 125 12 9 29 500 125 140 13 10 29.5 750 170 175 14 10.5 30 1000 210 210 15 11 31 1250 240 240 16 12 32 1500 270 270 17 12.5 33 1750 300 300 18 13 33.5 2000 325 325 19 13.5 34 2500 380 380 20 14 35 3000 435 435 25 17 38 4000 525 525 30 20 41 5000 600 600 40 25 47 6000 650 650 50 29 51 7000 700 700 60 33 55 8000 730 730 80 39 62 9000 760 760 100 44 68 10,000 790 790NOTES FOR TABLE 10.14.2B:
- This table converts water supply demands in water supply fixture units (WSFU) to required water flow in gallons per minute (GPM) for the purpose of pipe sizing.
- This column applies to portions of piping systems where the water closets are the flush tank type (gravity or pressure) or there are no water closets, and to hot water piping.
- This column applies to portions of piping systems where the water closets are the flush valve type.
- Refer to Appendix K for WSFU values that are interpolated between the values listed in Table 10.14.2B to the degree that the WSFU increments are close enough that they do not produce GPM differences that would be significant in sizing water supply distribution piping.
- The supply demand in gallons per minute in the building hot and cold water distribution system shall be determined on the basis of the load in terms of water supply fixture units (WSFU) as shown in Table 10.14.2A and the relationship between the load in WSFU and the supply demand in gallons per minute (GPM) as shown in Table 10.14.2B. Refer to Appendix M for a more detailed table of WSFU and equivalent GPM. For fixtures having both hot water and cold water connections, the separate hot and cold water loads shall be taken as 75% of the listed WSFU value.
- Main risers and branches of the water distribution system shall be sized based on the minimum available water pressure at the source, any elevation differences between the source and the fixtures, pressure losses in the distribution system, and the pressure (with flow) required at each connection to the fixture supply branches. See Section 10.14.2.
- Pressure reducing valves complying with ASSE 1003 shall be provided if required to limit the water supply pressure at any fixture, appliance, appurtenance, or outlet to not more than 80 psi under no-flow conditions.
- The requirement of Section 10.14.6.a above shall not prohibit supply pressures higher than 80 psi from water pressure booster systems under Section 10.14.4 or in high pressure distribution systems, provided that the pressure at the fixtures served is subsequently reduced to 80 psi maximum. Where operating water pressures exceed 80 psi, the working pressure rating of materials and equipment shall be suitable for the maximum pressure that may be encountered, including temporary increases or surges.
- Where pressure reducing valves are installed and the downstream piping is not rated for the maximum upstream pressure, a pressure relief valve shall be installed downstream from the pressure reducing valve. The relief valve shall be set not higher than the working pressure rating of the downstream piping and sized for not less than the flow capacity of the pressure reducing valve. Relief valves shall discharge in accordance with Section 10.16.6.
- When a pressure reducing valve is installed, a gauge port or pressure gauge with pressure range of 0-150 psi shall be installed within 24 inches downstream from the reducing valve.
INSTALLATION OF A WATER PRESSURE REDUCING VALVE WHERE THE WATER SUPPLY PRESSURE EXCEEDS 80 PSIG
ONE POSSIBLE ARRANGEMENT OF PRESSURE REDUCING VALVES IN A HIGH-RISE BUILDING
- Approved water hammer arresters, complying with ASSE 1010 or PDI WH 201 shall be installed on water distribution piping in which quick closing valves are installed.EXCEPTION: Single lever faucets, domestic clothes washers, and domestic dishwashers.
- Water hammer arresters shall be placed as close as possible to the quick acting valve, at the end of long piping runs, or near batteries of fixtures.
- Arresters shall be accessible for replacement.
WATER HAMMER ARRESTORS
- Where the developed length of the hot water supply piping to any hot water outlet exceeds 100 feet from the hot water source, the system shall maintain the temperature of the hot water to within 25 feet of that outlet.
- Where hot water temperature maintenance is required by Section 10.15.2.1.a, the hot water temperature within the piping shall be maintained by recirculation or heat tracing of the hot water piping. The temperature of the hot water in the piping shall be maintained by automatic controls with manual auto-off.
- Hot water temperature maintenance controls in facilities having unoccupied periods shall be adjustable to operate only during occupied periods.
- Recirculated hot water maintenance systems shall include the necessary circulators and controls.
- Recirculated hot water shall be returned to the hot water source through dedicated hot water return piping. Return piping shall have means of adjusting the water flow rate in each of its branches.EXCEPTION: A demand-controlled pumping device serving an individual plumbing fixture shall be permitted to return water to that fixture's cold water supply until hot water at approximately 104 deg. F reaches the fixture and the demand cycle automatically ends, stopping the pump.
- Demand-controlled pumps for individual fixtures shall be started manually by a pushbutton or local light switch or automatically by a motion detector.
- Electric resistance trace heating cables shall be the self-regulating type and installed in accordance with the manufacturer's instructions.
- The hot water pipe material shall be suitable for the installation of the electric trace heating cables, as indicated by the cable manufacturer.
- Electric resistance trace heating systems shall comply with IEEE 515 (industrial), IEEE 515.1 (commercial), or UL 515 (commercial).
- Electric heat traced piping shall be labeled as "ELECTRIC TRACED" at 10-foot maximum spacing.
HOT WATER TEMPERATURE MAINTAINENCE BY RECIRCULATION
- Hot water storage tanks shall be adequate in size, when combined with the capacity of the water heating equipment, to provide sufficient hot water for both the hourly peak loads and daily requirements of the occupancy served.
- Pressure tanks shall comply with the design and construction requirements of Section 3.3.8.
- Safety devices for pressure tanks shall comply with Section 3.3.10.
- Hot Water Supply Sources: The temperature control devices for water heaters and other hot water supply sources shall not be permitted to be used to meet this Section's requirements for mixed water temperature control.
- Hot Water Distribution Temperature Control: Where temperature-actuated mixing valves are installed to control the hot water supply temperature in the water distribution system, they shall comply with ASSE 1017. Such devices shall be installed at the hot water source and alone shall not supersede the other requirements of Section 10.15.6 for mixed water temperature control.
- Application of Water Temperature Control and Limiting Devices: The inlet hot and cold water temperatures for temperature control and limiting devices shall be within their operating ranges and have sufficient differential above and below their discharge set point.
- Where Check Valves Are Required: Where a water temperature control or temperature limiting device supplies one or more outlets that can be shutoff downstream from the device, the device shall include integral check valves or check valves shall be provided in the hot and cold water supplies to the device or at its inlets to prevent cross flow through the device when there is no flow through the outlet or outlets that it supplies.
- Showers and Bath/Shower Combinations: The water discharged from shower heads, wall or ceiling mounted hand-held showers, body sprays, and tub spouts shall be controlled to a temperature no higher than 120°F by a Type P, Type T, or Type P/T automatic compensating valve complying with ASSE 1016/ASME A112.1016/CSA B125.16.
- Multiple Showers: Where multiple (gang) showers are supplied by a one-pipe tempered water supply system, the water temperature shall be controlled to a temperature no higher than 105°F by an automatic temperature control mixing valve complying with ASSE 1069.
- Multiple Lavatories: Where multiple lavatories are supplied by a one-pipe tempered water supply system, the water temperature shall be controlled to a temperature no higher than 110°F by a water temperature limiting device complying with ASSE 1070/ASME A112.1070/CSA B125.70.
- Bathtubs and Whirlpool Baths: The hot water supply to the faucets for bathtubs and whirlpool baths without showers and with or without deck-mounted hand sprays, shall be controlled to a temperature no higher than 120°F by a water temperature limiting device complying with ASSE 1070/ASME A112.1070/CSA B125.70.EXCEPTION: A water temperature limiting device shall not be required if the fixture is supplied by an ASSE 1016/ASME A112.1016/CSA B125.16 automatic compensating valve.
- Bidets: The hot water supply to the faucet on bidet plumbing fixtures shall be controlled to a temperature no higher than 110°F by a water temperature limiting device complying with ASSE 1070/ASME A112.1070/CSA B125.70. Where bidets are incorporated into toilet seats or consist of a heated water tank and nozzle, their controls shall limit the discharge temperature to no more than 110°F.
- Hand Washing Facilities: The hot water supply to the following hand washing fixtures shall be controlled to a temperature no higher than 110°F by a water temperature limiting device complying with ASSE 1070/ASME A112.1070/CSA B125.70:
- in public toilet rooms
- in hotel and motel guest rooms
- in hospital patient rooms
- in medical and clinical treatment rooms
- wash fountains
- wash sinks
- Commercial Hair/Shampoo Sink Sprays: The hot water supply to the faucets and controls for commercial hair/shampoo sink sprays and pedicure basins shall be limited to a temperature no higher than 110°F by a temperature limiting device complying with ASSE 1070/ASME A112.1070/CSA B125.70.
- Animal Washing Fixtures: The hot water supply to the faucet or control device for an animal washing fixture shall be controlled to a temperature no higher than 110°F by a temperature limiting device complying with ASSE 1070/ASME A112.1070/CSA B125.70.
- Temperature Actuated Flow Reduction (TAFR) Valves: Temperature actuated flow reduction (TAFR) valves that limit the maximum mixed water temperature to 120°F for individual fixture fittings shall comply with ASSE 1062. The installation of TAFR valves shall not supersede the other requirements of Section 10.15.6 for mixed water temperature control.
- In-Line Pressure Balancing Valves: Where in-line pressure balancing valves are installed to compensate for water pressure fluctuations to stabilize the temperature discharges from their individual faucet or fixture fitting, such devices shall comply with ASSE 1066. These devices shall be installed in an accessible location and alone shall not supersede the other requirements of Section 10.15.6.
- Devices installed for mixed water temperature control, temperature limiting, flow reduction, or pressure balance shall be field-adjusted in accordance with the manufacturer's instructions.
- Where a water pressure regulator (with or without an internal thermal expansion bypass), a backflow preventer, or a check valve is installed such that a closed system is created, a thermal expansion tank shall be provided.EXCEPTIONS: (1) Instantaneous water heaters. (2) Well systems with water pressure tanks that are open to flow of thermal expansion from the water heating equipment.
- Thermal expansion tanks shall be the adjustable pre-charged type for potable hot water, steel construction with a flexible bladder or bellows, rated for not less than 125 psig and 200°F, and sized to limit the increased water system pressure to no higher than 100 psig. Tanks shall be sized, installed, and adjusted in accordance with the manufacturer's instructions and shall be supported independent from the connected piping.
- Thermal expansion tanks shall be connected to the cold water supply piping for the hot water heating equipment, between the heating equipment and its cold water shutoff valve.
- Expansion tanks used in conjunction with ASME HLW water heaters shall be constructed and certified to the ASME Boiler and Pressure Vessel Code, Section VIII.
- Plastic piping used for hot water distribution shall conform to the requirements of Section 3.4.3 and Table 3.4.3. Piping shall be water pressure rated for not less than 100 psi at 180°F and 160 psi at 73°F.NOTE: The working pressure rating for certain approved plastic piping materials varies depending on material composition, pipe size, wall thickness and method of joining. See Table 3.4.3.
- Plastic pipe or tube shall not be used downstream from instantaneous water heaters, immersion water heaters or other heaters not having approved temperature safety devices.
- Piping within six inches of flue or vent connectors shall be approved metallic pipe or tube.
- The normal operating pressure in water distribution piping systems utilizing approved plastic pipe or tube for hot water distribution shall be not more than 80 psi. Where necessary, one or more pressure reducing valves shall be provided to regulate the hot and cold water supply pressure to not more than 80 psi.
- The pressure in the hot water distribution piping shall be limited by a pressure relief valve set no higher than 150 psi. When the water heater is protected by a pressure relief valve or combination pressure temperature relief valve having a pressure setting higher than 150 psi, a separate pressure relief valve shall be provided to protect the piping. The relief valve for the piping shall comply with Section 10.16.2 except that it shall be set no higher than 150 psi. Thermal expansion shall be controlled as required under Section 10.15.7.
- Drip pans shall be watertight and constructed of corrosion-resistant materials. Galvanized steel pans shall be 24 gauge (0.0276-inch) minimum thickness. Aluminum pans shall be 20 gauge (0.0320-inch) minimum thickness. Non-metallic pans shall be 0.0625-inch minimum thickness. Pans shall be not less than 1-1/2" deep but shall not be deeper than the bottom of the water heater tank or hot water storage tank. They shall be of sufficient size to hold the heater or tank without interfering with drain valves, burners, controls, and any required access.
- High impact plastic pans shall be permitted under gas-fired water heaters where the heater is listed for zero clearance for combustible floors and the application is recommended by the pan manufacturer.
- Drip pans shall have drain outlets not less than 3/4" size, with drain pipes extending to an approved point of discharge, a suitably located indirect waste receptor, or to within 2 to 6 inches above the adjacent floor.
- Discharge from a relief valve into a water heater drip pan shall be permitted if the drain size for the drip pan is not less than the relief valve discharge pipe size and the discharge pipe extends to within 2 to 6 inches above the bottom of the pan.
- For drip pans installed under water heaters that are located above ceilings, the drain pipe from the drip pan shall extend to a point of disposal or indirect waste that is readily observable in an area below the heater.
- Water heaters shall be applied, sized, and installed in accordance with the manufacturer's recommendations and instructions.
- Gas-fired storage tank water heaters with input ratings of 75,000 Btuh or less shall comply with ANSI Z21.10.1/CSA 4.1.
- Gas-fired storage tank water heaters with input ratings above 75,000 Btuh shall comply with ANSI Z21.10.3/CSA 4.3.
- Gas-fired tankless water heaters shall comply with ANSI Z21.10.3/CSA 4.3.
- Oil-fired storage tank water heaters shall comply with UL 732.
- Household electric storage tank water heaters up to 120 gallons and 12 KW capacity shall comply with UL 174.
- Commercial electric storage tank water heaters over 120 gallons and 12 KW capacity shall comply with UL 1453.
- Tankless electric water heaters shall comply with UL 499.
- Heat pump water heaters shall comply with UL 60335-2-40.
- Combination water heaters used for domestic water and space heating shall be designed and certified for such use.
- Water piping connected to a combination water heater for space heating shall be suitable for use with potable water.
- An ASSE 1017 temperature actuated mixing valve shall be installed in the domestic hot water outlet piping at a combination water heater to limit the domestic hot water supply temperature to 140°F maximum for the distribution system.
- The water heating units shall comply with the applicable requirements of ANSI Z21.10.1/CSA 4.1, ANSI Z21.10.3/CSA 4.3, ASME BPVC-I , ASME BPVC-IV, ASME CSD-1, UL 174, UL 499, UL 726, UL 732, UL 834, and UL 1453.
- Pressure vessels used for heating water or storing heated water at pressures above atmospheric shall be protected by approved safety devices in accordance with one of the following methods:
- A separate pressure relief valve and a separate temperature relief valve; or
- A combination pressure and temperature relief valve; or
- Either "1" or "2" above and an energy cut-off device.
- Tank construction conforming to a standard that does not require a temperature or pressure safety or relief valve.
- Pressure relief valves shall comply with the applicable standards listed in Table 3.1.3.
- The valves shall have a relief setting of not more than the pressure rating of the tank, or 150 psig maximum, and shall be installed either directly in a tank tapping or in the hot or cold water piping close to the tank. Pressure relief valves installed in hot water piping shall be rated for not less than 180°F.
- There shall be no shutoff valve between the pressure relief valve and the tank.
- The pressure relief valve shall be set to open at not less than 25 psig above the street main pressure or not less than 25 psig above the setting of any building water pressure regulating valve.
- Temperature relief valves shall have an adequate relief rating, expressed in BTU/HR, for the equipment served.
- The CSA temperature steam rating shall be used when a water heater has a heat input rating of 200,000 BTU/HR or less, a water temperature of 210°F or less, a nominal water-containing capacity of 120 gallons or less, is not ASME rated, and does not exhibit an ASME "HLW" symbol or a National Board "NB" number.
- The ASME pressure steam rating shall be used if a water heater is ASME rated and exhibits an ASME "HLW" symbol or a National Board "NB" number.
- The valves shall be installed so that the temperature sensing element is in the hottest water within the top 6 inches of the tank.
- The valves shall be set to open when the stored water temperature reaches a maximum of 210°F. (See Section 3.3.10.)
- The valves shall conform to an approved standard and shall be sized so that when the valve opens, the water temperature cannot exceed 210°F with the water heating equipment operating at maximum input.
- There shall be no shutoff valve, check valve, or other restricting device between a relief valve and the pressure vessel or piping system being protected.
- Piping from the outlet of a relief valve to the point of disposal shall be of a material suitable for potable water (see Section 3.4). Discharge pipes from temperature relief valves and combination pressure-temperature relief valves shall be listed in Table 3.4 for hot water distribution, and shall be suitable for conveying water at 210°F to an open discharge. The pressure rating of the pipe at 210°F is not required to equal or exceed the pressure setting of the relief valve.
- The discharge pipe shall be no smaller than the outlet size of its relief valve and shall extend to a point of disposal without valves, traps, or rises that would prevent the discharge piping from draining by gravity. The discharge end of the pipe shall not be threaded.
- A visible air gap shall be provided where relief valves discharge into an indirect waste pipe, floor drain, trench drain, service sink, mop basin, laundry sink, standpipe, or other approved receptor. The minimum size of fixture drains or waste pipes that receive the discharge from relief valves shall be as indicated in Table 10.16.6.
- Where relief valves discharge to the floor, the discharge pipe shall terminate not more than 6 inches nor less than 2 inches above the floor.
- If the point of discharge is not within the space or room in which the relief valve is located, an indirect gravity drain shall be provided from the room or space to the point of disposal. Indirect waste pipes shall be sized according to Table 10.16.6 and shall be of a material approved for potable water, sanitary drainage, or storm drainage (see Tables 3.4, 3.5, and 3.7). A visible air gap shall be provided in the room or space in which the relief valve is located.
- Where water heaters are located above ceilings, the relief valve discharge pipe shall extend to a point of disposal or indirect waste that is readily observable in an area below the heater.
- Where two or more relief valves serving independent systems are located in the same area, each shall be discharged separately.
WATER HEATER RELIEF VALVES AND DISCHARGE PIPING
|Table 10.16.6 |
SIZE OF DRAINS OR WASTE PIPES RECEIVING RELIEF VALVE DISCHARGE
|Discharge Pipe Size||Minimum Drain or Indirect Waste Size|
|*EXCEPTION: A laundry sink with 1-1/2" waste pipe|
- Where water distribution piping can siphon water from a water heater and cause dry-firing, a vacuum relief valve shall be installed on the cold water inlet piping to the water heater.
- Vacuum relief valves shall comply with ANSI Z21.22/CSA 4.4 and be rated for not less than 210°F.
- Vacuum relief valves shall be installed at an elevation above the top of the heater tank, downstream of the shutoff valve.
- Vacuum relief valves shall be installed in the vertical, upright position unless otherwise permitted by the manufacturer's instructions.
- Vacuum relief valves size shall be 3/4" minimum nominal pipe size.
VACUUM RELIEF VALVES ON OVERHEAD WATER HEATER TANKS
- Relief valves shall be maintained in proper working order and shall be replaced when necessary.
- Whenever a water heater is replaced, its temperature relief valve and pressure relief valve, or combination temperature-pressure relief valve, and its vacuum relief valve (if installed) shall also be replaced and shall not be reused.
- Parallel water distribution systems shall provide individual hot and cold water supply lines from a manifold to each fixture served.
- Manifolds shall be specifically designed and manufactured for parallel water distribution.
- Manufacturers of such systems shall provide complete sizing and installations instructions, including any limitations or restrictions on use.
- Piping materials shall be as recommended by the system manufacturer and be listed in Table 3.4 for hot and cold water distribution.
- Each manifold outlet that is equipped with a shutoff valve shall identify the fixture being supplied. Additional shutoff or stop valves at the fixtures shall be provided as required by Section 10.12.4.EXCEPTION: Additional shutoff or stop valves at the fixtures shall not be required if a manifold with shutoff valves is located within the same room as the fixtures, or in an adjacent closet.
- Manifolds having shutoff valves shall be readily accessible.
- Tube bundles for manifold systems shall be supported in accordance with Chapter 8 of this Code.
- Supports at changes in direction shall be in accordance with the system manufacturer's recommendations.
- NSF 42 Drinking Water Treatment Units - Aesthetic Effects
- NSF 44 Water Softeners (cation exchange)
- NSF 53 Drinking Water Treatment Units - Health Effects
- NSF 55 Ultraviolet Microbiological Water Treatment Systems
- NSF 58 Reverse Osmosis Drinking Water Systems
- CSA B483.1 Drinking Water Treatment Systems
|Table 10.19 |
SIZING OF RESIDENTIAL WATER SOFTENERS
|Required Size of Softener Connection (in.)||Number of Bathroom Groups Served1|
|3/4||Up to 22|
|1||Up to 43|
- The number of bathroom groups served may include a kitchen sink, dishwasher, laundry sink, and automatic clothes washer.
- An additional water closet and lavatory shall be permitted without an increase in sizing.
- Over four Bathroom Groups, the softener shall be engineered for the specific installation.
- Where non-potable water distribution systems are installed for irrigation, flushing water closets or urinals, or other non-potable water use in typical potable water applications, the following shall apply:
- The use of non-potable water shall be approved by the Authority Having Jurisdiction.
- The piping shall comply with Section 3.4 for potable water.
- Non-potable water piping shall be visibly identified to differentiate it from potable water piping.
- Non-potable water pipe may be purple colored.
- Potable water pipe shall not be purple colored.
- Non-potable water piping shall be identified by distinctive labels marked NON-POTABLE WATER that comply with ASME A13.1 and have a safety purple background color and white letter color. One or more labels shall be visible from all points of observation. Piping that passes through walls shall be labeled on both sides of the wall. Where piping is concealed within ceilings, walls, or other construction, at least one label shall be visible from any possible point of access, including penetration of the concealment. The labeling on piping that will be concealed shall be inspected prior to being concealed.
- Each outlet from a non-potable water piping system that could be mistakenly used for drinking, culinary uses, or domestic purposes shall be posted as follows:
DANGER (red background) - UNSAFE WATER - DO NOT DRINK