Washington plumbing code pdf

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Code diagrams: Unpack the code through illustrations and descriptions. Features Overview. A reliable and up-to-date source of codes. Rapidly and efficiently calculate project parameters. No strain shall be transmitted to the connecting piping. Fastening screws or bolts shall be corrosion-resisting. In addition to the wall support brackets, pedestals or legs may provide additional support for pedestal lavatories. Such access is not required for connections that are sol- dered, threaded, solvent cemented, or equivalently secured.

Waterless non-water urinals shall have a liquid trap seal as required by Section 5. Lavatories shall comply with the following standards: 1. Except as required under Section 7. Public lavatory faucets, other than the metering type, shall be designed and manufactured according to ASME A Metering faucets shall deliver not more than 0. A strainer, pop-up stopper, crossbar grid, or other device shall be provided to protect the waste outlet.

Bathtubs shall comply with the following standards: 1. Waste outlets shall be equipped with a pop-up waste, chain and stopper, or other type of drain plug. Surrounding wall construction shall be in accordance with Section 7. Riser pipes to shower heads shall be secured in accordance with Section 7.

The provisions for wet vent- ing in Section The minimum outside rough-in dimension for shower bases and prefabricated shower compartments shall be 32 inches, except where a shower receptor has a minimum overall dimension of 30 inches mm in width and 60 inches 1, mm in length. The walls in shower compartments and above built-in bathtubs having installed shower heads shall be constructed of smooth.

Manufactured shower pans, shower bases, and shower receptors shall be installed in accordance with this Code and the manufacturer's instructions. Sinks shall comply with the following standards: 1. Each compartment in a kitchen sink or bar sink shall have an outlet suitable for either a domestic food waste grinder or a basket strainer. Service sinks and mop receptors shall have removable strainers and waste outlet connections not less than 2" nominal size. Weep hole drains that form a cross connection between ground water and the potable water supply shall not be permitted.

Such units may connect to a kitchen sink drain outlet, as permitted under Section 7. The water supply to dish- washing machines shall be protected from back-siphonage by an integral air gap or other internal means.

The discharge line from the dishwasher shall be not less than the size recommended by the dishwasher manufacturer. The discharge may also drain indirectly into a trapped standpipe, or receptor. Commercial dishwashing machines shall be indirectly connected to the drainage system through either an air gap or an air break.

Commercial dishwashers shall be permitted to discharge through a grease interceptor in accordance with Section 6. Where traps are automatically primed, the priming connection shall be above the weir of the trap. Floor drains shall be not less than 2" nominal size.

Floor drains shall be installed in the following areas: 1. Toilet rooms containing either two or more water closets or wall hung urinals or a combination of one or more water closets and wall hung urinals, except in a dwelling unit. Commercial kitchens. Common laundry rooms in commercial buildings and buildings having more than two dwelling units.

The water supply connection shall be protected from back-siphonage in accordance with Chapter Examples of such special installations include decorative fountains, ornamental pools, waterfalls, swimming and wading pools, baptisteries, and similar custom-built equipment. Ballcocks shall be the anti-siphon type and comply with ASSE Flushometer valves shall be accessible for maintenance and repair. Water closets shall be the elongated type with integral or separate seats.

Plans for plumbing systems, where required, shall indicate the maximum number of persons to be served by the facilities.

In occupancies having established seating, such as auditoriums and restaurants, the number of occupants for plumbing purposes shall not be less than the number of seats. The lavatories required by Tables 7. Separate toilet facilities shall be provided for each sex.

Residential installations. In occupancies serving 15 or fewer people, one toilet facility, designed for use by no more than one person at a time, shall be permitted for use by both sexes. Drinking Water Facilities: A kitchen or bar sink shall be considered as meeting the requirements for drinking water facilities for employees.

Laundry Trays: Multiple dwelling units or boarding houses without public laundry rooms shall not require laundry trays. Service Sinks: Service sinks may be omitted when the Authority Having Jurisdiction determines that they are not necessary for proper cleaning of the facility. Types of occupancies not shown in Table 7. Where swimming pools operated by an apartment building, condominium, or similar multi-family dwelling unit are restricted to the use of residents and guests of residents of dwelling units in the immedi- ate vicinity of the pool, the minimum required toilet facilities for bathers within the pool compound shall be one 1 male toilet room and one 1 female toilet room, each consisting of a water closet and lavatory as a minimum.

Requirements for customers and employees shall be permitted to be met with a single set of restrooms accessible to both groups. Fixtures for customer use shall be permitted to be met by providing a centrally located facility accessible to several stores. The maximum distance of entry from any store to this facility shall not exceed feet. The maxi- mum distance of entry from any store to this facility shall not exceed feet. Drinking water facilities are not required for customers where normal occupancy is short term.

Food service establishments with an occupant load of or more customers shall be provided with separate toilet facilities for employees and customers. Customer and employee toilet facilities may be combined for customer loads of or less.

For employees of 15 or less, one toilet facility, designed for use by no more than one person at a time, shall be permitted for use by both sexes. Drinking water facilities are not required in restaurants or other food service establishments if drinking water service is provided. Waste discharge from such equipment shall enter the drainage system through an air gap. Types of entrapment can include, but not be limited to, rigid, non-giving protrusions, wedge-shaped openings, and any arrangement of components that could pinch and entrap the user.

The suction inlets shall be piped so that water is drawn through the inlets simultaneously by a common suction line to the pump. Blocking one suction inlet shall not create excessive suction at other suction inlets. The equipment installer shall assemble and install the equipment in accordance with the manufacturer's instructions. See Notes: 4, 14,16 b Prisons, jails and reformatories long term. Moderated hazard. For accessible requirements, see local, state, or national codes. Drinking fountains are not required in restaurants or other food service establishments if drinking water service is available.

Drinking water is not required for customers where normal occupancy is short term. A kitchen or bar sink may be used for employee water drinking facilities. Fixtures for public use as required by this section may be met by providing a centrally located facility accessible to several stores.

The maximum distance from entry to any store to this facility shall not exceed feet. The maximum distance from entry to any store from this facility shall not exceed feet.

Multiple dwellings or boarding houses without public laundry rooms shall not require laundry trays. Reserved Requirements for employees and customers may be met with a single set of restrooms. If the design number of customers in food handling establishments exceeds , separate facilities for employees and customers are required.

All showers and lavatories shall have thermostatic control and timing devices. Laboratories in higher education facilities shall have safety showers.

Warehouse storage area requirements shall be permitted to be met by providing a facility centrally located within the storage area. The maximum travel distance to the facility shall not exceed feet. Showers may be omitted in recreational facilities without locker rooms when approved by the Authority Having Jurisdiction. Fixtures, appliances and equipment shall be connected to support the weight of the device and any ad- ditional probable loads that may impact on the device.

Fixtures shall be rigidly supported so that no strain is transmitted in the piping connections. Cast-iron soil pipe—at base and at each story height. Steel threaded pipe—at every other story height. Copper tube—at each story height but not more than foot intervals.

Lead pipe—four-foot intervals. Plastic pipe—see Section 8. Flexible plastic tubing—each story height and at mid-story. Stainless steel drainage pipe—at each story height. Cast-iron soil pipe—minimum of one hanger per pipe length located within 18 inches of each joint up to foot maximum pipe length , at changes in direction, and at branch connections. Where pipe is sus- pended by non-rigid hangers more than 18 inches long, provide lateral support at foot maximum spacing.

Lateral support shall consist of either 1 a sway brace or 2 either a change in direction or a branch connec- tion that provides the required lateral support. One-inch size and larger—foot intervals. Lead pipe—on continuous metal or wood strips for its entire length. Flexible plastic tubing—32 inches.

Stainless steel drainage pipe—10 foot intervals, changes of direction and branch connections. Piers shall be of concrete, brick, or other masonry construction. Provision shall be made for expansion and contraction of the piping. See Sections 4. Other piping mate- rial shall be so anchored as to support the stack at the base. Plastic drain, waste, vent, and pressure pipe shall be installed and supported as recommended by the manufacturer's instructions.

Maximum horizontal support spacing shall be based on the pipe schedule or wall thickness, the pipe size, the system operating temperature, the ambient temperature, and any concentrated loads. Vertical pipe shall be maintained in straight alignment. Intermediate supports shall be provided where required for stability. Pipe shall also be supported at changes of direction or elevation. Supports shall not compress, distort, cut, or abrade the piping and shall allow free movement.

Provisions shall be made for expansion and contraction of the piping. Fixture trap arms longer than three feet shall be supported as close as possible to the trap. The spacing for vent piping shall be permitted to be based on vapor service.

Such drains shall discharge sepa- rately through an air gap or, where permitted, an air break. Fixtures and appliances used for the storage, processing, preparation, serving, dispensing, or sale of food shall be drained indirectly.

Where bar sinks, glass-washing sinks, or other counter sinks cannot be vented according to the requirements of Chapter 12, they shall be permitted to each discharge separately to a trapped and vented receptor through indirect waste pipes providing either an air break or an air gap. Traps shall be provided in the indirect waste pipe when required under Section 9.

The above requirements do not apply to refrigerated food preparation areas or work rooms. Where necessary, cleanouts shall be provided in accordance with Section 5. Air conditioning condensate. Automatic clothes washer. Water treatment unit. Water heater relief valve discharge. In a dwelling, a laun- dry sink shall be permitted to drain into the standpipe.

The minimum drain pipe size for an indirect waste receptor shall be at least one pipe size larger than the indirect waste pipe that it serves. The nature of the corrosive or harmful waste and proposed method of its treatment shall be submitted to and approved by the Authority Having Jurisdiction prior to installation.

Such wastes shall be discharged to an indirect waste receptor and a means of cooling shall be provided where necessary. Indirect waste piping from air conditioning units shall be sized according to the condensate-generating capacity of the units served. Branches from individual units shall be no smaller than the drain opening or drain connection on the unit.

Traps shall be provided at each air conditioning unit or cooling coil to main- tain atmospheric pressure in the waste piping.

Unless expressly prohibited by the Authority Having Jurisdiction, the point of indirect discharge for air conditioning condensate shall be one of the following: 1. The building sanitary drainage system. The building storm drainage system. A sump pump. A subsurface absorption pit or trench.

Cross connection control shall be provided at individual outlets, and where required, by containment of the premises. Each potential cross connection within the premises shall be protected. Private potable water supplies i. 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 either the taste, odor, color or potability of the water supply when the tank is placed in or returned to service.

Minimum Size distance : The minimum required air gap shall be twice the effective opening of a po- table water outlet unless the outlet is a distance less than 3 times the effective opening away from a wall or similar vertical surface, in which case, the minimum required air gap shall be 3 times the effective opening of the outlet. In no case shall the minimum required air gap be less than that shown in Table Table Side walls, ribs or similar obstructions do not affect air gaps when spaced from inside edge of the spout opening a distance greater than three times the diameter of the effective opening for a single wall, or a distance greater than four times the diameter of the effective opening for two intersecting walls.

The effect of three or more such vertical walls or ribs has not been determined. In such cases, the air gap shall be measured from the top of the wall. Hose connection vacuum breaker - ASSE 3. Backsiphonage, Continuous Pressure, Health Hazard 1.

Back Pressure, Non-Health Hazard 1. Back Pressure, Health Hazard 1. Clearances shall be as recommended by the manufacturer.

Vacuum breakers and other devices with vents shall not be located within fume hoods. Pressure vacuum breakers 2. Spill-resistant vacuum breakers 3. Double check valve assemblies 4. Double check detector assemblies 5. Reduced pressure detector assemblies c. 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. The distance from the outlet to the high water level shall be measured from the critical point of the po- table water supply outlet. Where an ASSE device must be installed in the water supply piping external to a carbonated bever- age dispenser, the piping from the device to the beverage dispenser shall be acid resistant and not copper. The piping in such systems shall be approved for potable water.

Atmospheric vacuum breaker AVB 2. Pressure vacuum breaker PVB 3. Spill-resistant vacuum breaker SVB 4. Where systems include a chemical injector or any provisions for chemical injection, the potable water supply shall be protected by the following: 1. 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: 1. The heat transfer medium is either potable water or contains only substances that are recognized as safe by the U.

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. 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 provid- ing a space between the two walls that is vented to the atmosphere. Such equipment and devices includes, but is not limited to, chemical dispensers, portable cleaning equipment, sewer and drain cleaning equipment, and dental pump equipment.

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.

A separation of ten feet shall be maintained from such systems. When a water line parallels or crosses over or under a sewer, a minimum clearance of 12 inches in all directions shall be maintained. The annular space between the pipe and the sleeve shall be resiliently sealed watertight.

An elevated water tank. A hydro-pneumatic pressure booster system. A water pressure booster pump. The covers of gravity tanks shall be vented with a return bend vent pipe having an area not less than the area of the down feed riser pipe and the vent shall be screened with corrosion resistant screen having not less than 14 and not more than 20 openings per linear inch. The procedure used shall be as follows or an approved equivalent: 1.

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. 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. 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 Appendix B gives recommendations concerning allowances to be made in sizing water piping because of the properties of the water.

This valve or stopcock shall be provided with an approved curb valve box. When the build- ing water service enters a crawl space, the building valve shall be readily accessible. Where there are two or more water services serving one building, a check valve shall be installed on each service in addition to the above shutoff valves.

In single dwelling units, the building valve required by Section These valves shall be accessible in the dwelling unit that they control. Except as permitted in Section In individual dwelling units where powder rooms or bath- room 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. These valves shall be accessible. Each sill cock and wall hydrant shall be separately controlled by a valve inside the building. If a shutoff valve is also pro- vided in the hot water supply from the heater, it shall not isolate any safety devices from the heater or storage tank. The valve shall not be less in size than the building water service pipe. Flushometer tank pressure assisted water closets require a minimum of 25 psig static pressure.

A Half-Bath or Powder Room, for the purposes of this Table, consists of one water closet and one lavatory. When WSFU values are added to determine the demand on the water distribution system or portions thereof, round the sum to the nearest whole num- ber before referring to Table WSFU values of 0. Values of 0. The requirement of Section 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. Relief valves shall discharge in accordance with Sections When a pressure reducing valve is installed, a gauge port or pressure gauge with pressure range of 0 - psi shall be installed within 24 inches down stream of the reducing valve.

Arresters shall be accessible for replacement. An approved electric heat tracing system shall be permitted to be used to satisfy the requirements of Sec- tion Hot water storage tanks shall be adequate in size, when combined with the BTUH input of the water heating equipment, to provide the rise in temperature necessary.

See Sections 3. No further mixing of water shall be permitted downstream of the automatic compensating valve. No further mixing of water shall be permitted downstream of the automatic temperature controlled mixing valve. These devices alone shall not supersede the other require- ments of Section These devices shall be installed in an accessible location and alone shall not supersede the other requirements of Section Temperature-Actuated Mixing Valves: Where temperature-actuated mixing valves are installed to control the in-line hot water supply temperature in the water distribution system.

Such devices shall be installed at the hot water source and alone shall not supersede the other requirements of Section Alternative Methods: The use of a combination of water temperature control or limiting devices that comply with the standards listed in Table 3. Plastic piping used for hot water distribution shall conform to the requirements of Section 3.

NOTE: The working pressure rating for certain approved plastic piping materials varies depending on material composition, pipe size, wall thickness and method of joining. Plastic pipe or tube shall not be used downstream from instantaneous water heaters, immersion water heat- ers or other heaters not having approved temperature safety devices.

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 psi. When the water heater is protected by a pressure relief valve or combination pressure temperature relief valve having a pressure setting higher than psi, a separate pressure relief valve shall be provided to protect the piping.

The relief valve for the piping shall comply with Section Thermal expansion shall be controlled as required under Section Drip pans shall be watertight and constructed of corrosion-resistant materials. Metallic pans shall be 24 gage minimum. Non-metallic pans shall be. Discharge from a relief valve into a water heater pan shall be prohibited.

Water heaters used for space heating shall be listed for such use. Piping and components connected to a water heater for space heating application shall be suitable for use with potable water.

The temperature control device shall be an ASSE listed device. Pressure vessels used for heating water or storing water at pressures above atmospheric shall be protected by approved safety devices in accordance with one of the following methods: 1. A separate pressure relief valve and a separate temperature relief valve; or 2.

A combination pressure and temperature relief valve; or 3. 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. The valves shall have a relief setting of not more than the pressure rating of the tank, or psig maxi- mum, 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 not less than degrees 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. The valves shall be installed so that the temperature sensing element is immersed in the hottest water within the top 6 inches of the tank. See Section 3.

Tankless instantaneous water heaters shall have an overheat prevention device to shutoff the unit in the event of unsafe high water temperature. The pressure and temperature tank protection required by Section 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. Discharge pipes from temperature relief valves and combination pressure-temper- ature relief valves shall be listed in Table 3.

The pressure rating of the pipe at deg F is not required to equal or exceed the pressure setting of the relief valve. There shall be no shut-off valve, check valve or other restricting device between a relief valve and the pressure vessel or piping system being protected. The discharge end of the 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. If the point of disposal 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 A visible air gap shall be provided in the room or space in which the relief valve is located.

EXCEPTION: 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. Where such relief valves for independent systems are discharged into a common grav- ity drain or indirect waste pipe, the drain or waste pipe shall be sized according to the largest discharge pipe served. 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 combina- tion temperature-pressure relief valve shall also be replaced and shall not be reused. Piping materials shall be as recommended by the system manufacturer and be listed in Table 3.

Manifolds having shutoff valves shall be readily accessible. Tube bundles for manifold systems shall be supported in accordance with Chapter 8 of this Code. Does not include branches of the building drain. In single dwelling units, no more than six water closets or bathroom groups shall be installed on a 3" building drain or building sewer, or branches thereof.

In other than single dwelling units, no more than four water closets or bathroom groups shall be installed on a 3" building drain or building sewer, or branches thereof. Mixed Water Closets on 3" Drains Where 3" drainage piping serves a mixture of 1. The stack size shall be permitted to be reduced as the DFU load decreases on the upper portion of the stack. The offset shall be sized as a building drain See Table A relief vent shall be provided for the offset as required by Section Only drains that must be lifted for gravity discharge shall be connected to such sump pits.

All other drains shall discharge by gravity. Sump pits shall be a minimum of 15 inches in diameter and 18 inches deep, and be accessible, tightly covered, and vented. The size of grinder pump discharge piping shall be: 1.

The discharge piping from a grinder pump ejector shall include a backwater valve and a full-way shutoff valve. A sewage ejector or sewage pump receiving the discharge from a water closet or urinal shall have a mini- mum capacity of 20 gallons per minute. The discharge piping from a sewage ejector and sewage pump shall include a backwater valve and a full- way shutoff valve.

In other than single dwelling units, ejectors and pumps other than grinders shall be capable of passing a 2 inch diameter solid. Direct-mounted equipment may be manually or automatically operated.

The installation of manually or automatically operated equipment shall not be subject to the venting requirements of this Code, but shall be vented only as required for proper operation of the equipment. If the equipment provides a proper water seal, additional traps are not required. Horizontal branch drain connections shall not be made within 10 pipe diameters downstream from the base of a stack.

Branch drains shall not connect between the base of a stack and its relief vent. Branch drains shall be permitted to connect to a horizontal stack offset, provided that the connection is not less than 10 pipe diameters downstream from the upper portion of the stack b.

Fixture or branch drain connections shall not be made to such stacks in the suds pressure zones except where relief vents complying with Section Zone 1 - at offsets greater than 45 degrees from vertical. A suds pressure zone shall extend 40 pipe diam- eters up the stack above the offset, 10 pipe diameters downstream from the base of the upper portion of the stack, and in the horizontal offset, 40 pipe diameters upstream from the top of the lower portion of the stack.

Zone 2 - at the base of a soil or waste stack. A suds pressure zone shall extend 40 pipe diameters up the stack above its base. Zone 3 - in the horizontal drain beyond the base of a soil or waste stack.

A suds pressure zone shall extend 10 pipe diameters from the base of the stack. Also, if a turn greater than 45 degrees occurs in the horizontal drain less than 50 feet from the base of the stack, suds pressure zones shall exist 40 pipe diameters upstream and 10 pipe diameters downstream from the horizontal turn. Zone 4 - in a vent stack at the base of a soil or waste stack.

Where a vent stack connects above or beyond the base of a soil or waste stack, a suds pressure zone shall extend up the vent stack to a level equal to the level of the suds pressure zone in the soil or waste stack.

Stacks that are less than three stories in height. Stacks in individual dwellings having their own building sewer. The protection of trap seals from siphonage, aspiration, or back-pressure shall be accomplished by the appropriate use of soil or waste stacks with adequate venting in accordance with the requirements of this Code. Venting systems shall be designed and installed so that at no time will trap seals be subjected to a pneu- matic pressure differential of more than one inch of water column under design load conditions.

If a trap seal is subject to loss by evaporation, means shall be provided to prevent the escape of sewer gas. See Section 5. To the building drain within 10 pipe diameters downstream from the base of the stack.

Where drainage stacks have ten or more branch intervals, a relief vent shall be provided for each ten branch intervals, starting at the top of the stack. The lower end of each relief vent shall connect to the drainage stack as a yoke vent below its tenth branch interval.

This relief vent may be a stack vent for the lower portion of the drainage stack. EXCEPTION: Where a roof is used for any purpose other than weather protection and maintaining equip- ment, vents shall extend at least 7 feet above the roof and shall be properly supported. Vent terminals shall not be located where vapors can enter the building. No vent terminal shall be located directly beneath any door, window, or other ventilating opening of a building or of another building, nor shall any such vent terminal be within 10 feet horizontally of such open- ing unless it is at least 2 feet above the top of such opening.

Where a vent terminal is within 10 feet horizontally and less than 2 feet above a ventilation opening described in Section Other- wise, the vent terminal shall comply with Section Otherwise, the vent terminal shall comply with Section Search icon An illustration of a magnifying glass.

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