+---
+title: General-Duty Valves for Plumbing Piping
+category: Plumbing
+toc_depth: 3
+description: >
+ When to use: general-duty isolation, check, and balancing valves in domestic
+ potable cold water, domestic hot water, and hot water recirculation piping in
+ commercial, institutional, and industrial buildings; gate, ball, globe, butterfly,
+ swing check, silent check, wafer check, and manual or automatic balancing valves
+ NPS 1/4 through NPS 12 from the water service entrance to fixture shutoffs and
+ equipment connections, rated to 250 psi CWP and 250 degF, with mandatory NSF 61/372
+ lead-free certification.
+ Not intended for: hydronic heating, chilled, and condenser water valves (see
+ [[sync/hvac-piping-valves]]); backflow preventers (see [[sync/backflow-prevention]]);
+ thermostatic mixing valves, pressure-reducing valves, and water hammer arrestors
+ (see [[sync/plumbing-specialties]]); fire protection control valves; buried
+ waterworks gate valves NPS 4 and larger (AWWA C509/C515); natural gas valves
+ (see [[sync/natural-gas-piping]]); pipe, fittings, and routing (see
+ [[sync/domestic-water-piping]]); and valve supports (see [[sync/hangers-and-supports]]).
+---
+
+# Scope {toc}
+
+## This standard governs the materials, ratings, end connections, operators, identification, and acceptance testing of general-duty valves installed in domestic water piping within building interiors.
+
+### General-duty valves are the isolation, check, and flow-balancing valves that serve the building water distribution system rather than a single packaged appliance. {note}
+
+### This standard covers gate, ball, globe, and butterfly isolation valves; swing, silent (spring-loaded), and wafer check valves; and manual and automatic balancing valves, in domestic potable cold water, domestic hot water, and hot water recirculation service. {note}
+
+### Coverage extends from the building water service entrance through all interior distribution piping to fixture shutoffs and equipment connections. {note}
+
+### Valves shall be furnished and installed for the size range NPS 1/4 through NPS 12 (DN 8 through DN 300) inclusive.
+
+### Valves shall be suitable for continuous service at system pressures up to 250 psi cold working pressure (CWP) and water temperatures up to 250 degF.
+
+### Each valve in contact with potable water shall carry current third-party certification to NSF/ANSI 61 and NSF/ANSI/CAN 372.
+
+### This standard is a plumbing-discipline companion to [[sync/hvac-piping-valves]]; the two share valve types and manufacturers but differ in that potable-water lead-free certification is mandatory here, and valve placement is governed by the plumbing code rather than the mechanical code. {note}
+
+### The following are outside this standard and are governed elsewhere: {note}
+
+- Hydronic heating, chilled water, and condenser water valves are covered by [[sync/hvac-piping-valves]].
+- Backflow prevention assemblies (RPZ, double check, pressure vacuum breaker) are covered by [[sync/backflow-prevention]].
+- Thermostatic mixing valves, pressure-reducing valves, and water hammer arrestors are covered by [[sync/plumbing-specialties]].
+- Fire protection sprinkler and standpipe control valves are a separate discipline and are not within plumbing valve scope.
+- Buried waterworks utility gate valves NPS 4 and larger are AWWA C509/C515 territory, despite the overlapping NPS range, and are not within building interior scope.
+- Natural gas shutoff and service valves are covered by [[sync/natural-gas-piping]].
+- Pipe, fittings, insulation, and distribution routing are covered by [[sync/domestic-water-piping]].
+- Hangers, supports, and seismic restraints for valve bodies are covered by [[sync/hangers-and-supports]].
+
+# Referenced Standards {toc}
+
+## Equipment, materials, and installation shall comply with the latest adopted edition of each of the following unless a specific edition is cited.
+
+## Where referenced standards conflict, the more stringent requirement shall govern unless the Engineer of Record directs otherwise in writing.
+
+| Standard | Title |
+|----------|-------|
+| MSS SP-67 | Butterfly Valves |
+| MSS SP-71 | Gray Iron Swing Check Valves |
+| MSS SP-80 | Bronze Gate, Globe, Angle and Check Valves |
+| MSS SP-110 | Ball Valves Threaded, Socket-Welding, Solder Joint, Grooved and Flared Ends |
+| MSS SP-125 | Gray Iron and Ductile Iron In-Line Spring Loaded Center-Guided Check Valves |
+| ASME B16.34 | Valves - Flanged, Threaded, and Welding End |
+| ASME B16.10 | Face-to-Face and End-to-End Dimensions of Valves |
+| ASME B31.9 | Building Services Piping |
+| NSF/ANSI 61 | Drinking Water System Components - Health Effects |
+| NSF/ANSI/CAN 372 | Drinking Water System Components - Lead Content |
+| IPC | International Plumbing Code (Section 606, Water Supply and Distribution) |
+| UPC | Uniform Plumbing Code (Chapter 6, Water Supply and Distribution) |
+| AWWA C800 | Underground Service Line Valves and Fittings |
+
+# Submittals {toc}
+
+## Action Submittals {toc}
+
+### The Contractor shall submit the following action submittals for review before procurement:
+
+- Product data for each valve type, size, and pressure class, including the manufacturer's catalog cut showing body material, trim, seat, stem, and operator.
+- Documentation of NSF/ANSI 61 and NSF/ANSI/CAN 372 listing for each valve in potable water service, identifying the certifying agency and listing number.
+- Pressure-temperature rating curves or tables for each valve, demonstrating that the rating exceeds the system design pressure plus the water hammer allowance.
+- A valve schedule correlating each valve number to its type, size, service, location, and normal operating position.
+- Shop drawings for valves requiring chain operators, gear operators, extended stems, or access provisions, showing dimensions and clearances.
+
+```datasheet
+label: Action Submittals
+type: checkbox
+options:
+ - Valve product data (body, trim, seat, stem, operator)
+ - NSF 61 / NSF 372 certification listing
+ - Pressure-temperature rating data
+ - Valve schedule (number, type, size, service, position)
+ - Shop drawings for geared, chain, or extended-stem valves
+default:
+ - Valve product data (body, trim, seat, stem, operator)
+ - NSF 61 / NSF 372 certification listing
+ - Pressure-temperature rating data
+ - Valve schedule (number, type, size, service, position)
+```
+
+## Informational Submittals {toc}
+
+### The Contractor shall submit the following informational submittals:
+
+- Certified factory hydrostatic shell and seat test reports for valves NPS 2-1/2 and larger.
+- Field hydrostatic pressure test records for the completed valve installation.
+- Manufacturer's installation, operation, and maintenance instructions.
+
+```datasheet
+label: Informational Submittals
+type: checkbox
+options:
+ - Factory shell and seat test reports (NPS 2-1/2 and larger)
+ - Field hydrostatic pressure test records
+ - Installation, operation, and maintenance instructions
+default:
+ - Field hydrostatic pressure test records
+ - Installation, operation, and maintenance instructions
+```
+
+## Closeout Submittals {toc}
+
+### The Contractor shall submit the following closeout submittals before final acceptance:
+
+- A final as-built valve schedule reflecting installed valve numbers, types, and locations.
+- Operation and maintenance manuals compiling product data, spare-parts lists, and maintenance procedures for each valve type.
+
+```datasheet
+label: Closeout Submittals
+type: checkbox
+options:
+ - As-built valve schedule
+ - Operation and maintenance manuals
+ - Spare-parts list
+default:
+ - As-built valve schedule
+ - Operation and maintenance manuals
+```
+
+# Quality Assurance {toc}
+
+## Each valve type shall be the product of a single manufacturer regularly engaged in the production of that valve type.
+
+### Standardizing each valve type on one manufacturer simplifies spare-parts stocking, operator familiarity, and warranty administration over the life of the building. {note}
+
+## Valves of the same type and size shall be identical and interchangeable throughout the project.
+
+## Each valve shall be permanently marked by the manufacturer with the body material, pressure rating, size, and applicable standard designation, in accordance with ASME B16.34 and the governing MSS standard.
+
+### Permanent body markings let a field inspector or future maintainer confirm a valve's rating without the original submittal, which is essential once the valve schedule is lost or the building changes hands. {note}
+
+## Bronze and brass valves NPS 2 and under shall comply with MSS SP-80 (gate, globe, check) or MSS SP-110 (ball) as applicable to the valve type.
+
+## Iron body swing check valves shall comply with MSS SP-71, and iron body butterfly valves shall comply with MSS SP-67.
+
+## Silent (spring-loaded center-guided) check valves shall comply with MSS SP-125.
+
+## Every valve wetted component in potable water service shall be certified to NSF/ANSI 61 for health effects and to NSF/ANSI/CAN 372 for lead content.
+
+### NSF 61 and NSF 372 are separate certifications: NSF 61 is a leach test for health effects, and NSF 372 is a wetted-surface lead-content analysis limiting lead to 0.25 percent. A valve listed to one is not automatically listed to the other. {note}
+
+### Specify lead-free compliance by certification listing, not by a material claim alone. Manufacturer literature sometimes asserts compliance without a formal third-party listing, which the certification listing requirement closes. {note}
+
+### The Safe Drinking Water Act (Section 1417) has required lead-free wetted components for potable water service on components installed on or after January 4, 2014. {note}
+
+# Environmental and Service Conditions {toc}
+
+## Valves shall be selected for the service pressure, temperature, and water chemistry of the system in which they are installed.
+
+### The pressure-temperature rating of each valve shall exceed the system design working pressure plus a water hammer allowance of not less than 50 psi.
+
+### A 200 psi CWP valve covers a 150 psi system static pressure with a 50 psi water hammer margin, which is the safe default for most commercial plumbing distribution. Specifying a 150 psi CWP valve on such a system leaves no surge margin and is a common cause of premature seat and stem failure. {note}
+
+## Valves in domestic hot water and hot water recirculation service shall be rated for continuous service at the maximum system water temperature.
+
+### Domestic hot water is typically distributed at or below 140 degF, well within the 250 degF service rating of the valves specified here; the rating margin accommodates recirculation, mixing-valve bypass, and thermal disinfection cycles. {note}
+
+## Valves installed in water known to be soft, low-pH, or high in chloride shall be specified with dezincification-resistant (DZR) brass or bronze bodies.
+
+### Dezincification-susceptible yellow brass in aggressive water pits and fails the valve body within five to ten years; in jurisdictions with corrosive water, DZR brass or bronze is mandatory rather than optional. {note}
+
+```datasheet
+label: System design working pressure
+type: range
+unit: psi
+min: 80
+max: 250
+step: 5
+default: 150
+```
+
+```datasheet
+label: Minimum valve CWP rating
+type: radio
+options:
+ - 150 psi CWP
+ - 200 psi CWP
+ - 300 psi CWP
+ - 600 psi CWP
+default: 200 psi CWP
+```
+
+```datasheet
+label: Maximum service water temperature
+type: range
+unit: degF
+min: 40
+max: 250
+step: 10
+default: 140
+```
+
+```datasheet
+label: Dezincification-resistant (DZR) brass/bronze required
+type: radio
+options:
+ - "Yes - aggressive water (soft, low-pH, or high-chloride)"
+ - "No - standard water chemistry"
+default: "No - standard water chemistry"
+```
+
+# Valve Materials and Body Construction {toc}
+
+## Valve body material shall be matched to valve size and service.
+
+### Valves NPS 1/4 through NPS 2 shall have bronze or brass bodies.
+
+### Valves NPS 2-1/2 and larger shall have cast iron or ductile iron bodies with bronze or stainless steel trim.
+
+### Bronze is the correct 80 percent-case body material at and below NPS 2; above NPS 2 bronze becomes non-standard and substantially more expensive, and iron body is the correct choice. Specifying bronze valves above NPS 2 is a common and avoidable cost overrun. {note}
+
+### Stainless steel bodies shall be furnished where the water chemistry is aggressive beyond the corrosion resistance of DZR bronze, where indicated.
+
+## Stems shall be bronze, brass, or stainless steel, and shall be free of dezincification-susceptible alloy in aggressive water service.
+
+## Seats, discs, and resilient seals shall be selected by valve type.
+
+### Ball valve seats shall be PTFE or reinforced TFE.
+
+### Butterfly valve seats shall be EPDM or BUNA-N, suitable for potable water and for the service temperature.
+
+### Gate, globe, and check valve seats shall be bronze or stainless steel as integral or renewable seat rings.
+
+```datasheet
+label: Body material by size range
+type: select
+options:
+ - "NPS 1/4-2: bronze/brass body"
+ - "NPS 2-1/2-12: cast or ductile iron body, bronze trim"
+ - "Stainless steel body (aggressive water)"
+default: "NPS 1/4-2: bronze/brass body"
+```
+
+```datasheet
+label: Ball valve seat material
+type: radio
+options:
+ - PTFE
+ - Reinforced TFE (RTFE)
+default: PTFE
+```
+
+```datasheet
+label: Butterfly valve seat material
+type: radio
+options:
+ - EPDM
+ - BUNA-N (nitrile)
+default: EPDM
+```
+
+# End Connections {toc}
+
+## Valve end connections shall match the joining method of the adjacent piping.
+
+### Threaded ends shall be tapered pipe thread (NPT) conforming to ASME B1.20.1.
+
+### Solder-joint ends shall be furnished for connection to copper tube by soldered or brazed joint.
+
+### Press-connect ends shall be furnished where the adjacent copper or stainless tube is joined by press fitting, and the press jaw profile shall match the adjacent piping system.
+
+### Press-connect valves require the same jaw profile as the adjacent press-fit piping; a mismatched jaw leaves a joint incompletely pressed and is a hidden leak path. Confirm jaw compatibility before specifying press-connect valves. {note}
+
+### Grooved ends shall conform to the groove dimensions of the adjacent grooved coupling system.
+
+### Flanged ends shall conform to ASME B16.1 (iron) Class 125 or Class 250 as required by the valve pressure rating, with face-to-face dimensions per ASME B16.10.
+
+### Wafer and lug butterfly valves shall be installed between two mating flanges, and shall not be installed at a pipe end, union, or single-flange equipment nozzle.
+
+### A wafer valve is clamped between two flanges and has no body bolt holes of its own; specifying a wafer valve where only one mating flange exists creates an unfillable gap. A lug-style valve can terminate a run because it is tapped for through-bolts on each side. {note}
+
+```datasheet
+label: End connection type
+type: select
+options:
+ - Threaded (NPT)
+ - Solder joint
+ - Press-connect
+ - Grooved
+ - Flanged (Class 125)
+ - Flanged (Class 250)
+ - Wafer (between flanges)
+ - Lug (between or end of flange)
+default: Threaded (NPT)
+```
+
+# Isolation Valves {toc}
+
+## Isolation valves provide full open / full closed shutoff of a piping segment and shall be selected by function and size.
+
+### A valve selected for isolation shall be used only for full open / full closed service, not for throttling.
+
+### Where flow regulation is required, a globe valve, balancing valve, or automatic balancing valve shall be used instead of an isolation valve.
+
+### Throttling a valve designed only for isolation erodes the seat and disc, which is why isolation service and throttling service must be separated at valve selection. {note}
+
+## Ball Valves {toc}
+
+### Ball valves shall be the default isolation valve for piping NPS 2 and under in domestic water service.
+
+### Ball valves shall be bronze body, full port, with a PTFE or RTFE seat and a blowout-proof stem, conforming to MSS SP-110.
+
+### Ball valves shall be furnished with a lever handle, or with a tee handle where a lever would obstruct adjacent equipment.
+
+### Ball valves are the correct choice wherever a valve is operated frequently. They give bubble-tight shutoff and a clear quarter-turn open/closed indication, and they tolerate repeated cycling far better than gate valves. {note}
+
+```datasheet
+label: Ball valve port
+type: radio
+options:
+ - Full port
+ - Standard port
+default: Full port
+```
+
+```datasheet
+label: Ball valve handle type
+type: radio
+options:
+ - Lever handle
+ - Tee handle
+ - Lever with locking provision
+default: Lever handle
+```
+
+## Gate Valves {toc}
+
+### Gate valves NPS 2 and under shall be bronze or brass body, solid wedge, with a non-rising stem, conforming to MSS SP-80.
+
+### Gate valves NPS 2-1/2 and larger shall be iron body, resilient or bronze-mounted wedge, flanged, with an outside screw and yoke (OS&Y) rising stem.
+
+### Gate valves shall be used only where the valve is operated infrequently and remains in a fixed position.
+
+### Gate valves are designed for infrequent full-open / full-closed service. Where weekly or more frequent operation is expected, the stem packing and wedge wear prematurely; specify a ball valve for frequently operated isolation. {note}
+
+### OS&Y rising stems on large valves give a visible open/closed indication, which non-rising stems on small valves do not. {note}
+
+```datasheet
+label: Gate valve stem type
+type: radio
+options:
+ - Non-rising stem (NRS)
+ - Outside screw and yoke (OS&Y), rising stem
+default: Non-rising stem (NRS)
+```
+
+```datasheet
+label: Gate valve seat (NPS 2-1/2 and larger)
+type: radio
+options:
+ - Resilient seat
+ - Bronze-mounted (metal seat)
+default: Resilient seat
+```
+
+## Butterfly Valves {toc}
+
+### Butterfly valves shall be furnished for isolation in piping NPS 2-1/2 and larger where a compact valve is required, conforming to MSS SP-67.
+
+### Butterfly valves shall be iron body, wafer or lug type, with a stainless steel disc, a stainless steel or coated stem, and an EPDM or BUNA-N seat.
+
+### Butterfly valves NPS 6 and larger, and any butterfly valve subject to frequent operation, shall be furnished with a gear operator and position indicator.
+
+### Butterfly valves NPS 4 and smaller may be furnished with a lever (notched throttling plate) operator.
+
+### Butterfly valves shall not be specified for throttling (partial-open) service; where flow regulation is required, a globe valve or an automatic balancing valve shall be used.
+
+### Partial-open operation erodes the butterfly seat and disc rapidly, which is why throttling service requires a valve type whose geometry is suited to it. {note}
+
+```datasheet
+label: Butterfly valve end style
+type: radio
+options:
+ - Wafer
+ - Lug
+default: Lug
+```
+
+```datasheet
+label: Butterfly valve operator
+type: radio
+options:
+ - Lever handle (NPS 4 and smaller)
+ - Gear operator with position indicator
+default: Gear operator with position indicator
+```
+
+## Globe Valves {toc}
+
+### Globe valves shall be furnished where throttling or frequent flow regulation is required in piping NPS 2 and under, conforming to MSS SP-80.
+
+### Globe valves shall be bronze body with a renewable composition or PTFE disc suited to the service temperature.
+
+### The globe valve's seat geometry is designed for throttling and tolerates the erosive condition that destroys an isolation valve held partly open. {note}
+
+# Check Valves {toc}
+
+## Check valves prevent reverse flow and shall be selected by orientation, velocity, and slam potential.
+
+## Swing Check Valves {toc}
+
+### Swing check valves NPS 2 and under shall be bronze body, Class 125, with threaded or solder ends, conforming to MSS SP-80.
+
+### Swing check valves NPS 2-1/2 and larger shall be iron body, Class 125, flanged, with bronze trim, conforming to MSS SP-71.
+
+### Swing check valves shall be installed only in horizontal runs (or vertical runs with upward flow) where forward velocity is sufficient to hold the disc open.
+
+### On vertical risers and pump discharge, a silent check valve shall be used in place of a swing check valve.
+
+### Swing check valves require a horizontal run and sufficient forward velocity to open and seat properly; on vertical risers or pump discharge they chatter and slam, making a spring-loaded silent check the correct selection. {note}
+
+## Silent (Spring-Loaded) Check Valves {toc}
+
+### Silent check valves shall be furnished on pump discharge, on hot water recirculation pump discharge, and on vertical risers, conforming to MSS SP-125.
+
+### Silent check valves shall be bronze or iron body, center-guided, spring-loaded, with a stainless steel spring, in wafer or flanged style.
+
+### The spring closes a silent check valve before flow reverses, eliminating the slam and water hammer that a swing check produces when pump flow stops. This non-slam behavior is why recirculation and pump-discharge service calls for silent checks. {note}
+
+### Silent check valves in potable water service shall be NSF/ANSI 61 and NSF/ANSI/CAN 372 certified.
+
+## Wafer Check Valves {toc}
+
+### Wafer check valves shall be furnished where installation space is constrained and the valve is installed between two flanges.
+
+### Wafer check valves shall be dual-plate or center-guided spring type, with a stainless steel spring and EPDM or potable-rated seat.
+
+```datasheet
+label: Check valve type by service
+type: select
+options:
+ - "Swing check - horizontal run, low velocity"
+ - "Silent (spring-loaded) - pump discharge, recirculation, vertical riser"
+ - "Wafer check - space-constrained between flanges"
+default: "Silent (spring-loaded) - pump discharge, recirculation, vertical riser"
+```
+
+```datasheet
+label: Check valve body material
+type: radio
+options:
+ - "Bronze (NPS 2 and under)"
+ - "Iron body, bronze trim (NPS 2-1/2 and larger)"
+default: "Bronze (NPS 2 and under)"
+```
+
+# Balancing Valves {toc}
+
+## Balancing valves shall be furnished on each hot water recirculation branch to distribute return flow and maintain delivery temperature throughout the loop.
+
+### Each hot water recirculation branch shall have a balancing valve at its connection to the return main.
+
+### A recirculation loop without balancing valves at each branch starves the far branches and over-circulates the near ones, producing cold delivery at distant fixtures and scalding risk near the heater. Balancing valves equalize the return flow so every fixture receives hot water promptly. {note}
+
+## Manual Balancing Valves {toc}
+
+### Manual balancing valves shall be the memory-stop type with integral measuring ports for differential pressure readout.
+
+### Manual balancing valves shall be furnished for recirculation branches NPS 3/4 and NPS 1 as the default selection.
+
+### A memory stop lets the balancer set, lock, and later re-establish the calibrated position after the valve has been closed for service, preserving the commissioned balance. {note}
+
+## Automatic Balancing Valves {toc}
+
+### Automatic (pressure-independent) balancing valves shall be furnished where the recirculation system experiences variable differential pressure that a fixed-orifice manual valve cannot accommodate.
+
+### Automatic balancing valves shall be cartridge-type, bronze body, maintaining the set flow within plus or minus 10 percent over a differential pressure range of 2 psi to 50 psi.
+
+### A pressure-independent valve holds its set flow automatically as system differential pressure swings, which a manual memory-stop valve cannot do; it is the right choice where pumps cycle or loads vary widely. {note}
+
+```datasheet
+label: Balancing valve type
+type: radio
+options:
+ - Manual memory-stop (fixed orifice, measuring ports)
+ - Automatic pressure-independent (cartridge)
+default: Manual memory-stop (fixed orifice, measuring ports)
+```
+
+```datasheet
+label: Manual balancing valve size (recirculation branch)
+type: select
+options:
+ - NPS 1/2
+ - NPS 3/4
+ - NPS 1
+ - NPS 1-1/4
+ - NPS 1-1/2
+default: NPS 3/4
+```
+
+# Operators and Stem Provisions {toc}
+
+## Valve operators shall be selected for valve size, operating frequency, and accessibility.
+
+### Valves up to NPS 6 shall be hand-operated by lever, handwheel, or gear as appropriate to the valve type.
+
+### Valves NPS 8 and larger, and any valve more than 7 ft above the finished floor, shall be furnished with a gear operator and, where above reach, a chain wheel.
+
+### Chain-operated valves shall have the chain looped to terminate approximately 6 ft above the finished floor.
+
+## Valves in insulated piping shall be furnished with stem extensions clearing the insulation.
+
+### Stem extensions shall project not less than 2 in. (50 mm) beyond the outside diameter of the pipe insulation.
+
+### Valves in cold or chilled water piping with vapor-barrier insulation shall be furnished with extended stems and non-conducting handles so the insulator does not breach the vapor barrier at each valve.
+
+### Omitting extended stems on vapor-barrier-insulated piping forces the insulator to cut the vapor barrier at every valve, creating condensation entry points that wet the insulation and corrode the pipe. The extension lets the insulation and vapor barrier run continuous past the valve. {note}
+
+```datasheet
+label: Operator type
+type: select
+options:
+ - Lever handle
+ - Handwheel
+ - Gear operator
+ - Gear operator with chain wheel
+default: Lever handle
+```
+
+```datasheet
+label: Stem extension for insulated piping
+type: radio
+options:
+ - "Not required (uninsulated)"
+ - "Standard extension (>= 2 in. beyond insulation OD)"
+ - "Extended stem with non-conducting handle (vapor-barrier insulation)"
+default: "Not required (uninsulated)"
+```
+
+# Identification {toc}
+
+## Each valve other than a fixture supply stop shall be permanently identified and keyed to the project valve schedule.
+
+### Each valve shall carry a brass or stainless steel tag stamped with its valve number.
+
+### Valve tag characters shall be not less than 1/2 in. (13 mm) high.
+
+### Valve tags shall be attached with stainless steel wire, chain, or a non-corroding fastener.
+
+### A framed, laminated valve schedule correlating each valve number to its type, size, service, and location shall be mounted in the mechanical room.
+
+### Valves concealed above inaccessible ceilings or behind walls shall be located by an access panel or shown on the as-built drawings by [[drawing: concealed valve locations]].
+
+### Valves installed without tags and a valve schedule become unlocatable once the walls close, generating RFIs during commissioning and obstructing maintenance for the life of the building. The numbering system keyed to the schedule is what makes a valve findable years later. {note}
+
+```datasheet
+label: Valve tag material
+type: radio
+options:
+ - Brass
+ - Stainless steel
+ - Anodized aluminum
+default: Brass
+```
+
+# Testing {toc}
+
+## Valves shall be factory-tested and the installed system shall be field-pressure-tested before acceptance.
+
+### Each valve shall pass a factory shell hydrostatic test at 1.5 times the cold working pressure, per ASME B16.34.
+
+### Each valve shall pass a factory seat closure test at 1.1 times the rated pressure, per the governing MSS standard for its type.
+
+### The completed valve installation shall be field hydrostatically tested at 1.5 times the system design working pressure for a minimum of 4 hours, per ASME B31.9 Section 937.4.
+
+### The field pressure test shall show no visible leakage at any joint or valve stem.
+
+### Valves shall be in the full-open position during system pressure testing, except where a valve must isolate a section being tested separately.
+
+### Leaving valves open during the test proves the full system piping, not just the valve seats; closing a valve during a system test hides any leak path beyond it. {note}
+
+```datasheet
+label: Field test pressure
+type: range
+unit: psi
+min: 120
+max: 375
+step: 5
+default: 225
+```
+
+```datasheet
+label: Field test hold duration
+type: range
+unit: hours
+min: 2
+max: 24
+step: 1
+default: 4
+```
+
+# Installation {toc}
+
+## Valves shall be installed accessible for operation, maintenance, and removal.
+
+### Each valve shall be installed with its operator and any measuring ports accessible without removing adjacent equipment or finished construction.
+
+### Valves shall be installed in the orientation recommended by the manufacturer; check valves shall be installed with the flow arrow oriented in the direction of normal flow.
+
+### Isolation valves shall be installed where required by the plumbing code, including at each fixture supply, each equipment connection, each branch serving two or more fixtures, each riser, and at the building water service entrance, per IPC Section 606 or the equivalent UPC provision.
+
+### The plumbing code's valve placement rules exist so that any fixture, branch, riser, or piece of equipment can be isolated for service without draining the whole system. Honoring them at design time avoids field-added valves and service shutdowns later. {note}
+
+### Unions or flanges shall be installed adjacent to threaded and flanged valves NPS 2 and under to permit valve removal without cutting the pipe.
+
+### Valves shall not be supported by the connected piping; valve weight shall be carried by the pipe supports in [[sync/hangers-and-supports]].
+
+### Valves shall be installed with stems oriented between the vertical-up and horizontal positions, and shall not be installed stem-down where sediment can collect on the stem and seat.
+
+### Dielectric isolation shall be maintained where a valve joins dissimilar metals, consistent with the piping requirements of [[sync/domestic-water-piping]].
+
+### Before installation, each valve shall be inspected and its interior cleared of shipping debris, and threaded ends shall be made up with a pipe-thread sealant compatible with potable water.
+
+```datasheet
+label: Valve removal provision (NPS 2 and under)
+type: radio
+options:
+ - Union adjacent to valve
+ - Flange adjacent to valve
+ - Press or grooved coupling permits removal
+default: Union adjacent to valve
+```
+
+# Delivery, Storage, and Handling {toc}
+
+## Valves shall be protected from damage and contamination from delivery through installation.
+
+### Valves shall be delivered with end protectors in place and with factory tags and markings intact.
+
+### Valves shall be stored indoors, off the ground, and protected from dirt, moisture, and freezing until installed.
+
+### Valves shall be handled by the body, not by the operator, handle, or stem, to avoid distorting the stem or seat.
+
+### Valves shall be kept in the closed or partly open position during storage as recommended by the manufacturer to protect the seat.
+
+# Warranty {toc}
+
+## The Contractor shall warrant valves against defects in materials and workmanship for the warranty period.
+
+### Valves shall be warranted for a period of not less than one year from the date of substantial completion.
+
+### Specific valve types may carry an extended manufacturer warranty where indicated.
+
+```datasheet
+label: Valve warranty period
+type: radio
+options:
+ - 1 year from substantial completion
+ - 2 years from substantial completion
+ - Manufacturer standard warranty
+default: 1 year from substantial completion
+```
+
+# Spare Parts {toc}
+
+## The Contractor shall furnish spare parts and operating provisions to the Owner at closeout.
+
+### The Contractor shall furnish spare seats, discs, and stem packing kits for valves NPS 2-1/2 and larger, in the quantity indicated.
+
+### The Contractor shall furnish a wrench or operating key for each type of valve requiring a removable operator.
+
+```datasheet
+label: Spare parts package
+type: checkbox
+options:
+ - Spare seats and discs (NPS 2-1/2 and larger)
+ - Stem packing kits
+ - Operating wrenches / keys for removable operators
+default:
+ - Operating wrenches / keys for removable operators
+```