SynC™

SynC · SynC Standards

Wet-Pipe Fire Sprinkler Systems

Rev7
IssuedSep 14, 2026
Contents

Revision history

Download
Build a datasheet from this standard Start a project with this standard already attached — one click, no setup.
Use in a project

1 Scope

NOTE This standard governs the design basis, sprinkler selection, riser and zone arrangement, alarm and supervisory provisions, installation, acceptance testing, warranty, and spares of automatic wet-pipe fire sprinkler systems, and it is the family standard from which the dry-pipe and pre-action layers take everything common to an automatic sprinkler system. (1.1)
NOTE A wet-pipe system holds water under supply pressure in every pipe at all times, so that the opening of a single sprinkler discharges water onto the fire immediately and moves water through the riser, where the flow is detected and alarmed. (1.2)
NOTE The scope begins at the connection between the underground fire service lateral and the system riser, or at the downstream side of the backflow prevention assembly or control valve assembly where one is provided, and extends through the riser, feed mains, cross mains, and branch lines to every sprinkler, floor and zone control assembly, alarm device, drain, and test connection the system contains. (1.3)
NOTE The following are governed elsewhere and are outside this standard: (1.4)
  • pipe, fittings, joints, control valves, check valves, waterflow and supervisory switches, main drains, pressure gauges, hangers, and seismic brace hardware, which this standard invokes from Fire Protection PipingFire Protection Piping and SpecialtiesResolves to the current adopted revision.sync/fire-protection-piping
  • the fire department connection body, inlets, check valve, drain, and signage, governed by Fire Department ConnectionsFire Department ConnectionsResolves to the current adopted revision.sync/fire-department-connections
  • the dry-pipe valve, air supply, water delivery time, and trip test of a dry-pipe system, governed by Dry Pipe Fire Sprinkler SystemsDry-Pipe Fire Sprinkler SystemsResolves to the current adopted revision.sync/dry-pipe-fire-sprinkler-systems as a layer over this standard
  • the pre-action or deluge valve, detection interlock, and supervision of a pre-action or deluge system, governed by Pre Action And Deluge Sprinkler SystemsPre-Action and Deluge Sprinkler SystemsResolves to the current adopted revision.sync/pre-action-and-deluge-sprinkler-systems as a layer over this standard
  • storage occupancies designed under the storage chapters of NFPA 13, including in-rack sprinklers and ESFR and CMSA ceiling sprinklers
  • fire pumps, jockey pumps, drivers, and controllers, governed by Fire PumpsFire PumpsResolves to the current adopted revision.sync/fire-pumps and Fire Pump ControllersFire Pump ControllersResolves to the current adopted revision.sync/fire-pump-controllers
  • the underground fire service main, its thrust restraint, and its flushing, governed by Underground Fire Service MainsUnderground Fire Service MainsResolves to the current adopted revision.sync/underground-fire-service-mains
  • the backflow prevention assembly on the fire service, governed by Backflow PreventionBackflow PreventionResolves to the current adopted revision.sync/backflow-prevention
  • standpipe risers and hose connections, including the standpipe demand on a combined riser, governed by Standpipe SystemsStandpipe SystemsResolves to the current adopted revision.sync/standpipe-systems
  • the fire alarm control unit, notification appliances, and supervising station connection that receive sprinkler signals, governed by Fire Alarm SystemsFire Alarm SystemsResolves to the current adopted revision.sync/fire-alarm-systems
  • firestopping of sprinkler pipe penetrations, governed by FirestoppingFirestoppingResolves to the current adopted revision.sync/firestopping
  • contractor and designer qualification, submittal administration, coordination, and record documents common to all fire suppression work, governed by Common Work Results Fire SuppressionCommon Work Results for Fire SuppressionResolves to the current adopted revision.sync/common-work-results-fire-suppression
1.5 Wet-pipe sprinkler systems shall comply with NFPA 13 in the edition adopted by the Authority Having Jurisdiction, with the International Building Code, and with the International Fire Code as adopted locally.
1.6 Where a local amendment modifies NFPA 13, the International Building Code, or the International Fire Code, the local amendment shall govern unless it is less stringent than the base document, in which case the base document governs.
1.7 The Engineer of Record shall confirm the adopted edition of NFPA 13 before design begins.
NOTE Successive editions of NFPA 13 have changed the hazard classification examples, the density and area design basis, the quick-response requirements, the air venting requirement, the seismic bracing rules, and the obstruction rules, so the adopted edition decides several of the values this standard asks for. (1.8)
1.9 The Engineer of Record shall confirm whether any portion of the building falls under the storage chapters of NFPA 13 before this standard is applied to that portion.
1.10 The Contractor shall comply with Common Work Results Fire SuppressionCommon Work Results for Fire SuppressionResolves to the current adopted revision.sync/common-work-results-fire-suppression in addition to this standard.

2 Referenced Standards

2.1 Materials, design, installation, and testing shall comply with the latest adopted edition of each of the following unless a specific edition is cited.
2.2 Where the contract documents, the Authority Having Jurisdiction, or two referenced standards impose conflicting requirements, the more stringent requirement shall govern unless the Engineer of Record directs otherwise in writing.
Standard Title
NFPA 13 Standard for the Installation of Sprinkler Systems
NFPA 14 Standard for the Installation of Standpipe and Hose Systems
NFPA 20 Standard for the Installation of Stationary Pumps for Fire Protection
NFPA 24 Standard for the Installation of Private Fire Service Mains and Their Appurtenances
NFPA 25 Standard for the Inspection, Testing, and Maintenance of Water-Based Fire Protection Systems
NFPA 72 National Fire Alarm and Signaling Code
NFPA 291 Recommended Practice for Water Flow Testing and Marking of Hydrants
IBC International Building Code (Chapter 9)
IFC International Fire Code (Chapter 9)
ASCE 7 Minimum Design Loads and Associated Criteria for Buildings and Other Structures (Chapter 13)
UL 199 Automatic Sprinklers for Fire-Protection Service
UL 1626 Residential Sprinklers for Fire-Protection Service
UL 193 Alarm Valves for Fire-Protection Service
UL 262 Gate Valves for Fire-Protection Service
UL 312 Check Valves for Fire-Protection Service
UL 753 Alarm Accessories for Automatic Water-Supply Control Valves for Fire-Protection Service
UL 1091 Butterfly Valves for Fire-Protection Service
UL 1821 Thermoplastic Sprinkler Pipe and Fittings for Fire-Protection Service
UL 2443 Flexible Sprinkler Hose with Fittings for Fire Protection Service
FM 2000 Approval Standard for Automatic Sprinklers for Fire Protection
FM 1637 Approval Standard for Flexible Sprinkler Hose with Threaded End Fittings
FM Global Data Sheet 2-0 Installation Guidelines for Automatic Sprinklers
FM Global Data Sheet 3-26 Fire Protection for Nonstorage Occupancies

3 Submittals

3.1 Action Submittals

3.1.1 The Contractor shall submit the following for the Engineer of Record's review and the Authority Having Jurisdiction's approval before sprinkler system materials are procured:
  • working drawings prepared in accordance with the plans and calculations requirements of NFPA 13, showing pipe routing, pipe sizes, sprinkler types and locations, ceiling heights and construction, the hazard classification of each area, hanger and brace locations, and the location of every valve, drain, and test connection
  • a riser diagram showing the riser arrangement, each floor or zone control assembly, and every connection to the water supply, the fire department connection, and any combined standpipe riser
  • hydraulic calculations demonstrating the design density over the design area for each hazard area, with the hose stream allowance added, the water supply curve plotted against the total demand, and the safety margin this standard requires shown at the design point
  • product data for each sprinkler type, giving the listing, the nominal K-factor, the temperature rating, the thermal response classification, the finish, and the pressure rating
  • product data for the riser assembly, the floor and zone control assemblies, the waterflow and supervisory devices, the air vent, and the test and drain connections
  • product data and the listing for flexible sprinkler hose connections, where selected
  • the listing, the installation instructions, and the chemical compatibility advisory for CPVC pipe and fittings, where CPVC is selected under Fire Protection PipingFire Protection Piping and SpecialtiesResolves to the current adopted revision.sync/fire-protection-piping
  • seismic bracing calculations and details where bracing is required under this standard
Action Submittal Packagecheckbox
☑ Working drawings per NFPA 13
☑ Riser diagram
☑ Hydraulic calculations
☑ Sprinkler product data
☑ Riser, control assembly, and device product data
☐ Flexible sprinkler hose listing and product data
☐ CPVC listing, instructions, and compatibility advisory
☐ Seismic bracing calculations and details
3.1.2 Sprinkler piping shall not be fabricated or installed until the corresponding action submittals have been reviewed, returned, and approved by the Authority Having Jurisdiction.
NOTE The fire code official reviews the working drawings and calculations as the primary basis of the fire protection plan review, and a package submitted without the hazard classification of each area or without the supply curve plotted against the demand is the usual cause of a delayed approval at this trade. (3.1.3)

3.2 Informational Submittals

3.2.1 The Contractor shall submit the following with or before the action submittals:
  • the water supply flow test report on which the hydraulic calculations are based, giving the test location, the date, the static pressure, the residual pressure, and the flow
  • the qualification of the individual who prepared the working drawings and hydraulic calculations, as required by Common Work Results Fire SuppressionCommon Work Results for Fire SuppressionResolves to the current adopted revision.sync/common-work-results-fire-suppression
  • written confirmation from the Owner of the intended use and contents of each area on which the hazard classification is based
Informational Submittal Packagecheckbox
☑ Water supply flow test report
☑ Designer qualification
☐ Owner confirmation of intended use and contents

3.3 Closeout Submittals

3.3.1 The Contractor shall submit the following before the sprinkler system is accepted:
  • the Contractor's Material and Test Certificate for Aboveground Piping, signed by the installing Contractor and witnessed as this standard requires, recording the materials and joint types installed, the flushing, the hydrostatic test, the main drain test, and the operation of every alarm and supervisory device
  • as-built drawings recording field changes from the reviewed working drawings, including the installed location of every sprinkler, valve, drain, and test connection
  • an operation and maintenance manual including the riser and zone identification, the valve locations, the hazard classification and design basis of each area, the impairment procedure, and the NFPA 25 inspection, testing, and maintenance schedule for the system
  • verification that the hydraulic design information sign and the general information sign at each riser match the accepted calculations and the installed system
  • warranty documentation for the sprinkler installation and for each listed device
  • a signed receipt from the Owner for the spare sprinkler cabinet and the other spare parts delivered
Closeout Submittal Packagecheckbox
☑ Contractor's Material and Test Certificate for Aboveground Piping
☑ As-built drawings
☑ Operation and maintenance manual with the NFPA 25 schedule
☑ Hydraulic design and general information sign verification
☑ Warranty documentation
☑ Spare parts receipt

4 Quality Assurance

4.1 Designer and Installer Qualifications

4.1.1 The sprinkler system shall be designed and installed by personnel holding the qualifications required by Common Work Results Fire SuppressionCommon Work Results for Fire SuppressionResolves to the current adopted revision.sync/common-work-results-fire-suppression and by the Authority Having Jurisdiction.
4.1.2 Working drawings and hydraulic calculations shall be prepared by an individual whose qualification the Authority Having Jurisdiction accepts for water-based fire protection system layout.

4.2 Component Listing

4.2.1 Sprinklers, riser assemblies, control assemblies, alarm and supervisory devices, flexible sprinkler hose connections, and air vents shall be listed for fire protection service on the basis indicated in the datasheet.
Component Listing Basisradio
● Listed by a nationally recognized testing laboratory for fire protection service
○ Listed by a nationally recognized testing laboratory and FM Approved
4.2.2 Standard spray, extended coverage, and special application sprinklers shall be listed to UL 199, residential sprinklers shall be listed to UL 1626, and where the datasheet requires FM Approval each sprinkler shall additionally be approved to FM 2000.
NOTE A UL listing and an FM Approval test a sprinkler and its installation limits under different protocols, so a product holding one does not necessarily hold the other, and an insurer's FM requirement is confirmed at procurement rather than discovered at the acceptance inspection. (4.2.3)
4.2.4 A listed component shall not be replaced by an unlisted product, and a listed component shall not be replaced by a different listed product without the Engineer of Record's written acceptance and the Authority Having Jurisdiction's concurrence.

4.3 Coordination with Other Trades

4.3.1 The sprinkler Contractor shall resolve conflicts between sprinkler piping and ductwork, structure, light fixtures, cable tray, and ceiling systems on the coordination drawings before piping is fabricated.
4.3.2 The capacity of the structure at every hanger and brace attachment shall be confirmed with the structural engineer before hangers are installed, and supplemental framing shall be provided where the available structure cannot carry the imposed load.
4.3.3 Sprinkler positions in finished ceilings shall be coordinated with the ceiling layout, the light fixtures, and the air devices before the ceiling grid is installed.
NOTE Lightweight steel joists, metal deck between joists, and wood trusses are the structural conditions most often found unable to carry a hanger or brace load, and a hanger relocated in the field to reach adequate structure moves the branch line and the sprinkler with it. (4.3.4)

5 Environmental and Service Conditions

5.1 Freeze Exposure of Wet-Pipe Piping

5.1.1 Water-filled sprinkler piping shall be located only where the ambient temperature is maintained at or above 40°F.
5.1.2 The provision applied to any portion of the system exposed to temperatures below 40°F shall be as indicated in the datasheet.
Freeze Protection of Piping Exposed Below 40°Fselect
Not applicable, all wet-pipe piping within space maintained at or above 40°F
Listed dry-type sprinklers on the wet system
Listed premixed antifreeze solution in the exposed portion
Listed electric heat tracing with thermal insulation
Heated enclosure maintaining the piping above 40°F
Dry-pipe or pre-action system for the exposed portion
NOTE Loading dock canopies, walk-in freezers and coolers, unheated attics, exterior stair towers, and open parking levels are the pockets of a conditioned building that fall below 40°F, and the provision that fits each turns on how many sprinklers the pocket holds, whether power is available at it, and whether a separate dry-pipe valve and air supply can be justified for it. (5.1.3)
NOTE A dry-type sprinkler carries a sealed barrel that keeps water back in the heated wet pipe, so a handful of sprinklers in a freezer or under a canopy can be served from the wet system without a second system type; a pocket large enough to need many sprinklers or long exposed runs is served more reliably by heat tracing, an enclosure, or a dry-pipe portion. (5.1.4)
5.1.5 Where dry-type sprinklers are selected, the barrel length shall keep the water seal within the heated space, and the sprinkler shall be installed within the listed limits on barrel length and orientation.
5.1.6 Where an antifreeze solution is selected, it shall be a listed premixed solution used within the concentration and volume limits of its listing and of NFPA 13, and the general information sign shall state its presence and its type.
NOTE NFPA 13 no longer permits field-mixed antifreeze in a sprinkler system, because a field-mixed glycerin or glycol solution above its listed concentration ignites at the sprinkler and adds fuel to the fire it was meant to control. (5.1.7)
5.1.8 Where heat tracing is selected, it shall be listed for use on fire protection piping, shall be electrically supervised, and shall be installed with the insulation and monitoring its listing requires.
5.1.9 The extent of each portion of the system exposed to temperatures below 40°F shall be as indicated on the fire protection drawings.

5.2 System Working Pressure

5.2.1 The system working pressure shall be determined from Site Water Supply Pressure MaximumSite Water Supply Pressure MaximumParameterEach project supplies its own value.site-water-supply-pressure-maximum plus the churn pressure of any fire pump, less the elevation head to the point considered, and the working pressure class of every component shall be selected for it under Fire Protection PipingFire Protection Piping and SpecialtiesResolves to the current adopted revision.sync/fire-protection-piping.
5.2.2 Every sprinkler shall be rated for the maximum static pressure at its elevation.
NOTE Standard sprinklers are rated for 175 psi, and a sprinkler on a low floor of a tall building or downstream of a high-churn pump can see more than that at rest; a high-pressure sprinkler listing or a pressure-reducing arrangement is decided at design rather than discovered when the pump is started. (5.2.3)
5.2.4 Where the static pressure at any sprinkler would exceed the rating of the sprinklers selected, either sprinklers listed for the higher pressure shall be used in that portion or a listed pressure-reducing valve shall be provided under Fire Protection PipingFire Protection Piping and SpecialtiesResolves to the current adopted revision.sync/fire-protection-piping to limit the pressure in that portion.

5.3 Air Venting and Internal Corrosion

5.3.1 Each wet-pipe system with metallic pipe shall be provided with a single air vent of the type indicated in the datasheet, located at a high point of the system.
Wet-Pipe System Air Ventradio
○ Automatic air vent
○ Manual air vent
NOTE Air trapped at the high points of a wet system is the oxygen supply for the corrosion that pits the pipe from the inside, and venting it as the system fills is the lowest-cost corrosion control NFPA 13 requires; an automatic vent releases air on every refill without a technician present, and a manual vent depends on the fill procedure being followed. (5.3.2)
5.3.3 The internal corrosion protection approach for the system shall be selected under Fire Protection PipingFire Protection Piping and SpecialtiesResolves to the current adopted revision.sync/fire-protection-piping.
5.3.4 The air vent shall be arranged so that it does not discharge water where damage would result, and shall be isolable for service without draining the system.

6 Occupancy Hazard Classification

NOTE The hazard classification of each area sets the design density, the design area, the hose stream allowance, the supply duration, and several sprinkler selection rules, so it is the first decision this standard needs and the one whose error costs the most. (6.1)
6.2 The predominant occupancy hazard classification shall be as indicated in the datasheet.
Predominant Occupancy Hazard Classificationselect
Light Hazard
Ordinary Hazard Group 1
Ordinary Hazard Group 2
Extra Hazard Group 1
Extra Hazard Group 2
FM Global Hazard Category 1
FM Global Hazard Category 2
FM Global Hazard Category 3
Derived — the NFPA 13 occupancy hazard classification, or the FM Global hazard category where the FM Global design basis is selected, applied to the occupancy and contents of each area shown on the code summary (by default)
6.3 Where the building contains areas of more than one hazard classification, the classification and extent of each area shall be as indicated on the fire protection drawings.
6.4 Each hazard area shall be piped and calculated to its own density and area, and an area shall not be classified by the predominant occupancy around it.
NOTE NFPA 13 classifies an occupancy by the quantity and combustibility of its contents and the expected rate of heat release, not by the building's use group under the building code: (6.5)
  • Light Hazard covers low quantities of low-combustibility contents with a low rate of heat release, such as offices, classrooms, patient rooms, and places of worship.
  • Ordinary Hazard Group 1 covers moderate quantities of moderate-combustibility contents stacked no more than 8 ft high, such as parking garages, laundries, and bakeries.
  • Ordinary Hazard Group 2 covers moderate to high quantities of moderate to high combustibility stacked no more than 12 ft high, such as machine shops, repair garages, and library stack areas.
  • Extra Hazard Group 1 covers very high quantities of combustibles with little or no flammable liquid, such as certain woodworking and foam or plastic processing.
  • Extra Hazard Group 2 covers moderate to substantial quantities of flammable or combustible liquid, such as spray finishing and solvent cleaning.
NOTE A tenant fit-out that changes the contents of an area changes its classification, which is why the Owner's confirmation of intended use is a submittal and why the hazard classification of each area is stated on the general information sign at the riser. (6.6)
6.7 Where an occupancy is on the boundary between two classifications, the designer shall apply the more demanding classification or shall resolve the classification with the Authority Having Jurisdiction in writing before the hydraulic design is finalized.

7 Design Approach

7.1 Design Method

7.1.1 The design approach shall be as indicated in the datasheet.
Design Approachradio
● Density/area method
○ Room design method
○ Pipe schedule method where NFPA 13 permits it
○ FM Global data sheet design criteria
NOTE The density/area method sizes the system to deliver a stated density over the hydraulically most demanding area of the stated size; the room design method sizes it to the most demanding room and its communicating openings and is used where every room is enclosed by construction rated as NFPA 13 requires; the pipe schedule method fixes pipe sizes by table rather than by calculation and is permitted by NFPA 13 only for small new systems with a proven supply and for additions to existing pipe schedule systems; and the FM Global criteria replace the NFPA 13 tables with the data sheet values an FM-insured Owner's carrier requires. (7.1.2)
7.1.3 Where the pipe schedule method is selected, the Contractor shall demonstrate that the system falls within the size, hazard, and water supply limits NFPA 13 places on that method, and the Authority Having Jurisdiction shall have accepted the method before the working drawings are submitted.
7.1.4 Where the FM Global design criteria are selected, the hazard category, density, area, and hose demand shall be taken from the applicable FM Global data sheet, and the more demanding of the FM Global and NFPA 13 values shall govern each element of the design.

7.2 Design Density and Area

7.2.1 The design density shall be as indicated in the datasheet.
Design Densityrange
gpm/sq ft
0.050.10.150.20.250.30.350.40.450.50.6
Derived — the occupancy hazard classification and the design approach selected, applied to the design criteria of NFPA 13 Chapter 19 in the adopted edition or to the applicable FM Global data sheet (by default)
7.2.2 The design area shall be as indicated in the datasheet.
Design Arearange
sq ft
50075090010001200150020002500300040005000
Derived — the occupancy hazard classification and the design approach selected, with the design area adjustments selected applied, per NFPA 13 Chapter 19 in the adopted edition or the applicable FM Global data sheet (by default)
NOTE Under the 2022 and later editions of NFPA 13, each hazard classification carries a single design density and area in Chapter 19, so the pair follows from the classification; under the 2019 and earlier editions the designer selected any point on a density/area curve, and the curve was retired because the least demanding point was chosen so routinely that systems were being sized to the bottom of the curve rather than to the hazard. (7.2.3)
7.2.4 The design area adjustments applied shall be as indicated in the datasheet.
Design Area Adjustments Appliedcheckbox
☐ Reduction for quick-response sprinklers under a ceiling 20 ft or lower
☐ Increase for a ceiling sloped more than 2 in 12
☐ Increase for a dry-pipe or double-interlock pre-action system
NOTE The quick-response reduction shortens the design area by up to 40 percent as ceiling height falls, on the evidence that fast-opening sprinklers control a fire with fewer heads open; the sloped ceiling increase and the dry-pipe increase enlarge the area because heat travels farther under a slope before it opens a sprinkler and because a dry system opens sprinklers before water arrives. (7.2.5)
NOTE The dry-pipe and pre-action increase is invoked under the layer standard for that system type, and the layer states the delivery time it is paired with. (7.2.6)
7.2.7 The design area shall be the hydraulically most demanding area of the selected size in each hazard area, shaped as NFPA 13 requires, and the designer shall not interpolate between hazard classifications.

7.3 Hose Stream Allowance and Supply Duration

7.3.1 The hydraulic calculations shall add the hose stream allowance indicated in the datasheet to the sprinkler demand at the point NFPA 13 specifies for the water supply arrangement.
Hose Stream Allowancerange
gpm
501002505007501000
Derived — the occupancy hazard classification, per the water supply table of NFPA 13 Chapter 19 in the adopted edition or the applicable FM Global data sheet (by default)
NOTE NFPA 13 assigns a combined inside and outside hose allowance of 100 gpm to light hazard, 250 gpm to ordinary hazard, and 500 gpm to extra hazard, and the allowance stands in for the hose lines the fire department will charge from the same supply while the sprinklers are flowing; a calculation that omits it produces a system that looks compliant on paper and starves when the first attack line opens. (7.3.2)
7.3.3 Where the building contains inside hose connections, the portion of the allowance assigned to inside hose shall be applied at the hose connection as NFPA 13 requires, and the standpipe demand on a combined riser shall be applied under Standpipe SystemsStandpipe SystemsResolves to the current adopted revision.sync/standpipe-systems.
7.3.4 The water supply shall be capable of delivering the total demand for not less than the duration indicated in the datasheet.
Water Supply Durationrange
minutes
30456090120
7.3.5 The duration shall be not less than 30 minutes for light hazard, 60 minutes for ordinary hazard, and 90 minutes for extra hazard, and shall be within the band NFPA 13 sets for the hazard classification.
NOTE NFPA 13 sets the duration as a band for ordinary and extra hazard, and the point within the band is agreed with the Authority Having Jurisdiction and, on a stored supply, sizes the tank. (7.3.6)

7.4 Water Supply

7.4.1 The water supply source shall be as indicated in the datasheet.
Water Supply Sourceselect
Public water main
Public water main with fire pump
Stored water supply with fire pump
Public water main and stored water supply with fire pump
Gravity tank
Pressure tank
Per drawings — the fire protection riser diagram (deferred by default)
7.4.2 The water supply data on which the hydraulic calculations are based shall be obtained from a flow test conducted at or near the site in accordance with NFPA 291, and shall be as indicated on the fire protection drawings.
7.4.3 The flow test shall have been conducted not more than the period indicated in the datasheet before the date of the hydraulic calculation submittal.
Maximum Age of the Water Supply Flow Test at Submittalrange
months
6122436
7.4.4 The hydraulic calculations shall demonstrate that the total demand, including the hose stream allowance, falls below the water supply curve at the design point by not less than the safety margin indicated in the datasheet.
Water Supply Safety Margin at the Design Pointrange
psi
5101520
7.4.6 Where the available supply does not deliver the total demand at the required pressure, a fire pump shall be provided in accordance with Fire PumpsFire PumpsResolves to the current adopted revision.sync/fire-pumps.
7.4.7 Where a backflow prevention assembly is installed on the supply, its pressure loss at the total demand shall be included in the hydraulic calculations, using the assembly's published loss curve.
NOTE An assembly loss omitted from the calculation is the most common reason a wet-pipe system passes plan review and fails its main drain or forward-flow comparison at acceptance. (7.4.8)

7.5 Pipe Arrangement

7.5.1 The pipe arrangement shall be as indicated in the datasheet.
Pipe Arrangementselect
Tree
Looped feed and cross mains
Gridded branch lines
NOTE A tree arrangement feeds each branch line from one end and is the simplest to calculate and to modify; a loop feeds the cross mains from two directions and lowers friction loss to a remote area of a large floor plate; a grid connects the branch lines at both ends and delivers the smallest pipe sizes on a large flat ceiling, at the cost of the peaking analysis NFPA 13 requires and of hydraulic behavior that is harder to modify later. (7.5.2)
7.5.3 A gridded arrangement shall not be used on a dry-pipe, pre-action, or deluge system, which NFPA 13 prohibits.
7.5.4 Where the arrangement differs between systems or floors in the same building, the arrangement of each shall be as indicated on the fire protection drawings.

8 Piping, Hangers, and Seismic Bracing

8.1 Pipe, Fittings, and Joints

8.1.1 Pipe, fittings, joints, control valves, check valves, waterflow and supervisory switches, main drains, pressure gauges, and hangers shall comply with Fire Protection PipingFire Protection Piping and SpecialtiesResolves to the current adopted revision.sync/fire-protection-piping.
8.1.2 The pipe materials and joining methods selected under Fire Protection PipingFire Protection Piping and SpecialtiesResolves to the current adopted revision.sync/fire-protection-piping shall be limited to the combinations NFPA 13 permits for the hazard classification, the pipe size, and the system pressure at each location.
8.1.3 Where CPVC pipe is selected under Fire Protection PipingFire Protection Piping and SpecialtiesResolves to the current adopted revision.sync/fire-protection-piping, its installation condition on this system shall be as indicated in the datasheet.
CPVC Installation Conditionradio
○ Concealed above ceilings and within walls only
○ Concealed and exposed within the listing conditions
NOTE A CPVC listing for sprinkler service is written around the sprinkler type, the hazard classification, and the exposure: exposed CPVC is listed only below a ceiling of the construction the listing names and only with quick-response sprinklers at the spacing the listing sets, so the exposed condition is a listing question before it is a preference. (8.1.4)
8.1.5 Where CPVC is exposed, the sprinklers, their spacing, and the ceiling construction shall be those the pipe listing requires for the exposed condition.
8.1.6 CPVC shall not be installed where its listing prohibits it, including any location where the ambient temperature can exceed the listed limit and any location where it would be exposed to a material named in the manufacturer's chemical compatibility advisory.
8.1.7 The Contractor shall issue the CPVC manufacturer's chemical compatibility advisory to every trade working near the piping before that trade begins work, and the general Contractor shall keep the named incompatible materials away from the piping.
NOTE Firestop sealants, cutting oils, thread sealants, insulation adhesives, and some aerosol products stress-crack CPVC on contact, and the failure appears months later as a leak in a concealed space rather than at the hydrostatic test. (8.1.8)

8.2 Hanging Policy

8.2.1 Hangers shall be listed for fire protection service and installed in accordance with NFPA 13 and Fire Protection PipingFire Protection Piping and SpecialtiesResolves to the current adopted revision.sync/fire-protection-piping.
8.2.2 The unsupported length between the end sprinkler on a branch line and the last hanger, the length of an armover, and the length of a sprig shall not exceed the limits NFPA 13 sets for the pipe size and the sprinkler type.
8.2.3 The hanger spacing along branch lines and mains shall not exceed the maximum spacing established under Fire Protection PipingFire Protection Piping and SpecialtiesResolves to the current adopted revision.sync/fire-protection-piping for the pipe material and size.
8.2.4 Hangers shall be located so that the reaction of a discharging sprinkler does not lift or rotate the branch line.
8.2.5 A hanger omitted near an end sprinkler to clear another trade's work shall be relocated to adequate structure, not eliminated.
NOTE The end-of-line rules exist because a discharging sprinkler pushes the pipe upward, and a branch line hung too far from its end sprinkler swings and can lift the sprinkler out of its listed position under the ceiling. (8.2.6)

8.3 Seismic Bracing Policy

8.3.1 Seismic bracing of the sprinkler system shall be provided where Seismic Design CategorySeismic Design CategoryParameterEach project supplies its own value.seismic-design-category requires it under NFPA 13 Chapter 18 as invoked by the adopted building code, as indicated in the datasheet.
Seismic Bracing of Sprinkler Pipingradio
○ Required
○ Not required
Derived — Seismic Design CategorySeismic Design CategoryParameterEach project supplies its own value.seismic-design-category under NFPA 13 Chapter 18 as invoked by the adopted building code (by default)
8.3.2 Where bracing is required, the seismic load basis shall be as indicated in the datasheet.
Seismic Load Basis for Sway Bracingradio
● NFPA 13 Chapter 18 seismic coefficient from the site short-period spectral acceleration
○ Engineered design under ASCE 7 Chapter 13
8.3.3 Where bracing is required, lateral and longitudinal sway bracing, branch line restraint, flexible couplings, and clearances at penetrations shall be provided in accordance with NFPA 13 Chapter 18, with the brace hardware, spacing, and attachments furnished under Fire Protection PipingFire Protection Piping and SpecialtiesResolves to the current adopted revision.sync/fire-protection-piping.
8.3.4 Seismic bracing calculations shall state the seismic coefficient used, the brace spacing, the load on each brace and attachment, and the listing of each brace assembly, and shall be submitted before bracing is installed.
NOTE The bracing requirement is keyed to the seismic design category the building code assigns to the site, not to a perception of local risk; Seismic Design Category C is common outside the recognized seismic regions and triggers the full bracing chapter. (8.3.5)
NOTE The NFPA 13 prescriptive method delivers a seismic coefficient from the site spectral acceleration and a set of tabulated brace capacities that the layout can be checked against without a structural engineer; an engineered design under ASCE 7 is used where the Authority Having Jurisdiction requires it, where the piping is attached to a structure the tables do not cover, or where the prescriptive method produces bracing the structure cannot carry. (8.3.6)

9 Sprinklers

9.1 Sprinkler Types

9.1.1 The sprinkler types permitted on the project shall be as indicated in the datasheet.
Sprinkler Types Permittedcheckbox
☑ Standard spray pendent
☑ Standard spray upright
☑ Standard spray sidewall
☐ Recessed pendent
☐ Concealed pendent with cover plate
☐ Flush pendent
☐ Extended coverage pendent
☐ Extended coverage upright
☐ Extended coverage sidewall
☐ Residential
☐ Institutional tamper-resistant and ligature-resistant
☐ Dry-type pendent and sidewall
☐ Attic sprinklers
☐ Window sprinklers
9.1.2 The sprinkler type installed in each area shall be as indicated on the fire protection drawings.
NOTE Each sprinkler type is listed for a coverage area, a spacing, a deflector position, and a range of ceiling constructions, so the type decides the sprinkler count and the branch line layout of every area it serves: (9.1.3)
  • A standard spray sprinkler covers up to 225 sq ft in light hazard and 130 sq ft in ordinary and extra hazard under a smooth flat ceiling, and less under obstructed or sloped construction.
  • An extended coverage sprinkler covers up to 400 sq ft within its listing and reduces the sprinkler count on a large flat ceiling, at the cost of stricter obstruction, clearance, and ceiling slope limits.
  • A sidewall sprinkler discharges away from the wall it is mounted on and serves a corridor or a small room without running pipe across the ceiling.
  • A recessed, flush, or concealed pendent sits partly or entirely above the ceiling line and is selected for appearance, with the cover plate of a concealed sprinkler carrying its own listed release temperature.
  • A residential sprinkler is listed for a wall-wetting pattern that keeps a fire in a dwelling unit from reaching flashover and is permitted only in the dwelling and sleeping units its listing covers.
  • An institutional sprinkler resists tampering and ligature attachment and is selected for the areas of a health care, detention, or behavioral facility where either is a hazard.
  • A dry-type sprinkler extends a wet system into a freezing pocket without a second system type, an attic sprinkler is listed for the slope and spacing of a combustible attic, and a window sprinkler provides the wetting that lets a glazed assembly stand in for a rated wall where the code permits it.
9.1.4 Sprinklers in dwelling units and sleeping units shall be of the type indicated in the datasheet.
Sprinkler Type in Dwelling and Sleeping Unitsradio
○ Residential sprinklers
○ Quick-response standard spray sprinklers
NOTE The building code requires either a residential or a quick-response sprinkler in a dwelling or sleeping unit; a residential sprinkler wets the walls high enough to prevent flashover and is designed to the flow its listing states, while a quick-response spray sprinkler is designed to the light hazard density and can be used where the ceiling construction or the obstruction condition falls outside the residential listing. (9.1.5)
9.1.6 Where residential sprinklers are selected, they shall be installed only within the ceiling construction, slope, and obstruction conditions their listing covers, and the design flow shall be the greater of the listed flow and the flow that produces the light hazard density.
9.1.7 Sprinklers shall not be installed in an application outside their listing.

9.2 Thermal Response

9.2.1 Sprinklers in light hazard areas shall be quick-response or residential sprinklers, as NFPA 13 requires.
9.2.2 The thermal response of sprinklers in ordinary and extra hazard areas shall be as indicated in the datasheet.
Thermal Response in Ordinary and Extra Hazard Areasradio
○ Standard response
○ Quick response
NOTE A quick-response sprinkler carries a response time index of 50 (m·s)^0.5 or less and opens earlier in the fire; a standard response sprinkler carries an index of 80 (m·s)^0.5 or more and opens later with more of the fire developed beneath it, so more sprinklers open and the design area assumption holds. (9.2.3)
NOTE Quick-response sprinklers in an ordinary hazard area buy earlier control and the design area reduction where the ceiling qualifies, at the cost of more sprinklers opening in a fast-growing fire than the design area assumed; standard response sprinklers hold the design area assumption in an area where the fuel load can grow a fire faster than early water can control it. (9.2.4)
9.2.5 Quick-response and standard response sprinklers shall not be mixed within a compartment, except where NFPA 13 expressly permits it.
9.2.6 Where the response class changes at a compartment boundary, the hydraulic calculation for a design area that spans the boundary shall use the more demanding assumption.

9.3 Temperature Ratings

9.3.1 The temperature rating classification of sprinklers in general areas shall be as indicated in the datasheet.
Temperature Rating Classification in General Areasselect
Ordinary (135°F to 170°F)
Intermediate (175°F to 225°F)
High (250°F to 300°F)
Extra High (325°F to 375°F)
Very Extra High (400°F to 475°F)
Ultra High (500°F to 575°F)
9.3.2 The temperature rating in each general area shall be selected for the maximum ceiling temperature that area reaches, in accordance with the temperature rating table of NFPA 13.
9.3.3 Sprinklers near heat sources shall carry the rating NFPA 13 assigns to the location, including intermediate rating within the stated distances of heating unit outlets, under skylights, in unventilated concealed spaces and attics, and above commercial cooking appliances, and high rating within the stated distances of high-temperature equipment.
9.3.4 The locations at which a rating other than the general area rating applies shall be as indicated on the fire protection drawings.
NOTE A rating set too close to the ceiling temperature opens the sprinkler on a hot day, and a rating set too high delays water while the fire grows; the ordinary rating is the one that fits a ceiling that never exceeds 100°F, and every other rating follows from a measured or expected ceiling temperature rather than from a preference. (9.3.5)
9.3.6 The cover plate of a concealed sprinkler shall carry the release temperature its listing pairs with the sprinkler behind it.
9.3.7 The frame color or bulb color of each sprinkler shall be the color code NFPA 13 assigns to its temperature rating, and shall not be obscured by the finish.

9.4 K-Factor

9.4.1 The minimum nominal K-factor of standard spray sprinklers on the project shall be as indicated in the datasheet.
Minimum Nominal K-Factor of Standard Spray Sprinklersrange
gpm/psi^0.5
2.84.25.6811.214
9.4.2 The nominal K-factor of the sprinklers in each area shall be as indicated on the fire protection drawings, and shall be not smaller than the minimum NFPA 13 sets for the hazard classification and design density of that area.
NOTE The K-factor relates flow to pressure at the sprinkler orifice, and a larger orifice delivers the design density at a lower pressure, which on a marginal supply is the difference between a system that calculates and one that needs a pump; NFPA 13 requires the larger orifices in extra hazard and at the higher densities because a small orifice at high pressure produces a fine spray that the fire plume carries away. (9.4.3)
9.4.4 Sprinklers with a nominal K-factor smaller than 5.6 shall be installed only where NFPA 13 permits them and shall be provided with the strainer or the piping arrangement NFPA 13 requires for a small orifice.
9.4.5 The hydraulic calculations shall use the nominal K-factor of the sprinkler listed on the product data, and a sprinkler of a different K-factor shall not be substituted after the calculations are accepted.

9.5 Finish and Corrosion Resistance

9.5.1 The finish of sprinklers, escutcheons, and cover plates in finished ceiling areas shall be as indicated in the datasheet.
Sprinkler and Escutcheon Finish in Finished Ceiling Areasselect
Natural brass
Chrome plated
White polyester coating
Black polyester coating
Custom color polyester coating matched to the ceiling
9.5.2 The finish of sprinklers in unfinished and utility areas shall be as indicated in the datasheet.
Sprinkler Finish in Unfinished and Utility Areasselect
Natural brass
Chrome plated
White polyester coating
Black polyester coating
9.5.3 Where the finish differs between areas of the same finish class, the finish of each area shall be as indicated on the fire protection drawings.
9.5.4 Sprinklers in corrosive locations shall be of the corrosion-resistant construction indicated in the datasheet.
Corrosion-Resistant Sprinklers in Corrosive Locationsselect
Listed wax coating
Listed lead-free polyester coating
Listed fluoropolymer coating
Stainless steel sprinklers
Not applicable, no corrosive locations
9.5.5 The locations classified as corrosive shall be as indicated on the fire protection drawings.
9.5.6 Only a factory-applied, listed finish or coating shall be present on a sprinkler, and no paint, coating, or ceiling finish shall be applied to a sprinkler, an operating element, a deflector, or a cover plate in the field.
NOTE A wax coating is the oldest corrosion protection and softens in a warm location, a polyester coating holds up in most chemical and coastal atmospheres, a fluoropolymer coating resists a wider range of chemicals, and a stainless steel sprinkler is used where any coating would be attacked; each is a listed construction, and the listing rather than the atmosphere name decides which one fits a location. (9.5.7)
NOTE A field-painted sprinkler is a disabled sprinkler, because paint bridges the operating element and the frame and holds the sprinkler closed past its rating; a painted sprinkler found at inspection is replaced, not cleaned. (9.5.8)

9.6 Sprinkler Position and Coverage

9.6.1 Sprinkler spacing, the coverage area per sprinkler, the deflector distance below the ceiling, and the clearance from obstructions shall comply with NFPA 13 for the sprinkler type, the hazard classification, and the ceiling construction of each area, and shall not exceed the limits of the sprinkler listing.
9.6.2 Sprinklers shall be provided throughout the building, including concealed combustible spaces, except in the locations where NFPA 13 permits sprinklers to be omitted.
9.6.3 The concealed spaces and other locations in which sprinklers are omitted under NFPA 13 shall be as indicated on the fire protection drawings.
9.6.4 A clearance of not less than 18 in. shall be maintained between the deflector of a standard spray sprinkler and the top of storage, shelving, or any other object below it.
9.6.5 The Contractor shall state the 18 in. clearance on the general information sign at the riser and in the operation and maintenance manual, so that the Owner is informed of it before the building is occupied.
NOTE The clearance lets the discharge pattern develop before it strikes anything, and it is the rule most often broken after occupancy, when shelving goes in under sprinklers that were positioned for an empty room. (9.6.6)
9.6.7 Where a sprinkler is exposed to mechanical damage, it shall be protected by a listed guard, and the locations requiring guards shall be as indicated on the fire protection drawings.
9.6.8 Sprinkler positions in finished ceilings shall be centered in the ceiling tile or aligned with the ceiling pattern as the finished ceiling layout requires, within the position the listing and NFPA 13 permit.

9.7 Flexible Sprinkler Connections

9.7.1 Whether flexible sprinkler hose connections are permitted between the branch line and a ceiling sprinkler shall be as indicated in the datasheet.
Flexible Sprinkler Hose Connectionsradio
○ Permitted within the listing
○ Not permitted
NOTE A flexible connection lets the sprinkler be placed in the ceiling tile after the branch line is hung and absorbs the offset between the branch line and the tile center without a fabricated drop; it adds a friction loss that the calculation has to carry, a bracket that has to be attached to the ceiling grid as the listing requires, and a bend radius that is violated when the hose is forced into a short offset. (9.7.2)
9.7.3 Where flexible connections are permitted, they shall be listed to UL 2443, and where the datasheet requires FM Approval they shall additionally be approved to FM 1637.
9.7.4 Each flexible connection shall be installed within its listed length, minimum bend radius, and number of bends, with the bracket the listing requires attached to the ceiling grid or structure, and with the hose supported so that no weight bears on the sprinkler.
9.7.5 The equivalent length of each flexible connection shall be included in the hydraulic calculations at the value published in its listing.
9.7.6 Where seismic bracing is required, flexible connections shall be installed in accordance with the provisions NFPA 13 Chapter 18 makes for them.

10 Riser, Valves, and Zoning

10.1 Wet-Pipe Riser Arrangement

10.1.1 The riser of each wet-pipe system shall be arranged as indicated in the datasheet.
Wet-Pipe Riser Arrangementradio
○ Alarm check valve with retard chamber and trim
○ Riser check valve with vane-type waterflow switch
○ Backflow prevention assembly serving as the riser check valve, with vane-type waterflow switch
NOTE An alarm check valve detects flow by the lift of its clapper and can drive a water motor gong with no electric power, at the cost of a retard chamber and trim that need periodic service; a riser check valve with a vane switch detects flow electrically and is the simpler assembly where the building has a fire alarm system; and where a backflow prevention assembly is already required on the supply, NFPA 13 permits it to serve as the riser check valve so that a third check is not stacked into the riser. (10.1.2)
10.1.3 The riser location shall be as indicated on the fire protection drawings.
10.1.4 The riser nominal size shall be as indicated on the fire protection riser diagram.
10.1.5 Each riser shall be provided with a listed indicating control valve at its connection to the supply, supervised open, together with the check valve, waterflow device, main drain, and pressure gauges furnished under Fire Protection PipingFire Protection Piping and SpecialtiesResolves to the current adopted revision.sync/fire-protection-piping.
10.1.6 The main drain shall be sized under Fire Protection PipingFire Protection Piping and SpecialtiesResolves to the current adopted revision.sync/fire-protection-piping for the riser size and shall discharge where the full drain flow can be received without damage.
10.1.7 Where the riser is a combined sprinkler and standpipe riser, the standpipe portion shall comply with Standpipe SystemsStandpipe SystemsResolves to the current adopted revision.sync/standpipe-systems, and each sprinkler connection from the riser shall be made through a floor control assembly under this standard.

10.2 Floor and Zone Control Assemblies

10.2.1 The sprinkler zoning arrangement shall be as indicated in the datasheet.
Sprinkler Zoning Arrangementradio
○ Single system without floor or zone control assemblies
○ Floor control assembly at each floor
○ Zone control assemblies
10.2.2 Where zone control assemblies are selected, the extent of each zone shall be as indicated on the fire protection riser diagram.
10.2.3 A floor control assembly shall be provided on each floor of a high-rise building and wherever else NFPA 13 or the adopted building code requires one, whatever the datasheet selects.
NOTE A control assembly per floor or zone lets one portion of the building be impaired for a tenant fit-out or a repair without shutting off the rest, and it identifies the floor of a waterflow at the fire alarm panel; the cost is a valve, a switch, and a test connection at each assembly and a shaft or closet to house them. (10.2.4)
10.2.5 Each floor or zone control assembly shall include the components indicated in the datasheet.
Floor and Zone Control Assembly Componentscheckbox
☑ Listed indicating control valve with supervisory switch
☑ Check valve
☑ Vane-type waterflow switch
☑ Combined test-and-drain assembly with sight glass
☑ Pressure gauge on the system side
☐ Pressure-reducing valve where the static pressure exceeds 175 psi
10.2.6 The control assembly for each floor or zone shall be located where it is accessible without entering a tenant space, as indicated on the fire protection drawings.
10.2.7 The test connection at each control assembly shall discharge to a drain sized to receive the full test flow without overflowing.

10.3 Inspector's Test Connection

10.3.1 An inspector's test connection shall be provided at the hydraulically most remote point of each system, or at each floor or zone control assembly where the test-and-drain assembly is selected there, with an orifice equivalent to the smallest sprinkler on the system.
10.3.2 The inspector's test discharge shall be arranged as indicated in the datasheet.
Inspector's Test Discharge Arrangementselect
To the exterior of the building
To a drain sized to receive the full test flow
Through a sight test connection to a drain
NOTE An exterior discharge lets the tester see the flow without a drain but freezes shut in a cold climate and stains the wall it discharges onto; a drain discharge needs a drain sized for the flow of one sprinkler; and a sight glass on a drain discharge shows the flow indoors, which is why the combined test-and-drain assembly with a sight glass is the arrangement most often installed at a floor control assembly. (10.3.3)
10.3.4 The inspector's test connection shall be accessible without a ladder from an area the Owner's staff can reach, and its valve shall be identified as the inspector's test.

10.4 Backflow Prevention

10.4.1 Where the water utility or the adopted plumbing code requires backflow prevention between the sprinkler system and the potable supply, the assembly shall be provided under Backflow PreventionBackflow PreventionResolves to the current adopted revision.sync/backflow-prevention and shall be listed for fire protection service.
NOTE The assembly type shall be confirmed with the water utility and the Authority Having Jurisdiction before procurement, because a reduced pressure principle assembly on a supply that a double check assembly would have satisfied throws away 10 psi or more of pressure the sprinkler system needed. (10.4.2)
10.4.3 The assembly shall be installed with the clearances and the test cocks its annual certification requires, and shall be arranged so that its forward-flow test can be conducted at the system demand.

11 Alarm and Supervisory Provisions

11.1 Waterflow Alarm

11.1.1 Each wet-pipe system shall be provided with a waterflow alarm device that initiates an alarm within 90 seconds of a sustained flow equal to or greater than the flow from one sprinkler, in accordance with NFPA 13 and NFPA 72.
11.1.2 The waterflow device on each riser and control assembly shall be furnished under Fire Protection PipingFire Protection Piping and SpecialtiesResolves to the current adopted revision.sync/fire-protection-piping, with its retard set under that standard, and shall be connected to the fire alarm system under Fire Alarm SystemsFire Alarm SystemsResolves to the current adopted revision.sync/fire-alarm-systems.
11.1.3 The local waterflow alarm at the building shall be as indicated in the datasheet.
Local Waterflow Alarmradio
○ Electrically operated alarm from the fire alarm system
○ Water motor gong
○ Water motor gong and electrically operated alarm
NOTE A water motor gong is driven by the water in the alarm line of an alarm check valve and sounds with no electric power, so it needs an alarm check valve on the riser; an electrically operated alarm is driven by the fire alarm control unit from the waterflow switch and is the local alarm on a riser arranged with a vane switch. (11.1.4)
11.1.5 Where the riser arrangement selected has no alarm check valve, a water motor gong shall not be selected for that riser.

11.2 Valve Supervision

11.2.1 Every valve controlling water to any portion of the sprinkler system, including the riser control valve, each floor and zone control valve, and the isolation valves of the backflow prevention assembly, shall be electrically supervised in the open position by a supervisory switch connected to the fire alarm system, as NFPA 13, NFPA 72, and the adopted building code require.
11.2.2 The supervisory switch shall initiate a supervisory signal within two turns of the handwheel or one-fifth of the valve travel from the fully open position, whichever is less.
11.2.3 The Contractor shall provide the fire alarm Contractor with the location and type of every supervised valve and every waterflow device before the fire alarm shop drawings are prepared.
NOTE A branch riser butterfly valve without a supervisory switch is the supervision deficiency most often written at acceptance, and it is found because the sprinkler and fire alarm shop drawings were prepared from different valve counts. (11.2.4)

11.3 Identification Signs

11.3.1 A permanent hydraulic design information sign shall be affixed at each riser and at each floor or zone control assembly served by a separate calculation, stating the location of the design area, the design density and area, the required flow and pressure at the base of the riser, the hose stream allowance, the total demand and its duration, and the K-factor and thermal response of the sprinklers in the design area.
11.3.2 A permanent general information sign shall be affixed at each riser, stating the information NFPA 13 requires, including the hazard classification of each area served, the presence and type of any antifreeze solution, the location of auxiliary drains and low points, the presence of any pressure-reducing valve, and the 18 in. clearance below sprinklers.
NOTE The hydraulic sign is what a later designer checks a tenant change against, and the general information sign is what an inspector reads before draining or refilling the system; a sign that does not match the accepted calculations misleads both. (11.3.3)
11.3.4 Each riser, floor control assembly, and zone control assembly shall be identified with the designation used on the working drawings and on the fire alarm annunciator.

12 Installation

12.1 Routing and Deviations

12.1.1 Sprinkler piping shall be routed, sized, and arranged as shown on the working drawings approved by the Authority Having Jurisdiction.
12.1.2 A deviation from the approved working drawings in pipe routing, pipe size, or sprinkler position shall be documented by a revised submittal or by the Engineer of Record's written acceptance and the Authority Having Jurisdiction's concurrence before the affected work is installed.
NOTE A relocated sprinkler or a resized pipe changes the hydraulic balance of the design area and the coverage of the sprinklers around it, which is why a field change that looks harmless is checked against the calculation before it is made. (12.1.3)
12.1.4 Sprinkler piping shall be arranged to drain to the main drain or to auxiliary drains, and trapped sections that cannot drain shall be provided with auxiliary drains under Fire Protection PipingFire Protection Piping and SpecialtiesResolves to the current adopted revision.sync/fire-protection-piping.
12.1.5 Penetrations of fire-resistance-rated assemblies shall be sealed with a firestop system listed for the pipe material and the assembly rating, in accordance with FirestoppingFirestoppingResolves to the current adopted revision.sync/firestopping, and the firestop material shall be one the pipe manufacturer's compatibility advisory permits where CPVC is used.

12.2 Sprinkler Installation

12.2.1 Sprinklers shall be installed with the wrench the manufacturer lists for the sprinkler, and a sprinkler installed with a wrench that bears on the operating element or the deflector shall be replaced.
12.2.2 A sprinkler that has been dropped, struck, or overheated, or that shows a damaged bulb, a bent deflector, or a cracked cover plate, shall be replaced rather than installed.
12.2.3 Sprinklers shall be installed after the piping serving them has been flushed, and shall be protected from paint, overspray, ceiling finish, and debris until the finish trades have completed work in the area.
12.2.4 Where a sprinkler must be installed before finish work is complete, it shall be protected by a listed protective cap that the heat of a fire removes, and every cap shall be removed before the system is accepted.
12.2.5 Escutcheons, cover plates, and recessed housings shall be the listed components of the sprinkler they serve.
NOTE A protective cap left on a sprinkler after acceptance defeats the sprinkler under it, and a cap count at the acceptance inspection is the check that finds it. (12.2.6)

12.3 Cold Weather Work

12.3.1 Solvent-cement joints in CPVC, grooved gaskets, and the other joints and materials whose listing sets a minimum installation temperature shall not be installed below that temperature, and the Contractor shall heat the work area or defer the work.
12.3.2 The cure time of a solvent-cement joint before pressurization shall be the cold-weather cure time published for the cement where the ambient temperature is below the published threshold.

13 Testing

13.1 Flushing

13.1.1 The underground supply shall be flushed under Underground Fire Service MainsUnderground Fire Service MainsResolves to the current adopted revision.sync/underground-fire-service-mains before it is connected to the riser.
13.1.2 The aboveground piping shall be flushed at a flow not less than the total system demand, or at the highest flow the supply can deliver, through open connections at the ends of the mains and cross mains until the discharge runs clear, before sprinklers are installed.
NOTE Cutting chips, scale, and construction debris travel to the sprinkler orifices, and a single blocked sprinkler in the design area breaks the density the calculation depends on, which is why the flush precedes the sprinklers and is recorded on the certificate. (13.1.3)

13.2 Hydrostatic Test

13.2.1 The aboveground piping shall be hydrostatically tested for 2 hours with no leakage and no drop in gauge pressure, at the test pressure indicated in the datasheet.
Hydrostatic Test Pressurerange
psi
200225250275300325350375400
Derived — the maximum system static pressure: 200 psi where that pressure does not exceed 150 psi, otherwise 50 psi above it, per NFPA 13 (by default)
13.2.2 The test shall be applied to the whole system at once, or to portions separated by valves qualified for pressure isolation, and every joint that will be concealed shall be under test before it is concealed.
13.2.3 The test pressure shall be measured at the lowest point of the portion under test, so that the margin above the working pressure holds at every elevation.
13.2.4 Components whose rating is below the test pressure shall be isolated or removed before the test and reinstalled after it.
13.2.5 Where CPVC piping is tested below the temperature its listing names, the test pressure shall not exceed the listed cold-temperature test pressure, and the solvent-cement cure time shall have elapsed before the system is pressurized.
13.2.6 Piping that leaks under test shall be repaired by remaking the joint, and the portion shall be retested at the Contractor's expense.

13.3 Alarm and Supervisory Device Test

13.3.1 Each waterflow device shall be tested by opening the inspector's test connection it serves, and the time from the opening of the connection to the alarm at the fire alarm control unit shall be recorded and shall not exceed 90 seconds.
13.3.2 Each water motor gong shall be tested by flowing the inspector's test connection and shall sound within the time NFPA 13 allows.
13.3.3 Each supervisory switch shall be tested by operating the valve toward closed, and the supervisory signal shall be received at the fire alarm control unit within the travel this standard requires, after which the valve shall be returned to fully open and confirmed open.
13.3.4 Where a low point or auxiliary drain, an air vent, or a pressure-reducing valve is installed, its operation shall be demonstrated as part of the acceptance test.

13.4 Main Drain and Forward-Flow Tests

13.4.1 A main drain test shall be conducted at each riser with all supply valves open, and the static and residual pressures shall be recorded on the certificate as the baseline for the annual NFPA 25 test.
13.4.2 The forward-flow test of the backflow prevention assembly shall be as indicated in the datasheet.
Backflow Prevention Assembly Forward-Flow Testradio
○ Forward-flow test at the total system demand through the assembly
○ Not applicable, no backflow prevention assembly on the supply
Derived — whether a backflow prevention assembly is installed on the sprinkler system supply (by default)
13.4.3 Where a backflow prevention assembly is installed, it shall be forward-flow tested at the total system demand, including the hose stream allowance, through a test connection sized for that flow, and the pressure loss across the assembly shall be recorded and compared with the loss used in the hydraulic calculations.
NOTE A main drain residual well below the design supply, or an assembly loss above the calculated loss, points to a partly closed valve, a supply that has declined since the flow test, or an assembly loss curve that was misread, and each is corrected before acceptance rather than discovered at the first annual test. (13.4.4)

13.5 Acceptance Witnesses and Records

13.5.1 The acceptance tests shall be witnessed by the parties indicated in the datasheet.
Acceptance Test Witnessescheckbox
☑ Authority Having Jurisdiction
☐ Fire department of jurisdiction
☐ Engineer of Record
☐ Owner's representative
☐ Insurance carrier representative
☐ Commissioning authority
13.5.2 The Contractor shall schedule the acceptance test with the Authority Having Jurisdiction not less than 10 working days before the test, with the system complete, the water supply at design pressure, and the deficiencies from any preliminary inspection corrected.
13.5.3 The Contractor's Material and Test Certificate for Aboveground Piping shall be completed for each system, signed by the Contractor and by each witness, and included in the closeout submittals.
13.5.4 The system shall not be placed in service, and the fire alarm system shall not be released from test, until the Authority Having Jurisdiction has accepted the system.
NOTE The certificate is the permanent record of the system's condition at installation and the baseline against which every later NFPA 25 result is compared, so a field left blank on it is a gap in the Owner's record for the life of the building. (13.5.5)

14 Inspection, Testing, and Maintenance After Acceptance

14.1 Whether the first year of inspection, testing, and maintenance is included in the Contract shall be as indicated in the datasheet.
First-Year Inspection, Testing, and Maintenanceradio
○ Quarterly and annual NFPA 25 inspection and testing for the first year included in the Contract
○ Not included
14.2 The Contractor shall include in the operation and maintenance manual the NFPA 25 inspection, testing, and maintenance schedule for the system, including the quarterly waterflow alarm test, the annual main drain test, the annual inspection of sprinklers, hangers, and bracing, the five-year internal assessment of the piping, and the sprinkler sampling intervals for each response class installed.
14.3 The manual shall describe the impairment procedure, including notification of the fire department, the supervising station, and the insurance carrier, the fire watch or alternative protection while the system is impaired, and the restoration steps, in accordance with NFPA 25.
14.4 An inspection tag stating the date of the acceptance test shall be attached at each riser.

15 Delivery, Storage, and Handling

15.1 Sprinklers shall be delivered and stored in their original packaging, indoors, in a dry location where the temperature does not approach the rating of any sprinkler, and shall be handled so that no operating element, deflector, or cover plate is struck or bent.
15.2 Pipe, fittings, valves, and devices shall be delivered, stored, and handled under Fire Protection PipingFire Protection Piping and SpecialtiesResolves to the current adopted revision.sync/fire-protection-piping.
15.3 Sprinklers that have been exposed to a temperature above their rating, submerged, or subjected to impact in storage shall not be installed.
15.4 Materials damaged in transit, storage, or handling shall be replaced rather than repaired unless the Engineer of Record accepts a specific repair in writing.

16 Warranty

16.1 The Contractor shall warrant the sprinkler installation, including every sprinkler, valve, device, and sign furnished under this standard, against defects in materials and workmanship and against leakage under the system working pressure for the period indicated in the datasheet, measured from the date of substantial completion.
Sprinkler Installation Warranty Periodrange
years
1235
16.2 Where a listed component carries a manufacturer's warranty longer than the period in the datasheet, the Contractor shall assign that warranty to the Owner, and the longer period shall govern for that component.
16.3 Where the contract documents state a longer warranty period than the datasheet, the longer period shall govern.
16.4 The Contractor shall respond to a warranty call that impairs the system within the time indicated in the datasheet, and shall restore the system or provide the alternative protection the impairment procedure requires within that time.
Warranty Response Time for an Impairmentrange
hours
2482448
16.5 The Contractor shall place the fire alarm system in test with the supervising station before warranty work begins and shall return it to service when the work is complete.
16.6 The Contractor's cost of a warranty correction shall include the repair of finishes, ceilings, and contents damaged by the defect or by gaining access to it.
16.7 Work performed under this warranty shall itself be warranted for a full new term equal to the original period measured from the date the correction is completed, or for the remainder of the original period, whichever ends later.

17 Spare Parts

17.1 The Contractor shall furnish a spare sprinkler cabinet at each riser room, stocked with not fewer than the number of sprinklers indicated in the datasheet, representing every type, orifice, temperature rating, and finish installed on the system, together with a wrench for each sprinkler type.
Spare Sprinkler Cabinet Quantityrange
sprinklers
61224
Derived — the total number of sprinklers installed on the system, per NFPA 13: 6 for 300 or fewer, 12 for 301 to 1,000, and 24 for more than 1,000 (by default)
17.2 The cabinet shall be located where the temperature does not exceed 100°F, and a list of the sprinklers it contains, with the type, orifice, rating, and finish of each, shall be posted inside its door.
17.3 The Contractor shall deliver the other spare parts indicated in the datasheet to the Owner before the system is accepted, and shall obtain a signed receipt for them together with the cabinet.
Spare Parts to Be Furnishedcheckbox
☐ Spare cover plates for each concealed sprinkler finish
☐ Spare escutcheons for each recessed sprinkler finish
☐ Spare gaskets and trim parts for the alarm check valve
☐ Spare sight glass for each test-and-drain assembly type
17.4 Spare parts shall be the same make and model as the installed items and shall be delivered in their original unopened packaging.
NOTE An understocked or missing spare cabinet is a deficiency written at the acceptance inspection and at every annual inspection after it, and a sprinkler that opens with no matching spare on hand leaves that area unprotected until one is procured. (17.5)

Edit this page

SynC Standards are reference material provided for informational purposes only and as a guide. They are not engineering, architectural, or legal advice and are not a substitute for the judgment of a licensed design professional. It is the responsibility of the user to determine the applicability of any standard to a specific project and to verify all requirements against the governing codes, manufacturer data, and project conditions. SynC does not render professional services and forms no professional relationship by publishing this content. Provided "as is," without warranty of any kind, including fitness for a particular purpose. See our Terms of Use for the complete terms. Moderation log.

This standard is published by SynC and licensed under Creative Commons Attribution-ShareAlike 4.0. You may share and adapt it, including commercially, provided you give credit, link to the license, indicate any changes, and license your adaptations under the same terms. Keep the attribution and notice below with any copy — it includes the warranty disclaimer the license requires you to retain.

Attribution & reuse notice — keep this with any copy:
"Wet-Pipe Fire Sprinkler Systems." SynC Standards. Licensed under CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0/). Source: https://synergyinconstruction.com/wiki/sync/wet-pipe-fire-sprinkler-systems — reference material only; not professional engineering advice and provided without warranty. Verify against governing codes and have a licensed professional review before use.