Automatic Sprinkler SystemsFET 112 Fire Protection SystemsObjective #2

Automatic Sprinkler Systems

Automatic Sprinkler SystemFor fire protection purposes, an integratedsystem of underground and overhead pipingdesigned in accordance with fire protection engineering standardsusually activated byheat and discharges water over the fire area.

History and Development of Automatic Sprinkler SystemsEarly sprinkler systems involved the use of steel pipe with drilled holes or perforations provided along the length of pipeThis type of system involved a manually operated water supplyCorrosion, plugged holes, poor distribution of water onto the fire

History and Development of Automatic Sprinkler SystemsThe concept for the use of a heat-actuated device dates back to approximately 1860, but it was not until 1875 that this concept was incorporated into a deviceHenry Parmelee is given credit for the first automatic sprinklerBrass Cap soldered over a perforated distributor designed to screw onto a nipple

NFPA 1995 report: U.S. Experience with SprinklersNFPA has no record of a fire killing more than two people in a completely sprinklered public assembly, educational, institutional, or residential building where the system was properly operating.

Automatic Sprinkler SystemDetects a fireSounds an alarmControls or extinguishes the fireEnhances life safetyReduces severity of lossMinimizes business interruptionMost reliable and effective of all fire protection devices / systems

Automatic Sprinkler SystemCommon MisconceptionsHeat from lighting a cigarette can activate the systemWhen one goes off, they all go offEasily activated by accidentWill cause severe water damageLeaks and drips are common problemsNot cost effective

Automatic Sprinkler SystemWhy Do They Fail?Maintenance35%Occupancy14%Inadequate Water10%Partial Protection 8%Obstructions 8%Impairments 8%Construction6%Other Causes11%National FireProtection Association

Automatic Sprinkler SystemCROSSMAINBULK MAIN(RISER)WATERMOTORALARMFIREDEPT.CONNECTIONMAIN DRAINCONNECTIONWATER SUPPLYALARM VALVEO.S. & Y. GATE VALVE TO CONTROL WATERSUPPLY TO SYSTEMAUTOMATICSPRINKLERSINSPECTORSTESTCONNECTIONBRANCHLINES

Automatic Sprinkler SystemDesign ConsiderationsOccupancy / storage / hazardsEnvironmentBuilding constructionSize / height of buildingSpecial featuresLocationWater supply

Occupancy ClassificationsLight Hazard: Low Combustibility / low quantity of contentsOrdinary Hazard Group 1: Combustibility is low, quantity is moderate, moderate rate of heat releaseExamples - parking garages / bakeries / canneries / laundriesOrdinary Hazard Group 2: Combustibility / quantity is moderate to high, heat release moderate to highExamples - dry cleaners / printing / wholesale -retail sales

Occupancy ClassificationsExtra Hazard Group 1: Combustibility and quantity very high, probability of rapidly developing fires with high heat release, little or no flammable / combustible liquidsExamples - feed mills / paper - wood - rubber products manufacturerExtra Hazard Group 2: Same as group 1 with moderate to substantial amounts of flammable / combustible liquids or extensive shielding of combustiblesExamples - woodworking with flammable finishing, flammable liquids spraying, flow coating, mobile or modular housing manufacturers

Automatic Sprinkler SystemTypes of SystemsWet pipe systemDry pipe systemDeluge systemPreaction systemAntifreeze system (loop)

Wet Pipe SystemSystem entirely filled with waterHeat opens system and water begins to flow immediatelyFlowing water causes an alarm to soundWater controls or extinguishes the fireNo action required to restore system except replacing activated sprinklersMust be non-freezing locations

Wet Pipe SystemRISERSYSTEMPRESSURESUPPLYPRESSUREMAINDRAINSUPPLY SIDEO.S. & Y.VALVETO ALARMPILOTVALVECLAPPER(CLOSED)SYSTEMSIDE

Wet Pipe System

Dry Pipe SystemUsed in unheated or artificially cooled areas (40 F or less)System filled with air or nitrogen under pressure Sprinklers opening releases air or nitrogen causing dry pipe valve to trip (open)System fills with water and flows out opened sprinklersFollowing activation system must be drained and reset

Dry Pipe Sprinkler System (Set)

Dry Pipe Sprinkler System (Tripped)AIR PRESSUREGUAGEFILLER CUPFOR WETSEATSYSTEM2 DRAINO.S. & Y. VALVEWATERPRESSUREGUAGETOALARMOPENCLAPPER

Dry Pipe ValveSetTripped

Dry Pipe System

Dry Pipe SystemQuick Opening DevicesAccelerator: Sprinkler opening causes air pressure to drop. Accelerator activates, sending air pressure under clapper causing dry pipe valve to tripExhauster: Sprinkler opening causes exhauster to open, allowing air to escape to atmosphere. Dry pipe valve trips quickerRequired if system capacity exceeds 500 gallons or time for water flow to test connection exceeds 60 seconds.

Quick Opening DeviceAIRAIRSEATWATERWATERSEATACCELERATORRESTRICTED ORIFICEINTERMEDIATE CHAMBERTOALARMAIRWATERVALVEBALL DRIPCLAPPERFLEXIBLEDIAPHRAGMAccelerator

Quick Opening Device (Exhauster)RISERSYSTEMAIRRESTRICTED ORIFICETOATMOSPHERE4040

Deluge SystemSpecial use systemAll sprinklers are openValve to system is opened by a heat / smoke detection systemWater flows from all sprinklers upon activationRequires draining / resetting following activationValve must be in heated location

Deluge SystemAUTOMATICOR MANUALACTIVATINGDEVICEOPENSPRINKLERMAINDRAINSUPPLYPRESSUREATMOSPHERICPRESSURETO ALARM

Deluge System

Preaction SystemDeveloped for properties highly susceptible to water damageRequires 2 activations for water dischargePiping is filled with air/ sprinklers closedA fire detection system opens valve flooding system with water and sounding an alarmWater does not flow until heat opens a sprinklerMay allow time for manual fire suppressionSystem requires draining / resetting

Preaction SystemAUTOMATICOR MANUALACTIVATINGDEVICECLOSEDSPRINKLERMAINDRAINSUPPLYPRESSUREATMOSPHERICPRESSURETO ALARM

Preaction System

Review of theThree Types ofPreaction Systems

Non-InterlockedPreaction systemsDesigned so the Deluge Valve will open when EITHER the detection system operates OR a loss of pneumatic (air) pressure in the sprinkler system occursWhen the Deluge Valve opens, water will flow into the sprinkler piping and out of any open sprinklers and any other opening on the system.In the event of non-operation of the release system, the system will operate as a dry system.

Single-InterlockedPreaction systems (most common)Activation of a fire detection system will fill the system piping with waterUsed where:It is desirable to have water available at the sprinkler when the sprinkler operatesThe sprinkler piping is subject to:DamageFreezing conditionsAccidental water discharge must be minimized

Double-InterlockedPreaction systemsActivation of BOTH the detection system and operation of an automatic sprinkler are necessary to cause discharge of water in the hazard areaActivation of one only will not cause the valve to openDetection only alarm conditionSprinkler activation loss of air pressure

Antifreeze System (Loop)Used in small unheated area such as a loading dockConnected to a wet pipe systemCapacity of antifreeze system should not exceed 40 gallonsMust meet local / state health regulationsSolution must meet proper type / mixture

Antifreeze System (Loop) (cont.)Heat opens the sprinklers releasing antifreeze followed by water from wet pipe systemSystem requires restoration following the activationAnnual testing of solution required

Antifreeze System (Loop)SPRINKLERUNHEATEDAREADRAIN VALVECHECK VALVEHEATEDAREAVALVEWETPIPESYSTEMFILLING CUPWATERANTI-FREEZESOLUTION

Residential Sprinkler Systems

History Residential SystemsAutomatic Sprinkler Systems have been successfully used to protect various occupancies, including commercial and industrial buildings for over 100 yearsHowever, a residence has historically been the place where most people dieIn 1973, a report of the National Commission on Fire Prevention and Control titled, America Burning brought to light this fact80% of fire deaths were in the home

Residential InstallationAlthough increasing, it is estimated that less than 3 percent of the one- and two-family homes in the United States have them installed

Residential Sprinkler SystemsHandout of NFPA 13R Standard for the Installation of Sprinkler Systems in Residential Occupancies up to and Including Four Stories in HeightNFPA 13D Standard for the Installation of Sprinkler Systems in One- and Two-Family Dwellings and Manufactured Homes

Residential Sprinkler Systems (cont.)NFPA 13R addresses cost-effective sprinkler protection with LIFE SAFETY as its PRIMARY GOAL and PROPERTY PROTECTION as a SECONDARY GOALNFPA 13R provides a high, but not an absolute, level of life safety and a somewhat lesser degree of property protection

Residential Sprinkler Systems (cont.)A sprinkler system designed and installed with NFPA 13R is expected to prevent flashover (total involvement) in the room of fire origin, where sprinklered, and to improve the chance for occupants to escape or be evacuatedCriteria was developed by Underwriters Laboratory (UL) and Factory Mutual Research Corporation (FMRC) during actual fire tests

Residential Sprinkler Systems (cont.)The main differences between a commercial sprinkler system (NFPA 13) and a residential sprinkler system is the sprinkler heads and the incoming service arrangementResponse Time vs. Conductivity of the head

Residential Sprinkler HeadsClassified as Fast Response Sprinkler HeadsAlso, the spray from the residential sprinkler heads must wet the walls of the fire test chamber within their area of coverage to at least 18 inches from the ceiling

Water Spray Systems

Water Spray SystemsThe term water spray refers to water that is discharged from specially designed nozzles or devices to produce a predeterminedPatternParticle sizeVelocityDensityThe use of these designations cannot be taken as an indication of any specific discharge pattern or spray characteristics of the nozzle

Water Spray Systems (cont.)Water Spray Systems are also called Water Fog SystemsThese systems are typically designed to protect a specific piece of equipment with surface coverageIn addition, water spray systems are usually of the deluge type of system

Water Spray NozzlesSpray nozzles are not equipped with fusible operating elementsDischarge from water spray nozzles differ from standard sprinklers in the following ways:Pattern from spray nozzles may be ellipticalWater spray is forcefully directed onto the object or surface being protectedThe nozzle spray must overcome wind and draft conditionsThe required design density

Advantages of Wet SystemsSystem simplicityRelative low installation and maintenance expenseEase of modificationShort down time following a fire

Disadvantages of Wet SystemsThis type of system is not suited for subfreezing environmentsNot practical where piping is potentially subject to severe impact damage

Advantages of Dry SystemsTheir ability to provide automatic sprinkler protection in spaces where freezing is possibleExample locations may include: unheated warehouses and attics, outside exposed loading docks, and within commercial freezers

Disadvantages of Dry SystemsIncreased complexityHigher installation and maintenance costsLower design flexibilityIncreased response timeIncreased corrosion potentialWith the exception of unheated buildings, dry pipe systems are generally not recommended

Advantages of Deluge SystemsFaster response to fire occurrenceUsually more effective in controlling or extinguishing a fire conditionSingle action is required for water releaseUsed where large amounts of water is of minimal concern

Disadvantages ofDeluge SystemsRequires fire detectors for the actuation of the systemPotential water collection in the area of system operation

Advantages of Preaction SystemsDual action is required for water releaseUsed in water sensitive environmentsExample locations may include: archival vaults, fine art and storage rooms, rare book libraries and computer centers

Disadvantages ofPreaction SystemsHigher installation and maintenance costsModification difficultiesPotential decreased reliability

Standpipes / Hose Supply

System ComponentsListed - FM / UL / ULC / other recognized testing organizationsProperly designedProperly installedAdequately supported / bracedProtected from cold / vandalism / other damageRegularly testedMaintained

Automatic Sprinkler

Automatic SprinklersSprinkler Storage Cabinet

ValvesIdentification Signs

Fire Department ConnectionDRY PIPEVALVERISERMAINDRAINCONTROLVALVEAUTOMATIC BALL DRIPFIRE DEPT.HOSECONNECTIONCHECKVALVE

Fire Department ConnectionALARMCHECKVALVERISERMAINDRAINCONTROLVALVECHECKVALVEAUTOMATIC BALL DRIPFIRE DEPT.HOSECONNECTION

Fire Department Connection (FDC)

Problem?

SupervisionWaterflowWater level / temperature (tank)Water pressureAir pressure (dry pipe system / pressure tankValve tamperFire pump statusValve room temperatureOther

Water Overflow (Standby)SYSTEMPRESSURESUPPLYPRESSUREPRESSURE SWITCHLOCALELECTRICALARMWATERMOTOR GONGPILOTVALVERETARDCHAMBERCLAPPERCLOSED

Water Overflow, OperatingSYSTEMPRESSURESUPPLYPRESSUREPRESSURE SWITCHLOCALELECTRICALARMWATERMOTOR GONGRETARDCHAMBERCLAPPEROPEN

Water Motor Gong

Waterflow

Valve Tamper

Big Problems!

Questions one must ask? Sprinkler SystemIs the water supply adequate?Was the system properly installed, flushed and tested?Is the system and all components protected from cold, vandalism, or other damage?Does the owner thoroughly understand the system and know how it works?Is the system being properly tested and maintained?

Questions one must ask? ComponentsAre the sprinklers of the proper type, temperature classification, and obstructed?Are all sprinkler control valves accessible / open / locked / supervised?Is the sprinkler piping being used to support shelving / racks / storage / etc.?Is the fire department connection visible / accessible / in working order?Are the alarms tested / working / monitored?

Questions one must ask? OccupancyIs the sprinkler system designed for the present occupancy?Is the entire occupancy sprinklered?Is there unanticipated high piled stack / rack storage / aerosols / flammable liquids / other hazards?Is the building protected from exposure fires?Are the vertical / horizontal / openings protected?Are there unsprinklered combustible spaces?

Final ThoughtsSimply installing a sprinkler system will not guarantee adequate fire protection.

The system must be properly designed, installed, tested, and maintained to be effective.

QUESTIONS???