1407 pacific highway, warrawee€¦ · alternative solution report – 1407 pacific highway,...

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FIRESAFETYENGINEERING|ESSENTIALSERVICESMAINTENANCEMANAGEMENT|BUILDINGSERVICESDESIGN

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1407PACIFICHIGHWAY,WARRAWEEFIREENGINEERINGREPORTDEVELOPEDINACCORDANCEWITHTHEPERFORMANCEREQUIREMENTOFTHEBCA

• PROTECTIONOFOPENINGS• EXTENDEDTRAVELDISTANCES• REDUCTIONINFIRERESISTANCELEVELS• FIREHYDRANTPUMPROOM

DATE:15JUNE2017REPORTNO:0379-REVAFINALPREPAREDFOR:BAINIDESIGNPREPAREDBY:J2CONSULTINGENGINEERS|FIRESAFETYENGINEERING

J2CONSULTINGENGINEERS|FIRESAFETYENGINEERINGALTERNATIVESOLUTIONREPORT–1407PacificHighway,Warrawee

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CONTENTS

EXECUTIVESUMMARY&RECOMMENDATIONS........................................................................................4REQUIREMENTSOFALTERNATIVESOLUTION..........................................................................................4

1.0INTRODUCTION............................................................................................................................................61.1BasisoftheReport...................................................................................................................................................61.2PurposeoftheReport.............................................................................................................................................61.3LimitationsoftheReport.......................................................................................................................................71.4AssumptionsoftheReport....................................................................................................................................7

2.0FIREENGINEERINGBRIEF.........................................................................................................................82.1RelevantStakeholders............................................................................................................................................82.2BuildingandOccupantCharacteristics.............................................................................................................82.3Hazards,PreventativeandProtectiveMeasuresAvailable.......................................................................92.4DirectlyrelevantIFEGSub-Systems................................................................................................................11

3.0ALTERNATIVESOLUTION1–PROTECTIONOFOPENINGS..........................................................123.1Deemed-to-SatisfyProvisions...........................................................................................................................123.2DetailsofBCADTSDeviation.............................................................................................................................123.3RelevantPerformanceRequirement..............................................................................................................133.4AssessmentMethodology...................................................................................................................................133.5AcceptanceCriteria...............................................................................................................................................143.6QualitativeandQuantitativeAssessment.....................................................................................................153.7AssessmentagainstrelevantPerformanceRequirement.......................................................................163.9AssessmentConclusion.......................................................................................................................................17

4.0ALTERNATIVESOLUTION2–EXTENDEDTRAVELDISTANCES..................................................184.1Deemed-to-SatisfyDeviation.............................................................................................................................184.2DetailsofAlternativeSolution..........................................................................................................................184.3RelevantPerformanceRequirements............................................................................................................184.4AssessmentMethodology...................................................................................................................................194.5AcceptanceCriteria...............................................................................................................................................194.6QualitativeAssessment.......................................................................................................................................194.7AssessmentagainstrelevantPerformanceRequirement.......................................................................214.8AssessmentConclusion.......................................................................................................................................22

5.0ALTERNATIVESOLUTION3–REDUCTIONINFIRERESISTANCELEVELS................................235.1Deemed-to-SatisfyNon-compliance................................................................................................................235.2DetailsofBCADTSDeviation.............................................................................................................................236.3RelevantPerformanceRequirement..............................................................................................................235.4AssessmentMethodology...................................................................................................................................245.5AcceptanceCriteria...............................................................................................................................................245.6QuantitativeAssessment....................................................................................................................................255.7AssessmentagainstrelevantPerformanceRequirement.......................................................................255.8AssessmentConclusion.......................................................................................................................................26


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6.0ALTERNATIVESOLUTION4–FIREHYDRANTPUMPROOM........................................................276.1Deemed-to-SatisfyNon-compliance................................................................................................................276.2DetailsofBCADTSDeviation.............................................................................................................................276.3RelevantPerformanceRequirement..............................................................................................................286.4AssessmentMethodology...................................................................................................................................286.5AcceptanceCriteria...............................................................................................................................................286.6QualitativeAssessment.......................................................................................................................................296.7AssessmentagainstrelevantPerformanceRequirement.......................................................................306.8AssessmentConclusion.......................................................................................................................................30

7.0CONCLUSIONS..............................................................................................................................................317.1Conclusion................................................................................................................................................................317.2SpecificationoftheFinalTrialDesign............................................................................................................317.3MaintenanceRequirements...............................................................................................................................317.4RequirementsoftheAlternativesolution....................................................................................................31

8.0REFERENCES................................................................................................................................................32AppendixA–DataRelieduponintheFEB/RProcess..........................................................................32CommonAbbreviationsUsedinFireEngineering............................................................................................33ClientDesignandBuildingRegulatoryObjectives............................................................................................33MethodsofAnalysis.....................................................................................................................................................34RelevantIFEGSub-Systems.......................................................................................................................................34AcceptanceCriteriaandFactorsofSafetyfortheAnalysis............................................................................35ApproachesandMethodsofAnalysis....................................................................................................................37ConstructionandCommissioningRequirements..............................................................................................37

REVISION STATUS REPORT No. & REVISION DATE STATUS WRITTEN CHECKED 0359 REV A 17/01/17 DRAFT

JS JA

0359 REV A 15/06/17 FINAL

JS JA

COMMERCIAL IN CONFIDENCEThis document contains confidential material that is intended solely for J2 Engineering Pty. Ltd.. The project team and all regulatory authorities shall exercise precautionary measures to ensure that the information contained herein is not to be accessed by any third party. J2 Engineering Pty. Ltd will take no responsibility for the use of any information contained within this report by any third party.


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EXECUTIVESUMMARY&RECOMMENDATIONS

J2 Fire Engineers have been commissioned to carry out a fire safety engineering analysis and assessment of theproposedapartmentdevelopmentlocatedat1407PacificHighway,Warrawee.ThisreportprovidesaFireEngineeredAlternativeSolutiondevelopedtopermitthefollowingBCAnon-compliancesinthesubjectbuilding.AlternativeSolutions BCA DTS

ProvisionBCAPerformanceRequirement

AssessmentMethodology

Topermitwindowopeningstobelocatedmarginallylessthan3mfromthesideallotmentboundarywithoutrequiringprotectionaspertherequirementsofBCAC3.4.

C3.2,C3.4 CP2 QualitativeandquantitativeassessmentdemonstratingcompliancewiththeperformancerequirementsunderA0.3(a)(i)viaaperformancebasedapproachpermittedunderA.05(b)(ii).

Topermitextendedtraveldistancesofupto8.8mtoasingleexitservingtheapartmentsontheupperlevelsofthebuilding.

D1.4 DP4,EP2.2 QualitativeassessmentdemonstratingcompliancewiththeperformancerequirementsunderA0.3(a)(i)viaaperformancebasedapproachpermittedunderA.05(b)(ii).

Topermitareducedslabthickness(setdownof30mmtoallowfortilebeds)toachievetherequiredFRLof120/120/120or90/90/90dependingonthelocationofthesetdown.

B1.4,Spec.C1.1

CP1,CP2 QualitativeassessmentdemonstratingcompliancewiththeperformancerequirementsunderA0.3(a)(i)viaaperformancebasedapproachpermittedunderA.05(b)(ii).

Topermitthefirehydrantpumproomtobeaccessedviaastairwaynotcontainedinafireisolatedshaft.

E1.3 EP1.3 QualitativeassessmentdemonstratingcompliancewiththeperformancerequirementsunderA0.3(a)(i)viaaperformancebasedapproachpermittedunderA.05(b)(ii).

REQUIREMENTSOFALTERNATIVESOLUTION

Considering the relevant provisions of the BCA, the Alternative Solution, subject to the provision of the followingrequirements,isconsideredtomeetandcomplywiththePerformanceRequirementCP1,CP2,DP4,EP1.3andEP2.2:

AlternativeSolution11. Bedroomwindows1and2withinunitsG.1,1.1and2.1shallbeprovidedwithmetallicflyscreens,suitablefor

use in bushfire prone areas as per the requirements of AS3959, with maximum 2mm aperture size.Alternatively,thesewindowscanbefixedintheshutposition.

2. Bedroomwindows2and3,andthebathroomwindowwithinunitsG.4and1.4shallbeprovidedwithmetallicflyscreens,suitableforuseinbushfireproneareasaspertherequirementsofAS3959,withmaximum2mmaperturesize.Alternatively,thesewindowscanbefixedintheshutposition.

3. Bedroom windows 1 and 2, and the bathroom window within unit 2.4 shall be provided with metallic flyscreens, suitable for use in bushfire prone areas as per the requirements of AS3959, withmaximum 2mmaperturesize.Alternatively,thesewindowscanbefixedintheshutposition.

AlternativeSolution24. Theentrydoorwaystothestairwaysonlevels1and2shallbeconfiguredasself-closingsmokedoorswhich

shallbeprovidedwithmediumtemperaturesmokeseals.Theconstructionaroundthewallsandceilingshallberesistanttothepassageofsmokethroughsealingofanypenetrationsthroughthewall/ceilingconstructionofthestairwayonthesetwoupperlevels.

5. ThedoorwaysopeningintothelobbyfromtheSOUsandservicesroomonthegroundfloorshallbeprovidedwithmediumtemperaturesmokeseals.


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AlternativeSolution36. Theminimumslabthicknessatthepointofsetdownmustnotbelessthan150mmatanylocation.7. Theminimumconcretecoveronanysteelreinforcementbarsrunninghorizontallywithintheslabshallnotbe

lessthan30mm.

AlternativeSolution48. The fire hydrant pump room shall be provided with fire rated construction achieving a minimum FRL of

120/120/120withtheentrydoorwayachievingaminimumFRLof-/120/30.9. The wall bounding the carpark and the stairway/corridor leading to the fire isolated stairway shall be

provided with fire rated construction achieving a minimum FRL of 120/120/120 with the exit doorwayachievingaminimumFRLof-/120/30.

10. Thefirehydrantpumpshallbeautomaticallyoperatedfromapressureswitch,flowswitchorsimilar.Maintenance11. The recommendations of this reportmust form part of the fire safety certificate and the annual fire safety

statement for the building to ensure the recommendations of this report are compliedwith throughout thebuildingoperation.

TheAlternativeSolutionhasbeendevelopedusingcomparisonwiththeDeemed-to-SatisfyProvisionsandaqualitativeandquantitativeassessment, and is considered to complywithBCAPerformanceRequirementCP1,CP2,DP4,EP1.3andEP2.2.TheBCArecognisestheseAssessmentMethodasacceptablemethodsfordeterminingthattheAlternativeSolutionsatisfiesthePerformanceRequirementinaccordancewithBCAClausesA0.3(a)(i)andA0.5(b)(ii).


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1.0INTRODUCTION

J2 Fire Engineers have been commissioned to carry out a fire safety engineering analysis and assessment of theproposedapartmentdevelopmentlocatedat1407PacificHighway,Warrawee.ThisreportprovidesaFireEngineeredAlternativeSolutiondevelopedtopermitthefollowingBCAnon-compliancesinthesubjectbuilding.

• Topermitwindowopeningstobelocatedmarginallylessthan3mfromthesideallotmentboundarywithoutrequiringprotectionaspertherequirementsofBCAC3.4.

• Topermitextendedtraveldistancesofupto8.4mtoasingleexitservingtheapartmentsontheupperlevelsofthebuilding.

• Topermitareducedslabthickness(setdownof30mmtoallowfortilebeds)toachievetherequiredFRLof120/120/120or90/90/90dependingonthelocationofthesetdown.

• Topermitthefirehydrantpumproomtobeaccessedviaastairwaynotcontainedinafireisolatedshaft.Thisreportdemonstratesthatupontheadoptionofsuitablealternativesolutions,asdetailedintheExecutiveSummaryofthereport,therelevantPerformanceRequirementoftheBuildingCodeofAustralia(BCA)willbemet.

1.1BasisoftheReport

ThisAlternativeSolutionReportisbasedonadesktopassessmentofthefollowingdocumentation:

• BuildingCodeofAustralia2016,publishedbytheAustralianBuildingCodesBoard(ABCB)• InternationalFireEngineeringGuidelines2005,publishedbyAustralianBuildingCodesBoard(ABCB)• TheGuidetotheBCA2016,publishedbytheAustralianBuildingCodesBoard(ABCB)• ArchitecturaldetailspreparedbyBainiDesignasfollows:

DrawingNumber Revision01 B03 B04 B05 B06 B07 B08 B09 B10 B11 B

PreparationoftheAssessmentReportwillsatisfytherelevantPerformanceRequirementsoftheBCAthroughabsoluteassessmenttechniques.

Nootheraspectsorpartsofthebuildingapartfromthealternativesolutionsasoutlinedabovewillbeassessedandtheremainderof theproposeddevelopment isassumedtocomplywith therelevantDTSprovisionsor thePerformanceRequirementoftheBCA.

1.2PurposeoftheReport

Thisreporthasbeenpreparedtoaddressnon-compliancematterswith theDeemed-to-SatisfyProvisionsof theBCA(as tabled in the Executive Summary), and to provide an Alternative Solution developed in accordance with theprovisionsoftheBCA.Thepurposeof this report is todemonstrate that theproposeddevelopmentwill satisfyPerformanceRequirementsCP1,CP2,DP4,EP1.3andEP2.2asthedesignisatleastequivalenttotherelevantDeemed-to-SatisfyprovisionsoftheBCAand/orsatisfiesthePerformanceRequirementoftheBCA.


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This report is prepared for the purposes of submitting to the Certifying Authority (CA) for acceptance prior to theissuingofaConstructionCertificaterelevanttotheproposal.

1.3LimitationsoftheReport

Thisreportexcludesanyworksnotoutlinedabove,howeverspecificallyexcludesthefollowing:• Determining full compliancewith theBCA,other than thematters identified in theexecutive summaryof this

report;• AddressinganymattersthatareoutsidethescopeorlimitationsoftheBCA;• AmendmentstotheAlternativeSolutionBriefduetodesignchangesorincapacitytocomplywiththeTrial

Designs;• IssuingofanyPart4AcertificatespursuanttotheEnvironmentalPlanningandAssessmentAct1979.Thisreport

isnotaPart4AcompliancecertificateundertheEnvironmentalPlanning&AssessmentAct1979orRegulation2000;

• Considerationofanyfireservicesoperations(includinghydraulic,electricalorothersystems);• Consideration of any structural elements or geotechnical matters relating to the building, including any

structuralorotherassessmentoftheexistingfireresistancelevelsofthebuilding;• ThisreportdoesnotprovideconcessionsforanyAlternativeSolutionorexemptionsfromtherequirementsof

theBCA,otherthanthatidentifiedintheExecutiveSummaryofthisreport;• DeterminingcompliancewiththeDisabilityDiscriminationAct1992orPartD3oftheBCA;• Reportingonhazardousmaterials,OH&Smattersorsitecontamination;• Anyenergyefficiencyassessment;howeverifnecessary,proposalscanbeobtainedfromsuitablyqualifiedand

accreditedassessors.

1.4AssumptionsoftheReport

This report provides an Alternative Solution for the Deemed-to-Satisfy non-compliance identified in the ExecutiveSummary.Theremainderof thebuilding isassumedtocomplywiththeDeemed-to-SatisfyProvisionsof theBCAforthepurposeofthisreport.Thereportisprovidedonthebasisthat:• TheAlternativeSolutiononlyappliestopropertydetailedinsection2.2.• TheAlternativeSolutionisapplicabletothedesigndocumentationprovidedforassessmentandaslistedin• Section 1.1. Any future alteration, enlargement or addition will require re-assessment to determine the

applicationofthissolutiontothosechanges.• TheBuildingwill generally complywith theDeemed-to-Satisfy Provisions of theBCA, exceptwheremodified

specificallybythisreport.• It is assumed that the building will be subject to ongoing annual maintenance and the fire safety measures

requiredbythisreportandtheBCAwillbemaintainedtoastandardnotlessthantheirinstallationstandard.


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2.0FIREENGINEERINGBRIEF

The development of this report follows a consultative process with the Certifying Authority and the Developer’sRepresentative. In lieu of submitting a formal Fire Engineering Brief (FEB) for this project, the proposed fireengineeringassessmentwasdiscussedandagreeduponwiththecertifyingauthoritypriortocompletionofthisreport.FurtherdetailsofthedatarelieduponintheFEB/FERprocessaredetailedinAppendixA.

2.1RelevantStakeholders

Stakeholder/Role NameCertifyingAuthority CertifiedBuildingSpecialistsArchitect BainiDesign–RomanTalatoFireEngineer J2ConsultingEngineers–JamesSunjaya,James

Alexander

2.2BuildingandOccupantCharacteristics

GeneralBuildingCharacteristics

BuildingCharacteristic DescriptionOccupancy/UseBuildingClass/es:Typeofconstruction:StoreysContained;RiseinStoreys:EffectiveHeight:

ResidentialunitsandassociatedcarparkingonthebasementlevelsClass2,7aTypeA4411.7m

Location:Generaldescriptionofdevelopment:

1407PacificHighway,WarraweeThedevelopmentproposestoconstructthreestoreysofapartmentsatopabasementlevelcarparkassociatedwiththeapartmentbuildingabove.

OccupantCharacteristics

OccupantCharacteristic DescriptionTypeandnumber Occupants would generally be expected to be capable of caring for themselves

consistent with residential housing use. It is not anticipated that more than acombined50peoplewouldnormallyinhabitthetwelveresidences.

Occupantstate Building occupants could be both awake and asleep. Occupants may also beintoxicatedorsober.Occupantsonalllevelswouldbeexpectedtohaveareasonablelevelofmobilitytocomfortablynegotiatethestairsaccessonaday-to-daybasis.

Physical and mentalattributes

Themajority of occupants are considered to bemobile and ambulatory. Given thebuilding contains only fourteen units it is possible that a relationship will existbetween occupants, which would not normally be the case in a multi-storeyresidentialunitdevelopment.

Assistancerequired/available

Itwillbelikelythatassistancewillnotberequiredastheoccupantswillbefamiliarwiththelocationoftheexitsandthepathstotheexitsgiventhesimplelayout.TheassistanceavailablewillbeintheformoftheBuildingOccupantWarningSystem


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OccupantCharacteristic Descriptiontohelpoccupantsinanevacuation.Assistancemayalsobeprovidedfromotherablebodiedoccupants.

TrainingandRoles Occupantsareconsideredtohavelimitedtrainingorexperience.Hazards Kitchencookingareas.

Occupantssmokinginapartments.Electricalequipmentlocatedincorridorsprovidingelectricitytotheresidentialpartsaswellascommunicationscablingandequipment.Carrelatedfireinthebasementcarpark.

2.3Hazards,PreventativeandProtectiveMeasuresAvailable

Thefollowinghazardshavebeenidentifiedinthesoleoccupancyunits.Hazard Details/Precaution

GeneralLayoutandDesign Nohazardsidentifiedwithdesign.Activities Informationisnotavailabletosuggestthatactivitiesoutsidethose

normally undertaken in residential house will be carried out andhencethehazardisnotconsideredtobeincreased.

Cooking - NSWFB statistical dataindicates that these firesmake up 33%ofallreportedresidentialfires.(NSWFB2001/2002)

A smoke alarm or detection system would notify occupants torespond to cooking fire outbreaks if unattended. If the outbreakdevelops beyond that controllable occupants are required toevacuate.

Occupants smoking in Sole OccupancyUnits (SOU’s). NSWFB statistical dataindicates that fires in sleeping areasmakeup44%ofallreportedresidentialfires. These predominantly includesmokinginbedandcombustiblesplacedupon or near heaters. (NSWFB2001/2002)

A smoke alarm or detection system would notify occupants torespond to smoking related fire outbreaks if unattended. If theoutbreakdevelopsbeyondthatcontrollableoccupantsarerequiredtoevacuate.

Electrical equipment failure located inSOU’s,concealedspacesorcarpark.

SOUhabitablespaceA smoke alarm or detection system would notify occupants torespond to electrical fires. If the outbreak develops beyond thatcontrollableoccupantsarerequiredtoevacuate.ConcealedspacesTheroofvoidhazardislimitedtodownlightsandelectricalwiringasanignitionsourcewhichmakesupaverysmallpercentageofthenumber firestartsaccordingtheNSWFBstatisticaldata,hencetheroofvoidhazardisconsideredlow.CarparkandcommonareasElectrical failure is limited to Power outlets lighting and garagedoorfunctionsinthecarpark.Consideredaverylowlevelofhazard.

Multiple arson attack, malicious acts,andactsofterrorism.

The resulting impact of fires from these hazards has not beenaddressedinthisreportastheyarebeyondthescopeoftheBCA.

Thehazardsthatarepresentinthebuildinghavebeenremovedorreducedbysixsub-systemsofpreventativeandprotectivemeasures.Sub-System PresentinBuilding/Requirements


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Sub-System PresentinBuilding/Requirements

AFireinitiation,development

andcontrol

Fire loads or heat release rates are not proposed to be in excess of a normalresidentialunitoccupancyandhence firedevelopmentwillnotbeabnormallyfast.

BSmokedevelopment,spread

andcontrol

DTScompliantboundingconstructionbetweenSOU’swillpreventsmokespreadtoneighbouringunits.Theenclosingofthestairintoashaftassistsinimprovingtenabilityconditionsforbuildingoccupantsseekingegressintheeventofafire.

CFirespread,impactand

control

Fire separation between the SOU’s is compliant and provides an FRL of90/90/90 between units. Minor setdowns in the slab for the wet areas areprovidedwhich are addressedwithin an alternative solution containedwithinthisreport.

DFiredetection,warningand

suppression

An AS1670.1 smoke detection system or AS3786 smoke alarms will notifyoccupants toa fireoutbreak.Occupantsof theunit are likely tobenotifiedbyotheroccupantswithintheunitviaverbalcommunicationintheeventthattheyarelocatedremotefromthefire.

EOccupantevacuationand

control

Exitstoopenspaceareavailablefromeachunitwithoutpassingthroughorbyunprotectedopeningsoftheotherunit.

FFireservicesintervention

ThebuildingisservedbyfulltimefirebrigadepersonnelattheHornsbyNSWFBstationwhichislocated5.0kmfromthesite.Onthisbasis,itisconsideredthatfire services intervention is likely exceed or at least equivalent to mostresidentialareasinsuburbanSydneymetropolitanarea. Thedirectionstositefromthestationcanbeseeninthefigurebelow.

The nearest alternate fire station is the Gordon fire station which is located5.2kmfromthesite.

*InternationalFireEngineeringGuidelines2005(IFEG)Sub-systemA –FireInitiationandDevelopmentandControlSub-systemB –SmokeDevelopmentandSpreadandControlSub-systemC –FireSpreadandImpactandControlSub-systemD –FireDetection,WarningandSuppressionSub-systemE –OccupantEvacuationandControlSub-systemF –FireServicesIntervention


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2.4DirectlyrelevantIFEGSub-Systems

ThedirectlyrelevantIFEGsub-systems(SS)forthisanalysisare:IFEGSub-System Description SymbolSub-systemBSmokeDevelopment,SpreadandControl

• Smokesealsondoorsenteringstairway

Sub-systemCFireSpreadandImpactandControl

• Solidcoredoorsfittedwithself-closersfittedtoegressstairwayEnsuring minimum concrete cover is retained oversteelreinforcement.

Sub-systemFFireServicesIntervention

• Fire rating of doorset leading to corridor to protectfirefightersfromtheeffectsoffirewithinthecarparkareaofthebuilding.


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3.0ALTERNATIVESOLUTION1–PROTECTIONOFOPENINGS

AnalternativesolutionhasbeendevelopedtoaddresstheproposeddeviationfromtheDTSprovisionsofC3.2relatingtoallowingopeningswithinawallrequiredtoachieveafireresistanceleveltoremainunprotectedwithoutprovisionofwindowwettingfiresprinklers(asrequiredtosatisfyclauseC3.4).Thesolutionproposestoconsiderthesizeofthewindowopeningsandthesetbackofthewindowsfromtheboundarywhichappeartobemarginallylessthan3mfromtheadjacentsiteallotmentboundarywhenscaledofffloorplans.

3.1Deemed-to-SatisfyProvisions

ThefollowingDTSprovisionshavebeenidentifiedasbeingsubjecttothealternativesolution: C3.2ProtectionofopeningsinexternalwallsOpeningsinanexternalwallthatisrequiredtohaveanFRLmust—(a)ifthedistancebetweentheopeningandthefire-sourcefeaturetowhichitisexposedislessthan—

(i)3mfromasideorrearboundaryoftheallotment;or(ii)6mfromthefarboundaryofaroad,river,lakeorthelikeadjoiningtheallotment,ifnotlocatedinastoreyatorneargroundlevel;or(iii)6mfromanotherbuildingontheallotmentthatisnotClass10,beprotectedinaccordancewithC3.4andifwall-wettingsprinklersareused,theyarelocatedexternally;and

(b)ifrequiredtobeprotectedunder(a),notoccupymorethan1/3oftheareaoftheexternalwallofthestoreyinwhichitislocatedunlesstheyareinaClass9bbuildingusedasanopenspectatorstand.C3.4Acceptablemethodsofprotection(a)Whereprotectionisrequired,doorways,windowsandotheropeningsmustbeprotectedasfollows:

(i)Doorways—(A)internalorexternalwall-wettingsprinklersasappropriateusedwithdoorsthatareself-closingorautomaticclosing;or(B)–/60/30firedoorsthatareself-closingorautomaticclosing.

(ii)Windows—(A)internalorexternalwall-wettingsprinklersasappropriateusedwithwindowsthatareautomaticclosingorpermanentlyfixedintheclosedposition;or(B)–/60/–firewindowsthatareautomaticclosingorpermanentlyfixedintheclosedposition;or(C)–/60/–automaticclosingfireshutters.

(iii)Otheropenings—(A)excludingvoids—internalorexternalwall-wettingsprinklers,asappropriate;or(B)constructionhavinganFRLnotlessthan–/60/–.

(b)Firedoors,firewindowsandfireshuttersmustcomplywithSpecificationC3.4.

3.2DetailsofBCADTSDeviation

In accordance with C3.2(a)(i) and C3.4(a)(ii), window openings within an external wall required to achieve a fireresistancelevelmustbeprotectedwithwindowwettingsprinklersandbefixedclosed/automaticclosingorachieveafireratingthroughothermeans.Inthisinstance,itisproposedtopermitwindowslocatedatnonearerthan2.9mfromthesideallotmentboundarytoremainunprotectedwithintheclass2building.Theextentofexposedwindowscanbeseeninthefigurebelow.


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Figure1–ApartmentExposurestoEasternBoundaryShadedBlue(2.9mfromBoundary)

As is evident, there are a seriesofwindows locatedwithin3mof theboundarywhichwill be addressedwithin thisalternativesolution.

3.3RelevantPerformanceRequirement

PursuanttoA0.10(b)ofBCAthefollowingperformancerequirementhasbeenidentifiedasbeingdirectlyrelevanttotheDTSprovisionsidentifiedinSection3.1above:CP2(a)Abuildingmusthaveelementswhichwill,tothedegreenecessary,avoidthespreadoffire-

(i) toexits;and(ii) tosole-occupancyunitsandpubliccorridors;and(iii)betweenbuildings;and(iv)inabuilding

(b)Avoidanceofthespreadoffirereferredtoin(a)mustbeappropriateto-(i) thefunctionoruseofthebuilding;and(ii)thefireload;and(iii)thepotentialfireintensity;and(iv)thefirehazard;and(v) thenumberofstoreysinthebuilding;and(vi)itsproximitytootherproperty;and(vii)anyactivefiresafetysystemsinstalledinthebuilding;and(viii)thesizeofanyfirecompartment;and(ix)firebrigadeintervention;and(x) otherelementstheysupport;and(xi)theevacuationtime.

3.4AssessmentMethodology

In order to address the provisions of the BCA, a performance based approach will be adopted to demonstratecompliance of the Alternative Solution with the BCA. The proposed Alternative Solution will review the proposedsolutionusingquantitativeandqualitativemeasuresagainsttherequirementsofCP2.ThequantitativeassessmentwillassesscomplianceagainstBCAverificationmethodCV1.


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3.5AcceptanceCriteria

Itmustbeacceptedthattheopeningsaresuchthatfirespreadtoorfromtheboundaryoradjacentfiresourcefeatureisnotpromoted.IftheproposedalternativesolutioncandemonstratethattheopeningsarenotlikelytoresultinfirespreadviaopeningsintheadjacentbuildingthealternativesolutionwillbeconsideredtosatisfytherequirementsofCP2throughqualitativeandquantitativeabsoluteassessment.Quantitatively,itmustbeacceptedthattheproximityoftheunprotectedwindowsdoesnotpromoteincreasedriskoffire spread between each building and/or the property boundary. If the proposed alternative solution is capable ofdemonstrating that fire spread is unlikely to occur, it will be considered that the solution adequately satisfies theperformancerequirementsoftheBCA.FireSpreadtoBoundaryTheradiantheatfluxcriteriaforfirespreadtoboundariesissetoutintableCV1oftheBCAwhichstatesthat‘abuildingwill not cause heat flux in excess of those set out in column 2 of Table CV1 at locations within the boundaries of anadjoiningpropertysetoutincolumn1ofTableCV1whereanotherbuildingmaybeconstructed’.Column1 Column2Location HeatFlux(kW/m2)OnBoundary 801mfromboundary 403mfromboundary 206mfromboundary 10FireSpreadfromBoundaryFurthertothis,CV1statesthatwhenabuildingis‘locatedatthedistancesfromtheallotmentboundarysetoutincolumn1ofTableCV1,abuildingiscapableofwithstandingtheheatfluxsetoutincolumn2ofTableCV1withoutignition’.Itwillconservativelybeassumedthatallfireshaveachievedflashoverconditions.Inordertodeterminewhetherornotfirespreadhasoccurred,itisproposedtoutilisethefollowingradiantheatfluxcriteriawhichoutlinetherequiredlevelorradiantheatfluxtocausetheignitionofcellulosicmaterials(pilotedandnon-piloted)(Drysdale1998).

Figure2–RadiantHeatRequiredforPilotedandNon-PilotedIgnition

Ifitcanbedemonstratedthatignitionisnotcapableofoccurringviaaquantitativeanalysis,therequirementsofCP2willbeconsideredtobeachieved.


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3.6QualitativeandQuantitativeAssessment

FireSpreadtoBoundaryTableCV1oftheBCAoutlinesthemaximumradiantheatfluxespermittedtobereceivedattheboundary,1montheoppositesideoftheboundary,3montheoppositesideoftheboundaryand6montheoppositesideoftheboundaryfromawindow in the subject building. These radiant heat fluxes are 80kW/m2, 40kW/m2, 20kW/m2 and10kW/m2respectively.Calculationsundertakenindicatethatutilisingsimpleradiantheattransfercalculationsfromaflashoverfireburningat1,000˚C inthesubjectbuilding, thefollowing levelsofradiantheatarereceivedattheboundaryfromeachapartmentwindowlocatedat2.9mfromthesideallotmentboundary.Forthepurposesofcalculation,ithasbeenconservativelyassumedthatallwindowsfromeachapartmentaresimultaneouslyradiatingtowardstheboundary.Unit Window Width(m) Height(m) Setbackto

Centre(m)HeatFlux(kW/m2)atDistancesasListedAtboundary

1m fromboundary

3m fromboundary

6m fromboundary

UnitsG.1,1.1or2.1

Bed1Bed2

2.42.4

0.70.7

2.92.9

9.7


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Level Window TypeofOpening Width(m) Height(m) Setback(m) RadiantHeatReceived(kW/m2)

Unit2.4

Bed1Bed2Bath

DistanceUnknown.Assumedthatopeningis1mawayfromboundaryandhasdimensionsof12mlongby1.28minheight.

12m 1.28m 2.9fromboundaryand3.9fromradiator

22.3

Thetransmittedradiantheatfluxfromtheboundaryradiation(kW/m2)receivedatthewindowopeningswithinthreemetresoftheboundaryfromafireattheboundaryaredetailedinthetableabove.As per the above it can be seen that the radiant heat received at all of the assessedwindow openings exceed thatrequired for piloted ignition of the aluminium framedwindows (12.0kW/m2) as outlined in the acceptance criteriaabove.Theradiantheatfluxishowever,insufficienttoresultinnon-pilotedignition(occurringat28.0kW/m2)andonthisbasisitisproposedtoeitherfixthesewindowsintheshutpositionorprovideemberresistantmetallicflyscreensoverthewindowsthatwillpreventpilotedignitionfromoccurring.Onthebasisofthecalculationsundertakenabove,itisconsideredthattherelevantperformancerequirementCP2hasbeensatisfiedforopeningsfacingtheboundariesprovidingtheaffectedwindowsasscheduledaboveareprovidedwithemberresistantmetallic fly screens thatpreventember ingress.Thesescreensshallbeapproved foruse inbushfireproneareasaspertherequirementsofAS3959.

3.7AssessmentagainstrelevantPerformanceRequirement

The following table summarises the proposed qualitative assessment against the relevant performance requirementCP2.

CP2 (a)Abuildingmusthaveelementswhichwill,tothedegreenecessary,avoidthespreadoffire-

(i)toexits;and Notapplicabletothisalternativesolution.(ii) to sole-occupancy units and publiccorridors;and

Notapplicabletothisalternativesolution.

(iii)betweenbuildings;and The analysis demonstrates that a fire in the building will not result inradiantheatfluxesinexcessofthatoutlinedinverificationmethodsCV1and CV2 when fitted with metallic ember resistant screens withmaximum2mmaperturesize.

(iv)inabuilding Notapplicabletothisalternativesolution.(b)Avoidanceofthespreadoffirereferredtoin(a)mustbeappropriateto-

(i) the function or use of the building;and

Asoutlinedabove, thebuilding is considered tobea typical class2 lowriseapartmentbuildingwithoccupantsgenerallybeingfamiliarwiththelocationoftheexit(astheexitisformedbythefrontentrydoorway).

(ii)thefireload;and Asoutlinedabove,thefireloadisconsideredtobeequivalentto(aclass2building.

(iii)thepotentialfireintensity;and The fire intensity within the subject building is considered to beequivalenttothatofatypicalclass2building.

(iv)thefirehazard;and Thefirehazardscontainedwithinthebuildingarenodifferenttothatofatypicalclass2building.

(v)thenumberofstoreysinthebuilding; Thebuildingonlycontains4 storeyswhich is considered toensure that


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and rapid evacuation to open space can occur whilst ensuring that firefighting operations can be undertaken from outside that will mitigateagainstfirespreadtoneighbouringbuildings.

(vi)itsproximitytootherproperty;and The subject window openings are only marginally less than thatpermitted under the BCA (2.9m in lieu of 3.0m) and the provision ofmetallic fly screenswithmaximum 2mm aperture sizewill ensure thatpilotedignitioncannotoccur.

(vii) any active fire safety systemsinstalledinthebuilding;and

ThebuildingisprovidedwithsmokealarmsandfiredetectionandalarmsystemsaspertheDTSprovisionsoftheBCA.

(viii) the size of any fire compartment;and

The upper levels of the building are considered to be a single firecompartment with additional compartmentation provided around eachSOUtofurtherreducetheimpactoffirespreadwithinthebuilding.

(ix)firebrigadeintervention;and ThenearestfirebrigadeatHornsbyiswithinreasonableproximityofthebuildingandisafulltimestationthatwouldhaveeasyandquickaccesstosite.

(x)otherelementstheysupport;and Notapplicabletothisalternativesolution.(xi)theevacuationtime. The evacuation time is not considered to differ from that of a standard

class2dwelling.

3.9AssessmentConclusion

Whilst the DTS provisions of C3.2 and C3.4 require the provision of window wetting fire sprinkler protection toautomaticclosingorpermanentlyclosedwindowswithin3moftheboundaryfiresourcefeatureinabuildingofTypeAconstruction, in this instance, a qualitative and quantitative assessment has been undertakenwhich has establishedthatsprinklerprotectionisnotrequiredtobeprovidedastheseopeningsareunlikelytocausetheunduespreadoffire.On this basis, Performance Requirement CP2 is considered to be satisfied subject to the following additionalrequirements:

• Bedroomwindows1and2withinunitsG.1,1.1and2.1shallbeprovidedwithmetallicflyscreens,suitableforuse in bushfire prone areas as per the requirements of AS3959, with maximum 2mm aperture size.Alternatively,thesewindowscanbefixedintheshutposition.

• Bedroomwindows2and3,andthebathroomwindowwithinunitsG.4and1.4shallbeprovidedwithmetallicflyscreens,suitableforuseinbushfireproneareasaspertherequirementsofAS3959,withmaximum2mmaperturesize.Alternatively,thesewindowscanbefixedintheshutposition.

• Bedroom windows 1 and 2, and the bathroom window within unit 2.4 shall be provided with metallic flyscreens, suitable for use in bushfire prone areas as per the requirements of AS3959, withmaximum 2mmaperturesize.Alternatively,thesewindowscanbefixedintheshutposition.


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4.0ALTERNATIVESOLUTION2–EXTENDEDTRAVELDISTANCES

An Alternative Solution has been developed to address the proposed deviation from the DTS provisions to permitextendedtraveldistancesontheapartmentlevelsofthebuildingofupto8.8mtothesingleexitservingeachstoreyinlieuofthemaximum6mpermissibleundertheDTSprovisionsoftheBCA.

4.1Deemed-to-SatisfyDeviation

Pursuant to A.0.10(a) of BCA the following DTS provisions have been identified as being subject to the alternativesolution: D1.4Exittraveldistances(a) Class2and3buildings—

(i) Theentrancedoorwayofanysole-occupancyunitmustbenotmorethan—(A) 6mfromanexitorfromapointfromwhichtravelindifferentdirectionsto2exitsisavailable;

or(B) 20mfromasingleexitservingthestoreyatthelevelofegresstoaroadoropenspace;and

(ii) nopointonthefloorofaroomwhichisnotinasole-occupancyunitmustbemorethan20mfromanexitorfromapointatwhichtravelindifferentdirectionsto2exitsisavailable.

4.2DetailsofAlternativeSolution

InaccordancewithClauseD1.4(a)(i)(A)above,itisarequirementthateachSOUentrancedoorwaybenofurtherthan6m froman exit. In this case, thedistanceof travel to the top stair tread (considered to the exit), is at the furthest,located8.8mfromthefurthestSOUentrancedooronlevel1.Thiscanbeseeninthefigurebelow.

Figure2–ExtendedTravelDistanceonLevel1(Level2traveldistancesaresimilar)

4.3RelevantPerformanceRequirements

PursuanttoA0.10(b)ofBCAperformancerequirementsDP4andEP2.2havebeenidentifiedasbeingdirectlyrelevanttotheDTSprovisionsidentifiedinSection4.1above.DP4Exitsmustbeprovidedfromabuildingtoallowoccupantstoevacuatesafely,withtheirnumber,locationanddimensionsbeingappropriateto—(a) thetraveldistance;and


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(b) thenumber,mobilityandothercharacteristicsofoccupants;and(c) thefunctionoruseofthebuilding;and(d) theheightofthebuilding;and(e) whethertheexitisfromaboveorbelowgroundlevel.EP2.2(a) Intheeventofa fire inabuildingtheconditions inanyevacuationroutemustbemaintained fortheperiodof

timeoccupantstaketoevacuatethepartofthebuildingsothat—(i) thetemperaturewillnotendangerhumanlife;and(ii) thelevelofvisibilitywillenabletheevacuationroutetobedetermined;and(iii) theleveloftoxicitywillnotendangerhumanlife.

(b) Theperiodoftimeoccupantstaketoevacuatereferredtoin(a)mustbeappropriateto—(i) thenumber,mobilityandothercharacteristicsoftheoccupants;and(ii) thefunctionoruseofthebuilding;and(iii) thetraveldistanceandothercharacteristicsofthebuilding;and(iv) thefireload;and(v) thepotentialfireintensity;and(vi) thefirehazard;and(vii) anyactivefiresafetysystemsinstalledinthebuilding;and(viii) firebrigadeintervention.


Inordertoaddress theprovisionsof theBCA,aquantitativeandabsoluteperformancebasedsolution formulated inaccordance with A.0.3(a)(i) and A.0.5(b)(ii) has been adopted to demonstrate the compliance of the AlternativeSolutionwiththerelevantPerformanceRequirements.


It must be demonstrated that in the proposed trial design incorporating extended travel distances, the proposedarrangement categorically satisfies each element of the relevant performance requirements. If this is demonstrated,compliancewithDP4andEP2.2isconsideredtobeachieved.

4.6QualitativeAssessment

BCASectionD1.3outlineswhenfireisolatedstairwaysarerequiredtobeprovided.Inaclass2buildinghavingariseinstoreysof4withthebottommoststoreyonlyusedtohousevehicles,astairwayprovidingegressforthebuildingisnotrequiredtobefireisolated.Whilstitisthereforepermittedthatthisstairwayprovidesdirectconnectionbetweenthethreeapartmentlevelsinthebuilding, in this instance the central exit interconnects the threeupper storeysof thebuildingonlyandprovidesnointerconnectiontothebasement.Furthermore,thisexitisproposedtobeprovidedwithsmokeseparatingconstructionateachlevelwiththeentrancedoorwayconfiguredasaself-closingsolidcoredoorwaywhichwillbelocatedat5.4mfromthefurthestapartmentonlevel1and5.0mfromthefurthestapartmentonlevel2.Thiscanbeseeninthefigurebelow(level2shown).Itcanbeseenthatwhilst the traveldistance technicallyexceeds themaximumpermissible6mto thesingleexit, theproposed smoke resisting construction, coupledwith the fire rated bounding construction afforded through normalapartmentconstruction,willensurethatoccupantsreachaplaceofrelativesafetyearlier.Furthermore,thelikelihoodofsmokeingressintothestairwayfromlevels1or2(wheretheextendedtraveldistancesoccur),isreducedtherebyincreasingtheabilityforoccupantstoevacuatefromthebuilding.


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Figure3–ProposedTrialDesignIncorporatingSmokeResistingConstructiononLevel2(Level1similar)

Asameasureofconservatism,topreventsmokeloggingoftheentrycorridoronthegroundfloor,itisproposedthatmediumtemperaturesmokesealsbeprovidedontheentrydoorstoapartmentsonthegroundfloorofthebuildingascanbeseeninthefigurebelow.

Figure4–ProposedTrialDesignIncorporatingSmokeSealsonGroundFloorofBuilding

On this basis, the arrangement is considered to provide a high degree of life safety and is considered to achievecompliancewith relevant performance requirements DP4 and EP2.2 subject to the assessment against the relevantperformancerequirementscontainedbelow.


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ThefollowingisanassessmentoftherelevantPerformanceRequirementDP4andEP2.2.

DP4 Exits must be provided from a building to allow occupants to evacuate safely, with their number, location anddimensionsbeingsappropriateto-(a)thetraveldistance;and Whilstthetraveldistancetothetopofthestairwayisincreasedbeyond6m,

smokeresistingconstructionprovidedbetweenthefurthestapartmentandthe stairway,which encloses the entire staircase, provides a safe place foroccupantsbeforethe6mdistancehaselapsed.Onthisbasistheincreaseinlife safety to building occupants from the affected apartments in at leastsufficient to offset the additional 3.5s of egress time (assuming aconservativetravelspeedof0.8m/s).

(b) the number, mobility and othercharacteristicsofoccupants;and

Itisexpectedthatthemajorityofoccupantswouldberesidentswhowouldbe familiarwith the location of the exit. The building contains a relativelylownumberofbuildingoccupants and therefore evacuation is expected tooccurrapidly.

(c)thefunctionoruseofthebuilding;and

Theuse as a residential unit suggests occupantswill be very familiarwithexit options. Any guests are expected to be either accompanied, or willfollowexitsignageasappropriate.

(d)theheightofthebuilding;and

The distance of travel from the top floor to the point of discharge onlyinvolvestravellingdowntwolevelstoreachgroundfloorwheretheuseofanon-fireisolatedstairwayisconsideredtobeadequate.

(e) whether theexit is fromaboveorbelowgroundlevel.

Notrelevanttothisalternativesolution.

EP2.2 (a) Intheeventofafireinabuildingtheconditionsinanyevacuationroutemustbemaintainedfortheperiod

oftimeoccupantstaketoevacuatethepartofthebuildingsothat:

(i) the temperaturewillnotendangerhumanlife;and

Theadditionofsmokeseparationofthestairwayontheupperlevel,andtheprovisionofmedium temperature smoke seals to thedoorwayswithin thegroundfloorlobbywilldecreasetheabilityforfire/smoketoaffectbuildingoccupantsseekingevacuationfromthebuilding.

(ii)thelevelofvisibilitywillenabletheevacuation route to be determined;and(iii) the level of toxicity will notendangerhumanlife.(b)Theperiodoftimeoccupantstaketoevacuatereferredtoin(a)mustbeappropriateto(i) the number, mobility and othercharacteristicsoftheoccupants;and

Itisexpectedthatthemajorityofoccupantswouldberesidentswhowouldbe familiarwith the location of the exit. The building contains a relativelylownumberofbuildingoccupants and therefore evacuation is expected tooccurrapidly.

(ii)thefunctionoruseofthebuilding;and

Theuse as a residential unit suggests occupantswill be very familiarwithexit options. Any guests are expected to be either accompanied, or willfollowexitsignageasappropriate.

(iii) the travel distance and othercharacteristicsofthebuilding;and

Whilstthetraveldistancetothetopofthestairwayisincreasedbeyond6m,smokeresistingconstructionprovidedbetweenthefurthestapartmentandthe stairway,which encloses the entire staircase, provides a safe place for


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occupantsbeforethe6mdistancehaselapsed.Onthisbasistheincreaseinlife safety to building occupants from the affected apartments in at leastsufficient to offset the additional 3.5s of egress time (assuming aconservativetravelspeedof0.8m/s).

(iv)thefireload;and Thefireload,intensityandfirehazardisnotconsideredtodifferfromthatofatypicalapartmentbuilding.(v)thepotentialfireintensity;and

(vi)thefirehazard;and(vii) any active fire safety systemsinstalledinthebuilding;and

ThebuildingwillbeprovidedwithactivefiresafetysystemsaspertheDTSprovisionsof theBCAwhichwillconsistofsmokealarmsordetectors, firehydrantsandportablefireextinguishers.

(viii)firebrigadeintervention. The nearest fire brigade at Hornsby iswithin reasonable proximity of thebuildingandisafulltimestationthatwouldhaveeasyandquickaccesstosite.


Theaboveassessmenthasdemonstratedthattheproposedincreasesintraveldistanceareconsideredtobesufficienttobesufficientlyoffsetthroughtheproposedtrialdesignincorporatingadditionalsmokeresistingconstructionaroundthestairwayandwithinthegroundfloorlobbyofthebuilding.On this basis, it is considered that via demonstrating equivalence with the BCA DTS provisions, the relevantperformance requirements DP4 and EP2.2 are considered to be satisfied subject to the following additionalrequirements:

• Theentrydoorwaystothestairwaysonlevels1and2shallbeconfiguredasself-closingsmokedoorswhichshallbeprovidedwithmediumtemperaturesmokeseals.Theconstructionaroundthewallsandceilingshallberesistanttothepassageofsmokethroughsealingofanypenetrationsthroughthewall/ceilingconstructionofthestairwayonthesetwoupperlevels.

• ThedoorwaysopeningintothelobbyfromtheSOUsandservicesroomonthegroundfloorshallbeprovidedwithmediumtemperaturesmokeseals.


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5.0ALTERNATIVESOLUTION3–REDUCTIONINFIRERESISTANCELEVELS

Analternativesolutionhasbeendevelopedtopermitthebathroomstocontaina30mmsetdownintheconcreteslabforthetilebedandtoassesswhetherornotthiscompromisestheabilityoftheconcreteslabtoachievetherequiredfireresistancelevelof90/90/90or120/120/120dependingonthelocationofthesetdown.

5.1Deemed-to-SatisfyNon-compliance

ThefollowingDTSprovisionshavebeenidentifiedasbeingsubjecttothealternativesolution:B1.4(b) DeterminationofstructuralresistanceofmaterialsandformsofconstructionThestructuralresistanceofmaterialsandformsofconstructionmustbedeterminedinaccordancewiththefollowing,asappropriate:(b) Concrete: (i) Concreteconstruction(includingreinforcedandprestressedconcrete):AS3600. (ii) Autoclavedaeratedconcrete:AS5146.1. (iii) Post-installedandcast-infastenings:..Further to this, Spec. C1.1 requires an FRL of 120/120/120 be achieved on the ground floor of the buildingwhichseparates the basement level carpark from the residential areas, and that an FRL of 90/90/90 is provided betweenapartmentlevels(level1and2slab).


Inordertoprovidetherequiredwaterproofing,whilstensuringtherequiredfallstowardsfloorwastescanbeachievedinwetareas,atypicalconstructiondetailinvolvessettingdowntheslabandscreedingthefloorontoptoenabletiledfloorswithinwetareastobeinstalledatgrade.Thistypicaldetailcanbeseeninthefigurebelow.

Figure5–ProposedSlabSetDownArrangement

Asisevident,wheretheslabissetdown,adecreaseinconcretecoveroverthesteelreinforcementexistswhichwillreduce the required fire resistance of the slab. This alternative solutionproposes to calculate the required concretecoveronthesteelelementstodeterminewhetherornot theproposed30mmreduction inthe200mmconcreteslabwillcompromisetheabilityfortheslabtoachieveanFRLof120/120/120intheworstinstance.


PursuanttoA0.10(b)ofBCAperformancerequirementCP1andCP2havebeenidentifiedasbeingdirectlyrelevanttotheDTSprovisionsidentifiedabove.CP1andCP2statethat:


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CP1Abuildingmusthaveelementswhichwill,tothedegreenecessary,maintainstructuralstabilityduringafireappropriateto-(a) thefunctionoruseofthebuilding;and(b) thefireload;and(c) thepotentialfireintensity;and(d) thefirehazard;and(e) theheightofthebuilding;and(f) itsproximitytootherproperty;and(g) anyactivefiresafetysystemsinstalledinthebuilding;and(h) thesizeofanyfirecompartment;and(i) firebrigadeintervention;and(j) otherelementstheysupport;and(k) theevacuationtimeCP2(a)Abuildingmusthaveelementswhichwill,tothedegreenecessary,avoidthespreadoffire-

(i) toexits;and(ii) tosole-occupancyunitsandpubliccorridors;and(iii)betweenbuildings;and(iv)inabuilding

(b)Avoidanceofthespreadoffirereferredtoin(a)mustbeappropriateto-(i) thefunctionoruseofthebuilding;and(ii)thefireload;and(iii)thepotentialfireintensity;and(iv)thefirehazard;and(v) thenumberofstoreysinthebuilding;and(vi)itsproximitytootherproperty;and(vii)anyactivefiresafetysystemsinstalledinthebuilding;and(viii)thesizeofanyfirecompartment;and(ix)firebrigadeintervention;and(x) otherelementstheysupport;and(xi)theevacuationtime.


In order to address the provisions of the BCA, a performance based approach will be adopted to demonstratecompliance of the Alternative Solution with the BCA. The proposed Alternative Solution will review the proposedsolutionusingquantitativemeasuresagainsttherequirementsofCP1andCP2.Thequantitativeanalysiswillcalculatethe required level of concrete cover over the structural elements to determine whether or not the fire resistingperformance is insufficient to achieve the required FRLs. In the case that the required FRLs are incapable of beingachieved,itisproposedtoundertakefireseveritycalculationstodeterminewhatFRLswouldberequiredinordertoovercomeaflashoverfirewithinthebuilding.


Itmustbeacceptedthat therequiredconcretecoveroversteelreinforcementwithinthe200mmthickconcreteslab(wherereducedto170mmdueto30mmslabsetdown)isreadilyachievabletoeitherachievetheDTSFRLsasoutlinedintheBCAorreducedFRLswhichwillbesubjecttofireseveritycalculationsifrequired.

If this can be demonstrated, it will be considered that the solution adequately satisfies the relevant performancerequirementsCP1andCP2.


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5.6QuantitativeAssessment

Research undertaken by the Portland Cement Association (Bilow et. al 2008) provides a technical review of therequiredconcreteperformancewhenexposedtofire.Thereviewoutlinestheminimumthicknessesoffloorslabs,andtheminimum required concrete cover over steel reinforcement beams in order to achieve certain durations of fireresistingperformance.Thetablebelowdeterminesthatinordertoachieveafireratingof2hours,theminimumslabthicknessisbetween3.6and5inches(91.4to127mm)dependingonthetypeofaggregateused.Inthiscasetheslabthicknessis200mm,whichisproposedtobereducedinareasby30mmtoaminimumslabthicknessof170mm.Thegroundfloorslabtherefore isconsideredtobeofsufficient thickness toachievetherequired120/120/120(2hour)fireresistingperformance,andthelevel1and2slabsaresimilarlyconsideredtoachievetherequired90/90/90(1.5hour)FRL.

Figure6–MinimumSlabThicknesstoAchieveFireResistingPerformanceinCastinPlaceFloorandRoofSlabs(ininches)

Thepaperalsooutlines theminimumrequiredconcretecoveroversteel reinforcementbeamswithinconcreteslabswhichcanbeseeninthefigurebelow.Onceagain,dependingonthetypeofaggregateused,inordertoachieveafireresistanceof2hours,therequiredconcretecovermustbebetween0.75-1inches(19.1-25.4mm).Giventhethicknessoftheslabat170mmatthepointofsetdown,itisconsideredthatthiswouldbereadilyachievablebyprocuringandinstallingchairsofthecorrectdimensionatthispointintheslab.

Figure7–MinimumConcreteCoverforFloorandRoofSlabs(ininches)

On thisbasis it is considered that compliancewith theDTSprovisionsof theBCA is readilyachievablewhichwouldthereforesatisfyrelevantperformancerequirementsCP1andCP2.


ThefollowingtableprovidesananalysisoftheproposedarrangementagainsttherelevantPerformanceRequirementCP1andCP2todeterminewhetherornotcomplianceiscapableofbeingachieved.CP1A building must have elements which will, to the degree necessary, maintain structural stability during a fireappropriateto-(a)thefunctionoruseofthebuilding;and

Thebuildingisusedasanapartmentbuilding.

(b)thefireload;and Thefireload,intensityandfirehazardareconsistentwiththatofatypicalapartmentbuilding.(c)thepotentialfireintensity;and

(d)thefirehazard;and(e)theheightofthebuilding;and Theriseinstoreysis4whichisrelativelylowandfacilitateseaseofegress

foroccupantsandeaseofaccessforattendingfirefighters.


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CP1(f)itsproximitytootherproperty;and Notapplicabletothisalternativesolution.(g) any active fire safety systemsinstalledinthebuilding;and

ThebuildingwillbeprovidedwithactivefiresafetysystemsaspertheDTSprovisionsoftheBCAwhichwillconsistofsmokealarmsordetectors,firehydrantsandportablefireextinguishers.

(h) the size of any fire compartment;and

Theupperlevelsareconsideredtoformasingle‘firecompartment’butarefurther divided into smaller fire rated areas through the provision ofcomplyingboundingconstruction.

(i)firebrigadeintervention;and Thenearest firebrigadeatHornsby iswithinreasonableproximityof thebuildingandisafulltimestationthatwouldhaveeasyandquickaccesstosite.

(j)otherelementstheysupport;and The slab is load bearing and is considered to be able to provide therequiredperformanceundertheDTSprovisionsoftheBCA.

(k)theevacuationtime. Thetimetoevacuatethebuildingwhichhasarelativelylowriseinstoreysisnotconsideredtoexceed2hours.

CP2(a)Abuildingmusthaveelementswhichwill,tothedegreenecessary,avoidthespreadoffire-(i)toexits;and Notapplicabletothisalternativesolution.(ii)tosoleoccupancyunitsandpubliccorridors;and


(iii)betweenbuildings;and Notapplicabletothisalternativesolution.(iv)inabuilding. Aspertheinformationprovided,theproposedfireresistancelevelsarenot

proposedtobereducedbeyondthatoftheDTSprovisionsoftheBCAwhichshouldbereadilyachievableattheslabsetdown.

(b)Avoidanceofthespreadoffirereferredtoin(a)mustbeappropriateto-(i) the function and use of thebuilding;and

RefertoCP1above.

(ii)thefireload;and RefertoCP1above.(iii)thepotentialfireintensity;and RefertoCP1above.(iv)thefirehazard;and RefertoCP1above.(v) the number of storeys in thebuilding;and

Theriseinstoreysis4whichisrelativelylowandfacilitateseaseofegressforoccupantsandeaseofaccessforattendingfirefighters.

(vi) its proximity to other property;and

RefertoCP1above.

(vii) any active fire safety systemsinstalledinthebuilding;and

RefertoCP1above.

(viii)thesizeofthefirecompartment;and

RefertoCP1above.

(ix)firebrigadeintervention;and RefertoCP1above.(x)otherelementstheysupport;and RefertoCP1above.(xi)theevacuationtime. RefertoCP1above.


Theaboveanalysisdemonstratesthatdespitehavingasetdownof30mminareasoftheslab,therequiredFRLsarestillcapableofbeingachievedproviding:

• Theminimumslabthicknessatthepointofsetdownmustnotbelessthan150mmatanylocation.• Theminimumconcretecoveronanysteel reinforcementbars runninghorizontallywithin theslabshall

notbelessthan30mm.


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Providing the above is adhered with, compliance with the relevant performance requirements CP1 and CP2 isconsideredtobeachieved.6.0ALTERNATIVESOLUTION4–FIREHYDRANTPUMPROOM

AnalternativesolutionhasbeendevelopedtoaddresstheproposeddeviationfromtheDTSprovisions topermitthefirehydrantpumproomtobeaccessedfromastairwaywhichisnotfireisolated.

6.1Deemed-to-SatisfyNon-compliance

BCAClauseE1.3hasbeenidentifiedasbeingsubjecttothealternativesolution.E1.3Firehydrants(a) Afirehydrantsystemmustbeprovidedtoserveabuilding—

(i) havingatotalfloorareagreaterthan500m2;and(ii) whereafirebrigadeisavailabletoattendabuildingfire.

(b) Thefirehydrantsystem—(i) mustbeinstalledinaccordancewithAS2419.1,exceptaClass8electricitynetworksubstationneednot

complywithclause4.2ofAS2419.1if—(A) itcannotbeconnectedtotownmainsupply;and(B) onehourwaterstorageisprovidedforfirefighting;and

(ii) where internal fire hydrants are provided, theymust serve only the storey on which they are locatedexceptthatasole-occupancyunit—(A) inaClass2 or3buildingorClass4part of abuildingmaybe servedbya single firehydrant

locatedatthelevelofegressfromthatsole-occupancyunit;or(B) ofnotmorethan2storeysinaClass5,6,7,8or9buildingmaybeservedbyasinglefirehydrant

locatedatthelevelofegressfromthatsoleoccupancyunitprovidedthefirehydrantcanprovidecoveragetothewholeofthesole-occupancyunit.

Furthertothis,AS2419.1states:6.4.2InternalpumproomsPumproomslocatedwithinabuildingshallhave–

a) Adooropeningtoaroadoropenspace,oradooropeningtofire-isolatedpassageorstairwhichleadstoaroadoropenspace;and

b) ExceptwherethebuildingissprinklerprotectedinaccordancewithAS2118.1,enclosingwallswithanFRLnotlessthanthatprescribedbytheBCAforafirewallfortheparticularbuildingclassificationservedbythefirehydrantsystem.


Intheproposedarrangement,theaccesstothefirehydrantpumproomisneitherachievedfromadooropeningdirecttoroadoropenspace,norfromafire-isolatedpassage.Ascanbeseeninthefigurebelow,thefirehydrantpumproomis provided with a doorway which in turn opens into an airlock which then involves having to travel belowapproximately3mofundercoverspacebeforeleadingtoopenspace.Asthepumproomdoesnotopendirecttoopenspace,thiscorridorisrequiredtobefireisolated.Theproposalistoallowthiscorridorspacetocontinuetoopendirecttoopenspaceinlieuoffireisolatingtheentirecorridor.


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Figure8–FireHydrantPumpRoomAccess


PursuanttoA0.10(b)ofBCAperformancerequirementEP1.3hasbeenidentifiedasbeingdirectlyrelevanttotheDTSprovisionsidentifiedabove.EP1.3Afirehydrantsystemmustbeprovidedtothedegreenecessarytofacilitatetheneedsofthefirebrigadeappropriateto—(a)fire-fightingoperations;and(b)thefloorareaofthebuilding;and(c)thefirehazard.


InordertoaddresstheprovisionsoftheBCA,anabsoluteassessmenthasbeenadoptedwhichassessestheproposeddeviation against the provisions of relevant performance requirementEP1.3 to determinewhether categorically therequirementsaresatisfiedthroughqualitativeassessmenttechniques.AnassessmentofeachofthedeviationsabovewillbeundertakenagainsteachaspectofEP1.3.


TheproposedarrangementwillbeconsideredtoachievecompliancewiththerelevantperformancerequirementEP1.3iftheabsoluteandqualitativeanalysisdemonstratesthateachelementoftherelevantperformancerequirementsarecategoricallysatisfied.Furthermore,thesolutionwillneedtobedemonstratedtosuittheoperationalrequirementsofthefirebrigade.


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6.6QualitativeAssessment

AS2419.1providesguidanceforexternalpumproomsasfollows:6.4.3ExternalpumproomsPumproomsandenclosures,locatedexternaltoandwithin6mofanynon-sprinklerprotectedbuildingtheyareprotecting,shallhaveenclosingwallswithanFRLnotlessthanthatprescribedbytheBCAforafirewallfortheparticularbuildingclassificationservedbythefirehydrantsystem.Asisevident,thereareoptionstolocatethefirehydrantpumproomeitherinternaltothebuilding,orexternaltothebuilding.Theintentbehindclauses6.4.2and6.4.3appearstobe:

• Toensurethatfirefighterscaneasilyaccessthepumproomwithoutbeingsubjecttothedangerouseffectsoffire

• Toensurethatfirefighters,whenlocatedwithinthepumproom,aresafefromthedangerouseffectsoffire.Inthiscase,thefullheightmasonryconstructionsurroundingthefirehydrantpumproomwillenablethepumproomto be easily fire rated through the provision of a fire door to the fire hydrant pump room. Furthermore the wallboundingthestairwayandthebasementactsasaretainingwall(toretainthefillbeneaththestair)andwillalsobeconstructedasamasonrywall.Onthisbasisthemethodofconstructionbetweenthestairway,corridorandthecarparkappearstoberelativelyfirerated.Byprovidingaself-closingfiredoorbetweenthecarparkandthestairwaycorridor,itisconsideredthatfullfireseparationcanbeachievedinthislocation.Whilst this still does not technically complywith AS2419.1 clause 6.4.2 as the entire corridor does not form a fireisolated tunnel, thearrangement is similar to thatpermitted in clause6.4.3 forexternalpumproomswhere the firepumproomandaccesstoitisfireseparatedfromthebuildingitisprotecting.Furthertothis thereasontheproposed internal firepumproomdoesnotopendirect toopenspace(aspermitted inclause6.4.2) is that there is a small sectionof overhanging soffit (approx. 3m in length).By fire ratingbetween thecarparkandthisare,theriskofafireoccurringinthisareaisextremelylowandthearrangementcanbeconsideredtobesimilartoapumproomwhichopensdirecttoopenspace.OnthisbasisitisconsideredthattheintentofAS2419.1isachievedthroughthetrialdesignwhichcanbeseeninthefigurebelow.

Figure9–ProposedTrialDesignIncorporatingFireRatedConstruction


30

Onthebasisoftheaboveit isconsideredthattherelevantperformancerequirementEP1.3issatisfiedsubjecttothefollowingassessmentagainsttheEP1.3.


The following table summarises the proposed qualitative assessment against the relevant performance requirementEP1.3.

EP1.3 Afirehydrantsystemmustbeprovidedtothedegreenecessarytofacilitatetheneedsofthefirebrigadeappropriateto—

(a) fire-fightingoperations;and

Theproposedfireratingofthewallboundingthecarparkandthestairwaycorridorwillensurethatfirefightersareprovidedwithsafeaccesstothefirehydrantpumproomtoshutofftheautomaticallyoperatedfirehydrantpumpsetsifrequiredtofacilitatefirefightingoperations.

(b) thefloorareaofthebuilding;and


(c)thefirehazard Thefirehazardinthestairwaycorridorislargelynon-existent.


An alternative solutionhas beendeveloped to permit the access to the fire hydrant pump room to not be via a fireisolated corridor or direct from open space. This has been demonstrated to comply with relevant performancerequirementEP1.3,subjecttocompliancewiththetrialdesignrequirementslistedbelow:

• Thefirehydrantpumproomshallbeprovidedwith fireratedconstructionachievingaminimumFRLof120/120/120withtheentrydoorwayachievingaminimumFRLof-/120/30.

• Thewall bounding the carpark and the stairway/corridor leading to the fire isolated stairway shall beprovidedwith fire rated constructionachievingaminimumFRLof120/120/120with theexitdoorwayachievingaminimumFRLof-/120/30.

• Thefirehydrantpumpshallbeautomaticallyoperatedfromapressureswitch,flowswitchorsimilar.


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7.0CONCLUSIONS

7.1Conclusion

TheAlternative Solutionhasbeendevelopedusingaquantitative assessment andaqualitative comparisonwith theDeemed-to-Satisfy Provisions and quantitative assessment and is considered to comply with BCA PerformanceRequirementsCP1,CP2,DP4,EP1.3andEP2.2.TheBCArecognisestheseAssessmentMethodasacceptablemethodsfordeterminingthat theAlternativeSolutionsatisfies thePerformanceRequirement inaccordancewithBCAClausesA0.3(a)(i)andA0.5(b)(ii).Accordingly,basedontheabove,itisconsideredthatthedirectlyrelatedPerformanceCP1,CP2,DP4,EP1.3andEP2.2havebeenmet,providedtheAlternativeSolutionrequirementslistedaboveareimplemented.

7.2SpecificationoftheFinalTrialDesign

Considering the relevant provisions of the BCA and the above assessment, the Alternative Solution, subject to theprovisionoftheTrialDesignrequirements,isconsideredtomeetandcomplywiththePerformanceRequirementCP1,CP2, DP4, EP1.3 and EP2.2. The Trial Design requirements detailed in each solution and in the Executive SummarybecometheAlternativeSolutions.

7.3MaintenanceRequirements

Therecommendationsofthisreportmustformpartofthefiresafetycertificateandtheannualfiresafetystatementforthebuildingtoensuretherecommendationsofthisreportarecompliedwiththroughoutthebuildingoperation.

7.4RequirementsoftheAlternativesolution

The discussions undertaken have demonstrated compliance with the relevant performance requirements via theproposeddesignandinstallationofoffsetmeasures.TheoffsetmeasuresrequiredaspartofthisAlternativeSolutionarelistedintheExecutiveSummaryandmustbefullyimplementedinorderforcompliancetobeachieved.

JamesSunjaya JamesAlexanderDirector DirectorMFSE,B.Eng.(Elec.),B.Med.Sci.BPBAccreditedFireEngineerGradeC10TASRegisteredBuildingPractitioner(FireSafety,BuildingServices)VICRegisteredBuildingPractitioner(FireSafety)RegisteredProfessionalEngineerQueenslandNPERandCPEng(FireSafety,BuildingServices)

B.App.Sci(Bldg),GradDip(DispRes),ME(Firesafety),GradDip(BldgSurv)AIBSNationallyAccreditedLevel1BuildingSurveyorBPBGradeA1AccreditedCertifierandPCAFireSafetyEngineer


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8.0REFERENCES

• AustralianBuildingCodesBoard,“FireSafetyEngineeringGuidelines”,Edition2001,November2001,

Australia.

• AustralianBuildingCodesBoard,“TheBuildingCodeofAustralia”,Edition2011,May2011,Australia.

• AustralianBuildingCodesBoard,“TheGuidetotheBuildingCodeofAustralia”,Edition2007,May2007,Australia.

• IFEG(2005).InternationalFireEngineeringGuidelines2005,ABCB.

• NSWFB(2001/2002)."NSWFireBrigadeAnnualStatisticalReportTenYearReview."

• Bilow,D.N.,Kamara,M.E.,(2008)“FireandConcreteStructures”,ASCE

AppendixA–DataRelieduponintheFEB/RProcess


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CommonAbbreviationsUsedinFireEngineeringAbbreviation/Term Meaning

AFAC FireandEmergencyServiceAuthoritiesCouncil

AS AlternativeSolution

ASB AlternativeSolutionBrief - identical toFEB.ASBwillnotbeusedother than torelate thistermtotheFireEngineeringBrief.

ASR AlternativeSolutionReport-identicaltoFEB.ASRwillnotbeusedotherthantorelatethistermtotheFireEngineeringReport.BCA BuildingCodeofAustralia.

CFD ComputationalFluidDynamics–Usedtodescribethefiremodellingforabuilding

Comparative

Amethodologyusedforafireengineeringanalysisthatusesacomparisonwiththedeemedto satisfy provisions of the BCA. Thismethodology shows that the alternative solution isequivalent to the DTS provisions of the BCA and is often referred to as the equivalenceapproach.

DTS Deemed-To-Satisfy-RepresentingthedeemedtosatisfyprovisionssetoutintheBCA.

Equivalence The equivalence approach is a fire engineering approach using a comparison to the DTSprovisionsoftheBCA.FEB FireEngineeringBrief-identicaltoASB.FEBisusedthroughoutthereport.

FER FireEngineeringReport-identicaltoASR.FERisusedthroughoutthereport.

FDS Fire Dynamics Simulator – The software program used to perform fire modelling onbuildingsFRL FireResistanceLevel

FRNSW FireandRescueNewSouthWales

IFEG InternationalFireEngineeringGuidelines

NFPA NationalFireProtectionAuthority

SFPA SocietyofFireProtectionEngineers.

ClientDesignandBuildingRegulatoryObjectivesTheclientdesignobjectivesaretoaddresstheissuesofdeemed-to-satisfynon-compliancewiththeproductionofanalternativesolutionthatmeetstherelatedPerformanceRequirement.OneofthepurposesofthisFireEngineeringReportistoprovidethestakeholderswithadocumentforconsiderationandtoaddfurtherinputwithregardstothespecificobjectives.ThestructureoftheBCAisdepictedinthefollowingfigureandisahierarchaldocumentwithobjectives,functionalstatementsandPerformanceRequirement.

TheprimaryobjectivesoftheBCAaretoprotectthelifesafetyofoccupantsbyallowingthemtoexitthebuildingwithoutbeingexposedtohazardousoruntenableconditions,theprotectionofadjacentbuildingsfromcollapseorfirespreadandprotectionofthelifesafetyoffirefightersbygivingreasonabletimefortheemergencypersonneltoperformtheirduties.


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ThePerformanceRequirementaretheonlysectionoftheBCAtowhichadesignmustcomply,withobjectivesandfunctionalstatementsgivenasguidancetoexplaintheintentofthePerformanceRequirement.SatisfyingthePerformanceRequirementcanbeachievedthroughoneofthreeways:

a) ComplyingwithDeemed-To-Satisfy(DTS)provisionsoftheBCAb) FormulatinganAlternativeSolutionwhichcomplieswiththePerformanceRequirementc) Combinationofa)andb)

ForthisparticularprojectthemeansofcompliancetotheBCAwillbeshownbycomplyingtoa/b/cabove.BCAclauseA0.9providesthefollowingassessmentmethodstodeterminethatabuildingsolutioncomplieswiththeBCAPerformanceRequirement:

a) Evidence to support that the use of amaterial, form of construction or designmeets a Performance Requirement or aDeemed-to-SatisfyProvision

b) VerificationMethodssuchas—i) TheverificationmethodsintheBCA;orii) Such other verification methods as the appropriate authority accepts for determining compliance with the

PerformanceRequirementc) ComparisonwiththeDeemed-to-SatisfyProvisionsd) ExpertJudgement

TheassessmentmethodsthatwillbeadoptedforthisprojectareinaccordancewithA0.9aboveandthespecificmethodsaredetailedinthealternativesolutionsections.

MethodsofAnalysisThemethodsofanalysisusedinthedevelopmentofalternativesolutionsaredetailedinBCAClauseA0.9,andincludeA0.9(b)(i) VerificationMethods,suchastheVerificationmethodsintheBCAA0.9(b)(ii) VerificationMethods,otherthanthoseintheBCAthattheappropriateauthorityacceptsforcompliancewiththe

PerformanceRequirementA0.9(c) Comparisontothedeemed-to-satisfyprovisionsoftheBCAA0.9(d) ExpertjudgementInordertosatisfyBCAClauseA0.5-MeetingthePerformanceRequirement(b) formulatinganAlternativeSolutionwhich-

(i) complieswiththePerformanceRequirement;or(ii) isshowntobeatleastequivalenttotheDeemed-to-SatisfyProvisions;

Thespecificassessmentmethodsusedfortheanalysisaredetailedinalternativesolutionsectionforeachissue.

RelevantIFEGSub-SystemsTherelevantIFEGsub-systems(SS)forthisanalysisare:

IFEGSub-System Description Symbol

Sub-systemA

FireInitiationandDevelopmentandControl

Limitationofignitionsources

Limitationofnatureandquantityoffuel

Arrangementandconfigurationoffuel

Separationofignitionsourcesandfuel

Management of combustibles including housekeepingmeasures

Electricalsafetyequipment

Regularplantmaintenance

Adherencetoproceduresfor'hotwork'(e.g.welding)


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IFEGSub-System Description Symbol

Sub-systemB

SmokeDevelopmentandSpreadandControl

Smokebarriers

Naturalsmokeventing

Mechanicalsmokemanagement

Sub-systemC

FireSpreadandImpactandControl

Separationoffuel

Separationofbuildings

Fireresistivebarriers

Fireresistivestructuralelements

Fireresistiveair-handlingducts

Fireresistivedampers

Exposureprotection

Sub-systemD

FireDetection,WarningandSuppression

Automaticandmanualdetectionequipment

Automaticandmanualwarningequipment

Surveillanceequipment

Automaticsuppressionequipment

Manualsuppressionequipment

Sub-systemE

OccupantEvacuationandControl

Evacuationplans

Occupanttraining

Emergencycommunications

Egresssignage

Egressroutes(includingfireisolatedelements)

Sub-systemF

FireServicesIntervention

Type of fire services available (full-time/permanent orvolunteer).

Characteristicsoffireservicescapabilityandresources

Fireserviceaccesstothesiteandtothebuilding

Watersuppliesandinfrastructure

AcceptanceCriteriaandFactorsofSafetyfortheAnalysisQualitativeAssessmentsTheacceptancecriteriaforqualitativeassessmentsaretheequivalencetoadeemedtosatisfysolution(preferred)orthecollectiveagreementofthestakeholders.TheIFEGallowsbothqualitativeandquantitativeapproachesandstatesthat-"themethodschosenwillbeappropriatetotheapproachused".TheIFEGstates-"Intheminorityofcases,qualitativeanalysismaybeagreedduringtheFEBprocesstobesufficientfortheconsiderationofasinglenon-complianceissue.Thebasis(logic)onwhichthisapproachisusedshouldbedocumentedwithappropriatereferences.A“Delphi”approachmayalsobeappropriateincertaincircumstances,whereagroupofsuitablyqualifiedexpertprofessionalsreachconsensusagreementregardingthesuitabilityofaparticularsolution."TheIFEGfurtherstates-"Bothcomparativeandabsoluteapproachesmaybeadoptedintheanalysisstrategy.Themethodschosenwillbeappropriatetotheapproachused.Comparativeapproach:


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Typically,thefiresafetyprovidedbyoneelement,orasub-system,orthecompletefiresafetysystem,iscomparedtotheleveloffiresafetythatwouldbeachievedinanidenticalbuildinginwhichthatelement,sub-systemorsystemisdesignedincompliancewiththedeemed-to-satisfyorprescriptiveprovisionsidentifiedinSection1.2.8.Iftheanalysisiscarriedoutonsuchacomparativebasis,itwillinvolvethesameassumptions,models,calculationsandinputdatafortheproposedtrialdesignandthedeemed-to-satisfyorprescriptivedesign.Acomparativeapproachaimstodeterminewhetherthealternativesolutionisequivalentto(orbetterthan)thedeemed-to-satisfyorprescriptivedesign.Thecomparativeapproachisoftenreferredtoasan“equivalence”approach."QuantitativeAssessmentsThefollowingacceptancecriteriaareproposedfortheassessmentofthealternativesolutionscompliancewiththePerformanceRequirementoftheBCA.Theacceptancecriteriawillbetodemonstratethatfiresafetyisnotadverselyaffectedandthattheoccupantsmaysafelyevacuatethebuildingand/orthefirewillnotspreadtoadjacentpropertyand/orwillallowfirefighterstosafelyperformtheirduties.HeatRadiation-Thelimitingconditionforradiationisassumedtobeintherange1.57to6.3kW/m2.Thetolerancetimeforradiationatthislevelis6minutes.

FireBrigadeIntervention:Inconsideringtheroleofthefirebrigadeinattackingafire,itisimportanttoestimatethetimeatwhichthebrigadewillbeeffectiveinlimitingthespreadofthefireandreducingtheheatoutputofthefireintheenclosureoffireorigin.Howeverthisresponsetimeisvariableandisafunctionofthetimeatwhichthealarmisreceivedatthefirestation,thetraveltimetothebuilding,thesetting-uptimeoncethefirebrigadehasarrivedandthetimetoimpactthefire.Whilethefirebrigadewillbeavailabletoassistevacuationthroughsearchandrescueofoccupants,thisactionisnotrelieduponforoccupantevacuation.Thefiresafetyassessmentisthereforeconservativeinthisregard.Theconditionsthatdefinethetenabilitycriteriaforfirebrigadepersonnelwillbeconsiderediftheoccupantscannotbeshowntohavesufficientavailableegresstimepriortoonsetofuntenableconditions.Incertaininstancesthefirebrigadeinterventiontimeswillberequiredtobedeterminedandtenabilityforthefirefightersassessedi.e.deletionofsprinklersfromacarpark.ThetimeforthefirebrigadetoarriveandcommencefirefightingoperationswillbedeterminedusingtheFireBrigadeInterventionModelorliteraturedataonthefirebrigaderesponsetimetofires.SummaryofTenabilityFailureCriteria:

Condition CriteriaConvectiveheat Temperature>60oCwhensmokelayerisbelowtenabilityheight.Radiantheatexposure

2.5kW/m2 at head height or smoke layer temperature exceeds 200oC when abovetenabilityheightof2.1m.

Visibility 10mwhen smoke layer is below tenability height of 2.1m for large rooms or 5m forsmallrooms.

Toxicity OD>0.1m–1(10dB/m)whensmoke layer isbelowtenabilityheightof2.1m,butnotaccessedifvisiblyacceptable.

Thefollowingtableisanoverviewofthetenability’sasacceptedbytheFireandEmergencyServiceAuthoritiesCouncil(AFAC)1.

RoutineConditionHazardousCondition

ExtremeCondition

CriticalCondition

MaximumTime,min 25 10 1 10

1 Weng Poh ‘Tenability in building fires: Limits and design criteria’. Fire Australia, 2010, No. 3,. pp 24-26

T<1.57kW/m2to6.3kW/m2


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ApproachesandMethodsofAnalysisApproachFireengineeringdesigncaninvolvetheuseofanumberofapproachesincluding:

• ComparativeorAbsolute• QualitativeorQuantitative• DeterministicorProbabilistic

TheIFEGgivesdescriptionsofeachtypeofapproach,whereitcanbenotedthatadeterministicorprobabilisticapproachcanonlybeappliedtoaquantitativeanalysis.Thedifferencesbetweenacomparativeandabsoluteapproachandtypicalexamplesofacceptancecriteriaaredepictedinthefollowingtable(reproducedfromUKFireEngineeringGuidelinesPD7974-0).Comparativevs.AbsoluteApproach

FireSafetyObjectives

AnalysisMethod Deterministic Probabilistic

Comparative TimeavailableforescapeisatleastequaltothatinanequivalentcodecompliantbuildingLevelofriskoflifeequivalenttoacodecompliantbuilding

Absolute ThetimeavailableforescapeexceedsthetimetountenableconditionsExpectednumberofcasualtiesperyear

Adefinitionofeachtypeofapproachisoutlinedinthefollowingtable,whichhasbeenadoptedfromtheIFEG.Thetypeofapproachadoptedwilldependonthetypeofcomplianceissueinquestionandsubsequentmethodsofanalysiswillbeprepared.AnalysisApproaches

Approach Definition

Comparative A comparative approachaims todeterminewhether the alternative solution is equivalent to (orbetterthan)thedeemed-to-satisfyorprescriptivedesign.Thecomparativeapproach isoftenreferredtoasan“equivalence”approach.

Absolute In an absolute approach, results of the analysis are matched directly against the PerformanceRequirementoftheBCA,usingagreedacceptancecriteria.

Qualitative AqualitativeanalysismaybeagreedduringtheFEBprocesstobesufficientfortheconsiderationofminorstand-alonecompliance issues.Thebasis (logic)onwhich thisapproach isusedshouldbedocumentedwithappropriatereferences.

Quantitative Thecomplexityofthecomplianceissueswilloftenrequireaquantitativeapproach.ThisentailstheuseofoneormoreofthemanyanalysismethodsavailableThequantitativemethodswilloftenbesupportedbyadditionalqualitativearguments.

Deterministic Deterministicanalysesarebasedonphysicalrelationshipsderivedfromscientifictheoriesandempiricalresults.Characteristically,foragivensetofinitialboundaryconditions,adeterministicmethodologywillalwaysproducethesameoutcome.Theydonot,however,indicatetheprobabilityofthatoutcomebeingrealized.

Probabilistic Probabilistic approaches use a variety of risk based methodologies. These methods generally assignreliabilities to the performance of the various fire protection measures and assign frequencies ofoccurrenceofevents.Theymayanalyseandcombineseveraldifferentscenariosaspartofacompletefireengineeringevaluationofabuildingdesign.Thisuseofmultiplescenariosandtheircombinationthroughprobabilistictechniquesisthekeyfeatureofsomeofthemethods.

ConstructionandCommissioningRequirementsThefiresafetymeasuresshallbedesigned,installedandcommissionedinaccordancewiththerelevantAustralianStandards.

• Themanagementof thebuildingmustbeawareof theAlternativeSolutioncontainedwithin thebuilding,aswellas therequiredmeasuresformaintenance.

• The BuildingManagement System,must incorporatemaintenancemeasures to ensure satisfactorymaintenance, testingandinspectionofallfiresafetymeasures.

Allfiresafetymeasuresaretobecommissionedandtestedpriortooccupationofthebuilding.Thefireservicescontractormustprovidecertificationoftheinstallationandcommissioningofthefireservicesrequiredbythisreport,includingbutnotlimitedto:


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• FireHydrantsSystems• Smokedetection• Firedoorsandsmokeseals• Exitsignage&emergencylighting• Appropriatedoorhardwareanddoorswing

Thefiresafetymeasureswithinthebuildingmustbemaintainedtoensurecorrectoperationatalltimesthatthebuildingisoccupied.Allfirefightingequipmentshouldbetaggedwhentested/inspectedandlogbookskeptup-to-dateforallsmokedetection,warningsystemsandsprinklersystems(whereinstalled).AnannualfiresafetycertificatemustbesubmittedtothelocalconsentauthorityandtheNSWFireBrigadeeachyearindicatingsatisfactoryperformanceofthefiresafetymeasurescontainedwithinthebuilding.Theannualfiresafetystatementshouldbedisplayedinaprominentplacewithinthebuilding(i.e.themainentryfoyer).Thecorrectoperationandmaintenanceofthebuildingsfiresafetymeasuresiscriticalinaffordinganadequateleveloffiresafety.OtherissuesidentifiedintheFEB/Rthatwillneedtobeincorporatedintothemanagementinuseofthefacilityinclude:

• Nosmokingpolicyistobeimplementedinallpublicareas.• Commissioning and integrated function testing of all fire safety and protection systems including interfaces to ensure

properfunction.• AllessentialservicesaretobemaintainedandtestedinaccordancewithBCAandAustralianStandardAS1851.• Ensureexitsandpathsoftraveltoexitsremainunobstructed(inparticularstairways).• Avoidstorageofmaterialsinunoccupiedareas.• Limitstorageofflammable/combustiblematerialstodesignatedandapprovedareas.• Preventchockingopenfire/smokedoors.• Preventstorageofmaterialsthatcouldhinderaccesstofirefightingequipment.

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