SECTION 7: page Contents Background research: why Voice Alarm is the future for Fire Alarm systems 2 The difference between Public Address (PA) and Voice Alarm (VA) 3 BS 5839 Part 8: 998 Fire detection and alarm systems for buildings 3.1 Section 1 General 3.2 Section 2 Design considerations 3.3 Section 3 Workmanship, installation & commissioning 3.4 Section 4 User responsibilities 3.5 Annexes 4 Current solutions 4.1 Voice sounders 4.2 Central Rack systems 4.3 Distributed amplifiers 5 Guideline for future designs Background research: why Voice Alarm is the future for Fire Alarm systems “It has often been observed that occupants – in the initial moments of a fire, upon smelling smoke or hearing the fire alarm – do not react; they deny there is danger or they ignore the situation. This seems especially true in public buildings where occupants do not want to be seen to overreact to a false alarm or to a situation that is already under control. Such avoidance behaviour in a dangerous situation often results in a delayed start to evacuating a building or taking protective action”. This statement by Dr Guylène Proulx 1 was further illustrated by research carried out by Brian Piggott of the Fire Research Centre and published by David Canter of Surrey University 2 which showed that in the event of a fire: l 13% of people reacted to bells l 45% of people reacted to text l 75% of people reacted to voice It was also made clear that in the event of an alarm people generally exit by the entrance they first used and need to be directed to the nearest escape route. A Voice Alarm system can be used to give people clear information about when to evacuate and what route to take and hence alleviate some of the problems highlighted above. 2 The difference between Public Address (PA) and Voice Alarm (VA) Many people believe they can simply use their PA system to provide a voice message in the event of an emergency like a fire. Unfortunately PA systems, whilst very good for providing music and messages, cannot be relied upon to work in an emergency. This is where the British Standard BS 5839 Part 8: 1998 on Voice Alarm comes into use, as it clearly defines the requirements of a true VA system. A true VA system is a HIGHLY SECURE PUBLIC ADDRESS system which has the following features; l All internal and external circuits are monitored for faults l A minimum battery back up of 24 hours standby and 30 minutes alarm (subject to suitable standby emergency generator provision) l A monitored secure link to a fire alarm panel l A number of pre-recorded emergency messages l Incorporates an emergency ‘firemans’ microphone – for complex buildings or buildings with phased evacuation The use of speech sounders is not considered as a true VA system and the recommendations detailed within ‘annexe E’ of the standard should be consulted. References 1: Guylène Proulx, Ph.D,’Misconceptions about human behaviour in fire emergencies’ published in Canadian Consulting Engineer, March 1997, pp36, 38. 2: David Cantor, ‘Studies of Human Behaviour in Fire: Emprical results and their implications for education and design.’ Published by BRE, July 1985 Designing Voice Solutions Section 7.: Designing Voice Solutions The following is a guide for designers on VA / PA systems and their use in conjunction with advanced fire detection systems, incorporating the requirements of BS 5839 Part 8: 1998. It will highlight some of the main considerations in system design paying particular attention to intelligibility, which is the key differentiator between poorly and well designed voice solutions.
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SECTION 7: page �
Contents
� Background research: why Voice Alarm is the future for Fire Alarm systems
2 The difference between Public Address (PA) and Voice Alarm (VA)
3 BS 5839 Part 8: �998 Fire detection and alarm systems for buildings
� Background research: why Voice Alarm is the future for Fire Alarm systems
“It has often been observed thatoccupants – in the initial moments ofa fire, upon smelling smoke or hearingthe fire alarm – do not react; theydenythere isdangerorthey ignorethesituation. This seems especially true inpublic buildings where occupants donot want to be seen to overreact toa false alarm or to a situation that isalready under control. Such avoidancebehaviourinadangeroussituationoftenresultsinadelayedstarttoevacuatingabuildingortakingprotectiveaction”.Thisstatement by Dr Guylène Proulx1 wasfurther illustrated by research carriedoutbyBrianPiggottoftheFireResearchCentre and published by David CanterofSurreyUniversity2whichshowedthatintheeventofafire:l 13%ofpeoplereactedtobells
l 45%ofpeoplereactedtotext
l 75% of people reacted to voice
Itwasalsomadeclearthatintheeventofanalarmpeoplegenerallyexitbytheentrancetheyfirstusedandneedtobedirectedtothenearestescaperoute.AVoiceAlarmsystemcanbeusedtogivepeopleclearinformationaboutwhentoevacuate and what route to take andhence alleviate some of the problemshighlightedabove.
2 The difference between Public Address (PA) and Voice Alarm (VA)
Many people believe they can simplyuse theirPAsystem toprovideavoicemessage intheeventofanemergencylikeafire.
Unfortunately PA systems, whilst verygoodforprovidingmusicandmessages,cannot be relied upon to work in anemergency. This is where the BritishStandard BS 5839 Part 8: 1998 onVoiceAlarmcomesintouse,asitclearlydefines the requirements of a true VAsystem.A trueVAsystem isaHIGHLYSECURE PUBLIC ADDRESS systemwhichhasthefollowingfeatures;
l Allinternalandexternalcircuitsaremonitoredforfaults
l Aminimumbatterybackupof24hoursstandbyand30minutesalarm(subjecttosuitablestandbyemergencygeneratorprovision)
l Amonitoredsecurelinktoafirealarmpanel
l Anumberofpre-recordedemergencymessages
l Incorporatesanemergency‘firemans’microphone–forcomplexbuildingsorbuildingswithphasedevacuation
The use of speech sounders is notconsidered as a true VA system andthe recommendations detailed within‘annexe E’ of the standard should beconsulted.
References
1: Guylène Proulx, Ph.D,’Misconceptions about human behaviour in fire emergencies’ published in Canadian Consulting Engineer, March 1997, pp36, 38.
2: David Cantor, ‘Studies of Human Behaviour in Fire: Emprical results and their implications for education and design.’ Published by BRE, July 1985
We also suggest reference is made toBS5839Part1:2002.
The standard is split into various sections, the following looks at the key points for designers in each section.
3.1 Section 1 General
The key part of this section for anew design is the need to exchangeinformation with interested parties, asit is likely that the informationgatheredhere will form the basis of the design.Anunderstandingneedstobegainedofwhatmessagesaretobeplayedintheeventofa fireorotheremergenciesaswellaswhatthesystemmaybeaskedtodoinaddition,suchasmusicand/orpaging.
Thissectionalsoprovidesafullplanningschedule as a check list which is wellworth following, especially for anyonewho is embarking on a design for thefirsttime.
Thedesigners’checklistisasfollows:
l Surveyofthesiteand/oradetailedexaminationofsitedrawingsincludinganacousticassessment
l Assessment of usage of the buildingincluding;
l Periodsofnonoccupation
l Areaswithhighnoiselevels
l Personnel including those hard ofhearing
l Actionsthattakeplaceintheeventofafire
l Liaisonwithallmanufacturerstoensurecompatibilitybetweenthefireandvoicealarmsystems
l Asystemspecificationandrequirementsforestimationpurposes
l Tenderingandquotation
l Considerationofproposals
l Considerationofservicingrequirements
l Agreementonproposalsandconfirmationof‘Fireplan’
l Agreementonthe‘controls’iemicrophonesetc
l Detailedsystemdesign
l Ordering
l Agreementonfinalspecificationincludinganyvariations
l Production,pre-deliveryacceptancecertificateanddelivery
l Installationandtestingphase
l Commissioning
l Systemdocumentationandusertraining
l Acceptancebyclient
l Handoverofsystem
l Serviceagreement
It goes on to suggest that for large sitesconsiderationsbeincludedfor:
l Understandingthestagesofa‘criticalpath’chart
l Sitingandaccommodationofthecontrolequipment
l Onsiteworknotconflictingwithotherservices
l Temporaryphysicalprotectiontoavoiddeteriorationofequipmentduetodamp,dustetc
l EnsuringfinalcommissioningoftheVAsystemiscarriedoutwhenallpartiescanwitnesstheresultsundervariousoccupationlevels–itmaybenecessarytoconsiderpartialoccupationandsoaktestingtoensureallpartiesareultimatelysatisfiedwiththefinalresult
Design Stage 3
Section 7.�: Designing Voice Solutions
SECTION 7: page 3
3.2 Section 2 Design consideration
Like all the Fire application standardsthis section is by far the largest andadditional training on this section isadvised for anyone heavily involved inVAdesign.
Some of the KEY issues the designershouldconsiderare:
The Distribution of the speaker circuits
Monitoring of loudspeaker circuits isrequired. In certain circumstances it isrecommendedthat theyare interleavedtoensurethevoicemessageisdeliveredthroughout a zone, irrespective ofwhether one of the two circuits havefailed.
The Choice and siting of the speakers
Loudspeakers should be positioned toachievethecorrectsoundpressure(dB)level and good intelligibility, with anSTI (speech transmission index) of 0.5consideredtobeacceptable.
Speaker selection should not be asimple matter of aesthetics and it isoftenadvisabletocarryoutanacousticsurveytoestablishthebestsolutionforaparticularapplication.
The Link between the Fire and VA control panels
The link between the fire control paneland theVoicealarmcontrolunit needsto be secure, that is monitored foropen and short circuits, latching in itsoperation and wired in recognised fireresistant cables to avoid failure, as theVA may be the only means of warningpeoplethereisafire.
In complex buildings where activationoftheEvacuateandAlertsignalcanbemanuallyoverriddenitshouldbeclearlyindicated on the control panel whichareaisreceivingwhichmessage.
l InsuchcasestheoperationofthesoundersshouldnotaffecttheintelligibilityoftheVAsystem
l Thesoundertoneshouldbethesameasthe‘attentiondrawingtone’usedbytheVAsystem
l Theproceduresforoperatingsuchsystemsshouldbesimpletoavoidconfusionintheeventofanemergency
l Ifitisnecessarytosilencethealarmsounderstoenableavoicemessagetobebroadcastthenrestartingofthesoundersshouldbeautomatic.Thereshouldnotbeasilentperiodexceeding10secondsbetweenbroadcastandsounders
The installation requirements followclosely the recommendations withinBS 5839 Part 1: 2002. However thecrucial issuehere is thecommissioningstageespeciallycheckingof thesoundpressurelevels(dB’s)andintelligibility.
Specialist equipment may be requiredto check the audibility and intelligibility.However the standard suggests thatto check the sound pressure level, astandard sound level meter set to ‘A’weightingand ‘slow response’willgiveanapproximatereading,aslongasthespeech is slow in delivery with virtuallyno gaps. A more reliable method ofmeasuringwouldbetouseareferencesignal such as ‘speech shaped’ pinknoise.
Intelligibility is a little more difficult andwhilst a minimum STI of 0.5 is quoteditmaybedifficultornear impossible toachieve under all circumstances. Thestandard suggests that a subjectiveassessment of intelligibility may besufficient as long as all interestedparties agree. In the case of dispute itis recommended that an appropriatemethodofmeasurementdetailedwithinBSEN60268Part16mayberequired.
Design Stage 3
Section 7.�: Designing Voice Solutions
SECTION 7: page 4
3.4 Section 4 User responsibilities
The major issue for the user, besidesensuring theequipment isnotshowingany faultsand ishealthyatall times, isensuring theoperators fullyunderstandhow to use the system. This may bean ongoing requirement as personnelchange and complex procedures forphased evacuation, which requiremanualintervention,maybeinplace.
3.5 Annexes
TheannexesAtoEprovideadesignerwith some useful data in respect ofloudspeaker capabilities, typical noiselevels in different buildings, a batterystandby calculator, a model certificateandaguidelineorrecommendationsfortheuseofvoicesounders
All these methods are acceptable,dependent on the type and size ofbuildingwheretheyarebeinginstalled.
4.� Stand alone voice sounders or voice enhanced sounders
Although these devices cannot beconsideredatrueVAtheydooffervoicemessages,witheachdevicecontaininga ‘memory’ chip that has a numberof pre-recorded standard messages,operated directly from the fire alarmcontrolpanel.
Itisimportantthatthecontrolpaneldoeshavea‘synchronisation’capabilitysoallthe independent recorded messagesaredeliveredatthesametime.
This is particularly important when youhave two or more alarm zones wheredifferent messages are required, i.e.an Evacuate and Alert message, assynchronisationandintelligibilitymaybeaffected.
Furthermore additional cables may berequired to switch from one messagetoanother.
It is therefore, suggested that thesedevices are generally used for thesmallerpropertieswherethereisa‘oneout–allout’evacuationrequiredandnomessagingorbackgroundmusicfacilityisneeded.
Design Stage 3 and 4
Section 7.�: Designing Voice Solutions
SECTION 7: page 5
4.2 Central Rack systems
CentralRacksystemsconsistofarackorracksofamplifiersthatcontrolallthespeakercircuits,whichareradiallywiredas shown. This rack may also contain facilities for zoneselection, music input, emergency and general pagingannouncements.
Thebenefitsofthisapproachare:
l Anoptionalsingle,monitoredserialdatalinktothecontrolpanel–requiringnoconnectiontothelooporusageofvaluableaddressspaces
l Compatibilitywithnon-serialsupportedcontrolpanelsisaffordedbyanoptionalconnectiontolooppoweredmonitoredsounderorcontrolmodules
l Centrallylocated,rackmountedsystem–alldistributioncomponentsarelocatedinonesecureplace,providingeaseofmaintenance
l Flexibilityofinterfacingwith3rdpartysystemsviainterfacemodules
A Master ACU allows additional SlaveACUs or microphone units to besupported.ThisSlaveactsasasecondVAcontrolpanelandmimicsthecontrolsof the Master. No keypad or LCD forprogrammingisprovidedattheSlave.
The Master ACU can be supplied aseitherablankversionorcompletewithauserinterfaceandintegralemergencymicrophone. A Master ACU is alwaysrequiredwhenmorethanoneDAUistobeusedonthesamesystem.
TheACUenablespagingannouncementstobemadetothedistributedsystems.An interface isprovided toallow inputsfrom the Vigilon control panel(s) tocontrol Digital Voice Announcements(DVAs)fromthedistributedsystems.
Control Network Operation
Thecontrolnetworkactsasatransparenttransmission medium for the controlprotocoltobetransmittedfromtheACUtotheDAUs.
Thenetworkisconfiguredasaloopandistoleranttoopenorshortcircuitcablefaults betweennodesof the loop. Thisis achieved by the network normallyoperating in a preferred transmissiondirection, should a fault be detected,the originating node shall effectivelytransmit in both directions around thering.ReceivingDAUsareabletodetectthenewdatadirection.
Audio Distribution
BasebandAudiowill requireonecopperpair per channel. Three audio channelsare supported as a minimum to enablesimultaneous ‘Alert’, ‘Evacuate’ andemergency microphone audio to bebroadcast. In non-emergency conditionsthe audio channels may be used forbackground music and routine pagingfunctions. The audio loops are fault-tolerant.
As well as distributing the audio, itis required that a master microphone,Press-to-talk, signal is also conveyedover the audio link. This is to fulfil theBS 5839 Part 8 requirement that an“All-Call Fireman’s Microphone”operation is supported even if controlprocessorsfail.
ItispossibleformultipleACUmicrophonestocontendforasingleaudiochannelforemergencymicrophoneannouncements.A simple global priority is implementedbetween microphones for grantingaccess.
SECTION 7: page 7
Data Highway1 x 2 x 1mm2
230V acsupply
LocalInputs
Audio Highway3 x 2 x 1mm2
EVAC
ALERT
MIC
DATA
EVAC
ALERT
MIC
DATA
230V acsupply
230V acsupply
Music Source
MasterACU
Slave ACU
DAU
4x A/BSpeakerzones
A
B
A/B
A/B
A/B
A
B
A/B
A/B
A/B
Vigilon Fire Panel
Fire Detecton Loop
PagingMicrophones
EVAC
ALERT
MIC
DATA
230V acsupply
LocalInputs
4x A/BSpeakerzones
DAU
S-Quad MCP
Additional Emergency Microphone
Vigilon Voice System Architecture
Section 7.2: Gent by Honeywell Voice Solutions
by Honeywell
SECTION 7: page 8
TheMasterACUtakestheform
of a wall-mounted box fulfilling
the primary function of a Voice
AlarmControlPanel.
TheACUfeaturesakeypadand
LCD display for configuration
and fault reporting, and can
be supplied either blank, with
no further control functions,
or with an integral emergency
microphone and a number of
configurable frontpanelbuttons
for zone selection, and 8
push button selectors for DVA
broadcasts.
TheACUisabletointerfacewith
the Vigilon fire alarm system to
facilitatecentralisedcontrol. It is
possibletoconnectaPCviaan
RS232interfaceforprogramming
of the ACU itself, or any of the
attachedsatelliteDAUs.
TheACUwillautomaticallydisplay
thestatusofallconnectedDAUs
bymeansof the standardFault
LED/Sounderarrangementand
withacyclingdisplayona local
(2x40)LCD.
IftheblankversionoftheMaster
ACU is supplied, in order to
provide the same functionality,
an additional Desk Console
or wall mounted Emergency
Microphone can be provided in
placeoftheon-boardKeypad.
ORDER CODES
ACU with 20 way keyboard and network VA-1312
ACU Slave with 20 way keyboard VA-1313
20 Way Desk Console and Emergency Microphone VA-1315
l DigitalMessages–Two66secondemergencymessagesandtwo50secondAuxiliaryMessagesareprovided.
l AudioMonitorInput–Aconnectionisprovidedforanaudiomonitorbusfromtheamplifiersystem.Thisallowsforaudiomonitoringofselectedamplifieroutputsunderthecontrolofthefrontpanel.
1Safe EvacuationDistributed architecture interfaces directly with the Vigilon systemdeliveringhighquality, intelligiblevoicemessagestoreduceconfusionandpanic.
2Ideal for large Multi-storey Premises System can be networked, with a central Audio Control Unit (ACU)controllingupto30DistributedAmplifierUnits(DAU).
3Save on Space Fullyfeaturedwallmountedcontrolpanel,easiertoaccommodatethanconventionalracksystems.
4Simple Configuration and UpgradesAll functionssoftwareconfigurablewithnohardware linksetc toset.Configuration can be readily archived and restored. Functionalityupgradesinvolveonlysoftwarenothardware.
5Full Compliance with Relevant StandardsCompliesfullywithBS5839Part8,whichiswidelycalledforinprojectspecifications.
6Easy to MaintainDetailed full system fault status can be viewed at the central ACU,meaning that remoteunitsdonotneed tobe inspected todiagnosetheexactfault.
7System ReliabilityThe network is tolerant to open or short circuit faults between anytwo units on data or audio busses, automatically recovering andpinpointing the location of the fault. Even if all the processors inthe system fail, an All-Call announcement is still possible from theACUEmergencyMicrophone.
8Site Wide Audio Synchronisation3 audio channels plus data, allows simultaneous distribution of AlertandEvacuationmessagestoallowsitewideaudiosynchronisation inadditiontoEmergencyMicrophoneaudio.Whennoemergencyaudioispresentthesechannelsmaysupportroutinepagingorbackgroundmusicfunctions.
9No Data DegradationDataisre-clockedateachDAUtoensurethereisnodatadegradationasthesizeofthesystemincreases.
10Peace of MindEstablished market leader in fire detection, delivering innovativesolutions to ensure safe evacuation even in the most acousticallychallengingapplications.
10 Reasons to Specify Vigilon Voice
Section 7.2: Gent by Honeywell Voice Solutions
by Honeywell
SECTION 7: page ��
XLSPAVA Range
Section 7.3: Honeywell Voice Solutions
Introduction
A simple, intuitive touchscreen humaninterface eases routine use. Operationiseasy,despitethesophisticatedaudioand control processing which providesunparalleledsystemflexibility.
Highlights
l HighintegrityserialdatalinktoXLS80efirepanel
l DesignedforBS5839Part8andBSEN60849compliance
l ThirdpartyapprovaltoEN60849
l Loudspeakersurveillancedoesnotrequireacapacitortobefittedtoeachloudspeaker
l Totalcriticalpathsurveillance
l Flexiblevoicealarmandpublicaddressfunctionality
l High-integrity,flexibleandreliableprocessor-basedsystem
l Auto-learnamplifierandloudspeakercircuitcommissioning
l Uniquefullymonitoredtouchscreenmicrophonetechnology
Emergency and public addresstouchscreen microphones are availabletoaccessupto96zone/zonegroups.
Fullpassword-protectedcontrolofdigitalmessagebroadcast ispossible,andtheunitdisplaysbothzoneactivityanddetailedfaultstatus.Amonitor loudspeakeractsas both broadcast monitor and faultsounder. More conventional pagingmicrophonesarealsoavailable,featuringoneorfourzonecapacity.
Routers
Controlling zones in groups of four,the router range allows systems to becreated, from the simplest to themostcomplex. All configuration is carriedout using a PC tool, and the finalcommissioning settings can be easilysavedforarchiving.Theroutersincludedigital message capability and alsomonitor the connected amplifiers andloudspeakercircuits.
Amplifiers
Themodularrangeofamplifierscomesin 60W, 120W and 240W blocks tosuit most applications. Fully monitoredstandbyamplifierscanalsobeincludedtoensurefullcompliance.
1Superior Audio QualityDesignedforbothspeechandmusic,thelowdistortion,highbandwidthrange provides both high quality entertainment or background musicbroadcastsandclear,intelligibleliveandpre-recordedspokenmessages.
2Serial Data link to XlS80e Replacingmultiplemodulesandcables,theserial linkprovidesafullymonitored and configurable method to initiate emergency messagereplay, allowing changes to be made where necessary withoutadditionalequipment.
3Touchscreen Microphones The fully monitored touchscreen microphone range provides thecontrolandindicatingfunctionsforthesystem,allowinganoperatortomakezonedannouncements(bothliveandpre-recorded)andcontrolbackground music replay, including music level controls and sourceselectionperzone.
4Flexible loudspeaker Circuit SurveillanceThe impedance/end-of-line surveillance system does not require anymonitoring components to be fitted to each loudspeaker, such ascapacitors, thereforegreatly simplifying theupgradepath for existingsystemsandretrofitprojects.
5Comprehensive Audio Processing OptionsThesystemprovidesthree-bandparametricequalisationoneachinput,and seven-band parametric equalisation with programmable delayoneachzoneoutput,providingtheaudiotoolstogetthebestoutofthe system.Sophisticated ambient noise sensing and control is alsoavailableasanoption.
6Scalable Solutions Connect up to 64 IDA series routers together and retain control onlarge or complex sites. New buildings or extensions are also easilyaccommodatedontotheexistingsystem.
7Simple Windows-based PC Configuration ToolAllcommissioningconfigurationiscarriedoutusingaPCtool,preventingun-authorisedfront-paneladjustmentofsystemsettings.
8Flexible Pre-recorded Message StructurePre-recorded messages are stored with no single message durationlimit (subject to the system’s total capacity) so short messages donot reduce capacity further than their actual message length. Acomprehensive internal message scheduler allows timed messagereplayforsecurityandadvertisingpurposes.
10Peace of MindEstablished market leader in fire detection, delivering innovativesolutions to ensure safe evacuation even in the most acousticallychallengingapplications.
SECTION 7: page 20
Section 7.4: Speakers
Cabinet Loudspeakers
TECHNICAl SPECIFICATION
Type Moulded Cabinet Speaker Vandal-proof Cabinet Speaker
Estimated standard deviation in total level = 0.5dBA Estimated minimum Signal-to-Noise Ratio = 31dBABd0 = tnemtsujda level tnarebreveRABd4.1 = level tcerid ni noitaived dradnatS
STI Prediction Summary
STIrMap Colour Keys
Lw (@ Prediction Level) [dB re Simulation Spectrum]Loudspeaker Model/Type
The table illustrates the prediction summary of the anticipated