NuAire Labgard NU-430-400 User Manual

OM0228 Page33of99
February/2014
6.2.4 UtilizeUnidirectionalAirflow
Theoperatormustkeeptwoimportantfactsinmind:(1)Theairassuppliedtotheworkareathroughfiltersfrom
thetop,iscontaminantfreeand(2)Airbornecontaminationgeneratedintheworkareaiscontrolledbythe
unidirectionalflowofparallelairstreamsinatop‐to‐bottomdirection.
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Asolidobjectplacedinalaminarairstreamwilldisrupttheparallelflowandconsequently,thecapabilityof
controllinglateralmovementofairborneparticulates.Aconeofturbulenceextendsbelowtheobjectand
laminarityoftheairstreamisnotregaineduntilapointisreacheddownstream,approximatelyequaltothreeto
sixtimesthediameteroftheobject.Withintheparametersofthiscone,particlesmaybecarriedlaterallyby
multidirectionaleddycurrents.
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Transferofviablematerialsandmanipulations,whichmaygenerateaerosols,shouldnotbeperformedabove
sterileoruninoculatedmaterials.Itemsshouldbelocalized ontheworksurfacein"clean"and"dirty"groups.
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6.2.5 Emp
loyAsepticTechnique
Theoperatormustnotassumeanattitudeof"letthecabinetdoit"whenperformingprocedureswithinaLFBSC.
Properlybalancedandproperlyusedcabinetswilldoanexcellentjobofcontrollingairbornecontaminationand
containingviableagents,butthecabinetwillnoteliminatecontacttransmissionofcontamination.Normal
laboratorycontaminationcontrolproceduresandbasicaseptictechniquesarenecessarytoobtainmaximum
benefitfromthecabinet.Forexamples,openbottle,tubeorflaskmountsshouldbekeptasparallelaspossibleto
thedownflowtominimizecaptureofchanceparticulates.Thisprecautionismerelyanextensionofgoodaseptic
techniqueaspracticedonopenbenchtops.Thegoodlaboratorypracticesdesignedtominimizecreationand/or
releaseofaerosolstotheenvironmentshouldnotbediscontinued.
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Itemsofequipmentindirectcontactwiththeetiologicagentmustremaininthecabinetuntilenclosedoruntil
surface‐decontaminated.Traysofdiscardpipettesmustbecoveredbeforeremovalfromthecabinet(aluminum
foilmaysubstituteforfabricatedcovers).
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Ifanaccidentoccurswhichspillsorsplatterssuspensionsofetiologicagentaroundtheworkarea,allsurfacesand
itemsinthecabinetmustbesurface‐decontaminatedbeforebeingremoved.
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Applyingaburnerflametoflaskandtubeneckswhenmatingsurfacesofsterileassembliesisaconventional
methodofminimizingchancecontamination.However,theefficiencyofthisoperationisusuallyrelatedtothe
removalofairbornecontaminationoccurringwhiletheitemisuncovered.Ifthemanipulationiscarriedoutinan
environmentfreeofairborneparticulates,thentheneedfortheflamingoperationisessentiallyremoved.
ThisisoneoftheadditionaladvantagesoftheLFBSC‐useofthegasburnerisseldomnecessary.
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Thegasburnerflameinoneofthesecabinetsnotonlycontributessignificantlytotheheatbuild‐up;italso
disruptsthelaminarairstreams,whichmustbemaintainedformaximumefficiency.IFTHEPROCEDURE
DEMANDSUSEOFAFLAME,ABUNSE
NBURNERWITHONDEMANDIGNITIONISRECOMMENDED.DONOTUSE
CONSTANTFLAMEGASBURNERS.Itshouldalsobeonlyusedfromthecenteroftheworksurfacetotheright
rearwhereresultingairturbulencewillhaveaminimaleffect.DONOTUSEGASBURNERONTHELE
FTOFTHE
WORKSURFACEDUETOITSINFLUENCEONTHEELECTRONICAIRFLOWCONTROLSYSTEM.Ifcabinetairis
inadvertentlyturnedoff,theflamecoulddamagetheHEPAfilters.
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NuAire Labgard NU-430-400 Specifications

General

Brand	NuAire
Model	Labgard NU-430-400
Category	Air Conditioner
Language	English