Author/Authors :
E.Baumann، نويسنده , , I.R.Terry، نويسنده ,
Abstract :
FortheEuropeanPressurizedWaterReactor(EPR)alargeeffortwasmadetoimprovetheplantdesignwithrespecttoradiationprotectionusingtheexperiencegainedduringthedesignofformergenerationsofpressurizedwaterreactor(PWR)inFranceandGermany,andtheircurrentoperation.KeepingtheradiationexposureofpersonneltoanacceptablelevelisoneofthemainobjectivesoftheEPRdesign.Boththeindividualandthecollectivedosesareconsidered.
InternationallycomparablelimitsbasedonrecommendationsoftheInternationalCommissiononRadiologicalProtection(ICRP)havebeenestablishedforindividualdoses.Theselimitsdescribetheframeworkwithinwhichtheindividualdoseshallbekeptaslowaspossible,applyingtheprinciples:
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Justification:Nopracticeinvolvingexposurestoradiationshouldbeadoptedunlessitproducessufficientbenefittotheexposedindividualsortosocietytooffsettheradiationdetrimentitcauses.
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Optimization:Inrelationtoanyparticularsourcewithinapractice,themagnitudeofindividualdoses,thenumberofpeopleexposed,andthelikelihoodofincurringexposureswherethesearenotcertaintobereceivedshouldallbekeptaslowasreasonablyachievable(ALARA),economicandsocialfactorsbeingtakenintoaccount.
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Limitation:Theexposureofindividualsresultingfromthecombinationofalltherelevantpracticesissubjecttodoselimits.
Thepaperdescribesthedesignprovisionandmeasuresintroducedintheplantdesigntoachievetheabovedescribedgoals.
Theyareinessence:
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measurestoavoidortoreducesourcesofradiation;
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layoutaspects;
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provisionsmadeinthecomponentdesignwithrespecttoeaseofoperationandmaintenancemanagement;
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improvedpossibilitiesofdecontamination;
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useofoperatingexperiencefordesignimprovements.
TheradiationprotectionlayoutprinciplescompiledonthebasisofsafeoperatingexperiencegainedfromtheexistingpressurizedwaterreactorsinFranceandGermanyareusedtodevelopanimprovedplantdesignwithrespecttoradiationprotectionaspectsanddoseoptimization.
Summary:TheEuropeanPressurizedWaterReactorisanevolutionarythird-generationpressurizedwaterreactorwitharatinginthe1600MWeclass.Itsdevelopmentwasstartedin1992byFramatomeandSiemens,whosenuclearactivitieswerecombinedinJanuary2001toformFramatomeANP,nowAREVANP.BeingtheproductofintensebilateralcooperationtheEPRcombinesthetechnologicalaccomplishmentsoftheworldʹstwoleadingPWRproductlines—theFrenchN4reactorsinoperationatChoozandCiveauxandtheKonvoireactorsinoperationatNeckarwestheim,EmslandandIsarinGermany.Fromtheverystart,developmentoftheEPRwasfocusedonimprovingplantsafetyandeconomicsevenfurtherandalsoalargeeffortwasmadetoimprovetheplantdesignwithrespecttoradiationprotection.KeepingthedosesreceivedbyoperatingandmaintenancepersonneltoalevelfarbelowthelimitingvalueswasoneofthemainobjectivesoftheEPRdesign.Boththeindividualandthecollectivedosesareconsideredinthisarticle.