RG1.200 风险预知活动的概率风险评估结构的技术充分性确定的一个方法 2009

U.S.NUCLEARREGULATORYCOMMISSIONMarch2009Revision2REGULATORYGUIDEOFFICEOFNUCLEARREGULATORYRESEARCHREGULATORYGUIDE1.200(DraftwasissuedasDG-1200,datedJune2008)ANAPPROACHFORDETERMININGTHETECHNICALADEQUACYOFPROBABILISTICRISKASSESSMENTRESULTSFORRISK-INFORMEDACTIVITIESA.INTRODUCTIONIn1995,theU.S.NuclearRegulatoryCommission(NRC)issuedaPolicyStatement(Ref.1)ontheuseofprobabilisticriskanalysis(PRA),encouragingitsuseinallregulatorymatters.ThatPolicyStatementstatesthat“…theuseofPRAtechnologyshouldbeincreasedtotheextentsupportedbythestate-of-the-artinPRAmethodsanddataandinamannerthatcomplementstheNRC’sdeterministicapproach.”Sincethattime,manyuseshavebeenimplementedorundertaken,includingmodificationoftheNRC’sreactorsafetyinspectionprogramandinitiationofworktomodifyreactorsafetyregulations.Consequently,confidenceintheinformationderivedfromaPRAisanimportantissue,inthattheaccuracyofthetechnicalcontentmustbesufficienttojustifythespecificresultsandinsightsthatareusedtosupportthedecisionunderconsideration.ThisregulatoryguidedescribesoneacceptableapproachfordeterminingwhetherthetechnicaladequacyofthePRA,intotalorthepartsthatareusedtosupportanapplication,issufficienttoprovideconfidenceintheresults,suchthatthePRAcanbeusedinregulatorydecision-makingforlight-waterreactors.ThisguidanceisintendedtobeconsistentwiththeNRC’sPRAPolicyStatement.Itisalsointendedtoreflectandendorseguidanceprovidedbystandards-settingandnuclearindustryorganizations.Whenusedinsupportofanapplication,thisregulatoryguidewillobviatetheneedforanin-TheNRCissuesregulatoryguidestodescribeandmakeavailabletothepublicmethodsthattheNRCstaffconsidersacceptableforuseinimplementingspecificpartsoftheagency=sregulations,techniquesthatthestaffusesinevaluatingspecificproblemsorpostulatedaccidents,anddatathatthestaffneedsinreviewingapplicationsforpermitsandlicenses.Regulatoryguidesarenotsubstitutesforregulations,andcompliancewiththemisnotrequired.MethodsandsolutionsthatdifferfromthosesetforthinregulatoryguideswillbedeemedacceptableiftheyprovideabasisforthefindingsrequiredfortheissuanceorcontinuanceofapermitorlicensebytheCommission.Thisguidewasissuedafterconsiderationofcommentsreceivedfromthepublic.Regulatoryguidesareissuedin10broaddivisionsC1,PowerReactors;2,ResearchandTestReactors;3,FuelsandMaterialsFacilities;4,EnvironmentalandSiting;5,MaterialsandPlantProtection;6,Products;7,Transportation;8,OccupationalHealth;9,AntitrustandFinancialReview;and10,General.ElectroniccopiesofthisguideandotherrecentlyissuedguidesareavailablethroughtheNRC=spublicWebsiteundertheRegulatoryGuidesdocumentcollectionoftheNRC=sElectronicReadingRoomat=sAgencywideDocumentsAccessandManagementSystem(ADAMS)at(OMB)approvedunderOMBcontrolnumber3150-0011.TheNRCmayneitherconductnorsponsor,andapersonisnotrequiredtorespondto,aninformationcollectionrequestorrequirementunlesstherequestingdocumentdisplaysacurrentlyvalidOMBcontrolnumber.B.DISCUSSIONExistingGuidanceRelatedtotheUseofPRAinReactorRegulatoryActivitiesSincetheNRCissueditsPRAPolicyStatement,anumberofrisk-informedregulatoryactivitieshavebeenimplementedandthenecessarytechnicaldocumentsarebeingdevelopedtoprovideguidanceontheuseofPRAinformation.Fortheseactivities,thetechnicaladequacyofthebasePRAshouldbesufficienttoprovidetheneededconfidenceintheresultsbeingusedinthedecision.Alistofsomeofthesedocumentsisprovidedbelow.RegulatoryGuide1.174(Ref.2)anditsassociatedstandardreviewplan(SRP),Section19.2(Ref.3),providegeneralguidanceonapplicationsthataddresschangestothelicensingbasis.Keyaspectsofthisdocumentincludethefollowing:•Itdescribesa“risk-informedintegrateddecision-makingprocess”thatcharacterizeshowriskinformationisusedand,morespecifically,itclarifiesthatsuchinformationisoneelementofthedecision-makingprocess.Thatis,decisions“areexpectedtobereachedinanintegratedfashion,consideringtraditionalengineeringandriskinformation,andmaybebasedonqualitativefactorsaswellasquantitativeanalysesandinformation.”•Itreflectsthestaff’srecognitionthatthePRAneededtosupportregulatorydecisionscanvary(i.e.,thatthe“scope,levelofdetail,andqualityofthePRAistobecommensuratewiththeapplicationforwhichitisintendedandtherolethePRAresultsplayintheintegrateddecisionprocess”).Forsomeapplicationsanddecisions,onlyparticularpieces1ofthePRAneedtobeused.Inotherapplications,afull-scopePRAisneeded.Generalguidanceregardingscope,levelofdetail,andqualityforaPRAis