RG1.047 安全系统的旁通和不可操作状态指示 1973

A.INTRODUCTIONCriterionXIV,Inspection,Test,andOperatingStatus,ofAppendixBto10CFRPart50,QualityAssuranceCriteriaforNuclearPowerPlantsandFuelReprocessingPlants,requiresthatmeasuresbeestablishedforindicatingtheoperatingstatusofstructures,systems,andcomponentsofthenuclearpowerplant,suchasbytaggingvalvesandswitches,topreventinadvertentoperation.Section50.55a,CodesandStandards,of10CFRPart50,requiresinParagraph(h)thatprotectionsystemsmeettherequirementssetforthintheInstituteofElectricalandElectronicsEngineersCriteriaforNuclearPowerPlantProtectionSystems(IEEE279).'Section4.13ofIEEEStd279-1971,CriteriaforProtectionSystemsforNuclearPowerGeneratingStations,'(alsodesignatedANSIN42.7-1972)requiresthat,iftheprotectiveactionofsomepartoftheprotectionsystemhasbeenbypassedordeliberatelyrenderedinoperativeforanypurpose,thisfactshallbecontinuouslyindicatedinthecontrolroom.ThisguidedescribesanacceptablemethodofcomplyingwiththerequirementsofIEEEStd279-1971andAppendixBto10CFRPart50withregardtoindicatingtheinoperablestatusofaportionoftheprotectionsystem(asdefinedinIEEEStd279-1971),systemsactuatedorcontrolledbytheprotectionsystem,andauxiliaryorsupportingsystemsthatmustbeoperablefortheprotectionsystemandthesystemsitactuatestoperformtheirsafety-relatedfunctions.TheAdvisoryCommitteeonReactorSafeguardshasbeenconsultedconcerningthisguideandhasconcurredintheRegulatoryposition.'CopiesmaybeobtainedfromtheInstituteofElectricalandElectronicsEngineers,UnitedEngineeringCenter,345East47thStreet,NewYork,N.Y.10017.May1973IDEB.DISCUSSIONCurrentdesignsofprotectionsystemsandengineeredsafetyfeaturesystemsaresuchthatcertainsafety-relatedfunctionsofanuclearpowerplantmaybebypassedormadeinoperableduringtheperformanceofperiodictestsormaintenance.2Generally,theplant'sadministrativeproceduresrequirethattheoperator'spermissionbeobtainedpriortoinitiatinganyactivitythatwouldorcouldaffectasafety-relatedsystem.Thedecisiontograntsuchpermissionshouldbebasedonaknowledgeoftheoperatingstatusofthesafety-relatedsystems,theextenttowhichtheactivitywillaffectthosesystems,andwhetherthateffectispermissiblewithintheprovisionsofthelicense.Experiencesatoperatingplants,however,indicatethat,whenthemeasuresusedtoindicateinoperablestatusconsistsolelyofadministrativeprocedures,theoperatorisnotalwaysfullyawareoftheramificationsofeachbypassedorinoperablecomponent.Anacceptablewayofaidingtheoperator'sknowledgeofplantstatusistosupplementadministrativeprocedureswithautomaticindicationofMhebypassorinoperabilityofeachredundantportionofasystemthatperformsafunctionimportanttosafety.Itisrecognizedthatautomaticindicationofinoperabilityorabypassedconditionisnotfeasibleforallthepossiblemeansby.whichsafety-relatedsystemscouldbecompletelyorpartiallyrenderedinoperative.Apracticalindicatingsystemcoveringawiderangeofcommonlyexpectedconditions,however,couldbedesignedifitincludedprovisionsforautomaticindicationofeachbypassordeliberatelyinducedinoperableconditionthatmeetsallthreeofthefollowingguidelines:IRegulatoryGuide1.22(SafetyGuide22),PeriodicTestingofProtectionSystemActuationFunctions,providesguidancethatshouldbeconsideredindesigningsystemsthatrequirebypassingaprotectiveactioninordertoperformperiodictests.USAECREGULATORYGUIDESCopiesofpublishedguidesmaybeobtainedbyrequestindicatingthedivisionsdesiredtotheU.S.AtomicEnergyCommission,Washington,D.C.20545,RegulatoryGuidesareissuedtodescribeandmakeavailabletothepublicAttention:DirectorofRegulatoryStandards.CommentsandsuggestionsformethodsacceptabletotheAECRegulatorystaffofimplementingspecificpartsofImprovementsintheseguidesareencouragedandshouldbesenttotheSecretarytheCommission'sregulations,todelineatetechniquesusedbythestaffinoftheCommission,U.S.AtomicEnergyCommission,Washiniton,D.C.20545,evluatingspecificproblemsorpostulatedaccidents,ortoprovideguidancetoAttention:Chief,PublicProceedingsStaff.applicants.RegulatoryGuidesarenotsubstitutesforregulationsandcompliancewiththemisnotrequired.MethodsandsolutionsdifferentfromthosesetoutinTheguidesareissuedinthefollowingtenbroaddivisions:theguideswillbeacceptableiftheyprovideabaisforthefindingsrequisitetotheissuanceorcontinuanceofapermitorlicensebytheCommission.1.PowerReactors6.Products2.ResearchandTestReactors7.Transportation3.FuelsandMaterialsFacilities8.OccupationalHealthPublishedguideswillberevisedperiodically,asappropriate,toaccommodate4.EnvironmentalandSiting8.AntitrustReviewcommentsandtoreflectnewinformationorexperience.5.MaterialsandPlantProtection10.GeneralS.U.S.ATOMICENERGYCOMMISSIONSREGULATORYGUIDIRECTORATEOFREGULATORYSTANDARDSREGULATORYGUIDE1.47BYPASSEDANDINOPERABLESTATUSINDICATIONFORNUCLEARPOWERPLANTSAFETYSYSTEMS1.Thebypassorinoperableconditionaffectsasystemthatisdesignedtoperformautomaticallyafunctionthatisimportanttothesafetyofthepublic;2.Thebypasswillbeutilizedbyplantpersonnelortheinoperableconditioncanreasonablybeexpectedtooccurmorefrequentlythanonceperyear;and3.Thebypassorinoperableconditionisexpectedtooccurwhentheaffectedsystemisnormallyrequiredtobeoperable.Suchadesignisconsideredpracticalbecau