EN 50126-2-2007 Part 2 Guide to the application of

PUBLISHEDDOCUMENTPDCLC/TR50126-2:2007Railwayapplications—ThespecificationanddemonstrationofReliability,Availability,MaintainabilityandSafety(RAMS)—Part2:GuidetotheapplicationofEN50126-1forsafetyICS45.020  PDCLC/TR50126-2:2007ThisPublishedDocumentwaspublishedundertheauthorityoftheStandardsPolicyandStrategyCommitteeon30April2007©BSI2007ISBN9780580504884NationalforewordThisPublishedDocumentwaspublishedbyBSI.ItistheUKimplementationofCLC/TR50126-2:2007.TheUKparticipationinitspreparationwasentrustedtoTechnicalCommitteeGEL/9,Railwayelectrotechnicalapplications.AlistoforganizationsrepresentedonGEL/9canbeobtainedonrequesttoitssecretary.Thispublicationdoesnotpurporttoincludeallthenecessaryprovisionsofacontract.Usersareresponsibleforitscorrectapplication.AmendmentsissuedsincepublicationAmd.No.DateCommentsTECHNICALREPORTCLC/TR50126-2RAPPORTTECHNIQUETECHNISCHERBERICHTFebruary2007CENELECEuropeanCommitteeforElectrotechnicalStandardizationComitéEuropéendeNormalisationElectrotechniqueEuropäischesKomiteefürElektrotechnischeNormungCentralSecretariat:ruedeStassart35,B-1050Brussels©2007CENELEC-AllrightsofexploitationinanyformandbyanymeansreservedworldwideforCENELECmembers.Ref.No.CLC/TR50126-2:2007EICS45.020EnglishversionRailwayapplications-ThespecificationanddemonstrationofReliability,Availability,MaintainabilityandSafety(RAMS)-Part2:GuidetotheapplicationofEN50126-1forsafetyApplicationsferroviaires-Spécificationetdémonstrationdelafiabilité,deladisponibilité,delamaintenabilitéetdelasécurité(FDMS)-Partie2:Guidepourl’applicationdel’EN50126-1àlasécuritéBahnanwendungen-SpezifikationundNachweisderZuverlässigkeit,Verfügbarkeit,Instandhaltbarkeit,Sicherheit(RAMS)-Teil2:LeitfadenzurAnwendungderEN50126-1fürSicherheitThisTechnicalReportwasapprovedbyCENELECon2007-01-22.CENELECmembersarethenationalelectrotechnicalcommitteesofAustria,Belgium,Bulgaria,Cyprus,theCzechRepublic,Denmark,Estonia,Finland,France,Germany,Greece,Hungary,Iceland,Ireland,Italy,Latvia,Lithuania,Luxembourg,Malta,theNetherlands,Norway,Poland,Portugal,Romania,Slovakia,Slovenia,Spain,Sweden,SwitzerlandandtheUnitedKingdom.ForewordTheEuropeanStandardEN50126-1:1999,whichwaspreparedjointlybytheTechnicalCommitteesCENELECTC9X,Electricandelectronicapplicationsforrailways,andCENTC256,Railwayapplications,undermode4co-operation,dealswiththespecificationanddemonstrationofReliability,Availability,MaintainabilityandSafety(RAMS)forrailwayapplications.AguidetotheapplicationofEN50126-1forsafetyofrailwaysystems(thisCLC/TR50126-2)andaguidefortheapplicationtoEN50126-1forrollingstockRAM(CLC/TR50126-3:2006)havebeenproducedtoforminformativepartsofEN50126-1:1999.WhilstthisCLC/TR50126-2isapplicabletoallrailwaysystems,includingrollingstock,CLC/TR50126-3:2006isapplicabletorollingstockRAMonly.ThisTechnicalReport,whichwaspreparedbyWG8oftheTechnicalCommitteeCENELECTC9X,formsaninformativepartofEN50126-1:1999andcontainsguidelinesfortheapplicationofEN50126-1forthesafetyofrailwaysystems.ThetextofthedraftwassubmittedtothevoteandwasapprovedbyCENELECasCLC/TR50126-2on2007-01-22.---------------–2–CLC/TR50126-2:2007ContentsIntroduction.......................................................................................................................................................81Scope...........................................................................................................................................................92References................................................................................................................................................113Definitionsandabbreviations.................................................................................................................123.1GuidanceontheinterpretationoftermsanddefinitionsusedinEN50126-1.................................123.2Additionalsafetyterms.....................................................................................................................153.3Abbreviations....................................................................................................................................174Guidanceonbodies/entitiesinvolvedandconceptsofsystemhierarchyandsafety.....................174.1Introduction.......................................................................................................................................174.2Bodies/entitiesinvolvedinasystem.................................................................................................184.3Conceptsofsystemhierarchy..........................................................................................................184.3.1Railtransportsystemenvironmentandsystemhierarchy..................................................194.4Safetyconcepts................................................................................................................................194.4.1Hazardperspective....................................................