FactSheetTheImportanceofRootCauseAnalysisDuringIncidentInvestigationTheOccupationalSafetyandHealthAdministration(OSHA)andtheEnvironmentalProtectionAgency(EPA)urgeemployers(ownersandoperators)toconductarootcauseanalysisfollowinganincidentornearmissatafacility.1Arootcauseisafundamental,underlying,system-relatedreasonwhyanincidentoccurredthatidentifiesoneormorecorrectablesystemfailures.2Byconductingarootcauseanalysisandaddressingrootcauses,anemployermaybeabletosubstantiallyorcompletelypreventthesameorasimilarincidentfromrecurring.OSHAProcessSafetyManagementandEPARiskManagementProgramRequirementsEmployerscoveredbyOSHA’sProcessSafetyManagement(PSM)standardarerequiredtoinvestigateincidentsthatresultedin,orcouldreasonablyhaveresultedin,catastrophicreleasesofhighlyhazardouschemicals.3Similarly,ownersoroperatorsoffacilitiesregulatedunderEPA’sRiskManagementProgram(RMP)regulationsmustconductincidentinvestigations.4Duringanincidentinvestigation,anemployermustdeterminewhichfactorscontributedtotheincident,andbothOSHAandtheEPAencourageemployerstogobeyondtheminimuminvestigationrequiredandconductarootcauseanalysis.Arootcauseanalysisallowsanemployertodiscovertheunderlyingorsystemic,ratherthanthegeneralizedorimmediate,causesofanincident.Correctingonlyanimmediatecausemayeliminateasymptomofaproblem,butnottheproblemitself.HowtoConductaRootCauseAnalysisAsuccessfulrootcauseanalysisidentifiesallrootcauses—thereareoftenmorethanone.Considerthefollowingexample:Aworkerslipsonapuddleofoilontheplantfloorandfalls.Atraditionalinvestigationmayfindthecausetobe“oilspilledonthefloor”withtheremedylimitedtocleaningupthespillandinstructingtheworkertobemorecareful.5Arootcauseanalysiswouldrevealthattheoilonthefloorwasmerelyasymptomofamorebasic,orfundamentalproblemintheworkplace.Anemployerconductingarootcauseanalysistodeterminewhethertherearesystemicreasonsforanincidentshouldask:–Whywastheoilonthefloorinthefirstplace?–Weretherechangesinconditions,processes,ortheenvironment?–Whatisthesourceoftheoil?–Whattaskswereunderwaywhentheoilwasspilled?–Whydidtheoilremainonthefloor?–Whywasitnotcleanedup?–Howlonghaditbeenthere?–Wasthespillreported?6Itisimportanttoconsiderallpossible“what,”“why,”and“how”questionstodiscovertherootcause(s)ofanincident.Inthiscase,arootcauseanalysismayhaverevealedthattherootcauseofthespillwasafailuretohaveaneffectivemechanicalintegrityprogram—thatincludesinspectionandrepair—thatwouldpreventordetectoilleaks.Incontrast,ananalysisthatfocusedonlyontheimmediatecause(failuretocleanupthespill)wouldnothavepreventedfutureincidentsbecausetherewasnosystemtoprevent,identify,andcorrectleaks.ProperlyframingandconductingarootcauseinvestigationisimportantforaPSMorRMP-relatedincident.Take,forexample,anincidentinvolvinganoverfillandsubsequentleakofhydrocarbonsfromareliefvalvesystemthatignitesandkillsmultipleworkers.Priortothisfatalincident,thereweremultipleflammablereleasesfromthereliefvalvesystem,butnoneignited.Theemployerpreviouslyperformedincidentinvestigationsonthenon-lethalinci-dentsanddeterminedthatoperatorerrorwasthecauseoftheoverfillsandsubsequentleaks.However,aproperrootcauseinvestigationwouldhavelookeddeeperintotheincident,anddeterminedthatfundingcuts—whichresultedinadeficientmechanicalintegrityprogramandmalfunctioninginstrumentation—ledtoadangeroussituationthatoperatorscouldnothave...
