osha教材-excavations 挖掘安全

OSHAOfficeofTrainingandEducation1ExcavationsOSHAOfficeofTrainingandEducation2ExcavationHazardsCave-insarethegreatestriskOtherhazardsinclude:AsphyxiationduetolackofoxygenInhalationoftoxicmaterialsFireMovingmachineryneartheedgeoftheexcavationcancauseacollapseAccidentalseveringofundergroundutilitylinesOSHAOfficeofTrainingandEducation3InjuryandDeath•Excavatingisoneofthemosthazardousconstructionoperations•Mostaccidentsoccurintrenches5-15feetdeep•Thereisusuallynowarningbeforeacave-inOSHAOfficeofTrainingandEducation4Definitions•Excavation–aman-madecut,cavity,trench,ordepressionformedbyearthremoval.•Trench–anarrowexcavation.Thedepthisgreaterthanthewidth,butnotwiderthan15feet.•Shield-astructureabletowithstandacave-inandprotectemployees•Shoring-astructurethatsupportsthesidesofanexcavationandprotectsagainstcave-ins•Sloping-atechniquethatemploysaspecificangleofinclineonthesidesoftheexcavation.Theanglevariesbasedonassessmentofimpactingsitefactors.OSHAOfficeofTrainingandEducation5FocusofTraining•Thegreatestriskatanexcavation•Howtoprotectemployeesfromcave-ins•Factorsthatposeahazardtoemployeesworkinginexcavations•TheroleofacompetentpersonatanexcavationsiteOSHAOfficeofTrainingandEducation6ProtectionofEmployeesEmployeesshouldbeprotectedfromcave-insbyusinganadequatelydesignedprotectivesystemProtectivesystemsmustbeabletoresistallexpectedloadstothesystemOSHAOfficeofTrainingandEducation7RequirementsforProtectiveSystemsAwell-designedprotectivesystemCorrectdesignofslopingandbenchingsystemsCorrectdesignofsupportsystems,shieldsystems,andotherprotectivesystemsPlusAppropriatehandlingofmaterialsandequipmentPlusAttentiontocorrectinstallationandremovalEqualsProtectionofemployeesatexcavationsOSHAOfficeofTrainingandEducation8DesignofProtectiveSystemsTheemployershallselectandconstruct:slopesandconfigurationsofslopingandbenchingsystemssupportsystems,shieldsystems,andotherprotectivesystems•Shield-canbepermanentorportable.Alsoknownastrenchboxortrenchshield.•Shoring-suchasmetalhydraulic,mechanicalortimbershoringsystemthatsupportsthesides•Sloping-formsidesofanexcavationthatareinclinedawayfromtheexcavationOSHAOfficeofTrainingandEducation9ProtectEmployeesExposedtoPotentialCave-insSlopeorbenchthesidesoftheexcavation,Supportthesidesoftheexcavation,orPlaceashieldbetweenthesideoftheexcavationandtheworkareaOSHAOfficeofTrainingandEducation10Cave-inHazardThisexcavationhasinadequatesupportpostsandegressaccessInadequateprotectivesystemOSHAOfficeofTrainingandEducation11InadequateProtectiveSystemThisworkerisinatrenchwithnoprotectivesystem,thatisnotslopedorbenchedandhasnomeansofegressOSHAOfficeofTrainingandEducation12FactorsInvolvedinDesigningaProtectiveSystemSoilclassificationDepthofcutWatercontentofsoilChangesduetoweatherandclimateOtheroperationsinthevicinityOSHAOfficeofTrainingandEducation13Shoring•GeneralProvidesaframeworktoworkinUseswales,crossbracesanduprightsSupportsexcavationwalls•OSHAtablesprovideshoringdataMustknowsoiltypeMustknowdepthandwidthofexcavationMustbefamiliarwiththeOSHATablesOSHAOfficeofTrainingandEducation14TrenchShieldAtrenchshieldwasbuiltaroundthisworkareaOSHAOfficeofTrainingandEducation15HydraulicTrenchSupport•Usinghydraulicjackstheoperatorcaneasilydropthesystemintothehole•Onceinplace,hydraulicpressureisincreasedtokeeptheformsinplace•TrenchpinsareinstalledincaseofhydraulicfailureOSHAOfficeofTrainingandEducation16MaterialsandEquipment•Equipmentusedforprotectivesystemsmustnothavedamageordefectsthatimpairfunction.•Ifequipmentisdamaged,thecompetentpersonmustexamineittoseeifitissuitableforcontinueduse.•Ifnotsuitable,removeitfromserviceuntilaprofessionalengineerapprovesitforuse.OSHAOfficeofTrainingandEducation17ProtectionfromVehicles•Installbarricades•Hand/mechanicalsignals•Stoplogs•Gradesoilawayfromexcavation•FenceorbarricadetrenchesleftovernightOSHAOfficeofTrainingandEducation18HazardousConditionsTheweightandvibrationsofthecranemakethisaveryhazardouscondition.Theyshouldnotbeworkingunderthiscrane.OSHAOfficeofTrainingandEducation19Spoils•Don’tplacespoilswithin2feetfromedgeofexcavation•Measurefromnearestpartofthespoiltotheexcavationedge•Placespoilssorainwaterrunsawayfromtheexcavation•PlacespoilwellawayfromtheexcavationOSHAOfficeofTrainingandEducation20OtherExcavationHazardsWateraccumulationOxygendeficiencyToxicfumesAccess/EgressFallsMobileequipmentOSHAOfficeofTrainingandEducation21WaterisHazardousWhenwaterispresentinanexcavationitisextremelyhazardoustoenterNotethattheseworkersarenotwearinghardhatstoprotectthemfrommaterialsfallingintothetrenchOSHAOfficeofTrainingandEducation22Water=Cave-inHazardTheseworkersmustbeprotectedfromcave-in.Notethewaterinthebottomofthetrench.Thisisaveryhazardouscondition!OSHAOfficeofTrainingandEducation23HazardousAtmosphereTestexcavationsmorethan4feetbeforeanemployeeenterstheexcavationfor:OxygendeficiencyHighcombustiblegasconcentrationHighlevelsofotherhazardoussubstancesOSHAOfficeofTrainingandEducation24MeansofEgressAstairway,ladder,orrampmustbepresentinexcavationsthatare4ormorefeetdeep,andw