osha教材-scaffolds 脚手架

OSHAOfficeofTraining&Education1ScaffoldsOSHAOfficeofTraining&Education2WhatIsAScaffold?Anelevated,temporaryworkplatformThreebasictypes:Supportedscaffolds--platformssupportedbyrigid,loadbearingmembers,suchaspoles,legs,frames,&outriggersSuspendedscaffolds--platformssuspendedbyropesorothernon-rigid,overheadsupportAerialLifts--suchas“cherrypickers”or“boomtrucks”OSHAOfficeofTraining&Education3Hazards•Fallsfromelevation–causedbyslipping,unsafeaccess,andthelackoffallprotection•Struckbyfallingtools/debris•Electrocution–fromoverheadpowerlines•Scaffoldcollapse-causedbyinstabilityoroverloading•BadplankinggivingwayEmployeesworkingonscaffoldsareexposedtothesehazards:OSHAOfficeofTraining&Education4FallHazards•Whileclimbingonoroffthescaffold•Workingonunguardedscaffoldplatforms•WhenscaffoldplatformsorplanksfailFallsmayoccur:OSHAOfficeofTraining&Education5ProtectingWorkersfromFalls•Guardrails,and/or•PersonalFallArrestSystems(PFAS)Ifaworkeronascaffoldcanfallmorethan10feet,protectthemby:OSHAOfficeofTraining&Education6Installalongopensides&endsFrontedgeofplatformsnotmorethan14inchesfromthework,unlessusingguardrailsand/orPFASToprails-38to45inchestallMidrailshalfwaybetweentoprailandplatformToeboardsatleast3-1/2incheshighGuardrailsOSHAOfficeofTraining&Education7PersonalFallArrestSystems(PFAS)YoumustbetrainedhowtoproperlyusePFASPFASincludeanchorage,lifelineandbodyharness.OSHAOfficeofTraining&Education8CanusePFASinsteadofguardrailsonsomescaffoldsUsePFAS&guardrailsonsuspensionscaffoldsUsePFASonerectorsanddismantlerswherefeasibleFallProtectionRequirementsTheendsofthisscaffoldarenotproperlyguardedOSHAOfficeofTraining&Education9FallingObjectProtectionWearhardhatsBarricadeareabelowscaffoldtoforbidentryintothatareaUsepanelsorscreensifmaterialisstackedhigherthanthetoeboardBuildacanopyorerectanetbelowthescaffoldthatwillcontainordeflectfallingobjectsOSHAOfficeofTraining&Education10OverheadPowerLinesThepossibilityofelectrocutionisaseriousconsiderationwhenworkingnearoverheadpowerlinesChecktheclearancedistanceslistedinthestandardOSHAOfficeofTraining&Education11ScaffoldSupportExamplesGoodsupportInadequatesupport–indangerofcollapse?BaseplateMudsillsOSHAOfficeofTraining&Education12EssentialElementsofSafeScaffoldConstruction•Useappropriatescaffoldconstructionmethods•Properscaffoldaccess•ProperlyuseacompetentpersonOSHAOfficeofTraining&Education13ScaffoldPlatformConstructionPlatformsmust:•befullyplankedordeckedwithnomorethan1inchgaps•beabletosupportitsweight&4timesmaximumload•beatleast18incheswideThisisnotaproperlyconstructedscaffoldOSHAOfficeofTraining&Education14•Nolargegapsinfrontedgeofplatforms•Eachabuttedendofplankmustrestonaseparatesupportsurface•Overlapplatformsatleast12inchesoversupports,unlessrestrainedtopreventmovementScaffoldPlatformConstructionPlanksnotproperlyoverlappedOSHAOfficeofTraining&Education15ScaffoldPlatformConstruction•Nopaintonwoodplatforms•Usescaffoldgradewood•Fullyplankedbetweenfrontuprightandguardrailsupport•Componentpiecesusedmustmatchandbeofthesametype•Erectonstableandlevelground•LockwheelsandbracesOSHAOfficeofTraining&Education16ScaffoldHeightTheheightofthescaffoldshouldnotbemorethanfourtimesitsminimumbasedimensionunlessguys,ties,orbracesareused20’5’OSHAOfficeofTraining&Education17PlatformEndsEachendofaplatform,unlesscleatedorotherwiserestrainedbyhooks,mustextendoveritssupportbyatleast6inchesNoCleatsOSHAOfficeofTraining&Education18SupportedScaffoldsPlatformssupportedbylegs,outriggerbeams,brackets,poles,uprights,posts,&framesRestrainfromtippingbyguys,ties,orbracesScaffoldpoles,legs,posts,frames,anduprightsmustbeonbaseplatesandmudsillsorotherfirmfoundationThissupportisnotadequate!OSHAOfficeofTraining&Education19ProperScaffoldAccessProvideaccesswhenscaffoldplatformsaremorethan2feetaboveorbelowapointofaccessPermittedtypesofaccess:•Ladders,suchasportable,hook-on,attachable,stairwaytype,andbuilt-ins•Stairtowers•RampsandwalkwaysMayusebuildingstairsandcomeoutwindowOSHAOfficeofTraining&Education20ScaffoldAccess•Noaccessbycrossbraces•Whenusingladders,bottomrungnomorethan24incheshigh•Canusesomeendframes•Canaccessfromanotherscaffold,structureorhoistEndFrameDonotaccessbycrossbracesOSHAOfficeofTraining&Education21SuspensionScaffoldsTrainemployeestorecognizehazardsSecure/tietopreventswayingSupportdevicesmustrestonsurfacesthatcansupportfourtimestheloadCompetentperson:evaluateconnectionstoensurethesupportingsurfacescansupportloadinspectropesfordefectsbeforeshiftPFASmusthaveanchorsindependentofthescaffoldsupportsystemPlatformssuspendedbyropesorwires.Ropemustbecapableofsupporting6timestheloadOSHAOfficeofTraining&Education22MovingScaffoldsEmployeescan’tbeonamovingscaffoldunless:•Surfaceislevel•Heighttobaseratiois2to1•OutriggersareinstalledonbothsidesofscaffoldsEmployeescan’tbeonscaffoldpartbeyondthewheelsCompetentpersonmustbeonsitetosuperviseOSHAOfficeofTraining&Education23FatalFact–MovingaLiftEmployeewasoperatinganaeriallift,withanextendableboomrotatingworkplatformTheboomwasfullyextendedandthemachineapparentlyranoversomebricks