21–121SCAFFOLDSContents1.Introduction2.Problemareas3.Selection4.Basictypesofscaffolds5.Scaffoldcomponents6.Erectinganddismantlingscaffolds7.Scaffoldstability8.Platforms9.Properuseofscaffolds1INTRODUCTIONMorethanhalfofscaffoldaccidentsinOntarioconstructionarefalls.Severalfatalitiesarealsorelatedtoscaffoldseachyear.Thenumberandseverityofinjuriesinvolvedmakescaffoldaccidentsoneofthemoreserioussafetyproblemsinconstruction.2PROBLEMAREASThemainproblemareasare•erectinganddismantlingscaffolds•climbingupanddownscaffolds•planksslidingofforbreaking•improperloadingoroverloading•platformsnotfullyplankedor“decked”•platformswithoutguardrails•failuretoinstallallrequiredcomponentssuchasbaseplates,connections,andbraces•movingrollingscaffoldsinthevicinityofoverheadelectricalwires•movingrollingscaffoldswithworkersontheplatform.2.1ErectingandDismantlingFrom15to20%ofscaffold-relatedinjuriesinvolveerectinganddismantling.Themostcommonproblemisthefailuretoprovideanadequateworkingplatformforaworkertousewheninstallingthenextliftofscaffold.Workingfromoneortwoplanksisnotrecommended.Thenextimportantconsiderationinvolvescomponents,suchastie-ins,whichyoushouldinstallastheassemblyprogresses.Failuretodosomakesthescaffoldlessstableand,whileitmaynottopple,itmayswayormoveenoughtoknocksomeoneofftheplatform.Thishappensmoreoftenwhenplatformsareonlyoneortwoplankswideandguardrailsaremissing,asisfrequentlythecaseduringerectionanddismantling.2.2ClimbingUpandDownApproximately15%ofscaffold-relatedinjuriesoccurwhenworkersareclimbingupanddown.Climbingupanddownframesisacommonbutunacceptablepracticethathasresultedinnumerousinjuriesandfatalities.Climbingupanddownbracesisalsoafrequentcauseofaccidents.Youmustprovideadequateladderstoovercomethisproblem.Inaddition,workersmustuseproperclimbingtechniques(three-pointcontact).2.3PlanksSlidingOfforBreakingManyscaffoldinjuriesinvolveproblemswithplanks.Ifscaffoldplanksareuncleatedorotherwiseunsecuredtheyeasilyslideoff–thiscausesasurprisingnumberofinjuries.Scaffoldplankscanalsobreakiftheyareinpoorconditionoroverloaded.Itisthereforeimportanttousepropergradesoflumberandtoinspectplanksbeforeerectiontoensurethattherearenoweakareas,deterioration,orcracks.Anothercommonproblemisinsufficientorexcessiveoverhangofplanksattheirsupport.Excessiveoverhangcancauseaplanktotipupwhenaworkerstandsontheoverhangingportion.Insufficientoverhangisaleadingcauseofplanksslippingoff.2.4ImproperLoadingorOverloadingOverloadingcausesexcessivedeflectioninplanksandcanleadtodeteriorationandbreaking.Overloadingoccursmostofteninthemasonrytradewhereskidsofmaterialcanexceed1500kg(3000lb.).Ifmaterialisleftoverhangingthescaffoldplatformitcancauseanimbalanceleadingtothescaffoldoverturning.2.5PlatformsNotFullyDeckedThissituationisrelatedtoinjuriesnotonlyduringerectionanddismantlingbutingeneralscaffolduse.TheConstructionRegulation(OntarioRegulation213/91)requiresthatallscaffoldplatformsmustbeatleast450mm(18inches)wide.Allplatformsabove2.4metres(8feet)mustbefullydecked.2.6PlatformswithoutGuardrailsPlatformswithoutguardrailsareaserioussafetyprobleminconstruction.Guardrailsareanimportantfallpreventionmeasurenotonlyforhighplatformsbutalsoforlowones.Overone-thirdofthefallsfromscaffoldsarefromplatformslessthan3metres(10feet)inheight.Therefore,guardrailsarerecommendedduringnormaluseforallscaffoldplatformsover1.5metres...
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