JAG 09/3196
Electrical Safety Office QueenslandTelephone 1300 650 662Website www.justice.qld.gov.au
Electrical Safety Code of Practice 2010 Electrical Work
Department of Justice and Attorney-General
Electrical Safety Office Queensland
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Contents
Part 1 : Introduction ................................................................................................. 3
1.1 Application and scope of Code ................................................................................ 3
1.2 Legislative framework ............................................................................................... 3
1.3 What is a code of practice? ...................................................................................... 4
1.4 What is this Code about? .......................................................................................... 5
1.5 This Code includes .................................................................................................... 5
1.6 This Code does not include ....................................................................................... 6
1.7 How is this Code set out? ......................................................................................... 7
1.8 What is ‘electrical work’? .......................................................................................... 7
1.9 Obligations under the Electrical Safety Act 2002 ...................................................... 7
1.10 How can I meet my obligations? .............................................................................. 7
1.11 Defences for failing to meet your electrical safety obligation .................................. 8
1.12 Penalty for failure to meet your electrical safety obligation ..................................... 8
Part 2 : Risk Management .................................................................................... 10
2.1 Risk .......................................................................................................................... 11
2.2 The risk management process ................................................................................ 11
2.3 Common electrical risks ..........................................................................................14
2.3.1 Electrical risks and causes of injury .............................................................................. 14
2.4 Instruction, training and supervision ......................................................................15
2.4.1 Types of training ........................................................................................................... 16
Part 3 : Working De-energised ................................................................................17
3.1 Scope .......................................................................................................................17
3.2 Regulatory requirement ...........................................................................................17
3.3 General ....................................................................................................................17
3.4 Low voltage isolation and access .............................................................................18
3.4.1 Switching, de-energising and re-energising .................................................................. 18
3.4.2 Isolating and disconnecting .......................................................................................... 18
3.4.3 Proving de-energised ................................................................................................... 20
3.4.4 Altering isolation for testing, fault finding and energising ........................................... 22
Part 4 : Working Live .............................................................................................. 23
4.1 Scope ...................................................................................................................... 23
4.2 Regulatory requirement .......................................................................................... 23
4.3 Important issues when working live ....................................................................... 23
4.3.1 Documentation ............................................................................................................ 23
4.3.2 Conductive materials ................................................................................................... 24
4.3.3 Work position .............................................................................................................. 24
4.3.4 Safety observer (electrical) .......................................................................................... 25
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4.3.5 Emergency planning .................................................................................................... 26
4.3.6 Safety barriers and signs ............................................................................................. 27
4.3.7 Personal Protective Equipment (PPE) ............................................................................. 28
4.4 What to use to work safely – tools, instruments and equipment used for electrical work ........................................................................................................................ 28
4.4.1 General ........................................................................................................................ 28
4.4.2 Selection, testing, maintenance of tools, instruments and equipment ........................ 30
4.4.3 Use of instruments and test devices .............................................................................31
4.4.4 Instruments and test devices ........................................................................................31
4.4.5 Ladders, portable pole platforms and scaffolds .......................................................... 32
4.5 Testing and fault finding – providing the work is safe ............................................. 32
4.5.1 General ........................................................................................................................ 32
4.5.2 Ensuring correct connections (including polarity) ........................................................ 33
Appendix A: Meaning of terms used in this Code .................................................. 37
Appendix B: Further information ........................................................................... 59
B.1 Common sources of electrical risks ........................................................................ 59
B.1.1 Identifying sources of electric shock ............................................................................ 59
B.1.2 Tripping of supply on powerlines ................................................................................. 60
B.1.3 Working near sources of arcing, explosion or fires ...................................................... 60
B.1.4 Working in unsafe atmospheres .................................................................................. 62
B.1.5 Isolation and access .................................................................................................... 62
B.2 Other electrical risks to be addressed .................................................................... 65
B.2.1 Working in and around trenches, pits and underground ducts .................................... 65
B.2.2 Working with ladders, scaffolds, portable pole platforms ........................................... 65
B.2.3 Working with elevating work platforms (EWP) ............................................................. 67
B.2.4 Working on or from poles and towers .......................................................................... 75
B.2.5 Tagging out of service .....................................................................................................81
B.2.6 Excavation near energised cables ...................................................................................81
B.2.7 Vegetation management, chainsaws and electrical workers .......................................... 83
B.2.8 Use of tools ................................................................................................................... 83
B.3 General elements of a safe system of work ............................................................. 84
B.4 High voltage isolation and access........................................................................... 84
B.4.1 General ........................................................................................................................ 84
B.4.2 High voltage isolation and access system ................................................................... 85
Appendix C: Exclusion zones for electrical parts ...................................................88
Appendix D: Electrical Safety Act 2002 ..................................................................94
Appendix E: Electrical Safety Regulation 2002 ...................................................... 95
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Part 1 : Introduction
1.1 Application and scope of Code
• ThisElectrical Safety Code of Practice 2010 - Electrical Work(theCode)replacestheCode of Practice - Electrical Work 2002.
• ThisCodewasmadeon18December2009.
• ThisCodecommencedon1January2010.
• ThisCodeexpires10yearsaftertheabovecommencementdate.
1.2 Legislative framework
TheQueenslandElectrical Safety Act 2002(theAct)isdirectedateliminatingthehumancosttoindividuals,familiesandthecommunityofdeath,injuryanddestructionthatcanbecausedbyelectricitynotonlyinworkplaces,butthroughoutthecommunity.
TheActsetsouttheobligationsthatentities,employers,employees,workers,designers,manufacturers,importersandpersonsincontrolofelectricalequipmentmustmeetinordertocomplywiththerequirementsofthelaw.
Thefundamentalprincipleofthelegislationistosetlegalrequirementstoensuretheelectricalsafetyoflicensedelectricalworkers,otherworkers,licensedelectricalcontractors,consumersandthegeneralpublic.
TheWorkplace Health and Safety Act 1995(WHSAct)placesobligationsoncertainpersonstoensurehealthandsafetyintheworkplace.Workplacehealthandsafetyisensuredwhenpersonsarefreefromdeath,injuryorillnessandtheriskofdeath,injuryorillnesscreatedbyworkplaces,relevantworkplaceareas,workactivitiesorplantorsubstancesforuseataworkplace.
Intermsofelectricalsafety,wheretheActandtheWHSActbothapply,theActtakesprecedence.
TheElectrical Safety Regulation 2002(theRegulation)prescribes,amongotherthings,therequirementsforworkingaroundliveelectricalparts.
WhilethisCodegivespracticaladviceonwaystomanageobligationsoftheAct,itdoesnotprovideadviceaboutallelectricalsafetyobligations.FourothercodesofpracticemadeundertheActare:
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• Electrical Safety Code of Practice 2010 - Working Near Exposed Live PartsTheElectrical Safety Code of Practice 2010 - Working Near Exposed Live Partsgivespracticaladviceonwaystomanageelectricalriskwhenworkingnearexposedliveelectricalparts.Thecodeappliestopeoplesuchasplantoperators,painters,peopleerectingorworkingonscaffolds,signmakersandpeopleworkingwithirrigationpipesnearexposedliveelectricalparts.Thepracticalguidanceprovidedinthecodemayberelevanttoelectricalworkerswhentheyareperformingelectricalworknearanotherexposedlivepart.
• Electrical Safety Code of Practice 2010 – Electrical Equipment Rural IndustryTheElectrical Safety Code of Practice 2010–Electrical Equipment Rural Industrygivespracticaladviceonawayofdischargingaperson’selectricalsafetyobligation.Includedinthecodearewaystoidentifyandmanageexposuretorisksofinjuryandpropertydamagecauseddirectlyorindirectlybyelectricity.
• Electrical Safety Code of Practice 2010 - WorksTheElectrical Safety Code of Practice 2010-Worksprovidespracticaladviceforanelectricityentitytomanageelectricalsafetyrisksassociatedwithearthingsystems,undergroundcablesystemsandsupportingstructuresofoverheadlinesformingpartoftheworksofanelectricityentity.
• Electrical Safety Code of Practice 2010 – Risk Management TheElectrical Safety Code of Practice 2010–Risk Managementgivespracticalwaysofmanagingelectricalsafetyrisks.ThecodeclearlydefinesandexplainsthefivestepriskmanagementprocessthatobligationholdersundertheActshouldperformtomakesureallelectricalrisksareminimised.
Referencestolegislation,AustralianStandardsandotherdocumentsinthisCodearecurrentatthetimeofprinting.Fromtimetotime,amendmentsaremadetolegislation.Theusershouldthereforechecktoensureapplicablelegislationiscurrentatthetimeofreading.
1.3 What is a code of practice?
Acodeofpracticeisadocumentmadeundersection44oftheAct.Itgivespracticaladviceonwaystodischargeelectricalsafetyobligations.Includedinacodearewaystoidentifyandmanageexposuretorisksofinjuryandpropertydamagecaused,directlyorindirectly,byelectricity.
Undersection45oftheAct,thecodeofpracticedoesnotstateallthatapersonmustdo,ormustnotdo,todischargetheirelectricalsafetyobligation.
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However,thepersonfailstodischargetheelectricalsafetyobligationifthey:
• contravene,orotherwiseactinconsistentlywith,thecodeofpractice;and
• donotfollowawaythatisaseffectiveas,ormoreeffectivethan,thecodeofpracticefordischargingtheelectricalsafetyobligation.
1.4 What is this Code about?
ThisCodeprovidespracticaladviceandgivesbenchmarksforperformingelectricalworkinwaysthatareelectricallysafe.Itprovidesguidanceonmanagingelectricalriskonly;noguidanceonotherrisksisprovided.ThisCodehasbeendesignedtoreflectthetwowaystoperformelectricalwork:workingde-energisedandworkinglive.
AppendixAcontainsthemeaningoftermsusedinthisCode.
1.5 This Code includes
ThisCodeappliesto:
• electricalworkers;
• employersofelectricalworkersandself-employedelectricalworkers;
• electricalcontractors;and
• personsnotrequiredtoholdanelectricalworklicenceundersection55oftheAct.
ThisCodefocusesonlyontheelectricalaspectsofworkperformedbythefollowingclassesoflicence:
• restrictedelectricalworklicenceholders;
• electricalworktrainingpermitholders;
• licensedelectricallinespersons;
• licensedelectricaljointers;
• licensedelectricalfitters;and
• licensedelectricalmechanics.
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1.6 This Code does not include
• Approvedworkperformedunderahighvoltagelivelinemanagementplan,asprescribedinsection13oftheRegulation,isnotcoveredbythisCode.However,highvoltagelivelineworkersaresubjecttothisCodeforelectricalworkactivitieswhilenotperforminghighvoltagelivelinework.InformationonhighvoltageisolationandaccessiscontainedinAppendixB.4.
• FunctionaloperationssuchasswitchingperformedregularlytooperateelectricalequipmentarenotcoveredbythisCode.However,switchingtoprovideelectricalaccessispartofthisCode.
• PracticalguidanceprovidedintheElectrical Safety Code of Practice 2010–Working Near Exposed Live Partsmayberelevanttoelectricalworkerswhentheyareperformingworkoneitherliveorde-energisedparts.
• Apartfromcorrectconnections(includingpolarity)thisCodedoesnotaddresstheinspectionandtestproceduresdetailedinsection8ofAS/NZS30001.
• ThisCodedoesnotcovergeneralhealthandsafetymatters,suchaspreventingfallsfromheights.TheserequirementscanbesuppliedbytheDepartmentofJusticeandAttorney-General’sWorkplaceHealthandSafetyQueensland.Thisinformationmaybeobtainedonlineatwww.worksafe.qld.gov.au.
• Informationmayalsobefoundfromsourcesincluding:
- SafeWorkAustralia;
- ElectricityNetworksAssociation;
- AustralianRadiationProtectionandNuclearSafetyAgency;and
- StandardsAustralia.
1 Furtherinformationoninspectionandtestingcanbeobtainedfromcodesandstandardsproducedbyothersourcesincluding:Manufacturesandsuppliers,ElectricityNetworksAssociationofAustralia,StandardsAustralia;andotherrelevantindustryassociations.
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1.7 How is this Code set out?
• Parts1and2outlinegeneralinformationabouttheCode,thelegislationandriskmanagement.
• Parts3and4provideguidanceonworkingde-energisedandworkinglive.
• TheappendicescontaindefinitionsandfurtherguidelinesonhowtoperformworkthatiselectricallysafealongwithrelevantpartsoftheActandtheRegulation.
1.8 What is ‘electrical work’?
Thedefinitionofelectricalworkfromsection18oftheActiscontainedinAppendixA:MeaningoftermsusedinthisCode.
1.9 Obligations under the Electrical Safety Act 2002
Sections29to40oftheActimposeobligationsonpersonswhomayaffecttheelectricalsafetyofothersbytheiractsoromissions.
Forexample,anemployerhasanobligationtoensuretheirbusinessorundertakingisconductedinawaythatiselectricallysafe.Thisincludesidentifyingelectricalrisks,assessingtheriskofinjuryorpropertydamagethatmaybeattributedtorisksandtakingnecessaryactionstominimiseexposuretotherisk.
Thefulllistofobligationholdersisincludedinpart2,division2,oftheAct.
1.10 How can I meet my obligations?
Undersections41to45oftheAct,therearethreemethodsoutlinedtoassistyouinmeetingyourelectricalsafetyobligations:througheitherregulations,ministerialnotices,orcodesofpractice.
Whereapplicable,youmustcomplyinthefollowingmannertomeetyourobligations.
• Ifaregulationisidentifiedasprescribingawayofdischargingyourelectricalsafetyobligation,youwillfailtomeetyourobligationifyoucontravenetheregulation.
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• Ifaministerialnoticeprescribesawayofmeetinganelectricalsafetyobligationinrelationtoanelectricalrisk,youwillfailtomeetthatobligationifyoucontravenetheministerialnotice.
• Ifacodeofpracticestatesawayofmeetingyourelectricalsafetyobligation,youwillfailtomeetthatobligationifyou:
- contravenethecodeoractinawayinconsistentwiththecode;and
- donotfollowawaythatisequallyeffectiveto,ormoreeffectivethan,thecodeofpracticefordischargingyourelectricalsafetyobligation.
IfthisCodeisinconsistentwiththeRegulation,thentheRegulationprevailstotheextentoftheinconsistency.
IfthisCodeandtheRegulationareinconsistentwithaministerialnotice,theministerialnoticeprevailstotheextentoftheinconsistency.
YoushouldalsorefertoPart2ofthisCodeonriskmanagementformeetingyourobligationsgenerally.
1.11 Defences for failing to meet your electrical safety obligation
Undersections46and47oftheAct,ifchargedwithabreachofobligation,youcanprovideavaliddefencebyestablishingthattheoffencewasduetocausesbeyondyourcontrol.Inthisinstance,youcannotclaimasadefencethosesectionsoftheCriminalCoderelatingtoanaccidentalactoromission,oramistakenbelief.
Wheretherewasnoregulation,ministerialnoticeorcodeofpracticethattoldyouhowtomeetyourelectricalsafetyobligationunderthecircumstances,youcanseektoestablishthatyouchoseanappropriateway,tookreasonableprecautionsandexercisedproperdiligencetodischargethesafetyobligation.
1.12 Penalty for failure to meet your electrical safety obligation
Undersection27oftheAct,apersononwhomanelectricalsafetyobligationisimposedmustdischargetheobligation.
Maximumpenalty:
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• ifthebreachcausesmultipledeaths:2000penaltyunitsorthreeyearsimprisonment;
• ifthebreachcausesdeathorgrievousbodilyharm:1000penaltyunitsortwoyearsimprisonment;
• ifthebreachcausesbodilyharm:750penaltyunitsoroneyear’simprisonment;or
• otherwise:500penaltyunitsorsixmonthsimprisonment.
ThisCodeshouldbereadinconjunctionwiththeAct,theRegulation,andotherrelevantcodesofpractice.HardcopiesofthesedocumentsareavailablefromtheQueenslandGovernmentBookshopbyphoning(07)38838700or1800801123(outsideBrisbane),orbyvisitingwww.bookshop.qld.gov.au.
FurtherinformationonelectricalsafetyisavailablefromtheDepartmentofJusticeandAttorney-Generalwebsiteatwww.electricalsafety.qld.gov.auorbyphoningtheInfolineon1300650662.
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Part 2 : Risk Management
‘Riskmanagement’isdefinedbytheAustralian/NewZealandStandardAS/NZS ISO 31000:2009 Risk Managementas‘thecoordinatingofactivitiestodirectandcontrolanorganisationwithregardtorisk’.
Theterm‘hazard’isoftenusedasanidentifierofpotentialsourcesofrisk.Howeverinthepracticalapplicationofriskmanagementprinciples,itistheriskitselfthatmustbeaddressed.TheAS/NZS ISO 31000:2009 Risk Management Standard(theStandard)referstotheidentificationofrisk,whilethetermhazardisusedinWorkplaceHealthandSafetyandElectricalSafetylegislationinthesamecontext.Similarly,’riskcontrol’isreferredtointheStandardas‘risktreatment’.Thesedistinctionsaredefinitionalonlyandtheterms‘risk’and’treatment’areusedinthiscodeforthepurposesofclarityandconsistencywiththeStandard.
TheriskmanagementprocessrequiredbytheWHSActissystematicallydividedintofivesteps:
1. identifyhazards(risksundertheStandard),basedonexperience,recordeddataandotherinformation;
2. assessrisksthatmayresultbecauseofthehazards(risks)bymakinganevaluationofthelevelofriskstothehealthandsafetyofworkers,basedontheconsequencesandlikelihoodofharm;
3. decideoncontrolmeasures(risktreatmentmeasuresundertheStandard)fromthehierarchyofcontrol(risktreatmenthierarchy)i.e.eliminate,substitute,isolateorengineerouttherisks,orreducethemthroughadministrativemeasuresorpersonalprotectiveequipmenttopreventorminimisetheleveloftherisks.Thisshouldbeachievedbyselectingthehighestordercontrol(treatment)methodpossibleandthenproceedingdownthelistinorder;
4. implementtheselectedcontrol(treatment)measure(s)intheworkplace;and
5. monitorandreviewtheeffectivenessofthecontrol(treatment)measurestoensurethattheyareworkingcorrectlytocontroltherisksandthatnootherriskshavebeenintroduced.
NOTE:CompliancewiththeriskmanagementprocessdoesnotexcuseapersonfromensuringworkplacehealthandsafetyorfromcomplyingwithanobligationundertheAct.
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Effectiveriskmanagementinvolvesidentifyingalloftherisksintheworkplace,andthencarryingoutariskassessmentforeach,toassessitsseverity,beforedecidingitspriorityfortreatment.Whencarryingoutariskassessment,determinetherisksthathavethegreatestpotentialtocauseharmandagreaterlikelihoodofoccurring.Theserisksarecontrolled(treated)first,followedbythelessseriousrisks.
Attentionshouldbegiventorisksthatmaybeeasytofixbutmayhavelowriskpriorityscores(e.g.powerleadsacrossthefloor).Theserisksshouldbefixedpromptly.Particularattentionshouldbegiventorisksthatmayhaveverylowlikelihoodofcausingharmbutmayresultinmajorconsequences.
TheActrequiresthatelectricalworkandassociatedequipmentbeelectricallysafe(sections29to40);thatis,freefromelectricalrisk.Electricalriskcanbemanagedthroughtheriskmanagementprocessasdescribedbelow.Specificapplicationsoftheriskmanagementprocessarecoveredinrelevantfollowingparts.
In many circumstances, the risks associated with undertaking electrical work near exposed live parts can be equivalent to those associated with live electrical work. Evaluation of the risks and development of risk treatment measures as described in Part 5 of the Electrical Safety Code of Practice 2010 - Risk Management will provide assistance in developing safe work practices.
2.1 Risk
Riskisthelikelihoodandconsequenceofinjuryorharmoccurring.
Forexample,iftheriskiselectricity,therethelikelihoodthataworkermightbeelectrocutedbecauseoftheexposuretoelectricalliveparts.
Thedegreeofriskwilldependontheamountofexposuretotherisk.Withregardtoelectricity,thiswouldrelatetoaspectsoftheelectricityi.e.voltage,frequencyofexposure,anddegreeofrisktreatmentmeasuresinplace.
2.2 The risk management process
Effectiveriskmanagementinvolvesidentifyingalloftherisksintheworkplaceandthencarryingoutariskassessmentforeach,toassesstheseverityofarisk,beforedecidingitspriority.
Whencarryingoutariskassessment,determinetherisksthathavethegreatestpotentialtocauseharmandagreaterlikelihoodofoccurring.Theserisksaretreatedfirst,followedbythelessseriousrisks.
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AssetdownintheElectrical Safety Code of Practice 2010 – Risk Management,therearefivebasicstepsintheriskmanagementprocess:
Step 1 - Identify all risks by:
• observing,inspecting,investigating,communicatingandconsulting;and
• makingarecordoftherisksidentified.
Step 2 - Assess the risks by:
• assessingandprioritisingtherisks;
• dealingwiththehighestpriorityrisksfirst;and
• dealingwithlessrisksorleastsignificantriskslast.
Step 3 - Decide on measures to treat the risks by:
• eliminatingtherisk;
• ifeliminationoftheriskisnotpossible,selecttheserisktreatmentmeasuresinthefollowingorderofpreference:
- substitutione.g.usingmachineswithbetterguardingorusinganinstrumentwithahigherinstallationcategory;
- isolation(notadministrative)e.g.removeorseparatepeoplefromtherisk;
- minimisationbyengineeringe.g.modifyaswitchboardtoreducetheamountofexposedliveparts;
- applicationofadministrativemeasurese.g.usingsigns,trainingorpoliciestotreatrisk;and
- useofpersonalprotectiveequipment(PPE),equipmentorclothingdesignedtoprotecttheworker.
Step 4 - Implement appropriate risk treatment measures that will:
• adequatelytreattherisks;
• notcreateotherrisks;and
• allowworkerstodotheirworkwithoutunduediscomfortordistress.
Step 5 - Monitor the risk treatment measures and review the process:
A: Monitor
• Havethetreatmentmeasuresbeenimplementedasintended?
• Arethetreatmentmeasuresadequate?
• Didtheimplementationoftreatmentmeasurescreateotherrisks?
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B: Review
• Hasanythingchangedovertimesincetheriskprocesswasimplemented?
• Isthetreatmentofrisksstilladequate?
• Wastheriskmanagementprocessconductedeffectively?
Forfurtherinformationonriskmanagementandguidelinesonhowtocompleteariskassessment,pleaserefertotheElectrical Safety Code of Practice 2010-Risk Management.
ThefivestepriskmanagementprocessisillustratedinFigure1.
Step 1 Identify risks
Step 2 Assess and prioritise
risks
Step 3 Decide on risk treatment measures including risk
treatment hierarchy
Step 4 Implement risk
treatment measures
Step 5 Monitor and review Consultation
should be carried out at each step of
this process
Preparation: • Define the context.
• Identify tasks, activities, work processes and practices for assessment
Figure 1: The five step risk management process
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2.3 Common electrical risks
2.3.1 Electrical risks and causes of injury
Thecommonelectricalrisksandcausesofinjurycanbebrokenintothreebroadcategories.Thesecategoriesare:
• Electric shockcausinginjuryordeath.Theelectricshockmaybereceivedbydirectcontact,trackingthroughoracrossamedium,orbyarcing.
• Arcing, explosion or firecausingburns.Theinjuriesareoftensufferedbecausearcingorexplosionorbothoccurwhenhighfaultcurrentsarepresent.
• Toxic gassescausingillnessordeath.Burningandarcingassociatedwithelectricalequipmentcausesarangeofgasesandcontaminantstobepresent.Compoundsrangingfromozonetocyanideandsulphuricacidscanbepresentaswellastheriskssuchaslowoxygencontentintheair.
Thethreecommonelectricalrisksmaybepresentindividuallyorcombined.
Forexample,ifafaultoccurredinthemainswitch-roomofalargeshoppingcentreallthreeoftheelectricalriskscouldbepresent.Thepresenceofstepandtouchpotentialsshouldbeaddressedaswellasthepotentialforanexplosion.Further,burningmaterialssuchasPVCandepoxyresinscancausetheatmospheretobecomehazardous.
Undersection11(2)(a)oftheRegulation,partsthatarenormallyenergisedorthatmaybecomeenergisedunderfaultconditionsmustbetreatedasliveuntilthepartsareprovende-energised.Thecategoriesofcommonelectricalrisks,listedabove,arerelativelyclear.However,aselectricityisnotusuallydetectedbysight,smellorsound,theidentification(orrecognitionofthepotential)oftheriskscanbemoredifficult.RefertoPart2.3ofthisCodeforguidanceregardingtheidentificationofrisksandAppendixBforfurtherinformationonelectricalrisks.
Areas,outsidethescopeofthisCode,thatshouldalsobeaddressedinclude:
• Theflammableatmosphereinbatteryroomsorhazardouslocations.
• Workinginconfinedspaces.
• Electricfieldstrengthandmagneticfieldstrengths.Thesefields,especiallyifthesourceofthefieldisadirectcurrent,cancauseinterferencewithcardiacpacemakersandothermedicallyimplantedelectronicdevices.Precautionsshouldalsobetakentopreventotherriskssuchasflyingmetalobjects.
• Preventingfalls,e.g.whenworkingatheight.
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• Useofexplosivepoweredtools.
• Workingonroadways.
• Theuseofhazardoussubstancessuchaspoisons,chemicals,solvents,syntheticresins,formsofasbestosandpolychlorinatedbiphenyls(PCB).
• Theuseofflammablegasessuchasliquidpetroleum,oxygen,acetyleneetc.
• Theuseofexplosives.
2.4 Instruction, training and supervision
UndertheWorkplace Health and Safety Act 1995,sections28and29,apersonwhoconductsabusinessorundertakingmustprovideinstruction,trainingandsupervisiontopersonstowhomtheyoweanobligation.Section30oftheElectrical Safety Act 2002,whichsetsdowntheobligationofanemployertoensuretheirbusinessorundertakingisconductedinawaythatiselectricallysafe,includesanimpliedrequirementtoprovidetrainingtoensurethattheymeettheirobligation.
Workerswhoarelikelytobeexposedtoelectricalrisksandanyonesupervisingtheseworkersshouldbetrainedandprovidedwithinformationandinstruction.
Trainingshouldbeappropriatetothetypeofworktobeperformed.Insomecases,formaltrainingmayberequired.Inothers,on-the-jobtrainingmaybemoreappropriate.Thespecialneedsofworkersshouldbetakenintoaccountindecidingonthestructure,contentanddeliveryoftraining.Thisassessmentshouldincludeliteracylevels,workexperienceandspecificskillsrequiredforajob.
Adequateandappropriatetrainingisawayofmanagingtherisksassociatedwithelectricalrisks.Thiscanbedoneby:
• determiningwhoneedstobetrained;
• determiningwhattrainingisrequired;
• determininghowtrainingwillbedelivered;
• ensuringthatthetrainingisprovided;
• evaluatingthetraining;and
• keepingtrainingrecords.
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Theamountoftrainingwillbedeterminedby:
• thenatureoftheworkplacerisks;
• thedegreeofassociatedrisk;
• thecomplexityofwork,suchasoperatingproceduresandequipment;
• otherrisktreatmentmeasuresbeingimplemented;and
• thequalificationsandexperienceoftheworker.
2.4.1 Types of training
Therearedifferenttypesofelectricalsafetytrainingthathavedifferentpurposes,including:
• Inductiontraining:forworkerswhencommencingemploymentorwhennewtothejob.Thistrainingisgeneralandmayinvolveaworkplacetour,andinformationaboutconditionsofemployment,administration,organisationalstructure,emergencyproceduresandworkplaceamenities.
• Supervisorandmanagementtraining:providedtohelpensurethatthesupervisionandmanagementoftheelectricalsafetyissuesareappropriatelycarriedoutintheworkplace.
• Specificjobtrainingorfamiliarisationtraining:providinginformationabouttheelectricalandotherrisksassociatedwiththejob.
• Specificelectricalrisktraining:providinginformationabouttherisksassociatedwithworkingnearexposedliveparts.
• Ongoingtrainingorrefreshertraining:providedperiodicallytoensurethatworkcontinuestobeperformedsafely.
• Emergencyprocedurestraining:providedtoensureworkersknowwhattodointheeventofanemergency,includingidentifyingpersonswithspecificemergencyrolesandresponsibilities.
• Firstaidtraining:providedtoensureappropriateproceduresarefollowedforadministeringfirstaid.
• JobspecifictrainingrequiredunderaRegulatione.g.safetyobserverandhighvoltagelivelineworktraining.
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Part 3: Working De-energised
3.1 Scope
Thispartprovidesguidelinesforcreatinganelectricallysafeworkenvironmentbyremovingsourcesofelectricalriskby:
• de-energisinglowvoltage;and
• de-energisingandearthinghighvoltageparts.
Theseguidelinesapplytobothalternatinganddirectcurrentsystems.
3.2 Regulatory requirement
Forregulatoryinformation,refertoAppendixEforalistofrelevantsectionsoftheRegulation.
3.3 General
Anemployerorself-employedpersonshouldensurethataneffectiveprocessofisolationandaccessisusedtoprotectelectricalworkersandothers.Asafesystemofworkshouldbedevelopedwithpeoplewho:
• arerepresentativeoftheelectricalworkers;and
• haveskillsandknowledgeintheareaofwork.
Apersonincontrolofelectricalequipmentshouldmakesurethat,whereisolationandaccessiscomplex,therearesufficientinstructionstoensuretheprocessisperformedsafely.
Instructionsforisolationandaccessshouldbedocumentedwhere:
• complexisolationandaccessistobeperformed;
• isolationandaccessistobeperformedonacomplexelectricalsystem;or
• bothoftheaboveapply.
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3.4 Low voltage isolation and access
3.4.1 Switching, de-energising and re-energising
Assetdowninsection12oftheRegulation,switching,de-energisingandre-energisingmustbeperformedunderasafesystemofworkincludingthepreparationofadocumentedriskassessment.
Switchingincludes,butisnotlimitedto,switchingforisolationorreturntoserviceandsynchronising.Theelectricalsafetyofworkersandothersshouldbeaddressedwhenswitching.
Otherelectricalsafetyconsiderationsthatshouldapplytode-energising,theprocessofde-energisingandre-energisingconnectingpartsfromallsources,include:
• thecapacityofswitchingdevicestomakeandbreakloadcurrents,includingin-rushcurrents;
• thecapacityofswitchingdevicestomakeandbreakfaultcurrents;
• connectingsourcesthatmaynotbesynchronisedorhavethesamephaserelationship;and
• creatingcirculatingcurrentswithinringfeedsofnetworks.
Contingencyactionstobetaken,shouldafaultoccur.Examplesincludewhatformofactionshouldbetakenif:
• themainswitchisacircuitbreakerandthebreakertripstheinstantitisclosed;
• ifathermaloverloadtripsamotor;and
• asafetyswitch(residualcurrentdevice)trips.
3.4.2 Isolating and disconnecting
Isolating
Subjecttosections11and12oftheRegulation,anypartsworkedonmustbeisolatedandprovedde-energisedunlessasafesystemofworkexistsandpermissionhasbeengrantedtoworklive.
Beforeyoucarryoutworkthatisde-energised,youmustensurethatsupplyiseffectivelyisolated.Undersection11(2)oftheRegulation,eachexposedpartistreatedasifitisenergiseduntilitisisolatedandprovednottobeenergised.
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Mattersthatshouldbeaddressedintheisolationprocessinclude:
• de-energisingthepartsfromallsourcesofelectricalpotential;toeffectivelyde-energiseparts,anumberofisolationpointsmayberequired;
• removingrisksfromothersourcesofenergye.g.springtensionorhydraulicpressurewithinmechanisms;and
• finally,conclusivelyprovingthatthepartsarede-energisedsothatelectricshockisnotpossible.
Bothelectricalandnon-electricalworkersshouldclearlyunderstandthemethodorsystemsusedtoisolateandmaintainisolation.Isolationpointsforthejobshouldbeexplainedand,wherepractical,showntoeachoftheworkers.
Awarningorsafetysignshouldbeattachedinaprominentpositiononeachisolationpointordevice.
Isolationcanbeachievedbymethodsorsystemsusinglocksorrenderingthemechanisminoperableoracombinationofthese.Insituationswhereisolationpointsareabletobeaccessedbyotherpeople,itisimportantthattheisolationmethodorsystemisnotabletobeinadvertentlyoreasilycompromised.
Withoutproperauthority,peopleshouldnotalter,removeorchangethestatusofatag,lock,orthemethodusedtorenderthemechanisminoperable.
Disconnecting
Undersection90(3)oftheRegulation,outofservicetagsmustbeusedtoidentifyequipmentormachinerythatisfaultyornotsuitableforuseandhasbeentakenoutofservice.Theelectricalequipmentormachinerymustbeisolatedandtaggedoutofservice.
Outofservicepartsshouldbeleftinasafemanner.Sinceoutofservicetagsapplytoelectricalaswellasnon-electricalpersons,thesafetyofallshouldbeaddressed.
Whereisolationandaccessisrequired,thesafesystemofworkshouldstatewhethertaggingoutofserviceistooccurinadditiontoisolationandaccess.RefertoAppendixB.2.5forfurtherinformation.
Forexample,taggingonthejobofreplacinga45kWmotoronafeedwaterpumpwhilemaintenanceisbeingperformedontheintake‘footvalve’wouldinclude:
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• circuitsforthepumpsupply,startercontrolandcontrolandtelemetrycircuitswouldbeisolatedandprovedde-energised;
• outofservicetagswouldbeplacedinkeylocationse.g.onthestarter;and
• personaltags,locks,methodsofrenderingthemechanisminoperable,oracombinationofthesewouldthenbeinstalled.
3.4.3 Proving de-energised
Undersection11(2)(a)oftheRegulation,exposedpartsmustbeprovedde-energisedbeforeworkbegins.Withintheelectricityindustry,anextensiverangeofdevicescanbeusedtoprovepartsde-energised.Ingeneral,whenprovingde-energised,aworkershouldatleastknow:
• Howtodeterminewhetherthedeviceisfitforpurpose.
• Howtodeterminewhetherthedeviceiswithintest,inspectionorcalibrationdates,asapplicable.
• Howtocorrectlyoperatethedevice,includingselftestfunctions,asapplicable.
• Thetechnicallimitationsofthedevice,testerorequipmentused:
- thethresholdvalueofpick-upforthedevicee.g.forseriestestlampsindicationofvoltages,candependontheoperatorandlightconditions;
- whetherthedevicewilldetectthepresenceofDConACcircuitsandviceversa;
- whetherthedeviceindicatesinductiononacircuit;
- whetheracleanconnectionisrequiredforaccuratereadings;and
- ifthedeviceistobeusedoutdoors,whetherthedeviceiswaterresistantorwaterproof.
• Theactionsrequiredtocompletetheprocessofconfirmingthetesterisoperatingcorrectly,provede-energisedandre-confirmthetester.Theseactionsshouldincludebeingabletodetermine:
- Istheuseofself-testmodepreferredtotestingthedeviceonaknownlivesource?
- Howcanthedevicebeprovenifthereisnoself-testmodeandnoknownsourceofsupply?
- Thesequenceofactionsrequiredtoprovethepartde-energised.
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• Whatisdeemedaconclusivetesti.e.thereisconclusiveproofthatthepartisde-energised.
• Whatisdeemedaninconclusivetestorincorrecttestandwhatactionshouldbetakentoresolvethesituation.
Themethodusedtoprovede-energisedmustbeeffective.Forexample,apanelvoltmetershouldnotbeusedastheonlyindicationthatapartisde-energised.
Proving cables de-energised before work
Whereworkistobeperformedonacable,thecableshouldbede-energised.Ifthecable’sconnectionsareexposed,theconnectionsandattachedlivepartsshouldbeprovedtobede-energisedandidentifiedbeforeworkstarts.
Cutting cables
Particularattentionisdrawntocuttingcables.Bothendsofthecableshouldbecheckedforisolationpriortocutting.
Ensuringthataninsulatedorcoveredcableisde-energisedcanpresentdifficulties.Additionalprecautionsshouldbetakenregardlessofwhetherthecableislowvoltage,highvoltageoracontrolcable.
Forexample,theactionofcuttingamulti-corecontrolcableislikelytocreateariskifsecondarycurrentfromacurrenttransformerispresent.Thisriskmaynotbeinitiallyapparenti.e.thecablecuttersmaynotbedamagedwhenthecableiscut.Ahighvoltagemaydevelopacrosstheopencircuitedsecondarywindingcausinganelectricshock,arcingorafaultatalaterstage.
Dependingonthesituation,alternativeprecautionsmayinclude:
• usingacablespikingorstabbingdevicethatisfitforpurpose;or
• acombinationofprovingde-energisedandphysicallytracingthecable.
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3.4.4 Altering isolation for testing, fault finding and energising
Attimeselectricalworkersneedtoalterisolationtobeabletotestorfaultfind,orboth,onenergisedparts.Typicalexamplesarethetestingperformedbeforereturningequipmenttoserviceandcommissioningnewequipment.
Testing,faultfindingorboth,andthealterationofisolationpointsshouldbeperformedinlinewithasafesystemofwork.Thesafesystemshouldaddressandcontrolexposuretoelectricshockandelectricalexplosion.
Mattersthatshouldbeaddressedwhenisolationpointsarealteredinclude:
• ensuringtheisolationsystemormethodiseffectiveandnotcompromised;
• eliminatingaccesstotheequipmentforallpersonsnotdirectlyinvolvedinthework;and
• contingencyplansifthetestfailsorahazardoussituationisdiscovered.
ReferalsotoPart4.5ofthisCodefordetailsofrisksassociatedwithtestingandfaultfinding.
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Part 4 : Working Live
4.1 Scope
Thispartprovidesguidelinesforsafeelectricalworkpracticeswhencarryingoutlowvoltagelivework,withintherestrictionssetdownbytheRegulation.Thepartcovers:
• importantissueswhenworkinglive;
• theselectionanduseoftools,instrumentsandequipmentforlivework;and
• testingandfaultfinding(thispartincludestheimportanceoftestingtoconfirmcorrectconnections–includingpolaritytest–toensureelectricalsafety).
4.2 Regulatory requirement
Forregulatoryinformation,refertoAppendixEforalistofrelevantsectionsoftheRegulation.
4.3 Important issues when working live
4.3.1 Documentation
Ifitisnotpossibletoworkde-energisedthedecisiontoworklivemustbedocumented.Theoccasionsthatliveworkispermittedisrestrictedbysection12oftheRegulation.Section12oftheRegulationalsohasanumberofrequirementse.g.asafesystemofworkmustexistbeforeworkinglive.Thedevelopmentofasafesystemofworkincludesthepreparationofadocumentedriskmanagementstrategy.Asafesystemofliveworkshouldbedevelopedwithpeoplewho:
• arerepresentativeoftheelectricalworkers;and
• haveskillsandknowledgeintheareaofwork.
RisktreatmentmeasureschosenforliveworkshouldnotrelysolelyonitemssuchasflameretardantorflameresistantclothingandPPE.Appropriatetreatmentmeasurescaninclude:
• isolatingasmanyofthesourcesofelectricpotentialaspossible;thismayinvolveworkinglive,thoughsurroundingpartsneednotbelive;
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• reducingthefaultlevele.g.performingtheworkoutofhourswhenthesupplycanbefedfromonlyonetransformeroragenerator;
• usingasafetyswitch(residualcurrentdevice)e.g.testinganappliance;and
• insituationswhereuninterruptiblepowersupplies,backupgenerators,autore-closing,orautochangeoversystemsareinstalled,thesefacilitiesshouldbedisabled.
4.3.2 Conductive materials
Workerscanbeexposedtotherisksofelectricshock,arcingandexplosionwithoutmakingdirectcontactwithexposedliveparts.Othermaterialscanprovidecurrentpathsfortheelectricshock,faultcurrent,orboth.
Allmaterialsshouldberegardedasconductive,unlessprovedotherwise.Gasesandliquidsshouldberegardedasconductivematerials.
Particularcareshouldbetakenwhenexposedlivepartsarenearearthedsituations.Theelectricshockpathtoearthcanbeviaconductivematerials,suchasconcrete,timberwithahighmoisturecontentorwater.
Metallicpersonalitems,suchaswatchesandwatchbands,shouldnotbewornwhenworkingnearexposedliveparts.Objectsofthiskindcanresultinelectricshocks.Inaddition,burnssustainedneartheseitemscanbeworsebecausetheobjectsretainheatandprovidecontactpointsforcurrenttoflow.
Examplesofothermetalobjectsthatshouldnotbewornwhenperformingelectricalworkinclude:
• neckchains;
• rings;
• bracelets;
• earrings;
• bodypiercings;and
• metalspectacleframes.
4.3.3 Work position
Topreventelectricshock,youshouldworkfromapositionwhereanycontactwithelectricitywouldrequireadeliberatemovementtotouchenergisedpartsorcreateacurrentpath.Adequateworkingclearancetoallowsafeaccessandegressfromtheworkposition,inthecaseofanemergency,shouldbemaintained.
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Examples:
• Choiceofbodypositionshouldbesuchthatifyoumadeaninvoluntaryactionsuchassneezing,youwouldnottouchexposedlivepartse.g.faultfindingonaProgrammableLogicController(PLC)whoseinputsarenexttoliveexposedparts.
• Whenworkinginanawkwardposition–suchastestingcomponentstowardstherearofawashingmachineviathefrontpanele.g.inalaundromat–theworksystem,includingbodyposition,shouldbesuchthatnoelectricshockpathcanbecreated.
• Performingphasesequencingorrotationtestingonoverheadmainsoratanundergroundpillar,theworksystem,includingbodyposition,shouldbesuchthatnoelectricshockpathcanbecreated.
Ifacircuitbreakerhasthefacilitytoberemotelyoperated,thepreferredworkpositionshouldbecommunicatedtoworkers.Forexample,isoperatingacircuitbreakerbystandingattheunitacceptable,or,isitpreferredtouseremotecontrolfacilities?
4.3.4 Safety observer (electrical)
Undersection12(1)(j)oftheRegulation,asafetyobserver(electrical)whoobservestheperformanceoftheliveworkmustbeusedwhenperformingliveelectricalwork,unlesstheworkinvolvestestingelectricalequipmentandadocumentedriskassessmentshowstheworkisnothighrisk.
Whereliveworkisperformed,thefollowingshouldapply:
• Theroleofthesafetyobserver(electrical)shouldbeclearlycommunicatedandunderstood.Theirroleistowarntheworkerorworkersofdangeraswellastoperformrescueandresuscitation,asrequired.
• Asafetyobserver(electrical)shouldhavetheauthoritytostoptheworkbeforetherisksbecometoohigh.
• Thesafetyobserver(electrical)shouldnotcarryoutanyotherworkorfunctionthatcompromisestheirroleasasafetyobserver.
• Thesafetyobserver(electrical)shouldbeabletocommunicateeffectivelywiththeworkerorworkers.Specialistequipmentmaybenecessaryinsituationswherethereisabarriertocommunication.
• Thesafetyobserver(electrical)shouldnothavetoobservemorethanonetaskatatime.
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• Asafetyobserver(electrical)shouldnotbesituatedintheworkbasketoftheelevatingworkplatform.
• Tomeetanelectricalsafetyobligation,asafetyobserver(electrical)shouldnotberegardedasthesolerisktreatmentmeasuretoensureelectricalsafety.
• Thesafetyobserver(electrical)mustbecompetenttohelpwiththeelectricalwork.
• Thesafetyobserver(electrical)mustbecompetentinisolationtechniqueswhereappropriate.
Whenworkingnearexposedliveparts,asafetyobserver(electrical)maybeusedasoneformofrisktreatmentmeasure.
Examples of work near exposed live parts include:
• faultfindingataswitchboardthathasahighprospectivefaultcurrentlevel;
• installingandreplacingcomponentsataswitchboard;
• wheretheworkerisinthe‘safetyobserverzone’i.e.neartheexclusionzoneforexposedliveparts;and
• performingcomplexfaultfinding.
Forfurtherinformationonthefunctionsofasafetyobserver(electrical)whenworkingnearexposedliveparts,pleaserefertotheElectrical Safety Code of Practice 2010 – Working Near Exposed Live Parts.
4.3.5 Emergency planning
Ifapersonsustainsaninjuryduetoelectricalrisks,promptandtimelyactioncansignificantlyreducetheinjury’sseverity.Quickactionmayevensavealife.
Afteranelectricalincident,thereisstillariskofinjurybecauseofthethreecommonelectricalrisks(refertoPart2.3).Itiscrucialtheresponsebeappropriatetoelectricalrisk.Forexample,inalivelowvoltagesituation,rescuemaybeacceptable.However,shouldarescuerequireeitherthevictim,therescuer,orbothtointrudeintoexclusionzonesforexposedlivehighvoltage,isolationandprovingde-energisedshouldbeperformed.
Inaneffectivesafesystemofwork,workersshouldbecompetentatreactingtoelectricalincidentstopreventinjuryorfurtherinjury.Emergencyactionsshouldbetakenthatsuittheworkbeingdone.
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InlinewithAS/NZS 4836 Safe working on low-voltage electrical installations,section9.1,thesafesystemofworkrequiredbeforeliveworkcommencesshouldstipulatethatanypersonreceivinganelectricshockorinvolvedanelectricalincidentshouldreceivemedicalattention.Atrainedmedicalpractitionerisqualifiedtocheckforotherpossibleeffectsofelectricshock.
Processesandproceduresthatshouldbeconsideredinclude:
• Responsetohighvoltageincidentsandinjuries.Thisshouldinclude:
- formsofisolationandaccess;
- rescueandescapefromanEWP;
- cardiopulmonaryresuscitation;and
- firstaidincludingtreatmentofburns.
• Responsetolowvoltageincidentsandinjuries.Theseshouldincluderescueproceduressuchas:
- lowvoltagepolerescue;
- lowvoltageswitchboardrescue;
- confinedspacerescuee.g.rescuefromlowvoltagecablepits;
- rescueandescapefromanEWP;
- cardiopulmonaryresuscitation;and
- firstaidincludingtreatmentofburns.
4.3.6 Safety barriers and signs
PhysicalsafetybarriersandsignscanbeusedtotreatelectricalriskssuchasthosementionedinAppendixB.1.
Barriersandsignsmaybedesigned,erectedorinstalledto:
• protecttheelectricalworkerfrommakingcontactwithliveparts;
• ensurethataccesstoandegressfromtheworklocationofliveworkallowsforclear,unobstructedpassage;and
• warnothersanddirectpeopleawayfromliveparts.
Aphysicalsafetybarriershouldconsistofanon-conductivematerialsuchhaswoodorplasticoralternatively,correctlyearthedsteelandbestrongenoughtowithstandtheimpactfromfallingobjectsorloosematerial.Beforeanybarriersareerected,ariskassessmentmustbecarriedoutbyanappropriatelyqualified
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persontoensuretheappropriatedesignandthatcorrectmaterialsareused.Thebarriermustbeerectedsafely.Thismayentailisolatingtheelectricitysupplywhilethebarrierisinstalled.Abarriermaybetemporaryorpermanentandshouldclearlydesignatethesafeworkareabydefiningtheapproachpathtoapieceofequipment.
4.3.7 Personal Protective Equipment (PPE)
RefertoPart2fortherisktreatmenthierarchy.ThehierarchylistsPPEasthelast–orleastpreferred–option.
PPEshouldbefitforpurposeanditscorrectapplication,use,maintenanceandtestingshouldbeexplainedtousers.
ExamplesofPPEapplicationsinclude:
• Reducingrisksratherthancompoundingriskse.g.ifanexplosionoccursatthighheightthatcausestheenergytoventupwards.Inthissituation,adustcoatoranincorrectlyfittedfaceshieldcouldtraptheexplosionratherthanprotectsomeonefromit.
• Preventionorreductionoftheeffectsofelectricshockandburnsmaybecontrolledby:
- usingclothingthatcoversthearms,legsandbody;theclothingshouldhaveflameresistantorretardantpropertiese.g.cottonorwool,andcontainnometallicthreadsorexposedconductivemateriale.g.ziporrivetsinjeans;
- usingnon-conductivefootwear,suchassteeltoecappedbootsorshoesmanufacturedtoasuitablestandard;and
- usinginsulatinggloves.
4.4 What to use to work safely – tools, instruments and equipment used for electrical work
4.4.1 General
Ingeneralindustry,tools,instrumentsandequipmentthatarepoorlymaintained,inappropriatelyusedornotfitforpurposecancauseinjuries.Withelectricalwork,thereistheaddedriskofelectricshockorlargereleasesofenergyfromarcingandexplosion.
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Thetools,instrumentsandequipmentusedbyelectricalworkersoftenhavespecialdesigncharacteristics.Forexample,manyareinsulatedasarisktreatmentmeasure.However,regularmaintenanceandinspectionarerequired.Otherwise,certaindangerscanarisee.g.theinsulatingmediummightconcealamechanicaldefectthatcouldcauseanopencircuitintheleadofatestingdevice.
Tools,instrumentsandequipment,includethefollowingdevices:
• insulatedhandtoolswheretheinsulationisrelieduponasarisktreatmentmeasure;
• rescueandescapekits;
• portableshortcircuitsandearthdevices;
• operatingrods,includingmeasuringsticks;
• mechanicalequipmentsuchasserialhoistsforlinework;
• cablespikingorstabbingequipment;
• laddersandpoleplatforms;
• insulatingmatsandcovers;
• harnesses,lanyardsandfallrestraintdevices;and
• instrumentsandtestingdevicesusedforprovingde-energised,testingandfaultfinding.
Workersshouldbecompetentinthesafeuseofthedeviceincluding:
• beingabletousethedevicesafelyandinthemannerforwhichitwasintended;
• beingabletodetermine,byinspection,thatthedeviceissafeforusee.g.thedeviceisnotdamagedandisfitforpurpose;
• understandingthelimitationsoftheequipmente.g.whentestingtoproveanACcircuitisde-energised,whetherthedeviceindicatesthepresenceofhazardouslevelsofDC;
• beingawareoftheelectricalsafetyimplicationsforotherswhenthedeviceisbeingusede.g.whetherthedevicecausestheelectricpotentialoftheearthingsystemtorisetoahazardouslevel;and
• knowingwhattodotoensureelectricalsafetywhenaninconclusiveorincorrectresultisobtained.
ReferalsotoAppendixB.2.8forinformationaboutthegeneraluseoftoolsforelectricalwork.
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4.4.2 Selection, testing, maintenance of tools, instruments and equipment
Whenselectingormaintainingtools,instrumentsandequipment,youshouldaddressanumberoffactorstoensureelectricalsafety.Asaminimum,thefollowingissuesaretobeaddressed:
• Thedevicemustbefitforpurpose.
• Equipmentandtestinstrumentsthatcanbevisuallyconfirmedasfunctioningcorrectlyshouldhavevisualconfirmationofcorrectfunctioneachtimebeforeuse.
• Equipmentandtestinstrumentsthatarenotabletobevisuallyconfirmedasfunctioningcorrectlymustbetestedatleasteverysixmonthstoensureproperworkingorder.
• Repairsandmaintenanceshouldmeetappropriatestandardsandmanufacturer’sinstructions.
Appropriateguidanceandstandardsfortesting,inspecting,calibratingandmaintainingthesedevicescanbeobtainedfromsourcesthatinclude:
• manufacturesandsuppliers;
• industrygroups;
• nationalandinternationalcodesandstandardssuchasthoseproducedby:
- StandardsAustraliae.g.ASandAS/NZSpublications;and
- InternationalElectrotechnicalCommissione.g.IECpublications.
Whenselectingdevicesthefollowingshouldbeavoided:
• flameproducingdevices,sinceflameconductselectricity;and
• fireextinguishersthatcontainconductivemediumssuchaswater.
Whenworkingnearexposedlivepartsorworkinglive,thetoolsandequipmentusedshouldbenon-conductiveorinsulated.Examplesinclude:
• torches;
• telescopicdevicese.g.antennas,dentistsmirrors;
• rulersandtapemeasures;
• insulatedtoolse.g.screwdrivers,pliers,cablecutters,spanners,crimpers;and
• electricalorhydraulicpoweredtools.
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4.4.3 Use of instruments and test devices
Whenusinginstrumentsandtestdevices,theworkpracticeshouldinclude:
• Immediatelybeforeandafteruse,thedeviceshouldbeinspectedandfunctionalchecksperformedtoconfirmthatthedeviceisoperatingcorrectly,asappropriate.
• Theworkpracticesemployedduringuseshouldnotonlybesafebutinlinewithdocumentedprocedures.Thesedocumentedproceduresshouldaddressmanufacturer’sinstructions.
4.4.4 Instruments and test devices
Whenselectinginstrumentsandtestdevices,thefollowingshouldbeaddressed:
• Thedevice’sfunction,rangeandclassofaccuracyshouldbeappropriatetobothworkandconditions.
• Toensureelectricalsafety,thecombinationofleadsandinstrumentusedshouldbecapableofwithstandingtheimpulsevoltagesandfaultcurrentlevelsthatcouldbeexperiencedatthelocation.
Therelevantprotectivecategory–orInstallationCategory–ofinstrument,deviceandleadsshouldbechosenasarisktreatmentmeasureforimpulsevoltagesandprospectivefaultcurrents.TheInstallationCategoryisaninherentsafetydesigncriterion.Note:InstallationCategoryisasafetyfocusandisnotassociatedwithinstrumentaccuracy.
Theratingfortestinstrumentsandtestprobesusedon415/240VmainsvoltageequipmentconnectedonthesupplysideofamainswitchboardshouldbeInstallationCategoryIII(3)orIV(4).
TypeAprobes(leads)shouldbeusedformeasuringsupplyvoltages(415/240VAC).
Therefore,workerswhoperformlivetestingorfaultfindinginswitchboardsshoulduseatleastCategoryIII(3)deviceswithTypeAprobes.
Ifthecombinationoftheprobetypeandinstallationcategoryoftheinstrumentisinadequate,alternativemeasuresshouldbetaken.Thesemeasuresinclude:
• obtainingamoresuitableinstrument,deviceandleadcombination;or
• usingotherappropriatemeanstoensureelectricalsafety;fusedleadsorprobesmaybeasuitablerisktreatmentmeasure,buttheyshouldbefitforpurpose.
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Whenselectingavoltageindicatingdevice,considerationshouldbegiventowhetherasingleordoubleprobedeviceismoresuitablee.g.aproximitytesteroramultimeterstyle.
Forexample,aproximitytesterthathasaselftestfacilityandafail-safedesignmaybeappropriatetotesttoprovede-energisedinsomelowvoltagesituations.However,whenmeasuringthevoltageataneutrallink,adoubleprobevoltmeterwithatrailingearthleadismoreappropriate.
4.4.5 Ladders, portable pole platforms and scaffolds
RefertoAppendixB.2.2.
4.5 Testing and fault finding – providing the work is safe
4.5.1 General
Whenfaultfinding,testing,applyingapotentiallyfataltestcurrent,oracombinationofthese,thecommonelectricalrisksarelikelytobepresent(refertoPart2.3).ConsultAppendixB.1forinformationonthesourcesoftheserisks.Totreatrisksofthiskind,asafesystemofliveworkasoutlinedinPart4.3ofthisCodemustbeinplace.
Wherearecognisedtestcannotordoesnotsatisfactorilydeterminethatpartsareelectricallysafe–includingprovingthatallconnectionsarecorrect(includingpolarity)–orwhereanydoubtexists,thefollowingshouldapply:
• Ensuretheelectricalworkoraffectedpartoftheelectricalworkisisolated,disconnected,andmadesafe.
• Makesuretheelectricalworkremainssafelyisolateduntilthematterisresolved.Resolutionmaytaketheformoffurtheradviceandassistancebeingreceivedandactedon.
Toensureelectricalsafety,proceduresforfaultfindingandtestingshouldalsoaddressthefollowing:
• Consideringthecharacteristicsofthetestinstrumenttobeusedandanyresultanteffects,includingtechnicallimitations.Forexample,whenchoosingavoltageindicatingdevicetotestatalowvoltageswitchboard,anappropriateclassofdevicewithanappropriateinternalimpedancewillensureaccurateandvalidtestswhilemaintainingelectricalsafetybynotintroducinghazardouscurrentsandpotentialsintotheearthingsystem.
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• Provingthecorrectoperationofthetestinstrument,bothbeforeandaftereachtest.Ifatestprocedureisinterrupted,thesequenceoftestingandconfirmationshouldberestarted.
• Givingclearinstructiononwhatisseenasaconclusiveteste.g.whatconstitutescorrectconnections(includingpolarity).
• Providingclearinstructiononwhatisregardedasaninconclusivetest.
Iftheprocedureincludesarequirementforinspections,thecriteriafortheinspectionsshouldbeclearlyidentified.
Wheremorethanoneelectricalworkerisinvolvedintheprocessofinstalling,testing,energising,disconnectingandrectifying,anemployerorself-employedpersonshouldensurethatanelectricalworkerisassignedtoensuringelectricalsafetyismaintainedatalltimes.
Anemployerorselfemployedpersonshouldmakesureapersonisclearlyresponsiblefortheoverallintegrityoftheelectricalworkandtesting.
Electricalworkersshouldberegularlytrainedandassessedintheunderpinningknowledgeandpracticalaspectsoftestingacrosstherangeofvariablestheworkerwillencounter.
Clearguidelinesshouldbeprovidedonwhichtestinstruments,orcombinationoftestinstrumentsandequipment,touseincludingaccessoriessuchastrailingearthleads.
4.5.2 Ensuring correct connections (including polarity)
Importance of testing for correct connections (including polarity)
Failuretoensurecorrectconnections(includingpolarity)cancauseseriousincidentsandmayresultinsevereandevenfatalinjuries.Examplesofhazardoussituationsresultingfromincorrectconnections(includingpolarity)include:
• Transposinganactiveandneutral,oranopencircuitneutralconnection,resultinginexposedconductivepartsofaninstallationbecomingenergised.Inthissituation,dangerouspotentialsarecreatedbetweenmetalwork,suchastapsandsinks,andearth.
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• Onthelowvoltagedistributionnetwork,bondingaphasetoearthinsteadofbondingtheneutraltoearth,thuscausingdangerousstepandtouchpotentialsatthebaseofapole.
WhenanactiveandneutralaretransposedinaMultipleEarthedNeutral(MEN)system,theearthedmetalwork–suchastaps–becomelivei.e.thereisasignificantpotentialtoearth.Anerrorofthiskindwillusuallymeanthesupplycannotbeisolatedtoaninstallationviathemainswitch.Inthisinstance,theproblemarisesbecausethemainswitchisintheneutralandatleastoneactiveisnotswitched.
Connectionsmustbetestedtoconfirmthattheyarecorrect.Thetestsmustbeperformedwhenanynewworkisenergised.Thesameappliestoanyalterationsoradditions,orboth.Testingtoprovecorrectconnections(includingpolarity)greatlyreducestheriskofdeathorsevereinjuryassociatedwithincorrectconnections(includingpolarity).
Whereconsumer’smainsareconnectedtoanoverheadservicelineandametallicpin,eyeboltorothersimilarfixtureisrequiredtobeeffectivelyearthedinaccordancewithsection144oftheRegulation,apolaritytestingproceduremustensurethattheearthingofthemetallicpartdoesnotinvalidatethepolaritytest.
Usingthecorrecttestprocedureswillensuretheelectricalworkissafeandwillprotecttheworker,otherworkersandthepublicduringandaftertesting.
Situations when testing correct connections (including polarity) are required
Examplesofwhentestsofcorrectconnections(includingpolarity)arerequiredincludewhen:
• electricalinstallationorrepairworkisconnectedtosupply;
• itemsofelectricalequipment,suchasstovesandhotwatersystems,areconnectedtosupply;
• consumers’mainsorsubmainshavebeenrepairedorreplaced;
• newconsumers’mainsorsubmainsareinstalled;
• lowvoltagebridgesareconnectedorreconnectedonlowvoltagemains;
• connectionstotransformersorgeneratorsaremadeorremade;
• serviceconnectionstostreetlightstandardsaremade,remadeoraltered;
• anewlowvoltageserviceisinstalled;
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• anexistingserviceisdisconnectedorreconnected;or
• adistributionsystemisinitiallyenergisedorwhenanyadditionoralterationtothesystemcouldaffectelectricalsafety.
Procedure for ensuring correct connections (including polarity)
Testproceduresshouldbeproperlydocumentedandeffectivelycommunicatedtotheappropriatepersons.
Theminimumstepsshouldincludeprovingthecorrectelectricalrelationshipexistsbetweenthe:
• active/s;
• neutral;
• earthing,bondingconductorsorboth;and
• independentearthusedfortesting.
Boththesourceofsupplyandtheelectricalworkmayrequiretesting.Forexample,ifathree-phasegeneratoristosupplyaninstallation,thesource–inthisinstance,thegenerator–andtheinstallationrequiretestingbecauseincorrectconnection/smayexistateitherorbothlocations.
Theelectricalworkerresponsibleforensuringcorrectconnections(includingpolarity)mustbecompetentinconfirmingconnectionsarecorrect.Section12(1)(e)oftheRegulationrequiresthatthepersonperformingtheliveworkhastheappropriatetraining.
Precautions when testing for correct connections (including polarity)
Itisnotacceptabletorelyonequipmentfunctionasameansoftestingconnections.Examplesofunacceptabletestmethodsinclude:
• relyingonmotorormeterrotationorbothasareliabletest;or
• assumingthat,becauseaprotectivedevicehasnotoperated,theconnectionsarecorrect.
Withinthetestprocedure,anindicationshouldbegivenastowhatthetestisproving.Theelectricalworkerfollowingtheprocedureshouldbeabletoclearlyidentifyexactlywhatheorsheistestingfor.Forexample,isthetestpurelyapolaritytest,ordoesitincludeothermeasuressuchasprovingthatthereisnoalternativesourceofsupply?
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Installationsshouldnotbeconnectedtode-energisedlowvoltagesources.
Theinstallationearthingsystemshouldnotbeusedforteststoearthunlesstheinsulationbetweentheneutralandearthingsystemhasbeenprovenacceptable.Anindependentearthmaybeused.Theinstallationearthingshouldnotbeusedbecause,asthetestisperformed,thepotentialoftheearthingsystemmayrisetoalevelthatcausesanelectricalrisk.Inthissituation,theimpedanceofthetestingdevicedirectlyaffectsthelevelofpotentialrise.
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Appendix A: Meaning of terms used in this Code
Electrical Safety Act 2002=theActElectrical Safety Regulation 2002=theRegulationElectrical Safety Code of Practice 2010 – Electrical Work =theCodeWorkplace Health and Safety Act 1995=theWHSAct
Access permit or authoritymeansadocumentthatformspartofasafesystemtowork,toprovideelectricallysafeaccesstohighvoltageparts.Atleastonesetofearthsandshortcircuitsmustbeappliedbeforeanaccesspermitorauthorityisissued.Underanaccesspermitorauthority,earthsandshortcircuitsshouldnotberemoved.
Anappliance(seesection13oftheAct)isadevicethatconsumeselectricityatavoltagegreaterthanextralowvoltageandinwhichtheelectricityisconvertedintoheat,motionoranotherformofenergyorissubstantiallychangedinitselectricalcharacter.
Althoughalightfitting,includingitsbulbortube,isanappliance,thebulbortube,takenalone,isnotanappliance.
Associated equipment,(seesection17oftheAct)foranelectricline,meanssomethingordinarilyfoundinassociationwiththeelectricline,especiallyforthepurposeofprotecting,insulatingorsupporting,orsupportingtheoperationof,theelectricline.
Examples of associated equipment:
• abracket,casing,coating,covering,duct,frame,insulator,pillar,pipe,pole,towerortubeenclosing,surroundingorsupportingawireorconductor;or
• anairbreak,circuitbreaker,switch,transformerorotherapparatusconnectedtoawireorconductor.
Authorised person,foranelectricalpart,(seesection59oftheRegulation)meansapersonwho:
(a) hasenoughtechnicalknowledgeandexperiencetodoworkthatinvolvescontactwith,orbeingnearto,theelectricalpart;and
(b) hasbeenapprovedbythepersonincontroloftheelectricalparttodoworkthatinvolvescontactwith,orbeingnearto,theelectricalpart,orisauthorisedtoactforthepersonincontroloftheelectricalpart.
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Cathodic protection systemmeansasystembywhichastructureincontactwithgroundorwaterisprotectedfromelectrolyticcorrosionbyadirectelectriccurrentflowingbetweenthestructureandanelectricalconductorthroughthegroundorwater.
Chief ExecutiveistheDirector-GeneraloftheQueenslandDepartmentofJusticeandAttorney-General.
Competent person(seeschedule9oftheRegulation)meansapersonwhohasacquiredthroughtraining,qualificationsorexperience,theknowledgeandskillstodothetask,forexampletoinspectandtestelectricalequipmentinasafeway,includingknowledgeof:
(i) relevantAustralianStandards;
(ii) relevantcodesofpractice;and
(iii)otherrelevantlegislation.
Construction work(seeschedule9oftheRegulation):
Workis construction workifitis:
(a) worktoerect,construct,extend,alter,convert,fit-out,commission,renovate,repair,refurbish,disassembleordecommissionastructure,orpartofastructure;or
(b) workconnectedwithsitepreparation,excavationandlandscapingforworkmentionedinparagraph(a);or
(c) theassemblyorinstallationofprefabricatedcomponentstoformastructure,orpartofastructure,forworkmentionedinparagraph(a);or
(d) thedisassemblyofprefabricatedcomponentsforworkmentionedinparagraph(a)that,immediatelybeforethedisassembly,formedastructureorpartofastructure;or
(e) anactivitythatisaprescribedactivity.
Workisnot construction worktotheextentitiscarriedoutataworkplace,aspartofabusinessorundertaking,iftheworkistoerectorconstructastructurethat,whenerectedorconstructed,isintendedtobetransportedtoanotherplacee.g.constructionofamanufacturedhomeorprefabricatedbuilding.
Constructionworkistakentostop:
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(a) whentheconstructionworkattheworkplacewheretheconstructionworkisbeingperformedendsandpossessionoftheworkplaceisreturnedtotheclient;or
(b) iftheclientremainsinpossessionoftheworkplacewheretheconstructionworkisbeingperformedwhiletheworkisperformed,whentheconstructionworkattheworkplaceends.
Constructionworkplacemeans:
(i) aworkplacewhereconstructionworkisperformed,iftheconstructionwork:
- isaprescribedactivity;or
- isnotaprescribedactivityandtheestimatedfinalpricefortheconstructionworkismorethan$80,000;or
(ii) aplaceintendedtobecomeaconstructionworkplaceunderparagraph(a)whenworkstartsattheplace.
Cranemeansamachineforraisingorlowering(luffing)aloadandmovingithorizontally(slewing).Itincludesanytypeofcrane,includinganelevatingworkplatform,whetherindependentoranintegralpartofanotherpieceofequipment.Thisdefinitionincludesanagriculturaltractor,oranyotherapparatususedorcapableofbeingusedforraising,lowering,handlingortransportingmaterialsorequipmentinasimilarmanner.Thedefinitionalsoincludesanysupportingstructureandanyotherequipmentancillarytotheuseofthecraneorapparatus,butexcludesanygrabcraneorfloatingcrane.
Amobile cranemeansamachinethat:
(a) isusedprimarilyforraisingorloweringafreelysuspendedload;
(b) iscapableoftravellingoverasupportingsurfacewithouttheneedforfixedrunways(includingrailwaytracks);and
(c) reliesonlyongravityforstability,withnoverticalrestrainingconnectionbetweenitselfandthesupportingsurface,andnohorizontalrestrainingconnection(otherthanfrictionalforcesatsupporting-surfacelevel)thatmayactasanaidtostability.
A tower cranemeansacranewithaboomthatismountedonatowerstructureandincludesself-erectingtowercranes.
Adangerous electrical event(seesection12oftheAct)isanyofthefollowing:
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• Thecomingintoexistenceofcircumstancesinwhichapersonisnotelectricallysafe,if:
- thecircumstancesinvolvehighvoltageelectricalequipment;and
- despitethecomingintoexistenceofthecircumstances,thepersondoesnotreceiveashockorinjury.
• Thecomingintoexistenceofboththefollowingcircumstances:
- ifapersonhadbeenataparticularplaceataparticulartime,thepersonwouldnothavebeenelectricallysafe;and
- thepersonwouldnothavebeenelectricallysafebecauseofcircumstancesinvolvinghighvoltageelectricalequipment.
• Aneventthatinvolveselectricalequipmentandinwhichsignificantpropertydamageiscauseddirectlybyelectricityororiginatesfromelectricity.
• Theperformanceofelectricalworkbyapersonnotauthorisedunderanelectricalworklicencetoperformthework.
• Theperformanceofelectricalworkbyapersonif,asaresultoftheperformanceofthework,apersonorpropertyisnotelectricallysafe.
Examples for the above paragraph:
• theconnectionofelectricalequipmenttoasourceofsupplyinvolvingincorrectpolarityorotherincorrectconnection;
• theperformanceofelectricalworkasaresultofwhichanexposedwireisleftincircumstancesinwhichitcanbeenergisedbytheoperationofaswitchorcircuitbreakerortheinsertionofafuse;
• thediscoverybyalicensedelectricalworkerofelectricalequipmentthathasnotbeenmarkedasrequiredunderthisAct.
De-energisemeanstheprocessofdisconnectinglinesorapparatusfromallsourcesofelectricalenergyusuallybytheprocessofswitching.De-energiseddoesnotmeanisolatedordischarged,orboth.
Direct contact(seesection60oftheRegulation):
(1) Apersonisindirect contactwithanelectricalpartif:
(a) thepersonistouchingtheelectricalpartwiththeperson’sbarehandsoranotherpartoftheperson’sbody;or
(b) thepersonistouchingaconductiveobjectwiththeperson’sbarehandsoranotherpartoftheperson’sbody,andtheconductiveobjectistouchingtheelectricalpart;or
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(c) anarticleofclothingwornbythepersonistouchingtheelectricalpart;or
(d) anarticleofclothingwornbythepersonistouchingaconductiveobject,andtheconductiveobjectistouchingtheelectricalpart.
(2) Operatingplantisindirect contactwithanelectricalpartif:
(a) anypartoftheoperatingplantistouchingtheelectricalpart;or
(b) anythingtheoperatingplantishandlingistouchingtheelectricalpart.
(3) Avehicleisindirect contactwithanelectricalpartif:
(a) anypartofthevehicleistouchingtheelectricalpart;or
(b) anythingbeingcarriedorotherwisehandledbythevehicleistouchingtheelectricalpart..
Dischargedmeansconnectedtothegeneralmassoftheearthinsuchamannerastoremoveanyresidualelectricalenergye.g.applyingearthsandshortcircuitstohighvoltagepartsbeforegainingaccess.
Dischargedalsomeansstoredenergyhasbeenreleasede.g.aclosingspringinacircuitbreaker,hydraulicpressureinasystem,orenergystoredinabattery.
Disconnectedmeansthatthepartsarenotconnectedtoanelectricalsource.Disconnectionmaybeachievedbyde-energising,isolating,separatingorbreakingconnections,orthroughallofthesemethods.Apartthatisdisconnectedmaystillrequiredischargingtoremoveallelectricandotherenergy.
Earthed(seeschedule9oftheRegulation)meansconnectedtothegeneralmassofearth.
Earth moving machinemeansanyitemofplantusedforexcavating,transporting,unloadingcompactingorspreadingearth,overburden,rubble,spoil,pavingmaterial,aggregateorsimilarmaterial.Thetermincludesbackhoesandbulldozers.
Earths, portable earthing devices(PED),refertoearthsandshortcircuits.
Earths and short circuitsmeansportableearthingdevices,earths,earthswitchesetc.Theuseofearthsandshortcircuitsshouldbepartofasafesystemofworkonhighvoltageparts.Who,whenandwhytheearthsandshortcircuitsareapplieddetermineswhethertheyaredesignatedasoperatororworkingearthsandshortcircuits.
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Earthingandshort-circuitingformonepartofasystemtocreateanelectricallysafeenvironment.Thepurposeofearthingandshort-circuitingis:
• tosafelydischargeinducedorresidualvoltage;
• intheeventthatthecircuitbecomesenergized,tocausetheoperationofprotectionequipmenttotripthesupply;and
• tolimittheriseinpotentialdifferenceattheworkarea.
Electrical equipment(seesection14oftheAct)isanyapparatus,appliance,cable,conductor,fitting,insulator,material,meterorwire:
• usedforcontrolling,generating,supplying,transformingortransmittingelectricityatavoltagegreaterthanextralowvoltage;or
• operatedbyelectricityatavoltagegreaterthanextralowvoltage;or
• operatedbyelectricityofanextralowvoltage,iftheequipmentformspartofanelectricalinstallationlocatedinahazardousarea;or
• thatis,orthatformspartof,acathodicprotectionsystem.
However,’electricalequipment’doesnotincludeanyapparatus,appliance,cable,conductor,fitting,insulator,material,meterorwireformingpartofavehicleif:
• itformspartofaunitofthevehiclethatprovidespropulsionforthevehicle;or
• itssourceofelectricityisaunitofthevehiclethatprovidespropulsionforthevehicle.
Examplesofthingsthatarenotelectricalequipment:
• theheadlightsofavehicle;
• ignitionsparkplugsofamotorvehicle;
• theinteriorlightingsystemofavehicle,ifpoweredfromabatterychargedbytheenginethatdrivesthevehicleorbythevehicle’smovement.
Examplesofthingsthatarenotpreventedfrombeingelectricalequipment:
• interiorlightingorasocketoutletinacaravan,ifthelightingoroutletisoperatedbyalowvoltagegeneratingsetorconnectedtolowvoltagesupply;or
• arefrigerationunitinafooddeliveryvehicleoperatingatlowvoltagefromasourceseparatefromthepropulsionunitforthevehicle.
Referalsotosection69oftheRegulationforfurtherinformationonelectricmotorsformingpartofvehicles.
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Electrical equipment work(seesection19(3)oftheAct)iselectricalworkotherthanelectricalinstallationworkorelectriclinework.
Examples of electrical equipment work:
• repairingsubstationelectricalequipment;
• repairinganelectricrange,whetherornotitispartofanelectricalinstallation;or
• installing,jointingorterminatingcoveredcables.
Electrical installation(seesection15oftheAct):
(1) An electrical installationisagroupofitemsofelectricalequipment.
(2) However,agroupofitemsofelectricalequipmentisanelectricalinstallationonlyif:
(a) alltheitemsarepermanentlyelectricallyconnectedtogether;
(b) theitemsdonotincludeitemsthatareworksofanelectricityentity;and
(c) electricitycanbesuppliedtothegroupfromtheworksofanelectricityentityorfromageneratingsource.
(3) Anitemofelectricalequipmentcanbepartofmorethanoneelectricalinstallation.
(4) Forsubsection2(a):
• anitemofelectricalequipmentconnectedtoelectricitybyaplugandsocketoutletisnotpermanentlyelectricallyconnected;and
• connectionachievedthroughusingworksofanentitymustnotbetakenintoconsiderationfordecidingwhetheritemsofelectricalequipmentareelectricallyconnected.
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Examples of an electrical installation:
• Theswitchboard,wiring,lighting,socketoutletsandotherelectricalequipmentpermanentlyconnectedforashopinashoppingcentre.
• Theswitchboard,wiring,lighting,socketoutletsandotherelectricalequipmentpermanentlyconnectedforahouseorresidentialunit.
• Theswitchboard,wiring,lighting,socketoutletsandotherelectricalequipmentpermanentlyconnectedforashoppingcentre.Theelectricalinstallationfortheshoppingcentregenerallyincludestheelectricalinstallationsfortheindividualshops.
• Theswitchboard,wiring,lighting,socketoutletsandotherelectricalequipmentpermanentlyconnectedforaresidentialunitcomplex.Theelectricalinstallationfortheresidentialunitcomplexgenerallyincludestheelectricalinstallationsfortheindividualresidentialunits.
• Theswitchboard,wiring,lighting,socketoutletsandotherelectricalequipmentpermanentlyconnectedwithinacaravan.
Anelectric line(seesection16oftheAct)isawireorconductororassociatedequipmentusedfortransmitting,transforming,orsupplyingelectricityatavoltagegreaterthanextralowvoltage.
However,an’electricline’doesnotinclude:
• awireorconductordirectlyusedinconvertingelectricityintoanotherformofenergy;or
• awireorconductorwithintheinternalstructureofabuilding.
Examplesofthingsthatarenotelectriclines:
• acordforconnectinganairconditioningunit,computer,lamp,televisionortoastertoasupplyofelectricity;or
• apowerorlightingcircuitwithinabuilding.
Electric line work(seesection19(2)oftheAct)iselectricalworkassociatedwithanelectricline.
Examples of electric line work:
• erectinganaerialconductorthatispartoftheworksofanelectricityentityorofanelectricalinstallation;
• installingormaintainingstreetlightingcircuits;or
• testinganoverheadelectricallinetoensureitiscorrectlyconnected.
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Electrical part(seesection59oftheRegulation)means:
• anexposedpart;or
• anoverheadinsulatedelectricline.
Electrical placemeansalocationwhereanelectricalinstallation,electricalequipment,worksofanelectricityentityoracathodicprotectionsystemislocated,includingapremises,place,landorwater.
Electrical risk(seesection10(1)oftheAct)means:
• inrelationtoaperson,therisktothepersonofdeath,shockorinjurycauseddirectlybyelectricityororiginatingfromelectricity;or
• inrelationtoproperty,therisktothepropertyof:
- damagecausedbyacathodicprotectionsystem;or
- lossordamagecauseddirectlybyelectricityororiginatingfromelectricity.
Electrically safe(seesection10(2)oftheAct)means:
• forapersonorproperty,thatthepersonorpropertyisfreefromelectricalrisk;and
• forelectricalequipmentoranelectricalinstallation,thatallpersonsandpropertyarefreefromelectricalriskfromtheequipmentorinstallation;
• forthewayelectricalequipment,anelectricalinstallationortheworksofanelectricityentityareoperatedorused,thatallpersonsandpropertyarefreefromelectricalriskfromtheoperationoruseoftheequipment,installationorworks;
• forthewayelectricalworkisperformed,thatallpersonsarefreefromelectricalriskfromtheperformanceofthework;
• forthewayabusinessorundertakingisconducted,thatallpersonsarefreefromelectricalriskfromtheconductofthebusinessorundertaking;and
• forthewayelectricalequipmentoranelectricalinstallationisinstalledorrepaired,thatallpersonsarefreefromelectricalriskfromtheinstallingorrepairingoftheequipmentorinstallation.
Electrical safety(seesection10(3)oftheAct),forapersonorproperty,meansthepersonorpropertyiselectricallysafe.
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Electrical safety notification(seesection206oftheAct).Thechiefexecutivemayissueanotification(electrical safety notification)that:
• isdirectedatdesigners,manufacturers,importersorsuppliersgenerally,oratstateddesigners,manufacturers,importersorsuppliers;and
• statesrequirementsabouttheuseorsupplyofstatedelectricalequipment,orastatedtypeofelectricalequipmentincluding,ifappropriate,requirementsaboutpreventingtheuseorsupplyoftheelectricalequipmentortypeofelectricalequipment.
Electrical work(seesection18oftheAct)isthemanufacturing,constructing,installing,testing,maintaining,repairing,altering,removing,orreplacingofelectricalequipment.
Examples of electrical work:
• installinglowvoltageelectricalwiringinabuilding;
• installingelectricalequipmentintoaninstallationcouplerorinterconnecter;
• replacingalowvoltageelectricalcomponentofawashingmachine;and
• maintaininganelectricityentity’soverheaddistributionsystem.
However,thefollowingarenot‘electricalwork’:
(a) Installingorremovingelectricalequipmentbyconnectingittoelectricity,ordisconnectingitfromelectricity,byaplugandsocketoutlet.
(b) Repairingorreplacingnon-electricalcomponentsofelectricalequipment.
Examples for paragraph (b):
• repairinghydrauliccomponentsattachedtoanelectricmotor;and
• replacingadrivebeltonawashingmachine.
(c) Replacingacomponentformingpartofelectricalequipmentiftheelectricalequipmenthasbeendesignedsothatthecomponentisreadilyandsafelyabletobereplacedbyapersonwithoutelectricalknowledgeorskill.
Examples for paragraph (c):
• replacingafuse;and
• replacingthebulbinalightfitting.
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(d) Assembling,making,modifyingorrepairingelectricalequipmentinaworkplaceregisteredundertheWHSAct,thatisprescribedunderaregulationforthisparagraph,ifthatistheprincipalmanufacturingprocessattheworkplace,andarrangementsareinplace,andaredetailedinwrittenform,forensuringthat:
(i) theworkisdonesafelyandcompetently;and
(ii) theequipmentistestedtoensurecompliancewithrelevantstandards.
(e) Building,underthesupervisionofanelectricityentity,anoverheadelectriclineonstructuresthatdonotalreadycarryanenergisedoverheadelectricline.
(f) Buildingorrepairingducts,conduitsortroughs(channels)whereelectricalwiringwillbeorisinstalled,if:
(i) thechannelsarenotintendedtobeearthed;
(ii) wiringinstalledinthechannelsisnotenergised;and
(iii)theworkisdoneunderthesupervisionofapersonlicensedtoperformelectricalinstallationwork.
(g) Laying,cuttingorsealingundergroundcablesthatarepartoftheworksofanelectricityentitybeforetheinitialconnectionofthecablestoanelectricitysource.
(h) Recoveringundergroundcablesthatarepartoftheworksofanelectricityentityafterdisconnectionfromanelectricitysource.
(i) Altering,repairing,maintainingorrecoveringanoverheadelectriclinethatispartoftheworksofanelectricityentity,iftheworkisperformedundertheentity’ssupervisionand:
(i) ifthelineisnotonsupportssupportinganotherelectricline-thelinehasbeenisolatedfromanelectricitysourcesothattheclosureofaswitchcannotenergisethesectionofthelinewhereworkisbeingdone;or
(ii) ifthelineisonsupportssupportinganotherelectricline-bothlineshavebeenisolatedfromanelectricitysourcesothattheclosureofaswitchcannotenergisethesectionofthelinewheretheworkisbeingdoneoranadjacentsectionoftheotherline.
(j) Erectingstructuresforthesupportofelectricalequipment.
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Example of structures:
• electricpolesandtowers.
(k) Locating,mountingorfixinginplaceelectricalequipment,otherthan:
(i) makingorterminatingelectricalconnectionstotheequipment;or
(ii) installingsupplyconductorsthatwillconnecttheequipmenttoasupplyofelectricity.
(l) Assistingalicensedelectricalworkertoperformworkonelectricalequipmentunderthedirectsupervisionoftheelectricalworker,ifperformingtheworkdoesnotinvolvethepersondirectlycontactingliveelectricalequipment.
(m) Maintainingthestructuralpartsoftheelectricaltractionsystemonarailway,otherthanoverheadelectriclines,thatformspartoftheworksofanelectricalentity,iftheworkisstructuralworkperformedunderasafesystemofwork.
(n) Workperformedbyapersononelectricalequipmentif:
(i) theelectricalequipmentisnotenergised;
(ii) theworkisprescribedunderaregulationforthisparagraph;and
(iii)itisnecessaryforthepersontoperformtheworktomeettheeligibilityrequirementsforanelectricalworklicence.
Elevating work platformmeansatelescopingdevice,scissordevice,orarticulatingdeviceoranycombinationofthosedevicesusedtomoveandpositionpersonnel,equipmentandmaterialstoandfrom,oratworklocationsaboveorbelowthesupportsurface.
Energise(seeschedule2oftheAct)meansenergisebyelectricity.
Exclusion zone(seesection61oftheRegulation):
(1) Theexclusionzone,forapersonforanelectricalpart,orforoperatingplantoravehicleforanelectricalpart,meansthedistancefromthepartstatedfortheperson,plantorvehicleinAppendixC.
(2) ForapplyingAppendixCtoaperson,thepersonincludesanyarticleofclothingwornbytheperson,andanyconductiveobjectthepersonishandling.
(3) ForapplyingAppendixCtooperatingplant,theoperatingplantincludesanythingtheoperatingplantishandlingotherthan:
(a) aperson;or
(b) ahandheldobjectthepersonishandling.
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(4) ForapplyingAppendixCtoavehicle,thevehicleincludesanythingthevehicleiscarryingorotherwisehandling.
(4A) Despitesubsections(2)to(4),theperson,operatingplantorvehicledoesnotincludeanobject,forexample,atool,thataloneorwithanotherobjectorobjectsisanextensionfromtheperson,operatingplantorvehicleiftheobject:
(a) isaninsulateddevice;and
(b) thedevicehasbeentestedandfoundtobesafeforuseonandneartheelectricalpart.
(5) ForapplyingAppendixCtooperatingplantoperatedbyanauthorisedpersonorinstructedpersonwhodoesnothaveasafetyobserveroranothersafesystemasrequiredundertheschedule,theauthorisedpersonorinstructedpersonmustbetakentobeanuntrainedperson.
(6) However,theexclusionzone,foranelectricalpart,foroperatingplantoperatedbyanauthorisedpersonorinstructedpersonfortheelectricalpart,istakentobethesameastheexclusionzoneforanauthorisedpersonorinstructedpersonfortheelectricalpartif:
(a) theoperatingplantisfittedwithadevicecapableofstoppingtheoperationoftheoperatingplantimmediatelytheoperatingplantisattheexclusionzoneforanauthorisedpersonorinstructedpersonfortheelectricalpart;
(b) thereisinplaceasafesystemofworkfortheuseoftheoperatingplant;
(c) thesafesystemofworkhasbeendevelopedinconsultationwithpersonswhoarebroadlyrepresentativeofindustrialorganisationsofemployeeswhosememberscommonlyoperateoperatingplantoftheoperatingplant’stype;and
(d) withoutlimitingparagraph(b),thesafesystemofworkensuresthedevicementionedinparagraph(a):
(i) isoperatingproperly;and
(ii) issetforatleastthecorrectexclusionzonedistance.
(7) AreferenceinAppendixCtoavehicledoesnotincludeareferenceto:
(a) anaircraft;or
(b) avehiclethatisoperatingplant.
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Examples for paragraph (b):
• TiptrucktippingaloadwouldnotbeavehicleforAppendixC.
• HoweveratiptrucktravellingbetweensiteswouldbeavehicleinAppendixC.
• AvehiclethatincludesanelevatedworkplatformbeingusedforclearingvegetationwouldnotbeavehicleforAppendixC.However,whentheplatformisnotbeingusedforclearingvegetation,thevehiclewouldbeavehicleforAppendixC.
(8) ForapplyingAppendixCtooperatingplant,areferenceto‘anothersafesystem’isareferencetoasystemofworkthat:
(a) hasbeendevelopedinconsultationwithpersonswhoarebroadlyrepresentativeofindustrialorganisationsofemployeeswhosememberscommonlyoperateoperatingplantoftheoperatingplant’stype;and
(b) provides,forpersonsandproperty,thesamelevelofelectricalsafetyas,oragreaterlevelofelectricalsafetythan,thelevelofelectricalsafetyprovidedwithasafetyobserver.
Extra low voltage(seeschedule2oftheAct)meansvoltageof50VorlessACRMS,or120Vorlessripple-freeDC.
Ferro-resonancecanbedescribedasavoltagemultiplicationcircuitonapowersystem.Thephenomenoncauseshigherthannormalsystemvoltagesonthehighandlowvoltagesystems,e.g.700voltsphasetophaseonthelowvoltagesystem.Ferro-resonanceoccurswhenamodestsizedcapacitanceiseitherinseriesorinparallel,withnon-linearinductance,suchasanironcoredtransformer.
Inpowersystems,ferro-resonanceismostcommonlyfoundinthefollowingconditions:
• athree-phasedistributiontransformerisenergisedviaanundergroundcableofmoderatelength;
• thereiseithernoload,orverylightloadonthetransformer;and
• acombinationofthecapacitanceandinductanceexists,andsingle-phaseswitchingoccurse.g.operationofahighvoltagefuseorasynchronousoperationofsingle-phasehighvoltageswitchingdevices,suchasadropoutfuseunitorsomeringmainunits.
Free from electrical risk(seesection10(4)oftheAct),forapersonorproperty,meansthattheelectricalrisktothepersonorpropertyisaslowasreasonablyachievable,havingregardto:
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• likelihoodofharm;and
• likelyseverityofharm.
Hand excavationmeansusingtoolssuchasshovels,picks,mattocks,crowbars.Handexcavationdoesnotincludetheuseofequipmentsuchasjackhammers.Evenwhenhandexcavatingcautionmustbeexercisedwhenworkingclosetolivecables.
Handling(seesection59oftheRegulation)includesanyofthefollowing:
(a)carrying;
(b)connectedto,whetherornottemporarily;
(c)controlling;
(d)holding;or
(e)lifting.
High voltage(seeschedule2oftheAct)meansvoltagegreaterthanlowvoltage.
Include:Wheretheword’include’isusedinthisCode,itshouldbeinterpretedasmeaning’includes,butisnotlimitedto’.
Installation Category (instruments)meansthefaultlevelandvoltageimpulselevelthattheinstrumentisdesignedtowithstand.(RefertointernationalstandardsIEC61010-1andIEC61010-2-031forfurtherinformation.)TheapplicableInstallationCategoriesareoutlinedbelow:
• Installation Category Irelatestosignallevel,specialequipmentorpartsofequipment,telecommunications,electronicandsimilarequipment.Impulsewithstandvoltage:1500V.
• Installation Category IIrelatestothelocallevel,appliances,equipmentsubcircuits,portableequipmentetc.Impulsewithstandvoltage:2500V.
• Installation Category IIIrelatestothedistributionlevel,mainswitchboardsetc.Impulsewithstandvoltage:4000V.
• Installation Category IVrelatestotheprimarysupplylevel,overheadlines,cablesystemsetcfixedinstallation.
Instructed person(seesection59oftheRegulation)foranelectricalpartmeansapersonwhoisactingunderthesupervisionofanauthorisedpersonfortheelectricalpart.
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Isolatedmeansdisconnectedfromallpossiblesourcesofsupplyandrenderedincapableofbeingmadelivewithoutpremeditatedanddeliberateoperation.Undersection20(2)oftheRegulation,asuitablewarningsafetysignmustbeattached.
Examplesofhowisolationcanbeachievedisbyopeningisolators,rackingoutcircuitbreakers,removingfusesorlinks,inhibitingtheoperationofamechanismbylocking,oracombinationofthesemeasures.Isolationinvolvestheuseofsuitablewarningorsafetysignsandinvolveslocks,renderingmechanismsinoperativeoracombinationofthese.
Isolation and accessmeanstheprocessoffullyorpartly,switching,de-energising,isolating,provingde-energised,applyingearthsandshortcircuits,discharging,installingotherprecautions,theissuingofpermitsorauthoritiesandthereversalofthisprocess.Isolationandaccessshouldbepartofsafesystemofwork.
Thetermappliesto:
• theoperationofhighvoltage,lowvoltageandassociatedcircuitse.g.secondarycircuits;and
• alternatingcurrent,directcurrentorboth..
Isolation pointmeansthepoint,oroneofmanypoints,usedtoisolateelectricalparts.
Live (Alive, Energised)meansconnectedtoasourceofelectricalsupplyorsubjecttohazardousinducedorcapacitivevoltages.Generally,‘live’referstoaconductororconductivepartintendedtobeenergisedinnormaluse,includinganeutralconductorandconductivepartsconnectedtoaneutralconductor.
UndertheMENsystemlivedoesnotapplytothefollowing:
• Earthingconductors.
• Theneutralconductorofalowvoltagedistributionnetworkthatisearthedinaccordancewithsection129oftheRegulation.
• TheMENconnectionandtheneutralbarorlinkwhichtheMENconnectionismade.
• ThesheathofaMineralInsulatedMetalSheathed(MIMS)cableandassociatedconductivefittingsusedasacombinedneutralandprotectiveearthingconductorfittingsusedasacombinedneutralandprotectiveearthingconductorinanEarthSheathReturn(ESR)system.
• ConductivesupportsandenclosuresassociatedwithunprotectedconsumersmainsthatareearthedinaccordancewithAS/NZS3000.
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Live work(seeschedule9oftheRegulation)meanselectricalworkperformedincircumstancesinwhichthepartoftheelectricalequipmentthesubjectoftheelectricalworkisenergised.
Low voltage(seeschedule2oftheAct)meansvoltagegreaterthanextralowvoltage,butnotmorethan1000VACRMSor1500Vripple-freeDC.
MustWheretheword‘must’isusedinthisCode,itreflectsthefactthatamandatoryrequirementexistsintheActorRegulation.
Neutralmeanstheconductorofathree-wireormulti-wiresystem,whichismaintainedatanintermediateandapproximatelyuniformpotentialinrespectoftheactiveorouterconductors,ortheconductorofatwo-wiresystemthatisearthedatitsorigin.Aneutralshouldbeconsidered(andtreated)asaliveconductor.
Operating plant(seesection59oftheRegulation)meansplantbeingoperatedforitsintendedpurposeunlesstheoperationoftheplantcannotmateriallyaffectthedistancebetweentheplantandanyelectricalpartinrelationtowhichthereisanexclusionzoneunderthispart.
Examples of operating plant:
• atiptrucktippingaload;
• afixedcraneoperatingatabuildingsite;
• avehiclethatincludesanelevatedworkplatformbeingusedforclearingvegetationfromaroundoverheadelectriclines;
• aconcretepumpingtruckpumpingconcrete;and
• aharvesterwithheightchangeableattachmentsbeingusedtotransfergraintoatruck.
Exampleofplantthatisnotoperatingplant:
• afurnitureremovalvanunderanelectriclineraisingorloweringtheelectricallyorhydraulicallyoperatedplatformlocatedattherearofthevan,ifneithertheplatformnoranythingontheplatformrisesabovetheroofofthevan.
Penalty units:pleaserefertosection5ofthePenalties and Sentences Act 1992.
Permit or authoritymeansanaccessoratestpermitorauthority.
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Plantincludesanymachinery,equipmentandappliance,andanyarticledesignedforuseasacomponentin,orasanaccessoryto,anymachinery,equipmentorapplianceandincludesearthmovingmachinesandhoists.
Potentially fatal test currentmeanscurrentusedaspartofatestwherethecurrentisgreaterthanorequalto10mAACor300mADC,orboth.Thesevaluesarebasedonthemaximumvalueofcurrentatwhichapersoncanletgoor’thresholdofletgo’,describedinAS60479Effects of current on human beings and livestock.
Thethresholdofletgoshouldbeconsideredthemaximumvalueofcurrenttoflowthroughthehumanbodybeforeasignificantriskofventricularfibrillationexists.Therefore,iftestsusecurrentsabovethepotentiallylethaltestcurrent,considerationshouldbegiventotheimplementationofeffectiverisktreatmentmeasures.
Principal contractorforconstructionworkisthepersonappointedbytheclientastheprincipalcontractorfortheconstruction.Ifthereisnoclientfortheconstructionwork,thepersonwhocommissionstheconstructionworkistakentobetheprincipalcontractorfortheconstructionwork(WHSAct,section13).
Aqualified technical person(seesections7(2)to7(4)oftheRegulation),foranindividual,partnershiporcorporation,isanindividualwhosatisfiesthechiefexecutivethatheorshe:
(a) isafitandproperperson;and
(b) either:
(i) iftheelectricalworktobeperformedbythelicensedelectricalcontractormaybeperformedonlybytheholderofanelectricalworklicence--hasheldforatleastayear,orashorterperiodconsideredacceptablebythechiefexecutive,andstillholds,anelectricalworklicence;or
(ii) hasheldforatleastayear,orashorterperiodconsideredacceptablebythechiefexecutive,andstillholds,anexternalcontractingauthority;and
(c) iscompetenttoperformelectricalworkas,orfor,alicensedelectricalcontractor;and
(d) hassatisfactorilyfinishedacourseofinstruction,oranexaminationrequiredbythechiefexecutive,ontechnicalaspectsofperformingelectricalwork.
Despitesubsections(1)and(2),forapersonwhoisanindividualtobeaqualifiedbusinesspersonorqualifiedtechnicalperson:
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(a) foranindividualwhoholds,orhasappliedfor,anelectricalcontractorlicence,thepersonmustalsobe,orbeanemployeeof,theindividual;or
(b) forapartnershipthatholds,orhasappliedfor,anelectricalcontractorlicence,thepersonmustalsobeamemberoranemployeeofthepartnership;or
(c) foracorporationthatholds,orhasappliedfor,anelectricalcontractorlicence,thepersonmustalsobeanexecutiveofficer,amemberoranemployeeofthecorporation.
Indecidingwhetherapersonwhoisanindividualisafitandproperperson,thechiefexecutivemayonlyconsider:
(a) thestandardofhonestyandintegritydemonstratedbythepersonincommercialandotheractivitiesinwhichthepersonhasbeeninvolved;and
(b) anyfailurebythepersontoperformcommercialorstatutoryobligationsandthereasonsforthefailure.
Rope test (rope pull test)meansatestperformedonwoodandsteelpoles.Byplacingamechanicalloadasclosetotheheadofthepoleaspractical,viaarope,thetestshouldindicatewhetherthepoleisinherentlysound.
Safe system of work,forliveworkonalowvoltageelectricalinstallation,includes,butisnotlimitedto,asystemofworkthatcomplieswiththeprovisionsofAS/NZS4836Safeworkingonlowvoltageelectricalinstallationsaboutensuringthesafetyofpersonswhileperforminglivework.
Safety observermeansapersonwho:
• observestheperformanceofthework;
• iscompetenttohelpapersonperformingtheelectricalwork;and
• hasbeenassessedinthelastsixmonthstobecompetenttorescueapersonperformingelectricalworkandprovideresuscitation.
Aserious electrical incident(seesection11oftheAct)isanincidentinvolvingelectricalequipmentif,intheincident:
• apersoniskilledbyelectricity;or
• apersonreceivesashockorinjuryfromelectricity,andistreatedfortheshockorinjurybyorunderthesupervisionofadoctor;or
• apersonreceivesashockorinjuryfromelectricityathighvoltage,whetherornotthepersonistreatedfortheshockorinjurybyorunderthesupervisionofadoctor.
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Should:Wheretheword’should’isusedinthisCode,itshouldbeinterpretedasmeaningarequirementwhichneedstobeequalledorexceededsothatanobligationtobedischarged.IfthisCodestatesthatsomethingshouldbedone,therequirementistodowhattheCodesaysordoitinamannerwhichisequalorbetter(electricallysafer)thantheCode.
Step and touch potentialmeansstepvoltageortouchvoltage,orboth.RefertoFigure2.
Figure 2: Examples of step potential and touch potential
Step voltagemeanstheprospectiveoropencircuitvoltagethatmayappearbetweenanytwopoints(onemetreapart)onthesurfaceoftheground.
Supervisionmeanstheoverseeingofworkers,includingtraineesandapprentices,toensureriskstopeopleandpropertyareeliminatedoratleastminimised.Whileasupervisormayperformaudits,auditingshouldnotbeseenasinterchangeablewithsupervision.
Supervisionofelectricalworkincludes:
• healthandsafetymatters;
• statutorycompliancee.g.monitoringtheworkanapprenticeorrestrictedelectricalworkerispermittedtoperform;
• technicalaspectse.g.compliancewithAS/NZS3000;and
• implementationofasafesystemofwork.
Generally,thetwodistinctstylesofsupervisionaredescribedas:
• Direct supervisionmeanssupervisionoccursatalltimesonadirectandconstantbasis.
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• General supervisionmeanssupervisionwheretheworkerdoesnotrequiretheconstantattendanceofthesupervisor.
Switching sheetmeansadocumentthatispartofasafesystemofwork.Eachswitchingsheetshouldhaveauniquereferenceandshouldlistaprocessofisolationandaccessstepbystep.
TheActmeanstheElectrical Safety Act 2002.
TheCodemeanstheElectrical Safety Code of Practice 2010 - Electrical Work.
TheRegulationmeanstheElectrical Safety Regulation 2002.
TheWHS ActmeanstheWorkplace Health and Safety Act 1995.
Tiger tails (Torapoli pipes)areplasticpipetypecablecovers,usedasawarningtovisuallyindicatethepositionofoverheadpowerlinesorstaywires.Tigertailsdonotinsulatewires.
Touch voltagemeanstheprospectiveoropencircuitvoltagethatmayappearbetweenanypointofcontactwithconductiveparts(thatarelocatedwithin2.4metresoftheground)andanypointonthesurfaceofthegroundwithahorizontaldistanceofonemetrefromtheverticalprojectionofthepointofcontactwiththeconductivepart.
Transferred earth potential:Althoughalinemaybe’earthed’,theremaybeadangerousvoltageorpotentialbetweenthelineandtheearthpoint,includingaconcretepoleorasteeltower,attheworksite.
Forexample,wherealineisunderaccessataremotesubstation,afaultnotdirectlyassociatedwiththelineunderaccesscancauseadangerousvoltageriseonthesubstationearthgrid.Thatvoltageriseistransferredthroughthelinetotheworksite,whereitcancreatearisktoworkersonthesite.
Type A probemeansprobessuitableforapplicationtolowvoltageandhighvoltagenonattenuatingnonvoltagedividingprobeassembliesthatareratedfordirectconnectiontovoltagesexceeding33VRMS(rootmeansquare)butnotexceeding63kV.Theseprobeassembliesmaycontainpassivecomponentssuchasfuses.(RefertointernationalstandardsIEC61010-1andIEC61010-2-031forfurtherinformation.)
Untrained person(seesection59oftheRegulation),foranelectricalpart,meansapersonwhoisnotanauthorisedpersonoraninstructedpersonfortheelectricalpart.However,itshouldbenotedfromtheabovedefinitionofexclusionzone,
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thatforapplyingAppendixCtooperatingplantoperatedbyanauthorisedpersonorinstructedpersonwhodoesnothaveasafetyobserveroranothersafesystemasrequiredundertheschedule,theauthorisedpersonorinstructedpersonmustbetakentobeanuntrainedperson.
Please note:undersection61(5)oftheRegulation,forapplyingschedule2oftheRegulationtooperatingplantoperatedbyanauthorisedpersonorinstructedpersonwhodoesnothaveasafetyobserveroranothersafesystemasrequiredundertheschedule,theauthorisedpersonorinstructedpersonmustbetakentobeanuntrainedperson.
Wilfully(seeschedule2oftheAct)means:
• intentionally;or
• recklessly;or
• withgrossnegligence.
Work(seesection59oftheRegulation)meansworkofanytype,whetherornotelectricalwork,otherthanliveworkorelectricalweldingperformedinaccordancewithasafesystemofwork.
Works(seesection25oftheAct),ofanelectricityentity,meanstheelectricalequipment,andelectriclineassociatedequipment,controlledoroperatedbytheentitytogenerate,transform,transmitorsupplyelectricity.
Example of works of an electricity entity:
• anoverheaddistributionsystemofadistributionentity,includingtransformersandswitches.
Example of what is not works of an electricity entity:
• appliancesorfixedwiringinanelectricityentity’sworkshoporoffices.
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Appendix B: Further information
B.1 Common sources of electrical risks
B.1.1 Identifying sources of electric shock
ContactwithelectricpotentialsisoneofthecommonrisksidentifiedinPart2.3fortheelectricalindustry.Theassociatedrisksaresignificant.Inmanagingrisksassociatedelectricalwork,preventingelectricshocksisamajorpartofdischargingelectricalsafetyobligations.Potentialsourcesofelectricshockinclude:
• Voltagesbetweenphasesandbetweenphasesandneutral.
• Voltagesbetweenphases,neutralandearthwherethereismetalwork,dampsituations,personsandotherconductivesurfacesnearby.Theseconductivesurfacesareasourceofpotentialthatcancauseanelectricshock.
Identifyingothersourcesofelectricshockcanbemoredifficult,butthefollowinglistwillhelp.Sourcesinclude:
• Voltagesacrossopenswitchcontactse.g.voltageacrossalightswitchonanincandescentlightingcircuitorthevoltageacrossabustiewhereonesideisde-energised.
• Voltagesacrossundischargedcapacitors.
• Voltagesondisconnectedconductors,particularlyneutrals.
• Voltagescausedbystaticelectricity,leakageordischarge,orlightning.
• Thepotential(voltage)betweenpartsoftheearthinMultipleEarthedNeutral(MEN)systemscanchange,sometimescausingelectricshocks.Thechangingearthpotentialcanbeduetoanumberofcausesincluding:ahighimpedancereturnpathtothelowvoltagedistributionneutral,faultsonotherpartsofthepowersystemorlightningstrikes.
• Inducedvoltagesfromsourcesotherthanthecircuitbeingworkedone.g.nearbycircuitsorradiofrequencytransmitters.
• Voltagesacrossthesecondaryterminalsoftransformers,includingcurrenttransformers.
• Voltagesbetweenparts,oropencircuitedpartsofoneearthsystem,orvoltagesbetweendifferentearthingsystems.
• Incorrectwiringconnectionse.g.transposingactiveandneutral,commonlyreferredtoasincorrectpolarity.
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• Faultyequipmente.g.theframeoffaultyequipmentmaybecomeenergized.
• Voltagesfromsourcesneartheworkbeingperformed.Examplesinclude:
- workingonaremoteareapowersupplywherebothACandDCvoltagesmaybepresent;
- repairinglightsonashopfaciawhenoverheadpowerlinesarenearby;
- workingontransducercircuitswhenotherACandDCcircuitsarepresent;and
- workingonapowersystemwithmultiplecircuitsthatmaybeofmultiplepotentials.
• Voltagesonthecircuitbeingworkedonfromothersourcesincluding:
- illegalconnectionsorreconnections;
- UninterruptiblePowerSupplies(UPS)andbackupsupplies;
- motorgeneratorsoralternators;
- DConACcircuits;
- AConDCcircuits;
- harmonicse.g.3rdharmonic150Hzinneutralsandearthswherethereisalargefluorescentlightloadandswitchmodepowersupplies;and
- backElectroMagneticForces(EMF)fromcollapsingmagneticfieldsorrotatingmachinery.
• Stepandtouchpotentialsandtransferredearthpotentials.Transferredearthpotentialsoftenresultfromsystemfaults.
B.1.2 Tripping of supply on powerlines
Ifcontactismadewithpowerlines,supplywillnotbedisconnectedimmediately.Infact,ifthefaultcurrentislow,thesupplymaynottripatall.
Dependingonthevoltageandtypeofprotection,thereisaninbuiltdelayaslongasanumberofsecondsbeforedisconnectionoccurs.Evenifanoverheadfeederdoestrip,itmayre-closeandenergisethefaultagain.
B.1.3 Working near sources of arcing, explosion or fires
Arcs,explosionsandelectricalfaultscancauseburns.Workersshouldbeprotectedfromtheeffectsofburns.Examplesoftriggersforarc,explosionsandfaultswhichcauseburnsinclude:
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• Materialsprovidingaconductivepathbetweensourcesofpotentiale.g.uninsulatedtoolsfallingacrossbusbars.
• Abnormalconditionsoncircuitssuchas:
- lightningstrikingmains;
- circuitsofdifferentvoltagestouchingeachothere.g.HVcontactingLVcircuits;and
- highvoltageinthesecondarycircuitofacurrenttransformerifanopencircuitoccurswhencurrentisflowingintheprimarycircuit.
• Abnormallyhighvoltageswhensynchronisingdifferentsupplies.Forexample,ifthewaveformsare180ºoutofphase,twicethepeak-to-peakvoltagemaybeimposed.
• Voltagemultiplicationeffectssuchas:
- ferro-resonancewherethecapacitiveandinductivecomponentsofundergroundcablesandtransformerscansignificantlyincreasevoltageswhensingle-phasingoccurs;and
- re-strikecanoccurifcapacitorsareenergised,de-energisedandre-energisedinrapidsuccession.
• Leakageorelectricaldischargecausinginsulationtobecompromisede.g.acombinationofabuildupofcontaminantsoninsulatorsandwetweatherortrackingthroughairvoidsinpitchfilledinsulatingchambers.
• Failureofinsulatingmediums2.
Theconsequencesofarcs,explosionsandelectricalfaultsarecompoundedbyhighfaultcurrents.Thepotentialforinjuryisextremebecauseoftherapidreleaseofelectricalenergy.
Thelevelofelectricalenergyreleasedcanequal20timestheratedsupplycurrent.Whenhighfaultcurrentsarepresent,magneticforcesbetweentheconductorscanbehighenoughtocausetheconductorsupportstomechanicallyfail.Thiscausesadditionaldamage.
Protectionsystemsshouldensurethatthesehighfaultcurrentsonlyflowbriefly.However,whenhighfaultcurrentsarepresent,circuitprotectionmaynotoperatetoprotectapersonfromelectricshock,arcingorexplosions.
2 Therearenumerousinsulatingmediumsinusethatshouldbeconsidered.Someofthemediumsincludepolyvinylchloride(PVC),crosslinkedpolyethylene(XLPE),vulcanisedinsulatingrubber(VIR),air,epoxycompoundsandresins,zellamite,transformeroil,cableoil,vacuum,sulphurhexaflouride,pitchcompounds.
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Duringthetimethatittakestoclearthehighfaultcurrent,thearcsproducedhaveenoughenergytocauseanexplosion,meltmetallicswitchboardcubicles,causesevereburnsandflashburnstothefaceandeyes,aswellasinjuryfromflyingdebrisordislodgedcomponents.
B.1.4 Working in unsafe atmospheres
Afterfaultsandfires,ofteninemergencies,electricalworkersmaybeexposedtounsafeatmospheres.Toxicgasesandlackofoxygencancauseillnessanddeath.Generalworkplacehealthandsafetyrisktreatmentmeasuresshouldbeusedinthesesituations.
Themethodofextinguishingfiresshouldbeaddressed.Typically,carbondioxideorpowdertypedevicesareusedagainstelectricalfires.Extinguisherssuchaswater,foam,andwetchemicalshouldnotbeusedastheysignificantlyincreasetheriskofelectricshock.FurtherinformationcanbeobtainedfromtheQueenslandFireandRescueServiceonlineatwww.fire.qld.gov.au.
B.1.5 Isolation and access
RisksidentifiedinPart2.3shouldbeaddressedinthecontextofisolationandaccess.Risksourcesinvolvingisolationandaccessinclude:
• Correctlyisolatingsupplybutnotdischargingresidualenergye.g.acapacitivechargemaybepresentinpowersupplies,single-phasemotors,orhighpowerfactorfluorescentfittings.
• Insulationandequipmentfailingorpartiallybreakingdown.
• Earthconnectionfailingtostopanelectricshockinearthedconductivepartswhenstepandtouchpotentialsexist.
• Carryingoutthetaskcausesaperson,somethingapersonmaybehandlingorsomethingapersonisincontactwith,tointrudeintominimumsafeapproachdistances.
• Apowersystemconductingfaultcurrentorbeingsubjecttohighinrushcurrents.
• Instructionsormarkingsonthepartsbeinginadequate,incorrectorboth.
• Usingequipmentnotdesignedfororcapableofanoperatione.g.openinga’noload–bustie’underloadconditionsorrelyingonanopencircuitbreakerasanisolationpoint.
• Anotherpersonenergisingcircuitswhileaworkerisworkingonthem,oravehiclehittingapole.
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• Naturalelementssuchaslightningorwindcausingstaticcharges,overheadmainstoclashorahighvoltagecircuittofallontoalowvoltagecircuit.
• Theinter-corecapacitiveeffectsoflongmulti-phasecables.
• Changestowiringnotbeingreflectedindrawingsi.e.thedrawingsarenot’asbuilt’.Anexample:alivecontrolorsupervisioncircuitbeingpresentthoughthedrawingindicatesotherwise.
• Iftherehasbeenanerrorinwiring,openingtheisolatormaynotde-energisetheswitchboarde.g.ifincorrectconnection(incorrectpolarity)occurredintheservicetoaninstallation,openingthemainswitchwillopencircuittheneutralratherthantheactive.
• Intentionallydisablinganinterlocktoperformataske.g.openingtheshutterofa‘rackable’circuitbreakertesttoprovede-energisedintheorifice.
• Inadvertentlydisablinganinterlockwhileperformingataske.g.inaswitchboardwithanintegratedcircuitbreaker,isolatorandearthswitch,theoperatoraccidentallymovingtheisolatorintotheearthedposition.
• Acombinationofpoordirectionandinsufficientknowledgee.g.aworkerisinstructedtoapplyasetofearthsandshortcircuitsataRingMainUnit(RMU).Theworkercorrectlyobservesthattheisolatorisopen.However,theworkerassumesthattheearthswitchcanbeclosedbecausetheisolatorisopen.MostRMUsareconfiguredinsuchawaythattheearthswitchearthsthecable,notthebusbar.Inthissituation,itispossiblethattheworkerwouldbeearthingandshortcircuitingalivecircuit.
• Whenapplyingasetofportableearthsandshortcircuits,accidentalorinadvertentcontactismadewithliveparts.Ifthisoccurs,theworkerisusingadevicethatisconductingfaultcurrent.
• Thethresholdvalue(lowestlevelofindicationorreading)ofatestdevicecausingamisleadinginterpretationofatesttoprovede-energised.Dependingonthedeviceused,anindicationthatpartsarenotenergised,inahighvoltagesituation,doesnotmeanthatlowvoltageanddirectcurrentvoltagesareabsent.
• Applicationofearthingandshortcircuitingdevicesthatdependonaconductivepaththroughafuseoracircuitbreakerthatisnotfitforpurpose.
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• Ineffectiveconnectiontothegeneralmassoftheearthe.g.theelectrode,gridortemporaryelectrodethattheearthfromtheearthsandshortcircuitsreliesuponinasituationwhereasinglephasebecomesenergised.
• Applicationoftheshortcircuitportionofportableearthingdevicespriortotheearthtailbeingconnectedtotheearth.
• Arcingandsplatteringassociatedwiththeapplicationofearthsandshortcircuitscausingarisk.Thearcingorsplatteringmayresultfromusingthedeviceinsituationsthatrangefromenergisedconductorstoresidualenergysuchascapacitance.Ifthepartsareenergised,theworkercandrawthearcfromonephasetotheother,causingaphasetophasefault.
• Apotentialelectricshockpathexistingoncetheearthtailisconnectedtoearth.Aworkermaytouchanotherlivepartandtheearthedconnectoratthesametime.Forexample,inaCommonMultipleEarthedNeutral(CMEN)area,evenwhenworkingonhighvoltage,contactbetweentheearthedconnectorandalowvoltagephasecancauseanelectricshock.
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B.2 Other electrical risks to be addressed
B.2.1 Working in and around trenches, pits and underground ducts
Sourcesofelectricalriskswhenworkinginandaroundtrenches,pitsandundergroundductsinclude:
• Earthedsituationsinwhichanelectricshockpathiscreatedwhenexposedlivepartsandconductivematerialsarepresentatthesametime.Examplesofconductivematerialsincludemetalpipesandliquidssuchasstormwaterorsewerage.
• Damageoflivecablewithexcavationorholeboringequipment.
• Sparkgenerationsinanexplosiveatmospheree.g.presenceofLPgas.
• Exposedliveparts.Forexample,anelectricalworkermayberequiredtoinspectandrepairadamagedundergroundcable.
Aneffectiveriskmanagementandsafesystemofworkshouldaddressrisksofthiskind.Examplesofsuitablemethodsinclude:
• Performingelectricalandassociatedworkonlyonde-energisedparts.
• Usingworkmethodsthatremovetheriskofanearthedsituatione.g.usingmatsandeliminatingoravoidingliquids.
• Ifexposedpartsofcablesarepresent,maintainingrelevantexclusionzoneuntilyoucandeterminewhetherthecableishighvoltageorlowvoltage.Ifitisdifficulttoidentify,youshouldtreatthecableaslivehighvoltage.
Constructionofhighvoltagecablesvaries.Somehighvoltagecablesareoilfilled,somearefilledwithgas,andothersrelyoninsulationonly.Acablethatisleakingoilorgasshouldbetreatedasahighvoltagecable.
B.2.2 Working with ladders, scaffolds, portable pole platforms
Workwithintheelectricalindustryrequiresextensiveuseofladders,scaffoldsandsimilarequipment.Whenusingtheseitems,youwillencounterthethreecommonelectricalrisksfromanumberofsourcesincluding:
• Aconductivedevicesuchasanaluminiumladdercreatinganelectricshockpathe.g.anelectricshockpathmaybecreatedwhenanelectricalworkerinvestigatesafaultylightcircuitifthemetalframeofasuspendedceilingisenergisedandaconductiveladderisused.
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• Movingaportablescaffoldanddamaginginsulationwhenthescaffoldstrikesconductorsorleads.
• Ifliveworkisbeingperformedfromaladderi.e.theladderslippingandcausingtheworkertotouchexposedlivepartse.g.grabbingamainsbox.
• Anincidenthappenswhileworkisbeingperformedde-energisednearexposedlivepartse.g.windblowinganextensionladderintonearbylivemainssuchasoverheadpowerlines.
• Incaseswherelinesarecarryinglargecurrents,conductivescaffoldsbecomingsubjecttoinduction.
• Inswitchroomsandswitchyards,conductivedevicessuchasaluminiumladdersandscaffoldscreatingelectricshockpathsandcurrentpathstoearthe.g.ametalwirereinforcedladdercausingafaulttogroundiftheladdertouchesalive33kVbusbar.
• Whenusingladders,scaffoldsandsimilarequipment,workersaremorelikelytotouchopenwiringsuchasoverheadlines.
Tocontrolsituationsofthiskind,ariskassessmentcouldbecarriedoutandasafesystemofworkshouldbeused.Effectiverisktreatmentmeasureswithinthissystemofworkshouldinclude:
• Usingequipmentthatisfitforpurpose,e.g.non-conductiveladders.However,suchequipmentshouldnotbetheonlyrisktreatmentmeasureusedforliveworkunderasafesystemofwork(seeAS/NZS4836).
• Usingportablepoleplatformsthatarefitforpurpose.Whenselectingaportablepoleplatform,considerationshouldbegiventousingdevicesthatcanbesafelyattachedtothestructuree.g.woodorconcreteorboth.Designanduseoftheportableplatformshouldensurethatanoperatordoesnotreceiveanelectricshockwhenoperatingthedevicecorrectly.
• Identifyingiftherearenearbyexposedliveparts.Nearbyexposedliveparts,risktreatmentmeasuressuchasde-energising,fittingcovers,usingasafetyobserver(electrical)oracombinationoftheseshouldbeaddressed.
• Employingworkpracticessuchas:
- twoormorepeoplecarryinglongdevicesinswitchyardsandswitchroomsinapositionbelowshoulderheight;
- twopeoplehandlingextensionladdersinwindyconditions;and
- restrainingladdersusingheadropesorfootropes,orboth.
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• Ifconductivescaffoldingisusedwithinhighvoltageenclosuresorinsituationswherethereisinduction,bondingthestructuretotheearthingsystem.Dependingontheconstructionofthescaffold,youmayhavetobondanumberofsectionstoensureanequipotentialstate.
B.2.3 Working with elevating work platforms (EWP)
B.2.3.1 Scope
ThispartprovideselectricalsafetyinformationforelectricalworkerswhenusingElevatingWorkPlatforms(EWP),includingscissorliftandboomtypemachines.ItoutlinesrisksassociatedwiththeuseofanEWPonlyinanelectricalcontextanddoesnotcovergeneralsafeoperation.
B.2.3.2 Risks associated with EWP usage
Elevatingworkplatformsareusedthroughouttheelectricalindustry.Theirconfigurationsandapplicationsvarywidely,buttherearecommonrisks.
Astheworkerintheplatform’sbasketmovesinthetravellingendofthemachine,theriskofcomingintocontactwithexposedliveelectricalpartsisrelativelyhigherthanforotherformsofplant.
SourcesofrisksassociatedwithEWPsusedforelectricalandassociatedworkinclude:
• Contactingexposedlivepartsandreceivinganelectricshockeveninaninsulatedmachine.Thismaybeexacerbatedbythecloseproximitytotheexposedlivepart,anymechanicalfailureoftheEWPorlossofstabilityresultingincontactwithexposedliveparts.
• Workingnearexposedlivepartsandpoorjudgementofdistance.
• Mechanicalfailureorlossofstabilitypossiblyresultingincontactwithexposedliveparts.
• Stepandtouchpotentialsbetweenvehicleandground.Thismayresultinanunsafeelectricalenvironmentwhereanotherpersonmayaccidentallytouchthelivevehiclewhilestandingontheground.
• Liveexposedpowerlinesonthegroundasaresultofpolefailureorbrokenwires.Anaccidentinvolvingmechanicalfailureofthestructurebeingworkedone.g.polefailureorliveconductorsfallingtotheground.
• Creatinganunsafeelectricalenvironmentatgroundlevele.g.ifthebodyofthevehicleislive,passersbycanreceiveelectricshocks.
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B.2.3.3 Working with an insulated EWP
Ifaninsulatedelevatingworkplatformisusedforelectricalwork,ariskassessmentshouldconsiderwhethertheEWP’sinsulationiscapableofprotectingapersonfromacurrentpaththroughthemachine.
Theinsulationdoesnotprotectapersonfromelectricshockifitispossibleforhim/hertosimultaneouslytouchanytwopartswithdifferentelectricpotentials.
Inotherwords,ifyouareperformingliveworkinthebasketofaninsulatedEWP,itisstillpossibletoreceiveanelectricshock(refertoFigure3).
Figure 3: Example of an electrocution in an insulated EWP
Anotherexampleinvolvestheapplicationofearthsandshortcircuits,suchasportableearthingdevices.Inthecaseofportableearthingdevices,youshouldaddressthelikelyeffectsofintroducingpotentialsinornearthebasket,aswellasthemechanicaleffectsoftheconductorswhippingabout,shouldthedevicebeappliedtoliveparts.
Appropriateworkpracticesshouldpreventdifferentelectricalpotentialsfromexistinginabasket.Situationslikethiscanoccurifpeopleworkonpartswithdifferentpotentials,byanearthpotentialbeingintroducedviaatestlead,orthroughaportableearthingdevice,flexibleextensionleadorpartofastructure.
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B.2.3.4 Need for planning before electrical work using an EWP
OperationsofEWPswithaboomlengthofmorethan11maredeemedaPrescribedOccupationunderschedule5oftheWorkplace Health and Safety Regulation 2008,asamended.Part3oftheWorkplace Health and Safety Regulation 2008requirescertainminimumlevelsoftrainingandassessmentbeforetheoperatorcangainthenecessarycertificatetoengageintheoccupation.Thetraining,assessmentandauthorisationofEWPoperatorswhoaretoworkinanelectricalcontextshouldbeequivalentto,orbetterthan,theworkplacehealthandsafetyrequirements.
Beforeelectricalworkersperformanyelectricalworkfromanelevatingworkplatform,ariskassessmentshouldbecarriedoutandsafetyissuesaddressed.Theseissuesvarydependingonsuchconditionsasthejob,location,orweather.Thoughnotexhaustive,thefollowinglistmaybeofassistancetodeterminesuitabilitytoperformwork:
• Doestheworkerholdtheappropriateelectricalqualification?
• IstheelectricalworkerfamiliarwiththeprocedureandmethodassociatedwiththeelectricalworkusingtheEWP?
• Istheelectricalworkersufficientlyfamiliarwithtoolsandequipment,suchaschainsawsoraugers,tousethemsafelywhileexposedtotheadditionalrisksassociatedwithanEWPnearexposedliveparts?
• WilltherebeasuitablyqualifiedEWPoperatoroperatingthemachine?
• IstheEWPoperatorfamiliarwiththeparticularmachine?
• WherespecialtestingoftheEWPandequipmentisrequirede.g.strengthandinsulation,areallthetestsuptodate?
• Areappropriatepersonsonsiteabletosafelyperformarescueincaseanaccidentoccurs?
TheEWPoperatorshouldensurethatallchecks,inspections,set-up,stowageandmaintenancerequirementsoftheprimemover–aswellastheEWPportionoftheplant–arecompliedwith.Thechecks,inspections,set-up,stowageandmaintenanceforeachmachineshouldbeclearlydocumented.ThoughmanyoftheserequirementsaresimilartogeneralEWPrequirements,inelectricalsituationsthereareoftenadditionalrequirementssuchascleaningtheinsulatingparts.
Peopleshouldremaininthebasketwiththeirharnessattachedatalltimeswhenthebasketismovedfromthecradle.Theonlyexceptioniswhenadocumented
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safesystemofworkisinplacetoprovideasafealternative.Ifthesafesystempermitsaccessoregress,orboth,fromanEWPbasketinaraisedposition,thisproceduremustbefollowedtotreattherisksassociatedwiththisaction.Theserisksincludefallsfromheightsandelectricshock.
AsafesystemofworkassociatedwithelectricalworkfromanEWPwillinvariablyincludetraining,assessment,authorisationandauditingcomponents.Suchcomponentsaregeneraltomachinesaswellasspecific.Additionally,thesafesystemshouldconsideratleastthefollowingcontingencyplansthatinstructoperatorsonhowtodealwithsituationsthatinclude:
• Mechanicalfailureorelectricalormechanicalaccidents,orallthree.Usingthefollowingmayprovidesolutions:
- groundcontrols;
- bleedvalves;
- batteryoperatedsystems;
- controldescentdevices;and
- escapedoorsandhatches.
• Fireinthehydraulicsystem,possiblyatbasketlevel,includinganincidentinwhichtheoperatorslumpsoverthecontrols,activatingthe‘deadman’aswellasoneofthecontrols.By-passvalvesatgroundlevelmaycaterforsuchsituations.
• Therolesofallpersonsonsitewithelectricalsafetyresponsibilitiesshouldbeclearlydocumentede.g.theroleofthebasketoperatorandtheinterrelationshipwithgroundoperatorsandanysafetyobservers.Communicationneedsshouldbedefined,asshouldanyactionsrequiredifdirectcontactismadewithexposedliveparts.
• AsafesystemofworkshouldalsoincludesuitablecontrolsforsafelyoperatingtheEWP.TheoperatorshouldbeabletousethecontrolseasilywhilewearingthePPErequired.Additionally,designoftheoperatorinterlockdevice(deadman)shouldensureitcannotbeeasilybypassedbytheoperatorinthebasket.
• Asafesystemofworkshoulddetailtherequirementsforchecks,inspections,set-up,stowageandmaintenance.Theoperationalcheckshouldincludesafetycomponentssuchasdeadmanswitchesandcontroldescentdevices.Inaddition,thecorrectoperationofmultipleparkbrakes,powertake-offsandhydraulicaccumulatorsshouldbedetailed.
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• Theprocedurefortestingthemachineelectricallyandmechanicallyshouldcomplywithrelevantstandards.
• Ifthesafesystemofworkincludeslivework,risktreatmentmeasuresshouldnotcreatedangerousstepandtouchpotentials.Atastrategiclevel,youshoulddeterminewhethertoadoptorrejectthepracticeofearthingthemachineframe.Regardlessofthemethodchosen,appropriatetechnicalconsiderationisrequired,sinceeachmethodhassignificantadvantagesanddisadvantages.Athoroughanalysisshouldinclude:
- thepieceofplantbeingused;
- thetasksbeingperformed;
- configurationoftheelectricalnetwork;and
- theeffectofelectricalsafetyonworkersandpublic.
• WheretheEWPworkistobeperformedondistributionand/ortransmissionassets,privateorotherwise,thefollowingpointsshouldbeaddressed:
- Ensuringthatsafeapproachdistancesaremaintained.
- Makingsurethatstepandtouchpotentialsonandaroundthestructuredonotcauseriskse.g.fromfaultsorleakage.
- Beforeworkstarts,ensuringthatthemechanicalintegrityofthestructure,conductorsandequipmentattachmentshasnotorwillnotbecompromisede.g.consideringwhetherthestructureissafeforworkwithoutfurtherrisktreatmentmeasures.
- IfconductorsarepermittedtocomeintocontactwiththeboomorbasketoftheEWP,asafesystemofworkshouldclearlystatetheelectricalandmechanicalrequirementsforthispractice.
- Detailingtheauthorisations,licences,restrictionsandrequirementsinworkpracticestobeusedifboomsandbasketsaretoworkbetween,nearandoverenergisedandde-energisedaerialworksandinstallations.Thislistshouldincludeelectricalandmechanicalspecificationsincludingfail-safesystems.
B.2.3.5 Special provisions for working in the safety observer danger zone
What is the safety observer danger zone?
Anelevatingworkplatformisconsideredtobeoperatinginthesafetyobserverdangerzonewhenthereisapossibilitythatanyofthefollowingiscapableofenteringtheexclusionzoneofexposedlivepowerlines.
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• anypartoftheEWPnotdesignedandcapableofworkingsafelywithinthearea;
• anyhandtoolsorotherequipmentheldbyanypersoninvolvedwiththeoperationandnotdesignedorcapableofworkingsafelywithinthearea;
• theloadbeingmoved;or
• thepersonworkingonanelevatingworkplatform.
Anelevatingworkplatformisnotoperatinginasafetyobserverdangerzonewhen:
• thepowerlineshavebeende-energised;
• limitingswitcheshavebeeninstalledtowarntheoperatororpreventanypartoftheEWPorloadfromenteringtheno-goexclusionzone;or
• anypartsoftheEWPbeingmovedarebeingpreventedfromenteringtheexclusionzonebyphysicalbarriers.
ThesafetyobserverdangerzonesforpowerlinesonpolesandontowersareillustratedinFigure4:Safetyobserverzoneforoverheadpowerlinesonpoleandtowers.
Figure 4: Safety observer zone for overhead power lines on poles or towers
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Boom configuration
Boomconfigurationshouldalsobeaddressed.Elevatingworkplatformsusedintheelectricityindustryincludetelescopic,‘knuckle’andscissorbooms,flyjibsandhybridversions.Theappropriateboomconfigurationcanassistorhinderelectricalsafetyandneedstobeaddressedinriskmanagement.
AnexampleofapossibleriskcanbeseeninFigure5.
Figure 5: Example of a risk due to the position of the vehicle and boom configuration (worker performing de-energised work in an uninsulated EWP)
Safety observer
Asafetyobserverisrequiredwhenanelevatingworkplatformisoperatedwithinthesafetyobserverdangerzone.TheemployeroftheEWPoperatororaself-employedoperatorisresponsibleforappointingasafetyobservertoobservetheapproachoftheEWPorloadtopowerlines.
People in contact with the EWP
Whentheelevatingworkplatformoperatesinthesafetyobserverdangerzone,onlythefollowingpersonsmaybeinstructedtotouch,orallowedtotouch,anypartoftheEWPoritsload:
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• Theoperatorwhilenotincontactwithanelectricalearthoranothersourceofpotential.
• Anoperator,whilestandingonthegroundorwhileinanearthedsituation,mayoperatetheEWPunderthefollowingconditions:
- thecontrolsareeffectivelyinsulated3;
- theoperatorwearsinsulatinggloveswherethevoltageofanyoftheoverheadpowerlinesdoesnotexceed1000volts;or
- theoperatorstandsonanequipotentialmetallicmatortray/deck,electricallyconnectedtoallmetalworkassociatedwiththecontrols.
• Otherpersonnelmaybeallowedinthesafetyobserverdangerzoneonconditionthat:
- theirpresenceisessentialtotheparticularoperationofthecraneorplante.g.otherworkershelpingtosetuptheEWP;
- thesepersonsarenotrequiredtohavedirectcontactwithanypartoftheEWP;
- wheredirectcontactisnecessary,effectivelymaintainedinsulatingglovesmustbeworn;and
- whenanyindirectcontactisrequiredbythesepersonswiththeEWP,suchcontactmustbeviaanon-conductiveobjecte.g.haulingline,poleortailropeusedtocontrolloadmovement.
B.2.3.6 Additional loading affecting movement or position of the EWP basket
Whenconsideringtherisksassociatedwithworkingonornearstructures,youshouldallowforthefactthatthemechanicalloadingofthestructurecanbesignificantlyalterede.g.addingadditionallightfittingtoalighttower,orapplyingorremovingtensionfromaerialconductorsorcatenarysystems.
Amechanicalfailureofthiskindcancompoundrisksanddramaticallyincreasetheriskandconsequences.Forexample,ifthetiploadingofapoleisalteredandapoleconsequentlyfails,thefallingpolemaystriketheEWP.Atthesametime,however,livemainsmayfalltotheground,creatingrisksforworkcrew,rescuersandthepublic.
3 Insulationmustatleastbeeffectiveagainstthemaximumvoltageoftheparticularoverheadpowerline.Theemployerorself-employedpersonoperatingthecraneisresponsibleforensuringtheeffectivenessoftheinsulationinaccordancewiththerelevantStandard.
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Theelevatingworkplatformshouldnotbesubjectedtomechanicalforcesforwhichitisnotdesigned.Forexample,inappropriateconductortensioningtechniquesorraisingandloweringwithapowerwinchcouldapplyinappropriateforcetoanEWP.
B.2.3.7 Possible illusions as a result of using an EWP
Operatorsshouldbeawareofafeelingoflight-headednessascloudsmoveinthebackgroundoraffecttheoperator’speripheralvision.
Inaddition,whereworkisperformednearaerialconductors,operatorsshouldbeawareofanillusionknownas‘wireblindness’.Thisstateoccurswhenanoperatorknowsthataconductorexistsbuteithercannotseeitorlosessightofit.Inthesecircumstances,adequatecontingenciesshouldbeemployed.
B.2.4 Working on or from poles and towers
Sourcesofriskswhenworkingonorfromapoleortowerinclude:
• Electricshocksfrommultiplesourcesofpotential,oftenuninsulatedanduncovered.Thesesourcesinclude:
- highvoltagecircuits;
- lowvoltagecircuits;
- multipleandcommonearthsystems,includingaerialearths;
- streetlightmainsthattestasbothanactiveandaneutraldependingonthestatusofthecontrolcontractor;
- earthedmetalworkandlightingarrestors;and
- earthedcatenarysystemssuchashighvoltageaerialbundledconductor,pilotwiresandbroadbandcommunicationcable(BBCC–cableTV).
• Clashingofconductorsandconductorscontactingothercircuits.
• Stepandtouchpotentialsatgroundlevelandabove.Thesemaybecausedbyanumberoffactorsrangingfromfailinginsulatorstoincorrectconnections(includingincorrectpolarity).
• Failureofconductors,cross-armsorpoles,creatingrapidmovementsthatcancauseworkerstotouchenergisedparts.
• Injuryandillnessfrom‘suspensiontrauma’.Ifrestrainedafterafall,apersonmaysuffer‘suspensiontrauma’iflefthangingintheharness.
• Workingnearexposedlivepartse.g.workingonde-energisedlowvoltagewhilethehighvoltageaboveisenergised.Thishasrisksassociatednotonlywiththehighvoltagebutwithhighvoltagecausinginductioninthelowvoltage.
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• Effectsthatmaybebeyondtheimmediatecontroloftheworkgroupincluding:
- lightning;
- windgustscausingmovementaswellasstaticeffects;and
- vehicleshittingpoles.
Electricalworkandassociatedworkonorfromapoleshouldbeperformedonlyafterariskassessmenthasbeencarriedoutandthenonlyinlinewithaneffectivelyimplementedsafesystemofwork.
Workshouldnotbeginuntilthepolehasbeenexaminedandevaluatedassafetoclimborworkon.Therequirementforanexaminationshouldapplyregardlessof:
• thetypeofstructurei.e.wood,steelorconcrete;
• whetherapoleisownedbyasupplyentityornot;and
• whethertheworkistobeperformedfromthepoleorfromanotherdevicesuchasanelevatingworkplatform.
Aspartoftheexaminationandevaluation,abelowgroundinspectionmaybenecessary.
Wherethetiploadingisbeingaltered,workproceduresshouldincludemethodsthatwillpreventstructuralfailure.Further,anengineeringassessmentshouldbeconductedifthetiploadingistobealteredpermanentlyorwhereworkprocedurescannotensurestructuralstability.Ifloadingofapoleisalteredconsiderationshouldbegiventotheeffectthismayhaveonadjacentpoles.
Structuresandinsulatorssupportinglivehighvoltageconductorsshouldbecheckedtoidentifyconditionsthatmayresultinleakagethroughthepole.Whereleakageissuspected,furthertestsshouldbedonetodeterminewhetherthestructureissafetoclimb.
B.2.4.1 Work practices
Asafesystemofworkthatiseffectiveinensuringelectricalsafetyshouldensureatleastthefollowing:
• clearinstructionsaregivenaboutworkingliveandde-energised;
• isolationandaccessareintroducedtocreateanelectricallysafeenvironment;
• requirementsforalteringloadingsonstructuresarecommunicated;and
• thestabilityofthestructureisassessedasadequate.
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Thefollowingprecautionsshouldbetakenwhenpolesandtowersareworkedon:
• Whenconductorsarereleasedortensioned,tensionshouldbealteredinawaythatcontrolstheireffectonstructuralstability.
• Inparticular,conductorsshouldnotbecutandallowedtofall.Thispracticemaycausedangerouswhip,leadingtostructuralfailure.
• Additionalorheaviermainsshouldbetensionedsothatanoverallbalanceintensioniscloselymaintainedonthecrossarmandpole.
• Crossarms,armchecks,boltholes,boltsandthepoleheadshouldbeexaminedfordeteriorationorweaknessbeforeheavierormoreheavilytensionedconductorsareadded.
• Workpracticesshouldalsoensurethatobjectsarenotdroppedorallowedtofallfromheights.
B.2.4.2 Wooden poles
Forwoodenpolesownedbyanelectricityentity,theexaminationshouldincludeacheckformarkingssuchas’suspect’(onediagonalpaintedstripe)or’unserviceable’(paintedcross).Forotherpoles,workersshouldconsulttheassetowneroroperator.Fungusandloosesapwoodshouldnotobscurethesemarkings.
Structuralintegritycanbecheckedbyusinganappropriatemethodsuchasaropetest.Wherearopetestcannotbesafelyorpracticallycompleted,asuitableprocedureforidentifyingpoledefectsshouldbeused.
Ifapoleisnotmarkedassuspectorunserviceable,itshouldbetestedtoensurethatthepoleissafetoclimboraccess.Inthiscase,thefollowingtestsshouldbeconsidered:
• aropetest;
• abelowgroundinspection;and
• ‘sounding’thepolebyusingahammerormaultodetectunsoundstructures.
Duringthesetests,appropriateactionshouldbetakentoensureco-workersandothersaresafefromfallingobjectsetc.
A‘laddertest’–oranyothermethodoftestingapolebyimposingpressureviaaladder–shouldnotbeusedasanappropriatewayofdeterminingifapoleissound.
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B.2.4.3 Concrete poles
Concretepolesareconductive,especiallywhenwet.Theconductivityoccursboththroughmetalfittingsconnectedtothereinforcementandthroughtheconcretesurface.Therefore,thesurfaceofaconcretepoleandallmetalworkbolted,clampedorbondedtoaconcretepoleshouldbetreatedasconductive.Takeappropriaterisktreatmentmeasuressuchasusingbarriersandinsulatedmats.
B.2.4.4 Steel poles
Withsteelpoles,internalandexternalcorrosioncancreatetheriskofstructuralfailure.Inspectionandtestingshouldincludeanysignsofcorrosion-inducedstructuraldamage.
Thisshouldincludethefollowingtests:
• aropetest;and
• abelowgroundinspection.
Duringthesetests,appropriateactionshouldbetakentoensureco-workersandothersaresafefromfallingobjectsetc.
Steelpoleshavevariousshapesandsizes.Safeworkpracticeswhenusingaladderandpoleplatformsneedtoensurethatthedevicescanbefittedsoundly.Safeworkpracticesshouldincludepreventingpeoplefromfallingfromheights.
B.2.4.5 Working on unserviceable or suspect poles
Insomecases,additionalstrengtheningandsupportmaynotbeinstalledbeforeworkisdoneonan’unserviceable’or’suspect’pole.
Whenthishappens,anappropriatelyexperiencedandqualifiedpersonshouldevaluatethepole’sconditiontodecidewhetherthepolecanbesafelyclimbed,workedon,orboth.Additionalmeasurestoensuresafetymayinclude:
• Securingthepole’sbasebydrivingatleastthreelonggadsintothegroundaroundthepoleandthenlashingthemtoit.Theheadofthepoleshouldalsobesecured,usingatleastthreestaysattachedashighaspossible.
• Holdingthepoleatheadandgroundlevelwithapolelifterorcraneofsuitablesize.
• Attachingsuitablestayequipmentthatwillholdthepoleuprightunderallconductortensionsandsubsequenttwisting.
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• Whenthereplacementpoleiscloseenough,performworkassociatedwiththeoldpolebyworkingfromthenewpole.Theoldpoleshouldbelashedtothenewoneandstayed,sothatwhenconductorsarereleased,theoldpolewillnotfall.
Polebuoysorpikesmayprovideasatisfactorytemporarymeansofsupportingbadlydeterioratedpoles.Whenapolehastobeclimbed,polebuoysrequireadditionalstayingifusedforsupport.Otherwise,polebuoysarenotsuitableforthetask.
Whenreleasingconductorsfromanunserviceablepole,holdtheconductorsundercontrolandreleasethemslowlysothatyoucannotetheireffectonthepolebeforeyoureleasethemcompletely.Ifpolestabilitydependsontheconductorsbeingreleased,additionalstaysshouldbeinstalledtomaintainorincreasestability.
Ifthepolecannotbeheldorsupportedsothatalltheconductorscanbesafelyremoved,noattemptshouldbemadetoclimborworkonthepoleuntilitissafetoperformthework.Thepoleshouldbemadeassecureaspossiblewithavailableequipment.
B.2.4.6 Electrical leakage procedures for poles
Beforeclimbinganypolesupportinglivehighvoltageconductors,makeavisualinspectionforanyevidenceofleakage.Ifyouseeevidenceofpoletopfiresorotherfiredamage,damagedorpollutedinsulators,oraconductor,tiewireordebristouchingthepoleorcrossarm,youshouldensurethepoleistestedorinspectedfordamageorboth.
Whenconductorattachmentscannotbeclearlyassessedfromthegroundbecauseofwetweatherorpoorvisibility,adetection/inspectionshouldbecarriedout.
Whereleakageissuspectedonpolessupportingbroadbandcommunicationcables(BBCC),appropriateproceduresshouldbeusedtodetectleakage.Theseproceduresshouldaddresstherisksassociatedwithtestingnearexposedhighandlowvoltageconductors.TheyshouldalsolookatwhetheranyleakagethroughaBBCCsupportingconductormightaffectthedetection’svalidity.
Whereleakageissuspected,workshouldnotbecarriedoutuntilthepolehasbeenconfirmedsafetoworkonorfrom.
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Figure 6: Rope pull test
B.2.4.7 Rope testing
Thefollowingitemsshouldbeaddressedwhenperformingaropetestonapole:
• Ensuremembersofthepublicandworkersaresafe.
• Thefollowingprocessshouldbeconsidered:
- extendaladderwithropeattachedtothetopstileorheadoftheladderasfarupthepoleaspractical;
- applypressureascloseaspossibletotheheadofthepoleonthesideorinthedirectionleastsupportedbystaysorconductors;
- twopeopleshouldpullontheropeorropeswhilestandingasfaraspracticalfromthebaseofthepole;theropepullersshouldbelocatedontheoppositesideofthepolefromtheladder(refertoFigure6–Ropepulltest);and
- duringthetest,pressuremustbeappliedprogressivelyorgradually;avoidaggressiveorjerkyactions.
• Theropemustbelongenoughtoensureoperatorsaresafeifapoleshouldfail.
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• Signsoffailureincludeexcessivemovement,signsandsoundsofsplitting.
• Otherpeopleshouldbekeptoutoftheareaduringthetest.
• If,duringaproceduretodeterminewhetherthepoleisstable,thereisanydoubtaboutthepole’ssoundness,thepolemustberegardedas‘suspect’.Providepolesupportbeforeproceedingfurther.
B.2.5 Tagging out of service
Whenequipment,partsordevicesarenottobeused,theitemoritemsshouldbemadesafe(e.g.isolated)andtaggedoutofservice.Examplesofwheretaggingoutofserviceshouldoccurinclude:
• toolsandequipmentthatarefaulty,defectiveoroutoftestdate;and
• plantandequipmentthatisunsafe,underrepairorbeingmaintained.
Taggingoutofserviceisarisktreatmentmeasurethatphysicallyexcludesitemsfromuseandshouldformpartofasafesystemofwork.Tagsusedshouldcomplywithanappropriatestandard(refertoalsoPart3.4.2).
B.2.6 Excavation near energised cables
Workersinvolvedinexcavationshouldbeawareofthepossibilityofelectricshockandexplosionsassociatedwithdamagedundergroundcables.Itcanbedifficulttotellthedifferencebetweenhighvoltageandlowvoltagecables.Thereisapotentialforinjuryanddeathiflowvoltageandhighvoltagecablesaredamaged.
Evenearthed,metal-sheathedcablescancauseinjuriesifdamaged,becauseprotectivesystemsmaynotalwaysoperatefastenoughtopreventinjury.
B.2.6.1 Precautions before excavation
Beforeexcavation,youshouldcontacttheorganisationDialBeforeYouDig4,afreeenquiryreferralserviceforinformationonundergroundassetsanywhereinAustralia.Forfurtherinformation,contactDialBeforeYouDigbyanyofthefollowingmethods:
4 DialBeforeYouDigcontactsmemberassetownerswhohaveservicesatorneartheproposedexcavationsiteandwillarrangeforinformationabouttheseservicestobesent.Assetownerswillusuallyrespondwithintwoworkingdaysandmayprovidecopiesofundergroundserviceplans.ItmustbeemphasisedthatDialBeforeYouDigisareferralandinformationserviceonlyandisnotthelegalownerofsiteinformation.DialBeforeYouDigdoesnotgoon-siteandfindthephysicallocationoftheundergroundservice.
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• telephone1100;
• fax1300652077;or
• onlineatwww.dialbeforeyoudig.com.au.
B.2.6.2 Using mechanical excavation equipment
Asafesystemofworkshoulddeterminebeforehandhowclosemachinery,suchasbackhoes,excavators,horizontalborersandchaindiggers,canexcavatenear:
• cablesorcablejoints;
• earthsystemsorgrids;
• conduitsorducts;
• undergroundpillars,pitsorequipment;and
• cableprotection(mechanical)suchascovertiles,slabsorstrips.
Ifitisnecessarytoexcavateneartheitemsabove,theworkshouldbedonebyhandexcavationorwithhandtools.
Theplantoperatorshouldbeguidedbyanotherworkerpositionedtowarntheoperatorifthemachineappearslikelytoventuretoocloseortocausedamage.
Pneumaticorotherpoweredexcavationtools,suchasjackhammers,shouldnotbeusednearconduitsthatcontainlivecables.
Whenusingpoweredtoolstoexcavatebesideorarounddirect-laidcablesinrockorhardfill,existingcablesshouldbeprotectedincasethemachineslips.
B.2.6.3 Excavating concrete-encased conduits
Excavatingconcrete-encasedconduitscontaininglivecablescanbehazardousifappropriateprecautionsarenottaken.Explosionsandelectricshockcanresult.
Itispreferabletoremovecablesfromtheconduitwhiletheworkisdone.
Ifthecablescannotberemoved,theyshouldbede-energised.Handexcavationshouldbeused,atleastuntilenoughofanopeninghasbeenmadeintheconduittopermittheinstallationofmechanicalprotection.
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B.2.7 Vegetation management, chainsaws and electrical workers
Ifanelectricalworkerisrequiredtoperformvegetationmanagementnearexposedliveparts,anumberofadditionalrisksshouldbemanaged.Typically,thisworkrangesfromclearingvinesthathavegrownintoaswitchboardtotrimmingtreestomaintainclearancesfromoverheadpowerlines.
Inadditiontorisksassociatedwithgeneralvegetationmanagementandchainsawuse,electricalrisksinclude:
• Asituationwhereobjectsfallagainstenergisedconductors.Theconductorsmayormaynotbebaree.g.treetrimmingfromgroundlevelwherethetreeorpartofthetreemaytouchexposedliveparts,causingstepandtouchpotentialsatgroundlevelormainstoclashorboth.
• Asituationwhereobjectsfallacrossorontoconductorse.g.whenremovinganunserviceablewoodenpolelocatedbetweenenergisedmains,objectsshouldnotbeallowedtofallacrossconductors.Anincidentofthiskindcancreateelectricalormechanicalrisksorboth,forexample,bycausingaliveconductortofalltotheground.
• Thelikelihoodofacurrentpaththroughthevegetationshouldalsobeaddressed.Aworkermayreceiveanelectricshockviathevegetationorcauseafaultorboth.Currentmaytracktoearthorbetweenphasesviathevegetation.
B.2.8 Use of tools
Pooruseoftoolscanexposeworkerstoelectricalrisksincluding:
• electricshockandexplosionifanenergisedcableiscut,regardlessofwhetherbycablecuttersorahacksaw;
• strippingcablecancauseinjuriesrangingfromelectricshocktoburnsandcuts;and
• tighteningconnectionscancauseshortcircuitsandexplosionse.g.aspannercanslipandbridgetwophases,resultinginburns.
Thesetoolsshouldbeusedaccordingtomanufacturer’sinstructionsandaneffective,safesystemofwork.
Toolsshouldberestrainedattheworkpositiontopreventthemfromfallingintoliveswitchboardsorjammingcontrolse.g.inanEWP.Theuseoflanyardsaround
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wrists,toolholdersandtoolrestraintsincludingtoolpouchesandbaskets,shouldbeaddressed.
ReferalsotoPart4.4forfurtherinformationontools,instrumentsandequipment.
B.3 General elements of a safe system of work
AsafesystemofworkisspecifiedintheRegulationandisdescribedinAS/NZS4836.Generally,forasafesystemofworktoexist,peopleshouldbeabletodemonstratethattheyhaveidentifiedandaddressedrisksassociatedwithworkers’safety.
Typically,thereshouldbeplanningandpre-preparedactions,recordsandevidencethattheactionshavebeenaddressed.
RefertoPart4.3forrequirementsforasafesystemtoperformlivework.
Commonelementsofasafesystemofworkthatshouldapplytoallelectricalwork,bothliveandde-energised,include:
• thesafesystemofworkshouldbedrawnupwithpeople,whoarerepresentativeofelectricalworkers;
• thesystemshouldbeconsistentwith,andshouldcomplement,othermanagementsystemssuchasgeneralworkplacehealthandsafety,environmentalsystems,andqualitysystems;and
• asafesystemofworkshouldincludepracticalguidanceonatleastthefollowing:
- electricalaccess;
- physicalaccess;
- safeelectricalworkpractices;
- tools,instrumentsandsafetyequipmentusedforelectricalwork;and
- testingandfaultfinding.
B.4 High voltage isolation and access
B.4.1 General
Relevantriskslistedin4.3ofthisCodealsoapplytohighvoltage.Additionalsourcesofrisksforhighvoltageisolationandaccessinclude:
• inductionfromothercircuitsandcommunicationsequipmentsuchasradiotransmitters;
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• buildupofstaticchargesduetoweatherconditions;
• ferro-resonance;
• transferredearthpotentials;
• feedbackfromsecondaryortertiarysystems;
• storedenergyinhighvoltagecapacitorbanks;and
• workingunderoroverotherliveconductors.
Fromanelectricalsafetyperspective,therisksandconsequencesofanincidentinvolvinghighvoltagearesignificantlyhigher.Underfaultconditions,thehigherpotentials(voltages)andfaultcurrentlevelsreleasemassivequantitiesofenergy.Risktreatmentmeasuresshouldbeadoptedtoreduceexposuretotheserisks.
B.4.2 High voltage isolation and access system
PeoplenearexposedlivehighvoltagepartsmustmaintaintheexclusionzonelimitsdetailedinAppendixCofthisCode.Undersection64oftheRegulation,wherepeopleintrudewithintheexclusionzonelimitsforexposedlivehighvoltageparts,thepartsmustbede-energisedandearthedandtestedtoconfirmthatitisisolatedfromallsourcesofelectricity.
TheprinciplesinPart2.3ofthisCodealsoapplytohighvoltage.Elementsofasafesystemofworkforhighvoltageisolationandaccessshouldinclude:
• Amechanismtoinstructpeopleonwhattoisolatetopermitaccesstothehighvoltagepartsaswellastosurrenderaccessandreverseisolation,andhowtodoit.
• Effectiveisolationtopreventlightning,switchingsurgesorothereventsfromcompromisingtheisolationpointorpoints.Electricalsafetyintheareaforaccessshouldnotbecompromised.
• Workpracticesanddevicesusedforearthingandshort-circuitingshouldbecapableofwithstandingthevariousprospectivefaultcurrentlevelsandclearingtimesorfaultduration.
• Exceptinemergencysituations,authoritytoaccesshighvoltagepartsthathavebeenearthedandshortcircuitedshouldbeprovidedbywayofawrittenpermitorauthority.Thepermitorauthoritymaybeissuedbytelephoneorradioetc.
• Inemergencysituationstheactionstakenshouldberecorded.
• Testingtoprovede-energised.
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• Wherepossible,workandaccessshouldoccurwithvisibleearthsandshortcircuitdevices.
• Placementof’otherprecautions’shouldbearisktreatmentmeasurefordirectingpeopletoelectricallysafeworkareas.Otherprecautionsusuallyinclude:
- tapingorropingoff;
- safetysigns;and
- barriers.
• Amechanismorprocessimplementedthatdemonstratesthattheisolationandaccessprocessisbeingcompliedwithatalllevels.
• Havingmechanismsinplacetodealwithprotectionoperationsthatminimiseexposuretoelectricalrisks.Ifafeedertripsor‘locksout’,whetherornotafterre-closing,theactionstoenergisethefeedershouldbeoutlined.
• Effectiveisolationtoincludecontrolcircuitsandsecondarysystems.Unlessfitforpurpose,anopenhighvoltagecircuitbreakershouldnotbeconsideredaneffectiveisolationpoint.
• Proceduresormechanismstobeinplacetoaddressworkerandcommunitysafetyinemergenciese.g.damagefromcyclones,mainsontheground.
Earthinginstalledinapowersystemisonemethodusedtopreventorminimiseelectricshocks.Whenoperatingapowersystem(e.g.toswitch,de-energise,isolate,provede-energised)additionalriskscouldbepresent.Forexample,whenapowersystemisoperated,voltagetransientsofshortdurationcancreatelethalstepandtouchpotentials.Transientscanoccurwhennetworkoperationscausehugequantitiesofelectricalenergytostopflowingsuddenly.
Asitisforeseeablethatlethallevelsofstepandtouchpotentialwillexist,appropriaterisktreatmentmeasuresshouldbeused.Dependingonthesituation,methods,oracombinationofmethods,thatshouldbeconsideredinclude:
• Designandinstallationmeasures:
- physicallyseparateorisolatearticlese.g.mounttheequipmentinasafelocationsuchasabove2.4metres;and
- usealternativeinsulation,betterearthing,orboth.
• Operationalmeasures:
- useofinsulatingglovesormats,orboth,whenperformingsystemoperations;or
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- useofequipotentialzoneswhereconductivematerialscreateazonearoundtheworker,sothattheeffectsofstepandtouchpotentialsarenegligible.
Ifinsulatingglovesormatsorbotharechosen,theyshouldbeusedinatleastthefollowingsituations:
• operatinghighvoltageisolators,switchgearandearthswitchesviahandles,operatingrodsandsimilarequipment;
• applyingandremovingportableearthsandshortcircuits;and
• usinghighvoltagetestdevices,operatingrods,measuringsticksetcon,ornear,highvoltageparts.
88
Appendix C: Exclusion zones for electrical parts
Thesetablesareareproductionofschedule2fromtheRegulation.
Part 1: Exclusion zones for exposed parts for UNTRAINED PERSONS and for operating plant and vehicles operated by untrained persons
Nominal phase to phase voltage of
exposed part
Untrained person for the exposed part
(mm)
Operating plant operated by untrained
person for the exposed part (mm)
Vehicle operated by untrained person
for the exposed part (mm)
Low voltage (with consultation with person in control of exposed part)
1 000 3 000 600
Low voltage (without consultation with person in control of exposed part)
3 000 3 000 600
Above low voltage, up to 33kV (with consultation with person in control of exposed part)
2 000 3 000 900
Above low voltage, up to 33kV (without
consultation with person in control of exposed part)
3 000 3 000 900
Above 33 kV up to 50 kV
3 000 3 000 2 100
Above 50 kV up to 66 kV
3 000 3 000 2 100
Above 66 kV up to 110 kV
3 000 3 000 2 100
Above 110 kV up to 132 kV
3 000 3 000 2 100
Above 132 kV up
to 220 kV
4 500 6 000 2 900
Above 220 kV up to 275 kV
5 000 6 000 2 900
Above 275 kV up to 330 kV
6 000 6 000 3 400
89
Nominal phase to phase voltage of
exposed part
Untrained person for the exposed part
(mm)
Operating plant operated by untrained
person for the exposed part (mm)
Vehicle operated by untrained person
for the exposed part (mm)
Above 330 kV up to 400 kV
6 000 8 000 4 400
Above 400 kV up
to 500 kV
6 000 8 000 4 400
Nominal pole to earth dc voltage of exposed part
+/- 25 kV 3 000 3 000 900
+/- 85 kV 3 000 3 000 2 100
+/- 150 kV 3 000 3 000 2 100
+/- 270 kV 4 500 6 000 2 900
+/- 350 kV 5 000 6 000 2 900
+/- 400 kV 6 000 6 000 3 400
Part 2: Exclusion zones for exposed parts for AUTHORISED AND INSTRUCTED PERSONS and for operating plant and vehicles operated by authorised or instructed persons
Nominal phase to phase voltage of
exposed part
Authorised person or instructed person for the exposed part
(mm)
Operating plant operated by
authorised person or instructed person for the exposed part, with safety observer
or another safe system (mm)
Vehicle operated by authorised person
or instructed person for the exposed part
(mm)
Low voltage (with consultation with person in control of exposed part)
(No exclusion zone prescribed)
1 000 600
Low voltage (without consultation with person in control of exposed part)
(No exclusion zone prescribed)
1 000 600
Above low voltage, up to 33kV (with consultation with person in control of exposed part)
700 1 200 700
90
Nominal phase to phase voltage of
exposed part
Authorised person or instructed person for the exposed part
(mm)
Operating plant operated by
authorised person or instructed person for the exposed part, with safety observer
or another safe system (mm)
Vehicle operated by authorised person
or instructed person for the exposed part
(mm)
Above low voltage, up to 33kV (without
consultation with person in control of exposed part)
700 1 200 700
Above 33 kV up to 50 kV
750 1 300 750
Above 50 kV up to 66 kV
1 000 1 400 1 000
Above 66 kV up to 110 kV
1 000 1 800 1 000
Above 110 kV up to 132 kV
1 200 1 800 1 200
Above 132 kV up
to 220 kV
1 800 2 400 1 800
Above 220 kV up to 275 kV
2 300 3 000 2 300
Above 275 kV up to 330 kV
3 000 3 700 3 000
Above 330 kV up to 400 kV
3 300 4 000 3 300
Above 400 kV up
to 500 kV
3 900 4 600 3 900
Nominal pole to earth dc voltage of exposed part
+/- 25 kV 700 1 200 700
+/- 85 kV 1 000 1 800 1 000
+/- 150 kV 1 200 1 800 1 200
+/- 270 kV 1 800 2 400 1 800
+/- 350 kV 2 500 3 200 2 500
+/- 400 kV 2 900 3 600 1 900
91
Part 3: Exclusion zones for low voltage overhead insulated electric line for UNTRAINED PERSONS and for operating plant or vehicles operated by untrained persons
Low voltage overhead insulated electric line
Untrained person (mm)
Operating plant operated by untrained person for the electric
line (mm)
Vehicle operated by untrained person for the electric line (mm)
With consultation with, and insulation verified by, an authorised person for the electric line
(No exclusion zone prescribed)
1 000 300
Without consultation with, and without insulation verified by, an authorised person for the electric line
3 000 3 000 600
Part 4: Exclusion zones for low voltage overhead insulated electric line for AUTHORISED OR INSTRUCTED persons and for operating plant or vehicles operated by authorised or instructed persons
Low voltage overhead insulated electric line
Authorised person or instructed person for the electric line (mm)
Operating plant operated by
authorised person or instructed person for the electric line, with
safety observer or another safe system
(mm)
Vehicle operated by authorised person or instructed person for the electric line (mm)
With consultation with, and insulation verified by, an authorised person for the electric line
(No exclusión zone prescribed)
(No exclusion zone prescribed)
(No exclusion zone prescribed)
Without consultation with, and without insulation verified by, an authorised person for the electric line
(No exclusion zone prescribed)
1 000 600
92
Part 5: Exclusion zones for high voltage overhead insulated electric line for UNTRAINED PERSONS and for operating plant or vehicles operated by untrained persons
Nominal phase to phase voltage of high
voltage overhead insulated electric line
Untrained person for the electric line (mm)
Operating plant operated by untrained person for the electric
line (mm)
Vehicle operated by untrained person for the electric line (mm)
Above low voltage, up to 33kV (with consultation with person in control of electric line)
2 000 3 000 900
Above low voltage, up to 33kV (without consultation with person in control of electric line)
3 000 3 000 900
Above 33 kV up to 50 kV
3 000 3 000 2 100
Above 50 kV up to 66 kV
3 000 3 000 2 100
Nominal pole to earth dc voltage of electric line
+/- 25 kV 3 000 3 000 900
+/- 85 kV 3 000 3 000 2 100
93
Part 6: Exclusion zones for high voltage overhead insulated electric line for AUTHORISED AND INSTRUCTED persons and for operating plant and vehicles operated by authorised or instructed persons
Nominal phase to phase voltage of high
voltage overhead insulated electric line
Authorised person or instructed person for
electric line (mm)
Operating plant operated by
authorised person or instructed person for electric line, with
safety observer or another safe system
(mm)
Vehicle operated by authorised person or instructed person for
electric line (mm)
Above low voltage, up to 33kV (with consultation with person in control of electric line)
700 700 700
Above low voltage, up to 33kV (without consultation with person in control of electric line)
700 700 700
Above 33 kV up to 50 kV
750 750 750
Above 50 kV up to 66 kV
1 000 1 000 1 000
Nominal pole to earth dc voltage of electric line
+/- 25 kV 700 700 700
+/- 85 kV 1 000 1 000 1 000
94
Appendix D: Electrical Safety Act 2002
TheActimposeselectricalsafetyobligationsonpersonsfortheelectricalsafetyofothers.Apersoncanhaveanelectricalsafetyobligationinmorethanonecapacity.Forexample,acorporationmayhaveanobligationnotonlyasagenerationentitybutalsoasanemployer,supplierorpersonincontrol.
WheretheWorkplace Health and Safety Act 1995andtheElectrical Safety Act 2002bothapply,theElectrical Safety Act 2002takesprecedence.
ThefollowingaresectionsoftheActwhichhavebeenreferencedinthisCode.Fordetailedinformation,pleaseseetheappropriatesectionoftheAct.
Part 2 Electrical safety obligations
Division 2 Electrical safety obligationsSection29 ObligationofelectricityentitySection30 Obligationofemployerorself-employedpersonSection31 ObligationofdesignerofelectricalequipmentSection32 ObligationofmanufacturerofelectricalequipmentSection33 ObligationofimporterofelectricalequipmentSection34 ObligationofsupplierofelectricalequipmentSection35 Additionalobligationofdesigner,manufacturer,importeror
supplierofelectricalequipmentSection36 Obligationofinstallerofelectricalequipmentorelectrical
installationSection37 Obligationofrepairerofelectricalequipmentorelectrical
installationSection38 ObligationofpersonincontrolofelectricalequipmentSection39 ObligationsofworkerSection40 Obligationsofotherperson
Part 4 Licences
Division 1 Requirements for electrical licencesSection55 Requirementforelectricalworklicence
95
Appendix E: Electrical Safety Regulation 2002
TheRegulationensurestheelectricalsafetyoflicensedelectricalworkers,otherworkers,licensedelectricalcontractors,consumersandthegeneralpublic.ItdoesthisbyprescribinghowobligationssetdownundertheActcanbemet.
ThefollowingaresectionsoftheRegulationwhichhavebeenreferencedinthisCode.Fordetailedinformation,pleaseseetheappropriatesectionoftheRegulation.
Part 2 Electrical workDivision 2 Basic requirements for electrical workSection11 RequirementsforelectricalworkSection12 Requirementsforperformanceoflivework
Division 4 Testing of workSection14 TestingofelectricalequipmentafterelectricalworkSection15 Certificateoftestingandsafety
Division 5 Requirements applying to employers and self-employed personsSection16 Applicationofdiv5Section17 TestingandmaintenanceofsafetyequipmentSection18 Employerorself-employedpersontoensuresuitabilityoftesting
instruments
Division 6 Other requirementsSection19 Electricalequipmentwithseriousdefectnottobeconnectedto
electricitysourceSection20 SignsonswitchesanddisconnectionpointsSection21 Rescueandresuscitationtraining
Division 7 Documents about electrical workSection22 Applicationofdiv7Section23 WhomaysigndocumentsaboutelectricalworkSection24 MisrepresentationsaboutelectricalequipmentorworkSection24A Misrepresentationsaboutlawfulauthoritytocontractforthe
performanceofelectricalwork
Part 4 Working around electrical parts
Division 1 PreliminarySection58 Purposeofpt4
96
Section59 Definitionsforpt4Section61 Meaningofexclusion zoneSection62 Employerorself-employedpersontoensureworkisperformedin
accordancewithrequirementsSection62A Principalcontractorforconstructionworkplace–excavatingand
undergroundelectricalservicesSection62C Employerorself-employedpersonatconstructionworkplace–
excavatingandundergroundelectricalservicesSection62D Employerorself-employedpersonnotatconstructionworkplace
–excavatingandundergroundelectricalservicesSection63 WorkinvolvingdirectcontactwithelectricalpartSection64 Workwithinexclusionzoneforelectricalpart
Division 3 Consultation with persons in control of electrical linesSection64A Requirementtoconsult
Part 5 Electrical installations
Division 1 Performing electrical workSection69 Workinvolvingelectricmotorformingpartofvehicle
Division 5 Workplace electrical installationsSection82 Purposeofdiv5Section83A Meaningofrural industry work
Subdivision 2 All workSection84 Applicationofdiv2Section85 Cordextensionsetsandflexiblecables
Subdivision 3 Construction workSection87 Requirementsforconstructionwiringandelectricalequipment
Subdivision 4 Manufacturing workSection89 DoubleadaptorsandpiggybackplugsprohibitedSection90 SpecifiedelectricalequipmentSection90A Manufacturingwork–safetyswitchSection90B ExemptionforsafetyswitchesSection91 Safetyswitches,includingportablesafetyswitches
Subdivision 5 Service work or office workSection93 SpecifiedelectricalequipmentSection94 Safetyswitches,includingportablesafetyswitches
97
Subdivision 6 Amusement workSection94B DoubleadaptorsandpiggybackplugsprohibitedSection94C SpecifiedelectricalequipmentSection94D AmusementdevicesandamusementridesSection94E Safetyswitches,includingportablesafetyswitches
Subdivision 7 Rural industry workSection94G Requirementsforruralindustrywork
Part 8 Electricity supplyDivision 1 Connection to source of electricitySection149 Electricalinstallationwithseriousdefectnottobeconnectedto
electricitysourceSection150 Electricalinstallationnottobeconnectedtoelectricitysourceif
worknottestedSection151 Electricalinstallationnottobeinitiallyconnectedtoelectricity
sourcewithoutexaminationandtestingSection152 ReconnectionofelectricalinstallationtoelectricitysourceSection154 Licensedelectricalcontractornottoconnectelectricitysource
withoutbeingsatisfiedofcompliancewithActandRegulationSection155 Disconnectionandreconnectionoflowvoltageelectrical
installation
Division 3 TestingSection158 NoticebylicensedelectricalcontractoroftestSection159 CertificateoftestingandcomplianceSection160 Performanceofexaminationortest
Part 12 Incident notification and reportingSection196 Employerorself-employedpersontoadvisechiefexecutiveof
seriouselectricalincidentordangerouselectricaleventSection201 Scenenottobeinterferedwith
Part 13 Miscellaneous provisionsDivision 3 Other mattersSection208 ClimbingpolesofelectricityentityprohibitedSection209 Obligationsofemployeraboutsupervisingtrainingperson
JAG 09/3196
Electrical Safety Office QueenslandTelephone 1300 650 662Website www.justice.qld.gov.au
Electrical Safety Code of Practice 2010 Electrical Work
Department of Justice and Attorney-General
Electrical Safety Office Queensland