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Government of Western AustraliaDepartment of Mines, Industry Regulation and SafetyBuilding and EnergySafe working guidelinesfor electrical workersIssued by the Director of Energy SafetySeptember 2018
PrefaceThis booklet covers basic electrical safety practices to be followed byelectrical workers.It provides advice on achieving and maintaining safe work practices, for thebenefit of the individual worker and for the benefit of others. In particular, itprovides guidelines on providing effective supervision of electrical workerswith varying competencies.Every electrical worker must be constantly vigilant about the dangers involvedin working with electricity. The danger is real.These Guidelines are designed to complement general and specific workplacesafety requirements in the WA Occupational Safety and Health Act 1984, theOccupational Safety and Health Regulations 1996 and the Electricity (Licensing)Regulations 1991. In all instances the requirements of the Act and theRegulations prevail.Every care has been taken to ensure references to legislation, AustralianStandards and other documents in the Guidelines are accurate at the timeof publication.However, amendments to these documents are made from time to timeand the reader should always check to ensure that applicable referencedinformation is current.
Safe working guidelines for electrical workers1
1.ResponsibilitiesGeneralEmployer and employee responsibilities for maintaining workplacesafety are set out in Sections 19 and 20 of the Occupational Safetyand Health Act 1984.Employers have the primary duty of care to maintain a safe workingenvironment for employees by providing information and training, safework procedures, safety equipment and effective supervision.Employees also have a duty of care to ensure their own safety and toavoid any act or omission which adversely affects the safety of othersduring the performance of their work. Employees must cooperate withemployers, follow safe work procedures and use protective equipment.LicensingBoth the employer and the employee have the responsibility to ensurethat the employee has the appropriate current licence, as set out in theElectricity (Licensing) Regulations 1991 (Licensing Regulations), to lawfullyperform electrical work on behalf of the employer, while observing anyrestrictions applicable to the individual licence.Work standardsSupervising electrical workers are responsible for checking and testing allelectrical work carried out by an apprentice or person undergoing trainingto ensure compliance with the Licensing Regulations. (This includescompliance with AS/NZS 3000 Wiring Rules and other technical standardslisted in Schedule 2 of these regulations.)2Safe working guidelines for electrical workers
2.Supervision of electrical workersElectrical accidents and fatalities have occurred when electrical workerswere not adequately supervised. Such incidents are clearly preventable.Effective supervisionWhether you are an employer, supervising electrical worker or an electricalworker under supervision, it is important to understand your obligationsunder the Licensing Regulations.These guidelines will assist in understanding these obligations and forimproving workplace safety.What is effective supervision?The importance of effective supervision is recognised by Regulation 50 ofthe Licensing Regulations. In particular, Regulations 50, 50AA and 50ABprovide detailed requirements for effective supervision of workers for thepurpose of preventing danger to life and property.Effective supervision includes, but is not limited to, the following: ensuring that all workers are licensed to carry out the required work; adequate job planning, risk assessment and risk mitigation; ensuring the supervising electrical worker has the necessary knowledgeand skill levels for the type of work to be undertaken; giving due consideration to the level of training, knowledge and skill ofthe electrical worker(s) who are being supervised; and managing the number and proximity of electrical workers to enable therequired level of oversight and clear lines of communication.The responsibility for providing effective supervision of electrical workersrests with employers and supervising electrical workers. In deciding onthe appropriate level of supervision for an electrical worker on a particularscope of work or task, the supervising electrical worker must consider allrelevant factors including, but not limited to, the following.(1) The type of workVariations in the work environment, whether related directly toelectricity supply or not, present many different circumstances andrisks. Supervising electrical workers must assess these risks whendetermining safety requirements for the job at hand and the level ofsupervision appropriate for the electrical worker. These include, but arenot limited to: work type and location e.g. residential, commercial, mining, etc.;Safe working guidelines for electrical workers3
new construction or alteration/addition to an existing installation; or proximity to energised electrical equipment on the site and thevoltage and maximum fault current of that equipment.(2) Knowledge and skills of the employeeThe supervising electrical worker must assess the technical knowledgeand practical skills of the electrical worker using information availablefrom both academic and on-the-job training records.The level of supervision needed for safe working must reflect thisassessment.(3) Competence of the supervising electrical workerEmployers must ensure that supervising electrical workers have thenecessary competencies to provide effective supervision of anotherelectrical worker, including: being licensed to carry outthe electrical work withoutsupervision; appropriate technicalknowledge, skills andexperience in regard tothe particular work to beperformed; effective communicationskills; and preferably, formal training insupervision of other workers.Levels of supervision for apprenticesThree different levels of supervision are defined in detail in Regulation 49Dand briefly summarised below:(1) Direct supervision“Direct” supervision applies where the apprentice requires constantguidance and monitoring by the supervising electrical worker to ensurethe work task is carried out safely and correctly.The supervising electrical worker must remain on the same work siteas, and in close proximity to, the apprentice.4Safe working guidelines for electrical workers
(2) General supervision“General” supervision applies where the apprentice requires periodicguidance and monitoring to ensure the work task is carried out safelyand correctly.The supervising electrical worker must remain on the same worksite as the apprentice and be readily available to provide guidanceand assistance.(3) Broad supervision“Broad” supervision applies wherethe apprentice does not requireongoing guidance and monitoringwhile performing familiar tasks.The supervising electrical workerdoes not need to remain on thesame site as the apprentice butmust, as a minimum, attendthe work daily to provide initialinstruction and to verify theelectrical work has been carriedout safely and correctly.Determining appropriate levels of supervision for apprenticesThe level of guidance required by an apprentice can be expected todiminish gradually over the course of the apprenticeship, as increasingcompetence is attained and demonstrated by the apprentice.However, the appropriate level should be applied at any time based on thesupervising electrical worker’s assessment of the apprentice’s competenceto perform each task. For example, a task being performed for the firsttime or in an unfamiliar environment in the final year of training may initiallyrequire direct supervision for that particular task.The following table provides guidance to employers and supervisingelectrical workers on appropriate minimum levels of supervision ofapprentices at different stages of training and for different work types(de-energised only), subject to assessment by the supervisingelectrical worker.Safe working guidelines for electrical workers5
Type of work(de-energised vision levelNew electrical installations(not connected to electricity supply)1st2nd3rd4th or finalGeneralGeneralBroadBroadMaintenance, alterations and additionsto existing electrical installations(isolated and proven de-energised bysupervising electrical worker)1st2nd3rd4th or finalDirectGeneralGeneralBroadWorkshop assembly and maintenanceof electrical equipment(not connected to electricity supply)1st2nd3rd4th or finalGeneralGeneralBroadBroadTag and lockout procedure on deenergised installations and equipment(isolated and proven de-energised bysupervising electrical worker)1st2nd3rd4th or finalDirectGeneralGeneralBroadTesting and fault-finding on deenergised installations and equipment(not connected to electricity supply orisolated and proven de-energised bysupervising electrical worker)1st2nd3rd4th or finalDirectDirectGeneralGeneralThe levels of supervision applied in practice may vary from therecommended minimum levels subject to a diligent assessment bythe supervising electrical worker of the nature of the work, the specificcircumstances and risks, and the competence of the apprentice toperform the task.The following flowchart illustrates the appropriate steps for the supervisingelectrical worker to carry out such an assessment.6Safe working guidelines for electrical workers
Assessing the appropriate level of supervision for an apprentice(de-energised work only)StartApplysuppervisionas per WAOSH Acts19(1)(b)NoIs the work‘electrical work”?*”First stage”includes:– First 6 months– New orunfamiliar worktype/environmentYesYesIs the apprentice inthe first stage of training?NoAccess the ability of apprentice* tocarry out the taskNo*Consider (but notlimit to):– Installation typeand locatione.g. residential,commercial,minesite,workshop– Technicaldifferences inequipment e.g.switchboarddesign/construction– Climate extremesHas apprentice carried outthis or similar task before?YesNoHas apprentice carried out similartasks correctly and often enough tojustify less than Direct supervision?YesHas apprentice carried outsimilar work competently on enoughoccassions to justify moving toBoard supervision only?YesNoSupervising electricalworker to applyDIRECTsupervision to apprenticeSupervising electricalworker to applyGENERALsupervision to apprenticeSupervising electricalworker to applyBROADsupervision to apprenticeSafe working guidelines for electrical workers7
De-energisation of equipment – apprentice to verifyFrom the start of workplace training, apprentices should, after deenergisation of the circuit or equipment by the supervising electrical workerand prior to commencing work, always: participate in the tag and lockout procedure by applying personaltags and locks; and ‘TEST BEFORE YOU TOUCH’ – personally verify, by electricaltesting, that the circuit or equipment is de-energised.The appropriate level of supervision for an apprentice performing this taskis shown in the previous table.Supervision of apprentices and restrictions for work on or nearenergised equipmentWork on or near energised electrical circuits and equipment by anyelectrical worker is prohibited by the Licensing Regulations except incertain prescribed circumstances and subject to performing a detailed riskassessment and formal documentation of a safe work method statement.The Licensing Regulations permit an electrical apprentice to carry outisolation, testing and fault finding on energised equipment in the followingstrictly limited circumstances, in combination:8 only in the final year of training; only if assessed by the supervising electrical worker as beingcompetent to perform the task safely; andSafe working guidelines for electrical workers
only under direct supervision, with the supervising electrical worker inclose proximity to the apprentice for the duration of the task.In all cases, the supervising electrical worker is responsible for therisk assessment, safe work method statement, instruction and directsupervision of the apprentice and final verification and testing of the work.Section 6 of these Guidelines provides further informationabout where and how work, by any person, on or near energisedelectrical equipment is permitted.Before apprentices commence workBefore an apprentice commences any electrical work the supervisingelectrical worker must: be confident that the apprentice is fit for work; ensure there are no exposed live parts and the electrical equipment isde-energised and safe to be worked on or near; clearly instruct the apprentice on which tasks he/she is expectedto do and which ones he/she must not be doing until he/she isinstructed on how to do the tasks. Confirm that the apprenticeunderstands the work instructions; advise the apprentice which level of supervision applies to the workand confirm the apprentice understands the limitations this appliesto the work; ensure that the apprentice is equipped with the necessary personalprotective equipment (PPE) and tools and understands how to usethem correctly; and where the equipment has been de-energised to allow work to be carriedout on or near, ensure that the apprentice: has applied their personal lock and danger tag at the isolationpoint(s); and has verified by an electrical test that the equipment is de-energised– TEST BEFORE YOU TOUCH.Safe working guidelines for electrical workers9
3.Dangers of working with electricityElectrical risksThe most common electrical risks and causes of injury are: Electric shock causing injury or death. Burns from arcing, explosion or fire. Falls from ladders, scaffolds or elevated work platforms (EWPs) as adirect consequence of an electric shock. Poisoning from toxic gases causing illness or death. Fire resulting from an electrical fault.It only requires a very small failure of a work practice, such as a slip with ascrewdriver or a dropped tool, for such accidents to occur.Electric shockAll electric shocks must be avoidedAll electric shocks are potentially fatalMinor shocks could have resulted in death or injury hadcircumstances been only slightly different.Electric shock is the effect produced on the body, particularlythe nervous system, by an electrical current. The effect variesdepending upon the magnitude, path and frequency of the currentand the duration of contact. (Even the briefest contact withelectricity can have serious consequences.)If the current magnitude is within a certain range and its pathtraverses the heart region, the normal rhythm of the heart can beinterrupted. In this state, known as ventricular fibrillation, the heartcontracts randomly and cannot maintain blood circulation. Returnto normal rhythm rarely occurs spontaneously and if the conditionpersists for more than a few minutes, the result is almost certainto be fatal.Electric shock may also stop the heart completely and/or thevictim’s breathing.10Safe working guidelines for electrical workers
The likely physiological effects of electric shock on a healthy adult are illustratedin the following two figures1, for variations in the amount of electric currentflowing through the body and time of exposure:ZoneEffects of electric shock on the human body1Perception possible but usually no ‘startled’ reaction2Perception and involuntary muscular contractions likely but usuallyno harmful effectsStrong involuntary muscular contractions.Difficulty in breathing.3Reversible disturbances of heart function.Immobilisation may occur.Effects increasing with current magnitude.Usually no internal organ damage expected.4561Patho-physiological effectsmay occur: cardiac arrest breathing stops burns internal organ damageInjuries may result in DEATH.Probability of ventricular fibrillationup to about 5 per centProbability of ventricular fibrillationup to about 50 per centProbability of ventricular fibrillationabove 50 per centAdapted from AS/NZS 60479.1:2010 ‘Effects of current on human beings and livestock –General aspects’Safe working guidelines for electrical workers11
10 sec5 secZone 1Zone 2Zone 3 4 5Zone 6DURATION OF CURRENT FLOW2 sec1 sec500 ms200 ms100 ms50 ms20 ms10 ms0.1 mA 0.2 mA0.5 mA1 mA2 mA5 mABODY CURRENT10 mA 20 mA50 mA 100 mA 200 mA500 mA1 amp2 amp5 amp 10 ampSee noteNote: The standard 30 mA RCD operates within 300 milliseconds for a circuitcurrent imbalance of 30 mA, providing effective protection against potentiallylethal high body currents (Zones 3, 4, 5 and 6).BurnsElectrical arcing occurs when electrical insulation betweenconductors can no longer withstand the applied voltage or isbridged by conductive material.Electricity flashovers/arcs can produce extreme temperatures, veryhigh forces and toxic gases, and persons in the vicinity commonlysuffer severe burns, permanent disfigurement or fatal injuries.The risk of injury from arcing or explosion is extreme when highfault currents are present. This typically applies to low voltagecircuits close to transformers or switchboards, where the electricalprotection may only detect and interrupt an arcing fault slowly ornot at all.Arcing faults can occur at any time for a variety of reasons.However, they generally occur as a result of an external influencewhich, typically, may involve the actions of an electrical worker, forexample during maintenance or energisation of equipment.12Safe working guidelines for electrical workers
An arc flash hazard is effectively eliminated if work isundertaken on a completely de-energised switchboardand no switching operations are performed manually.FallsFalls from ladders, scaffolds or other elevated work platforms canoccur as a direct consequence of an electric shock or arc blast,potentially resulting in serious injury or death.PoisoningBurning and arcing associated with electrical equipment mayrelease various harmful gases and contaminants. Inhalation ofthese dangerous products may cause short term or chronic illnessor result in death from suffocation.FireElectrical workers may not be the only ones at risk. Faultyelectrical equipment and poor standards of work can lead to firesthat may cause injury or death to persons using the installationand property loss.Safe working guidelines for electrical workers13
4.Safe working practicesBefore starting work Plan the job carefully, including a risk assessment and isolationrequirements. Ensure all workers have the appropriate PPE and its condition issatisfactory. PPE will provide only limited protection from electricalrisks such as electric shock, arc flash and arc blast. If work is in the vicinity of energised electrical equipment and ifrequired by the risk assessment, ensure workers have a low voltage(LV) rescue kit. Check if the upstream electrical protection has a maintenance settingthat enables an immediate circuit trip if any fault occurs. Confirm permission to isolate (comply with any access or vicinitypermit system applicable to the site). Isolate the electrical equipment or circuit. Secure the isolation by fitting personal locks and “Danger” or “Out ofService” tags (as applicable) on the isolating device(s). Erect safety barriers where required. Cover adjacent live apparatus with insulating barriers where required todo so by the risk assessment. TEST BEFORE YOU TOUCH – Always test for no voltage beforestarting work (check test instruments before and after every test). Ensure test instruments are fit for purpose and adequately rated (e.g.Category IV etc.). Use the correct earthing equipment. Start work only when authorised to do so.If in doubt about anything, seek confirmation beforestarting work.14Safe working guidelines for electrical workers
When working Always wear the PPE required for the work. Use only the correct tools and safetyequipment for the work. Never put yourself or others at risk. Use safety observers where required. Never rely on your memory about workconditions – if unsure about anything, checkvisually or re-test. Disconnect conductors in order – the active first, the neutral secondand the earth last. Connect conductors in order – the earth first, then the neutral and theactive last. Check the isolation points and re-test before resuming work after abreak – TEST BEFORE YOU TOUCH.On completion of work Check that tools are not left on or in the job. Remove personal earthing equipment (where applicable). Check that the work is complete and has been tested. Notify all personnel directly involved in the work that the equipment willbe energised. Remove your “Danger” or “Out of Service” tags and locks. Check all “Danger” tags, “Out of Service” tags, earths and locks havebeen removed by other workers. Remove and store all safety barriers and other equipment. Relinquish your work permit (if relevant). Energise equipment and confirm correct operation, includingrestoration of normal electrical protection settings (if applicable).Safe working guidelines for electrical workers15
Safety practices Keep a well maintained first aid kit handy. Know the electric shock and resuscitation procedure. Know where fire extinguishers are located and how to operate them. Know the correct type of fire extinguisher for the various types of fires. Keep your work place clean and orderly. When working near energised electrical equipment, have an LV rescuekit for immediate use if required. Report all electrical accidents to your employer (who must report theaccident immediately to the relevant network operator).Tools16 Use the correct tools for the job at hand. Regularly check, clean and maintain all tools and equipment andrecertify (where applicable). Use residual current devices (RCDs) when using plug-in electric tools. Use insulated ladders. Use approved safety harnesses and other equipment. Use non-conducting tape measures when working on or nearelectrical equipment.Safe working guidelines for electrical workers
5.Electrical isolation and de-energisation of equipmentBefore commencing any electrical work, the circuits or equipment to beworked on must be disconnected from all sources of electricity supply, theisolation points physically secured to prevent inadvertent re-energisation,and proven to be de-energised.Principles and safe practices for the effective de-energisation of electricalcircuits and equipment are provided in Building and Energy’s “Code ofPractice for Persons working on or near energised electrical installations”2.The key steps are summarised below for reference.Essential steps for effective de-energisation of equipmentEquipment is energisedActions required1. Isolate2. Secure3. TestEquipment is de-energised2Identify and disconnect all sourcesof electricity: switch of isolator/circuitbreaker; and remove fuses or othercomponents.Secure the isolation: lock isolator/circuit breaker in“OFF” position; and fit danger tag at isolation point.Test that equipment is deenergised: check test instrument withknown voltage source; then test equipment isde-energised; then re-check test instrument withsame voltage source.The associated national technical standard is AS/NZS 4836:2011 – Safe working on or near lowvoltage electrical installations and equipmentSafe working guidelines for electrical workers17
Securing the isolationLocksWhere a facility exists to lock a switch in the “OFF” position, it must beused. Where a facility does not exist, a portable lock out device (“lock dog”)must be fitted to the switch mechanism to prevent closing.Locks are for the safety of personnel and: they must be uniquely keyed so that they can be fitted and removedonly by the person owning the lock; all persons involved in carrying out the work must fit their own lock atthe same isolation point(s). This may require the use of a multi-locksecurity device; they must be clearly labelled (with a personal identification tag orDanger tag) to identify the owner and the nature of the electrical workbeing undertaken; and they must be removed upon completion of work or at the end of the shift(if the work will be continued by others, who must fit their own locks).Danger tagsA Danger tag on an item of equipment is a warning to all persons that theequipment must not be operated, as lives may be placed in danger.Danger tags are for the safety of personnel and: they must be fitted andremoved only by the personwho signed the tag; all persons involved incarrying out the work must fittheir own Danger tag at thesame isolation point(s); and 18they must be attached in aprominent position at eachisolation point;they must be removed uponcompletion of the work orat the end of the shift (if thework will be continued byothers, who must fit theirown Danger tags).Safe working guidelines for electrical workersDANGERDANGERDO NOTOPERATETHIS DEVICEOR REMOVETHIS TAGDO NOTOPERATEMy Life May be EndangeredThis tag MUST NOT be removedexcept by the personnamed above or,as provided under anapproved procedureSEE OTHER SIDEName:Company:Contact Details:Date:This tag MUST NOT be removedexcept by the personnamed above or,as provided under anapproved procedure
Out of Service tagsThis tag is used to identify appliances or equipment that are out ofoperation for repairs or alterations or are still in the process of beinginstalled. While an Out of Service tag is fitted, the appliance or equipmentmust not be operated.Out of Service tags are for thesafety of personnel and securityof equipment and must be: attached in a prominentposition at the point ofisolation of the applianceor equipment that is beingworked on; andfitted and removed only byauthorised persons.OUT OFSERVICEOUT OFSERVICEDO NOT USEOR OPERATEDO NOT USEOR OPERATEPlaced by:NAME:ORGANISATION:DATE:REASON:This TagMUST NOTbe removedunlessauthorised bya competentpersonSafe working guidelines for electrical workers19
6.Work on or near energised electrical equipmentWork on or near energised electrical equipment is generallyprohibitedElectrical installing work must not be carried out on or near energisedequipment except in the circumstances and manner as defined inRegulation 55 of the Licensing Regulations.These exceptions do not apply to work carried out by, or on behalf of, anetwork operator on a network, including service apparatus.The exceptions and approach to restricted work on energised electricalequipment are summarised in the following sections for ease of reference.The limited circumstances in which energised work is permittedand the strict precautions that are required to maintain safeworking conditions are prescribed in the: Occupational Safety and Health Regulations 1996; (OSHRegulations) Electrical (Licensing) Regulations 1991; Code of Practice for Persons working on or near energisedelectrical installations (published by Building and Energy); and The Commission for Occupational Safety and Health’s Guidancenote - Work in roof spaces 2018.ExceptionsWork on or near energised electrical equipment may only be undertakenwhere the supervising electrical worker has determined it is the onlypractical option because:(1) it is necessary that the electrical equipment to be worked on isenergised in order for the work to be carried out effectively (e.g. testing,commissioning, switching, fault-finding);(2) de-energising that part of the installation would put the health andsafety of a person at significant risk (e.g. it may be necessary for lifesaving equipment to remain energised and operating while electricalwork is carried out on the premises); and(3) a risk assessment demonstrates that the risks can be reduced to aminimum practical level to enable the work to be performed safely.Note: Loss of production by itself is not a satisfactory reason for workingon energised equipment.20Safe working guidelines for electrical workers
Where work on or near energised equipment is the only optionThe required approach to carrying out live electrical work is set out in: Regulation 55 of the Licensing Regulations; and Regulation 3.143 of the Occupational Safety and HealthRegulations 1996.In summary, the regulations require that:(1) A comprehensive risk assessment must be conducted by a competentperson, who may be the supervising electrical worker. The riskassessment must consider, but not be limited to: the fault level; specific arc flash containment within the design of the equipment; likely direction of an arc blast; and adequacy of electrical protection settings.(2) The identified risks and control measures implemented must bedocumented in a written “safe work method statement” and a recordkept for at least two years after the work is completed.(3) The work must be undertaken only: in accordance with the pre-determined work method; and by competent persons who have the necessary tools, equipmentand PPE for the work.Further detailed guidance is provided in the “Code of Practice for Personsworking on or near energised electrical installations”.Work in the vicinity of energised electrical equipmentIn some circumstances, the risks associated with undertaking electricalwork near energised equipment can be equivalent to those associated withwork on energised electrical equipment.Detailed guidance is provided in the “Code of practice for Persons workingon or near energised electrical installations”, where the term “near” has themeaning given in Regulation 54A(2) (of the Licensing Regulations):“ a person carries out electrical work near an energised part of anelectrical installation if, the person may make contact, directly orindirectly (including with a thing used or controlled by the person), withan uninsulated energised part of the electrical installation.”Safe working guidelines for electrical workers21
A risk assessment must be performed by a competent person to determinethe risk level associated with working near energised electrical equipmentand appropriate risk control measures must be implemented anddocumented in the safe work method statement.Work in roof spacesThe OSH Regulations generall
Government of Western Australia Department of Mines, Industry Regulation and Safety Building and Energy Safe working guidelines for electrical workers Issued by the Director of Energy Safety September 2018. Preface This booklet c
