EV High-Voltage Workshop Repair SWMS
High-voltage electric vehicle workshop work — HV battery isolation, service disconnect lockout, contactor-open verification, insulation resistance testing, HV component R&R, battery thermal monitoring during work, post-work re-energisation.
SWMS variants reference your state’s WHS legislation. Instant download after payment.
Electric vehicle high-voltage workshop repair covers service and repair work on the high-voltage system of battery-electric and hybrid vehicles in an automotive workshop — HV battery isolation, service-disconnect lockout, contactor-open verification, insulation-resistance testing, removal and replacement of HV components, battery thermal monitoring during the work, and controlled re-energisation. Modern EV traction systems operate at DC voltages well above the 60 V threshold at which a system is treated as high voltage in the automotive context, commonly 400 V and increasingly 800 V on newer platforms. At these voltages a single inadvertent contact can be fatal, and the stored energy in a traction battery is sufficient to sustain a destructive arc, so the work is treated as High-Risk Construction Work on the ground that it is performed on or near an energised electrical installation.
The defining control is positive isolation: the HV system must be shut down, the service disconnect removed and locked out, and the absence of voltage proven at the point of work before any HV component is touched. Unlike a fixed installation, an EV traction battery cannot be switched off — it remains a live source even with the service disconnect removed — so the work relies on isolating the battery from the drivetrain, verifying the contactors are open, and confirming the capacitors in the inverter have discharged before contact. The work is governed by the safe-system-of-work principles in Managing Electrical Risks in the Workplace and the live-work and testing requirements of AS/NZS 4836, with the vehicle manufacturer's HV service procedure as the controlling technical reference.
This SWMS is jurisdiction-neutral within Australia and written to the model WHS framework. Victoria operates under the Occupational Health and Safety Act 2004 and OHS Regulations 2017 — check the VIC-specific variant for the local equivalents of the duties and codes cited here.
Hazards identified
12 hazards covered, sorted by priority.
Fatal electric shock; DC contact across the chest can cause cardiac arrest, and the stored energy is sufficient to cause deep-tissue burns at the contact points.
Severe arc burns and blast injury; a DC arc at traction-battery voltage is self-sustaining and can ignite clothing and nearby combustibles.
Electric shock when a capacitor that has not discharged is contacted, even though the service disconnect has been removed and the contactors are open.
Electrocution if the HV system is re-energised, a second technician closes the contactors, or a high-voltage component is reconnected during work.
Fire and toxic vent-gas release; a battery damaged by collision or internal fault can enter runaway during diagnosis or removal, producing flammable and toxic gas in the workshop.
Crush or impact injury from suspended components, sprung assemblies, or a vehicle moving on a hoist during high-voltage component removal.
Musculoskeletal injury — back and shoulder injury — from lifting traction battery packs that can weigh several hundred kilograms without mechanical aids.
Struck-by or crush injury if a vehicle is inadvertently driven, rolls, or falls from a hoist while HV work is in progress.
Chemical burns or irritation to skin, eyes, and airway from contact with battery electrolyte or HV-battery coolant during component removal.
Electric shock or arc when a tester or insulated tool not rated for the system voltage fails in service during isolation or testing.
Inadvertent contact with a live HV conductor mistaken for a low-voltage one; HV cabling is orange but can be obscured or non-standard on imported vehicles.
An isolation step missed or performed out of order, leaving the system unexpectedly live at the point of work.
Control measures
Hierarchy-of-controls order: elimination → substitution → isolation → engineering → administrative → PPE.
- 1Eliminate live exposure by fully shutting down the HV system, removing the service disconnect (manual service disconnect / HV interlock), and locking it out under personal control before any HV work begins, following the vehicle manufacturer's documented HV service procedure.
- 2Prove the absence of voltage at the point of work with an HV tester rated and proven for the system voltage to AS/NZS 4836 — test-prove-test — and confirm the contactors are open and the inverter DC-link capacitors have discharged before contact.
- 3Apply a one-worker-one-lock isolation regime with a lock-out tag-out on the service disconnect, so the HV system cannot be re-energised by another person while work is in progress.
- 4Wait the manufacturer-specified capacitor discharge time after isolation and verify discharge by measurement before touching any HV component, never relying on time alone.
- 5Establish a designated HV work area with barriers and signage, restricted to a competent HV technician, with a second competent person available for rescue and a non-conductive rescue hook within reach.
- 6Assess every traction battery for damage or fault before work, and quarantine and follow the manufacturer's damaged-battery procedure for any pack showing signs of collision damage, swelling, heat, or fault codes that indicate runaway risk.
- 7Support the vehicle on a rated hoist with the wheels chocked and the vehicle immobilised, and release stored mechanical and pneumatic energy before removing drivetrain components.
- 8Use mechanical lifting aids — a battery lift table or jack rated for the pack weight — and team-lift limits for heavy HV battery and component handling.
- 9Manage battery electrolyte and HV coolant as hazardous substances with the relevant safe handling, containment, and PPE per the safety data sheet.
- 10Use only insulated tools and HV test equipment rated for the system voltage, inspected before use, and within calibration, and use orange HV cabling identification consistently to prevent misidentification.
- 11Brief the isolation sequence as a documented checklist signed off before HV contact, and manage fatigue and distraction with defined work periods so the sequence is not rushed or interrupted.
- 12Provide PPE as the final layer — insulating gloves rated to the system voltage with leather over-protectors, arc-rated clothing and face protection matched to the calculated DC incident energy, and eye and skin protection for electrolyte and coolant — inspected and fit-checked before each task.
- 13Verify the technician holds the relevant HV/EV competency (de-energising, isolation, and HV component repair) in addition to the trade qualification, and brief every worker on the SWMS and the manufacturer's procedure before work starts.
Applicable Codes of Practice
Becomes legally binding under Section 26A of the WHS Act from 1 July 2026. Sets the safe-system-of-work baseline for de-energising, isolating, and proving de-energised an HV traction system before work, and points to AS/NZS 4836 for testing and live-work principles.
Safe working on or near low-voltage and high-voltage electrical installations and equipment. Provides the test-prove-test methodology, isolation verification, and rated-equipment requirements applied to proving the EV HV system de-energised.
Electric vehicle operations — provides Australian guidance on safe work practices for electric vehicle servicing, including HV isolation and the competencies required for HV work.
Becomes legally binding under Section 26A from 1 July 2026. Governs the safe use of vehicle hoists and battery lifting equipment, including rating, inspection, and immobilisation of the vehicle during work.
Becomes legally binding under Section 26A from 1 July 2026. Governs the handling of battery electrolyte and HV coolant and the response to vent gas from a battery entering thermal runaway in the workshop.
Governs the workshop's own fixed electrical installation, including the supply to EV charging and diagnostic equipment used during the repair.
High-Risk Construction Work triggered
EV traction systems operate at DC voltages of 400-800 V — far above the 60 V threshold at which automotive systems are treated as high voltage. An EV traction battery cannot be switched off and remains a live source during isolation and testing, so the repair is work on or near an energised electrical installation under WHS Regulation s. 291.
Failure to prepare a SWMS before High-Risk Construction Work commences is a contravention of WHS Regulation s. 291. Category 2 offences under WHS Act s. 32 — where a duty breach exposes a person to a risk of death or serious injury without proof of recklessness — attract substantial monetary penalties for body corporates and individual duty holders; refer to the current SafeWork NSW penalty schedule for the NSW-indexed 2025-26 figures. Category 1 reckless-conduct offences under WHS Act s. 31 attract up to approximately $10.42 million for a body corporate, $2.17 million for an individual PCBU or officer, and $1.04 million for an individual worker, with up to 10 years' imprisonment (NSW-indexed at 1 July 2025). VIC maximum penalties under the Occupational Health and Safety Act 2004 differ in structure and amount and are set at VIC variant-generation time.
Who this is for
- →Independent automotive workshops adding electric and hybrid vehicle servicing to their service offering.
- →Franchised dealership service departments performing HV battery and drivetrain repair under manufacturer procedures.
- →Mobile EV technicians who isolate and repair HV systems at customer or fleet sites.
- →Fleet maintenance operations servicing electric vans, buses, or light commercials in-house.
- →Auto-electrical businesses extending HV competency to traction-battery diagnosis and component replacement.
What you receive
- ✓Editable Microsoft Word .docx — open in Word or Google Docs, drop in your company logo and ABN.
- ✓State-specific variant matched to the jurisdiction selected at checkout (NSW, VIC, QLD, SA, WA, TAS, NT, or ACT).
- ✓All 12 hazards risk-assessed with inherent and residual ratings against a documented control set.
- ✓Isolation and testing controls referenced to AS/NZS 4836, AS 5732, and the model codes of practice.
- ✓Reg 291 HRCW breakdown showing the energised-installation trigger and the legal duty to prepare the SWMS first.
- ✓CIH-reviewed content written to be defended in front of a workshop auditor or a SafeWork inspector.
- ✓Instant download on payment, with a re-download window so you can retrieve the file again if needed.
- ✓Sign-on register and review-log structure ready for site-specific completion by the PCBU.
Worked example
A family-owned automotive workshop in Brisbane decides to take on electric and hybrid servicing as more EVs enter its customer base. The principal technician completes the HV/EV de-energising and component-repair competency, and the business invests in rated HV gloves, an HV-rated tester, and a battery lift table. Before the first HV job — a coolant leak on the traction battery of a 400 V battery-electric hatchback — the workshop adapts this SWMS, selecting the QLD variant which references the Electrical Safety Act 2002 and the state framework. The technician follows the manufacturer's HV service procedure: the vehicle is supported on a rated hoist and immobilised, the HV system is shut down, the manual service disconnect is removed and locked out under the technician's personal lock, and the absence of voltage is proven at the point of work with a rated tester using test-prove-test to AS/NZS 4836. The manufacturer's capacitor-discharge time is observed and discharge is verified by measurement before any HV connector is touched. A second competent person is present with a rescue hook for the duration of the HV work. The coolant is managed as a hazardous substance per its safety data sheet. The component is replaced, the system is reassembled, and re-energisation is performed as a controlled step with the work area clear. The job is completed without an HV incident, and the signed SWMS, isolation checklist, and competency records are retained on the job file in case of an insurer or regulator query.
Related legislation
- Work Health and Safety Act 2011 (NSW) — Sections 19 (primary duty of care), 31 (Category 1 offence), 32 (Category 2 offence)
- Work Health and Safety Regulation 2017 (NSW) — Sections 291 (HRCW definition), 299 (SWMS), 140-165 (electrical risks and work)
- AS/NZS 4836:2023 — Safe working on or near low-voltage and high-voltage electrical installations and equipment
- AS 5732:2022 — Electric vehicle operations (safe work practices for EV servicing)
- AS/NZS 3000:2018 — Electrical installations (Wiring Rules) for the workshop fixed installation
Frequently asked questions
At what voltage does EV work become high-voltage work?
In the automotive context a system is treated as high voltage above 60 V DC, and EV traction systems run at 400 V or 800 V. At these voltages a single inadvertent contact can be fatal and the stored energy can sustain a destructive arc, which is why the work is High-Risk Construction Work and requires positive isolation and proving de-energised before any HV component is touched.
Can the traction battery be switched off before work?
No — a traction battery cannot be switched off and remains a live source even with the service disconnect removed. The safe system of work isolates the battery from the drivetrain by removing and locking out the service disconnect, verifies the contactors are open, and confirms the inverter capacitors have discharged before contact. The SWMS sets out this sequence as a signed checklist.
What competency does the technician need beyond a trade qualification?
An HV/EV competency covering de-energising, isolation, and HV component repair is required in addition to the automotive trade qualification. The SWMS requires this competency to be verified before HV work, consistent with AS 5732 guidance and the manufacturer's service procedure, because the isolation and testing steps demand specific HV skills and rated equipment.
What happens if the battery is damaged or shows fault codes?
A damaged or faulty battery is quarantined and handled under the manufacturer's damaged-battery procedure, because it can enter thermal runaway and release flammable, toxic vent gas during diagnosis or removal. The SWMS treats damaged-battery handling as a distinct hazard with controls separate from routine HV repair, and prohibits work on a pack showing collision damage, swelling, or heat until the manufacturer's procedure is followed.
Does this SWMS cover mobile EV repair at a customer site?
Yes — the safe system of work applies whether the repair is in a workshop or at a customer or fleet site, with the same isolation, proving, and rescue arrangements. For mobile work you adapt the SWMS to the site conditions (work area control, second person, and emergency access) and select the relevant state variant. The HV isolation and testing controls do not change with location.