High-Voltage Electrical Injuries: What to Do When Things Go Wrong on Site

High-voltage electrical injuries are among the most severe and unpredictable workplace incidents in Australia. Unlike low-voltage contact, exposure to high-voltage current — typically defined as anything above 1,000 volts AC or 1,500 volts DC — can cause catastrophic internal injury, immediate cardiac arrest, and severe burns with very little warning. For electrical workers, lineworkers, and site managers on construction projects, knowing what to do in those first critical minutes can determine the outcome.

The challenge with high-voltage incidents is that the severity is rarely visible. A worker may be thrown clear of the source and appear conscious, but still be at immediate risk of delayed cardiac arrest or organ damage from the current pathway through their body. Getting the response right — and fast — matters enormously.

Why High-Voltage Injuries Are Different

The body responds to electrical current based on two main variables: the level of voltage and the path the current takes through the body. High-voltage current does not just burn at entry and exit points — it can cause a range of serious internal injuries.

Ventricular fibrillation is a disruption of the heart’s electrical system that causes it to quiver rather than pump. This is the most common cause of death in electrical incidents. Without immediate CPR and defibrillation, it is fatal within minutes.

Deep tissue damage is common with high-voltage exposure. The current can destroy muscle, nerve, and connective tissue deep inside the body while leaving minimal external signs. Breakdown of muscle tissue can cause acute kidney failure in the hours following an incident.

Blast and arc injuries can also occur. High-voltage contact can generate arc temperatures exceeding 20,000°C. The resulting pressure wave can throw workers several metres, causing blunt force trauma in addition to burns and electrical injury.

Respiratory arrest can result when current passes through the chest wall and paralyses the respiratory muscles, causing breathing to stop even when the heart is still beating.

These compounding injury mechanisms mean that a worker involved in a high-voltage incident should always be treated as critically injured until assessed by qualified medical personnel.

Scene Safety: The Non-Negotiable First Step

With high-voltage incidents, the single most important rule for bystanders and first aiders is this: do not approach until the source has been de-energised and confirmed safe by a licensed electrical worker.

High-voltage electricity can arc across air gaps of several metres, meaning a rescuer approaching a still-energised casualty may be struck without making direct contact. Ground gradients — where electrical current spreads through the earth after contact — can also electrocute a rescuer who steps into the affected zone.

The immediate steps when a high-voltage incident is suspected:

First, do not approach. Keep bystanders well clear — a minimum of 8 metres is recommended for high-voltage incidents involving overhead infrastructure.

Second, call 000 immediately. Give the location, describe the incident, and state that a high-voltage electrical injury is suspected.

Third, if the incident involves network infrastructure (overhead power lines, substations, or transformers), contact the relevant distribution network service provider to arrange emergency isolation. In Victoria, this is United Energy, Powercor, CitiPower, AusNet Services, or Jemena, depending on the area.

Fourth, wait for confirmation from a qualified electrical worker that the power is isolated before approaching the casualty.

First Aid Response Once the Scene Is Safe

Once electrical isolation has been confirmed, approach the casualty and begin primary assessment following the Australian Resuscitation Council (ARC) DRSABCD action plan.

Check for responsiveness. Tap the casualty’s shoulders and call out to them. If unresponsive, assume cardiac arrest until proven otherwise.

Check for normal breathing. Look for chest rise, listen, and feel for breath for no more than 10 seconds. Agonal breathing — irregular gasping — is not normal breathing. Begin CPR.

Begin CPR if needed. Follow ARC guidelines: 30 chest compressions at a rate of 100–120 per minute, followed by 2 rescue breaths. If an Automated External Defibrillator (AED) is available, apply it as soon as possible and follow the prompts. Do not stop CPR until paramedics take over or the casualty shows clear signs of life.

Manage burns. If the casualty is breathing and responsive, treat any visible burns by cooling them under cool running water for at least 20 minutes. Do not remove clothing stuck to the wound. Cover loosely with a clean, non-fluffy dressing or cling wrap.

Treat for shock. Keep the casualty still, warm, and calm. Do not give food or drink. Monitor breathing and consciousness until paramedics arrive.

Minimise movement. High-voltage incidents involving a blast or fall can cause spinal injuries. Unless the casualty is in immediate danger, avoid moving them until emergency services arrive.

Reporting Obligations Under WorkSafe Victoria

Under the Occupational Health and Safety Act 2004 (Vic), a high-voltage electrical incident that results in injury, near-miss, or plant damage must be reported to WorkSafe Victoria. For serious injuries — defined as those requiring immediate treatment as an in-patient in a hospital — notification must occur immediately, followed by a written report within 48 hours.

Safe Work Australia’s Model Work Health and Safety Regulations also require that the incident site be preserved until a WorkSafe inspector has attended or given clearance, unless preservation creates further risk. Do not alter, dismantle, or remove any equipment involved in the incident without clearance.

Failure to report is an offence under Victorian OHS law and can result in significant penalties for both individuals and organisations.

First Aid Training Requirements for Electrical Contractors

All electrical contractors operating in Victoria are required to have adequate first aid coverage on site under the Occupational Health and Safety Regulations 2017 (Vic). For high-risk worksites, this means having at least one person holding a current HLTAID011 Provide First Aid qualification present at all times. Given the risk of cardiac arrest in electrical incidents, annual CPR renewal (HLTAID009 Provide Cardiopulmonary Resuscitation) is strongly recommended for the whole team.

First aid certificates expire after three years, and CPR components must be renewed every 12 months. If your team’s qualifications are out of date, a high-voltage incident is not the time to discover the gap. WorkSafe Victoria inspectors can and do check first aid compliance during site visits, and inadequate coverage can result in on-the-spot improvement notices or fines.

Book First Aid Training with AB First Aid in Tullamarine

AB First Aid offers nationally recognised first aid and CPR training for electrical teams and construction sites across metropolitan Melbourne and regional Victoria. Our practical, scenario-based training is designed for workers who need to be ready to act under pressure — not sit through a lecture.

We run regular public courses from our training centre in Tullamarine and can deliver on-site group training at your worksite. Whether your team needs full HLTAID011 Provide First Aid certification, annual CPR renewal, or a group session tailored to electrical trade hazards, we are here to help.

View our public course schedule or contact us to book group training for your electrical team today.

References

• Safe Work Australia. (2021). First Aid in the Workplace Code of Practice. Retrieved from safeworkaustralia.gov.au
• WorkSafe Victoria. Occupational Health and Safety Regulations 2017 (Vic). Retrieved from worksafe.vic.gov.au
• WorkSafe Victoria. Electrical Safety. Retrieved from worksafe.vic.gov.au
• Australian Resuscitation Council. (2021). ARC Guidelines — Cardiopulmonary Resuscitation. Retrieved from resus.org.au
• Safe Work Australia. Electrical Hazards. Retrieved from safeworkaustralia.gov.au
• Victorian Legislation. Occupational Health and Safety Act 2004 (Vic). Retrieved from legislation.vic.gov.au