Identifying high voltage hazards
High voltage hazards are a serious risk to workers and the public due to the massive quantities of energy that can be released. Understand the risks and how to protect yourself and others.
What do we mean by high voltage hazards?
High voltage is a form of electricity with a high potential energy. Power plants, substations, overhead and underground powerlines, and large motors are examples of high voltage equipment and installations.
To be considered high voltage, the equipment or installation must operate at an alternating current (AC) voltage exceeding 1000 volts, or a ripple free direct current (DC) voltage exceeding 1500 volts.
What are the risks of high voltage hazards?
The consequences of an incident involving high voltage electricity are usually more significant than for low voltage. They include:
- severe injury or death from electric shock (which may be received by direct or indirect contact, tracking through or across a medium, or by arcing)
- burns from arcing, explosion or fire
- illness or death from toxic gases released by burning and arcing
- injury or death caused by violent muscle contractions leading to loss of balance and a fall.
The risks arise from working on or near the high voltage equipment or installation itself and from:
- induction from other circuits and communications equipment, such as radio transmitters
- a build-up of static charge due to weather conditions
- feedback from secondary or tertiary systems
- stored energy in high voltage capacitor banks
- working under or over other live conductors.
It’s not just workers at risk—the public is also at risk through day-to-day activities. For example, flying drones and kites, paragliding, moving sailing craft and home fruit picking all present risks of contact with powerlines. Even tree trimming near powerlines (PDF, 1.36 MB) has caused some serious incidents.
How do I manage the risks?
Workers and management can work together to reduce the risks of working around high voltage equipment.
You have a responsibility under the Electrical Safety Act 2002 (ES Act) and Work Health and Safety Act 2011 (WHS Act) to take reasonable care for your own health and safety and for others who may be affected by what you do or don’t do.
You must follow instructions from supervisors, use equipment properly and adopt safe work policies and procedures. If something is unclear, ask for an explanation.
You have legal responsibilities as outlined in the Electrical Safety Act 2002 and Work Health and Safety Act 2011 for the health and safety of every worker and visitor. Where both acts apply, the Electrical Safety Act takes priority.
The four-step risk management process below will help you to meet your responsibilities under these laws.
Four steps to manage risk
Think about what could contribute to a high voltage incident.
- scale and scope of the work
- age of the equipment and installation
- whether the site must remain energised (or can be de-energised)
- proximity of the work to other energised equipment or parts
- experience and capability of the workers (are they appropriately licensed or authorised under the Electrical Safety Act 2002?)
- environmental conditions, such as unfavourable weather.
Talk to others about the possible hazards. This includes workers who are always on site as well as those who are part of the high voltage work crew.
Consider past incidents involving high voltage work by reviewing your workers’ compensation claims, recorded incidents, sick leave and worker complaints. Plan what you can do to prevent the same things happening again.
Identifying hazards should be an ongoing activity that is organised at least once a year or whenever there is a change in equipment, facilities or work practices.
Once you identify possible risks, make a risk assessment and decide:
- who is at risk
- whether any effective control measures are already in place
- what actions you could take to control the risk
- how urgently you should act.
You can use this risk assessment template (DOCX, 0.02 MB) to guide you and record your assessments.
The best way to control a risk is to remove the hazard completely. In the case of work around high voltage equipment, this is arranging de-energisation and isolation. If that’s not possible, you must reduce the risk as much as possible.
Ways to do this include:
- ensuring the high voltage equipment or installation remains compliant with all relevant technical and safety requirements for the duration of its operating life
- using the safe approach limits detailed in the Electrical Safety Regulation 2013
- using appropriate lock-out and tag-out procedures
- putting physical control measures in place such as insulation and guarding
- only allowing a competent, experienced and licensed person to undertake the work
- ensuring appropriate PPE is worn.
Planning for work around high voltage equipment is an essential risk control. Section 9 of the Electrical safety code of practice 2021 - Managing electrical risks in the workplace (PDF, 1.25 MB) will help with this.
More information can be found in the Electrical safety code of practice 2020 – Working near overhead and underground electric lines (Appendix B) (PDF, 0.47 MB).
You should check regularly to make sure the control measures are working. If you find problems, go through the steps again, review the information and decide whether you need new controls.
You must review controls:
- when you become aware that a control measure is not working effectively
- before a change that might create a new risk
- when you find a new hazard or risk
- when your workers tell you that a review is needed
- after a health and safety representative requests a review.
Standards and compliance
- Electrical Safety Act 2002
- Electrical Safety Regulation 2013
- Work Health and Safety Act 2011
- Work Health and Safety Regulation 2011
Codes of practice
- Electrical safety code of practice 2021 - Managing electrical risks in the workplace (PDF, 1.25 MB)
- Electrical safety code of practice 2020 – Working near overhead and underground electric lines (PDF, 0.47 MB)
- How to manage work health and safety risks code of practice 2021 (PDF, 0.65 MB)