Arc flash incident with high voltage equipment

WARNING

MAY CONTAIN DISTRESSING CONTENT TO SOME READERS

In 2025, a worker received burns following an arc-flash incident during works on high voltage electrical equipment.

Initial investigations indicate electrical work was being carried out in relation to the installation of cables and circuits associated with a new transformer, when it appears an isolator was switched, resulting in a short-circuit at the cable connection.

This has caused an arc flash.

Investigations are continuing.

IMPORTANT

These findings are not yet confirmed, and investigations are continuing into the exact cause.

Safety issues

An arc flash is a release of electrical energy that causes an explosion, which can reach temperatures of up to 20,000 degrees Celsius. An arc flash usually occurs in large switchboards but can also occur in smaller switchboards, electricity supply pillars or large electrical equipment. Watch the arc flash safety film for more information on this hazard.

Common causes of arc flash include:

unsafe work practices and procedures
foreign materials
breakdown of busbar insulation
electrical equipment failure such as a switch, circuit breaker or loose cables
contacting energised equipment with uninsulated tools
using test equipment not designed or rated for the job.

Electrical work on energised electrical equipment can put you at risk of inadvertent contact with an energised part, resulting in electric shocks and exposure to an arc flash.

The risk of working near energised electrical equipment can be as great as working on the parts themselves. There have been a number of serious incidents where workers have received significant injuries from an arc flash where they were working near exposed energised equipment and did not consider further upstream isolation.

Ways to manage health and safety

Effective risk management starts with a commitment to health and safety from those who manage the business. If an incident occurs, you will need to show the regulator that you have used an effective risk management process.

Use the hierarchy of controls to help decide how to eliminate and reduce risks in your place of work. The hierarchy of controls ranks types of control methods from the highest level of protection and reliability to the lowest. It is a step-by-step approach to eliminating or reducing risks. You must work through the hierarchy of controls when managing risks, with the aim of eliminating the hazard, which is the most effective control.

Possible control measures to prevent similar incidents

Prevent arc flash incidents by eliminating the hazard. PCBUs and workers are required to de-energise electrical equipment (turn the power off and isolate the equipment) before electrical work occurs on or near electrical equipment.

Electrical safety laws prohibit electrical work on or near energised electrical equipment unless, the following prescribed circumstances apply:

it is necessary in the interests of health and safety that the electrical work is carried out while the equipment is energised, for example - on life-saving equipment
it is necessary that the electrical equipment is energised in order for work to be carried out properly
it is necessary for the purposes of testing to determine whether or not the equipment is energised
there is no reasonable alternative means of carrying out the work.

Note that testing energised electrical equipment is a form of energised electrical work. You may be required to reschedule your work to another time to ensure that you are not performing electrical work near energised electrical equipment. To determine the risks of arc flashes, the assessment must consider the level of possible fault current present.

Choose controls that most effectively eliminate or minimise the risk of working near energised electrical parts. This may involve a single control measure or a combination of two or more different controls including:

electrically isolating nearby electrical equipment or installations before starting work, and ensuring they can't be reconnected while the work is being carried out
the equipment is tested by a competent person to determine whether it is energised or not
using insulated or non-conductive physical barriers to prevent inadvertent contact with energised parts
ensuring workers have appropriate training, knowledge and skills to perform the work safely according to their experience and the tasks that their doing
ensuring testing procedures are in place to prove parts are de-energised before work commences
ensuring people not required for the work are excluded from the area, using screens, barriers and signage
consultation with the person who manages or controls the workplace
ensuring a risk assessment is developed to identify exposure to electrical risks
development of a safe work method statement is conducted, implemented and kept
appropriate personal protective equipment (PPE), tools and testing equipment is used by a competent person
a safety observer is present (unless the work is only testing and the risk assessment shows no serious risk associated with the proposed work).

Workers must comply with any reasonable instruction and cooperate with any reasonable policy relating to electrical safety at your place of work. If your employer provides you with equipment to do a job, you must use it in accordance with the information, instruction and training provided on its use. If something is unclear, or you are uncertain, ask for an explanation.

The control measures you put in place should be reviewed regularly to make sure they work as planned.

More Information

If this information has caused distress, there are services to help:

Lifeline – 24/7 crisis support service, including phone, texting and chat services.
Beyond Blue – information and support for anxiety, depression and suicide prevention for everyone in Australia.
Black Dog Institute – research and resources on mental health in the workplace.
SANE – helpline service, as well as resources on mental health.

Have you been affected by a workplace fatality, illness or serious injury?

For advice and support: