Fatal incident resulting from electric shock injuries
WARNING: MAY CONTAIN DISTRESSING CONTENT TO SOME READERS
Earlier this year, an electrical worker received a fatal electric shock while upgrading a split air-conditioning system located on the metal roof of a commercial building. The worker had completed the installation of the compressor unit, mounted the base of the isolating switch, and re-routed several thermoplastic-sheathed cable (TPS) cables into the switch enclosure.
In order to provide a temporary power source to which they could connect a vacuum pump, the worker fitted an unswitched socket-outlet to one of the TPS cables. The socket outlet was not fixed in position and the temporary setup presented accessible single insulated conductors.
After re-energising the circuit, the worker returned to the work area and subsequently came into contact with an exposed, energised conductor, resulting in a fatal electric shock. The air-conditioning final sub-circuit on which they were working did not require RCD protection.
This tragic incident underscores the importance of carefully managing task sequences to prioritise electrical safety at every stage and the significant risks of working on or near exposed energised parts.
It is crucial to never assume - always test before you touch. And when it comes to electrical safety, remember - there's no such thing as temporary electrical work. Safety switches save lives.
These findings are not yet confirmed, and investigations are continuing into the exact cause.
Safety issues
Electric shocks can cause muscular contractions, heart palpitations, nausea, cardiac arrest, breathing arrest, burns and other cellular damage. They can also cause other injuries, especially if the shock causes a worker to fall from heights, such as roofs, ladders, scaffolding and elevated work platforms.
The risks associated with electrical work must be controlled and the control measures clearly communicated to workers.
Common electrical risks:
- Electric shock by direct or indirect contact, ‘step-and-touch’ potentials, tracking through or across a medium, or by arcing, for example:
- contacting a live terminal within energised electrical equipment (direct contact).
- from the earthed enclosure of an air conditioning unit when an active earth fault occurs (indirect contact).
- Fire, arcing or explosion causing burns and injury.
- Toxic gases causing illness or death (burning and arcing associated with electrical equipment may release various gases and contaminants).
Ways to manage health and safety
Taking steps to manage risks is a condition of doing business in Queensland. 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. This responsibility is covered by your primary duty of care in the Electrical Safety Act 2002 and the Work Health and Safety Act 2011.
The Electrical Safety Act 2002 places duties on people to ensure electrical safety. People who have a duty include persons conducting a business or undertaking (PCBU), designers, manufacturers, importers, suppliers, installers, repairers, persons in control of electrical equipment, contractors, and workers.
Where the Work Health and Safety Act 2011 and the Electrical Safety Act 2002 both apply, the Electrical Safety Act 2002 takes priority.
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
Effective control measures for electric shock are often made up of a combination of controls. Under section 16 of the Electrical Safety Regulation 2013 (ES Regulation), a PCBU must ensure that prior to electrical work being performed on electrical equipment, the electrical equipment has been de-energised and cannot be inadvertently re-energised while the work is being performed.
Section 17 of the ES Regulation requires licensed electrical workers to take precautions to prevent de-energised equipment from being inadvertently re-energised. They must ensure:
- a suitable warning sign under Australian Standard 1319 (AS1319) (safety signs for the occupational environment) is attached to the device in a prominent position.
- the device is locked when in an open position, for example:
- using a personal lock to lock an air-conditioner isolator in the open position.
- using a locking device that stops a miniature circuit breaker from being closed.
- placing a lockable shroud on the male inlet plug of electrical equipment.
- the device is prevented from being accidentally closed, for example:
- disengaging a circuit breaker so that the circuit breaker is separated from the busbars.
- removing circuit cables from the fuse or circuit breaker.
- inserting a mechanical restriction.
As a worker, you must take reasonable care for your own electrical safety and not adversely affect the electrical safety of others. You 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.
Effective control measures for work involving electricity are often made up of a combination of controls. A safe system of work for managing the risk of working in areas involving electricity can include but is not limited to the following actions.
Turning the power off:
- Ensure the power is off at the main switchboard and that adequate isolation has been confirmed at the main switchboard. The isolation should be isolated in such a way to prevent inadvertent re-energising until the electrical work has been completed.
- Some electrical equipment such as hot water systems or stoves may have a separate switch. It is safest to turn off all the switches and circuit breakers at the main switchboard.
- Complete a pre-work risk assessment of the area by looking around to identify any hazards that may pose risks. These may include for example:
- high temperatures - being aware heat and humidity may cause heat stress.
- asbestos.
- structural stability.
- accessibility to the work area (like cramped and awkward positions).
- location of electrical cables, fittings and equipment, water, or gas piping
- possible presence of dangerous wildlife (such as snakes).
- other objects or materials that could cause an injury (e.g., protruding nails, metal sheeting etc.).
- even with the power off, ensure contact with electrical cables and equipment is avoided as some cables, such as consumer service lines, may still be live. Also check for solar PV systems which may have DC supply cables that are live during daylight.
Turning off electricity to the property at the main switchboard does not turn off the electricity supply from the street to the switchboard. This means the incoming overhead service lines and the cables supplying the switchboard will still be energised. Extreme care must be taken to avoid touching any of these live overhead electrical lines or service supply lines.
Information training and instruction
PCBU’s should:
- develop safe work practices and procedures and ensure they are followed. This includes appropriate instruction, information, and training on isolation procedures.
- develop control measures in consultation with workers performing specific tasks and consider any training they require or already have. Formal or on-the-job training may be appropriate depending on the circumstances. Examples include:
- induction training - to ensure new starters or workers new to a job are trained on safe systems of work and other relevant health and safety matters.
- supervisor and management training – to ensure that safety issues are appropriately managed at the workplace.
- work specific training - to ensure that workers carrying out particular work are trained on any electrical and other risks specific to the work, as appropriate. For example, always using a voltmeter or multi-meter to test and confirm the equipment you are working on is not energised.
- emergency procedure training - to ensure workers know what to do in the event of an emergency, (e.g., procedures to follow if a person receives an electric shock).
- first aid training —to ensure appropriate procedures are followed for administering first aid, (e.g., proper treatment for electric shock).
Any remaining risk must be minimised with suitable personal protective equipment. For example, using electrical insulating gloves which have been electrically tested in accordance with Australian Standards and rubber soled boots.
More Information
- Managing electrical risks in the workplace code of practice 2021 (PDF, 1.34 MB)
- Hazardous electrical environments
- Supervising electrical apprentices (PDF, 0.15 MB)
- Electrical safety for apprentices - film
- There’s no such thing as a safe shock - film.
Have you been affected by a workplace fatality, illness or serious injury?
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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.