WA company fined $65,000 for arc flash incident

Western Australian company FQM Australia Nickel has been fined $65,000 after a worker was injured in an electrical arc flash at the company’s Ravensthorpe Nickel Operations, according to an update by the Queensland Electrical Safety Office.

Shane Russell, an electrician on the site, was working at an electrical substation in July 2011 when the arc flash occurred. Russell sustained burns to his left hand and the left side of his face as a result.

An investigation by the Department of Mines, Industry Regulation and Safety in Western Australia found an internal report by FQM into a previous incident four months earlier had identified the danger of working on the Motor Control Centre (MCC) without full isolation.

There was no hard barricade behind the isolator to prevent accidental contact with uninsulated live bus bars. The potential consequence of an arc flash reoccurrence was identified as being ‘major’ and the likelihood was ‘possible’. The investigation recommends the MCC should be fully isolated prior to working on the module and a hard barricade be installed to prevent accidental contact with the live bus bars. This incident was preventable and had the potential to be fatal.

The Electrical Safety Office is reminding workers that it is very important to consider the environment and nature of work you intend to perform. Working on or around an electrical installation with a high fault level requires the highest levels of control because of the potential risks. This includes performing work such as isolation, testing and visual inspections.

For example, a switchboard supplied by a 500 kVA transformer could have a fault level of near 14,000 A, with arc flash temperatures reaching as high as 19,400°C. In these circumstances, the risks associated with working near energised parts can be just as dangerous as those associated to performing live work itself, and appropriate control measures must be implemented.

It is important to remember that high fault currents are not just limited to large main switchboards, and can also occur within other locations of an electrical installation such as smaller switchboards, electricity supply pillars or electrical equipment. 

Before any work is done, it’s important to ensure the following steps have been taken:

• Consult with the person in control of the electrical equipment in regards to the de-energisation of the equipment which the work is to be performed on or near.
• Identify the hazards and assess the risk. Ensure that a site-specific written risk assessment has been completed for the work that is to be performed.
• Control the risks using the hierarchy of control by following these steps: 
  • Eliminate the hazards as far as is reasonably practicable. If elimination is not reasonably practicable, you must minimise the risk by doing one or more of the following steps.
  • Substitute (wholly or partly) the hazard creating the risk with something that creates a lesser risk.
  • Isolate the hazard from any person exposed to it.
  • Implement engineering and administrative controls.
  • Wear personal protective equipment (PPE).

Administrative controls and PPE should only be used as a last resort when there is no other practical control measure available. Every site should be treated separately. Potential short-circuit current should be determined at the point within the installation where the work is to be conducted and appropriate controls identified from the risk assessment should be put in place.

The highest level of risk control, reminds ESO, is to eliminate the hazard altogether by de-energising the switchboard or equipment.