Electricity is at the heart of modern life and work. It’s easy to be oblivious of the hidden and lethal dangers of power in the workplace.
Words by John Gibson
In modern society, we have become so reliant on electricity that it has become nearly as vital as clean drinking water. Without reliable power supply in the workplace or at home, we have pretty much become incapable of performing the most basic of functions. With so much existing electrical infrastructure to meet this demand, much of it situated in close proximity to other services, working under or around power lines is quite commonplace.
We are all aware of the risks in theory, but how many of us can actually comprehend and predict how electricity will behave, or the true level of risk?
Unfortunately, a recent spate of incidents involving overhead powerlines has resulted in the deaths of two Australian workers, and severe injuries to many more.
Because powerlines hang there, relatively dormant, their deadly potential is grossly underestimated, largely due to complacency.
Unlike other potentially deadly hazards that exist in the workplace, electricity is invisible – it makes no sound and has no odour. Various control measures and legislative documents have been in existence in one form or another for many years; however, their effectiveness is somewhat questionable when you see the statistics on incidents involving overhead powerlines. While these deaths are a tragic reminder to ‘‘look up and live”, that alone will not be enough to have a lasting impact on the rate of such incidents occurring.
The traditional approach to minimising the risks associated with overhead powerlines has been predominantly administrative, relying on human intervention. PCBUs have a responsibility to ensure all workers are aware of the location of live powerlines, the regulatory exclusion zones and the importance of maintaining a safe distance from them. Powerlines can be de-energised in some cases, but in others they cannot.
A live powerline still looks like a dead one to me. The use of trained/certified spotters can be effective. However, you’re only one lapse in judgement or momentary loss of concentration away from disaster. There has, however, been some new technology developments in this field in recent times with the potential to make powerline related injury and/or death a thing of the past.
A retro-fit system with the capability of sensing the electrostatic field of any A/C high voltage powerline, no matter what the current, has been developed and refined in Australia. Information is fed to a unit located in the operator’s station, providing both visual and audible warnings of the proximity of live powerlines. The user interface enables the operator to override and mute alarms as the need arises, but in any case, by that time, the impending risk has been identified and acknowledged. Many major construction companies in Australia have tested this technology, including Fulton Hogan, John Holland and McConnell Dowell. Perhaps this will become the next ‘‘Excavator ROPS’’ or ‘‘Crane valve’’ required as minimum spec.
This technology, developed in Australia, not only has an application in the civil infrastructure industry, but also mining, agriculture and aviation. The reliance on a ‘‘plug and play’’ electronic device to mitigate the risk of electrocution should never completely replace commonsense and conformance with statutory regulations.
However, in conjunction with your existing SWMS this technology offers additional peace of mind.
Having witnessed the aftermath of plant contacting powerlines on more than one occasion, I can attest to the unpredictability of electrical currents, even with rubber tyred equipment. While rubber is an insulator, most products when burnt will produce carbon, which is an excellent conductor. A wet or muddy tyre quickly becomes a fuel source capable of conducting electricity back to the earth, with an in-built supply of pressurised air to increase the risk of explosion.
Electrical currents can spike onboard computers causing engines and implement control circuits to fail, rendering the machine incapable of breaking contact with downed powerlines. When such incidents occur, panic often sets in and rational thought goes out the window. If you ever find yourself in such a situation, it’s best to stay in the machine, unless of course it has caught fire or there is some other risk associated with remaining in the cab. Should it be necessary to vacate the machine cabin, it is imperative that you jump well clear of the machine making sure not to touch the machine and the ground at the same time. Once on the ground, the electrical current may be radiating outwards through the ground. The best way to evacuate the area is by jumping away kangaroo style, or shuffling your feet maintaining contact with the ground at all times.
Ultimately, we go to work out of necessity and we all just want to get home safely in the same condition we arrived at work. PCBUs have a legal obligation to take all necessary steps to ensure your safety, through whatever means necessary. Technological advancements have both simplified and complicated so many things we do each day.
Regardless of how clever we get as a species and what we invent next, the best pieces of safety equipment you’ve got onsite are your eyes, your ears and your brain. Slow it down, survey your surroundings, think it through, don’t take unnecessary risks and get home safe. Don’t die for a deadline.