Arc flash – risks linked to wind turbines and windfarms
When it comes to safety whilst installing and maintaining wind turbines, all of us understand the importance of wearing a helmet, harness and suitable footwear
In fact, most employers wouldn’t dream of letting their teams on site without adequate protection and workers themselves are more than clued up when it comes to the latest safety requirements. However, the same can’t be said when it comes to the potentially fatal risk posed by an Arc Flash – a relatively misunderstood, but extremely common type of electrical explosion facing those working on or offshore, private or commercial wind turbine projects.
What is an Arc Flash?
Hotter than the sun and louder than a bullet, an Arc Flash is when an arcing fault releases dangerous levels of radiant energy, which vaporises metal that spews from the arc. The air is super-heated causing pressure waves that can throw individuals across rooms and create a deadly molten shrapnel.
It goes without saying; the extreme temperatures of an Arc Flash can burn clothing and human skin within fractions of a second, even if the operative is situated five or six metres away from the Arc Flash event. It can also result in an explosive pressure wave that can throw workers across the room and a sound blast that can rupture eardrums. An Arc Flash event is also accompanied by a bright flash which can cause temporary or even permanent blindness.
Treatment for those that survive an incident can require years of skin grafts, hospital stays and rehabilitation – they may never recover sufficiently to regain their lifestyle, so it’s safe to say that choosing the appropriate PPE is key when it comes to Arc Flash safety.
Posing a risk
Electrical in nature, Arc Flash poses a substantial risk to those working in the wind industry which is constantly growing in importance due to its potential to contribute significantly to our national energy needs.
When working on wind turbines or windfarms, Arc Flash incidents can occur in both low voltage environments as well as high voltage, with particular reference to the following incidents…
- Opening energised electrical cabinets and verifying zero energy (testing dead)
- Securing and removing lock out and tag out (LOTO) devices
- Conducting trouble shooting on energised equipment and parts
- Working on near or exposed live conductors
- Breaking ground to install turbines
It is worth noting that the above incidents are of broadly the same severity whether the turbine is part of a large commercial windfarm or one of the growing number of small scale turbines installed by businesses.
How to protect yourself
Arc Flash protection is found in specialist garments – everything from Arc Flash base layers to Arc Flash outerwear jackets and trousers.
Enhanced and effective protection comes through wearing layers of protective garments manufactured from inherent fibres and which feature specific Arc Flash resilient components. Without the correct high-quality garments, protection levels will be compromised. In addition to quality, it’s important to consider the longevity of the garment – depending on how it’s manufactured it may lose its effectiveness. Always look for products that feature Arc Flash protective qualities in the thread, as opposed to just a sprayed material, which will lose its impact over time.
Recognising that working offshore in the colder areas of the world means that warm clothing is an essential demand when working in the wind industry. Arc Flash resistant base layers have been developed that won’t compromise protection.
Choosing to wear non-Arc Flash resistant clothing can cause a lot of damage in an Arc Flash situation since the heat of the event can cause non-Arc Flash resistant clothes to melt into the skin.