Arc Flash 101: Staying safe on-site

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Opinion

Mark Lant, technical sales manager at arc flash specialist, ProGARM, explains just what an arc flash is, why it is among the most dangerous risks on any work site, and how you can protect both yourself and your colleagues.

Most of us in the safety industry are familiar with an arc – an electric luminous bridge formed in a gap between two electrodes – but its severity and danger is often overlooked. An arc flash occurs during a fault, or short circuit condition, which passes through an arc gap, and, can result in devastating results if the correct equipment isn’t being worn.

Arc flashes can occur for several reasons, and their frequency is somewhat alarming. From being initiated through accidental contact or equipment that is underrated for the available short circuit current, to contamination or deterioration and corrosion of equipment, these are just a few of the many causes of an arc – making the risks higher than many first think.

In a nutshell, an arc flash is high risk, high danger and can result in devastating consequences. Expelling large amounts of deadly energy, causing an ionisation of the air, an arc flash can reach temperatures as high as 20,000°C. To put this danger into context, an arc flash is hotter than the surface of the sun!

So, what can happen if there’s an arc flash?

We’ve already established that arc flashes can be devastating; however the scale of destruction really can’t be underestimated – here are some examples of how lethal an arc flash strike can be: 

  • The high temperature can set fire to clothing and severely burn human skin in fractions of a second, and at a significant distance from the event
  • The heat can also result in ignition of any nearby combustible materials
  • Metal parts near the event can liquefy or vaporise. This will rapidly expand in volume as it changes state from a solid to vapour, resulting in explosive pressure and soundwaves
  • The pressure wave can knock workers off balance, ladders or even throw them across the room against walls or other equipment
  • The sound blast can cause eardrums to rupture resulting in temporary or permanent hearing loss
  • Molten metal can be sprayed by the blast throughout the vicinity
  • Solid metal debris and other loose objects, such as tools, can be turned into deadly projectiles by the explosion
  • The bright flash can result in temporary or permanent blindness. 
What is the legislation?

With such drastic consequences, you would be forgiven for expecting strict legislation to be in place in order to protect the people working in these conditions. Especially given the serious – or in many cases, fatal – consequences of getting it wrong. However, there is little appropriate protective measures to mitigate against it, leaving the UK workforce at often extreme risk.

While HSG47 goes some way to address the risks posed by cable strikes, it remains vague and unspecific, with no onus on employers to adequately protect their staff when in the field. In fact, American research concluded that 70% of workplace electrical injuries are caused by an arc flash, not just a simple electric shock, yet many people simply do not know this. When the consequences of getting it wrong are so serious, it is important to properly understand this distinction in order to effectively protect your teams – and yourself – from arc flash hazards.

So, who’s at real risk? Arc flash hazards occur in many sectors, including utilities, industrial electrical and the petrochemical industries. Safety officers are increasingly aware of the dangers posed by arc flash incidents and take advantage of the various forms of protection to guard their teams against exposure.

How should you protect your staff?

Unfortunately, there is no way to fully protect yourself from an arc flash incident, however, protective clothing can minimise risk and prevent your staff from facing the most fatal of consequences. If worn correctly, arc flash protective clothing and equipment can help to prevent serious injury and fatalities. Here are some key considerations to implement when auditing safety against arc flash.

Prevention is better than the cure: As with all on-site health and safety matters, prevention is the most effective way to stay safe. To ensure the correct measures are taken, education is key. With this in mind, we’d recommend that first and foremost any work force that could be impacted by an arc flash incident is trained on how to optimise safety on site – helping to reduce the chances of experiencing an arc flash from the offset.

Educating your workforce: If your workforce doesn’t properly understand the dangers posed to them by arc flash hazards because it hasn’t been explained properly, then they may not wear the clothing correctly, leaving them vulnerable to the risks of an arc flash as a result. Training a workforce is essential to ensuring optimum safety levels on the ground. It’s of paramount importance that those in the field are aware of how to wear their PPE – for example an unzipped jacket, won’t provide the sufficient protection, however wearing an arc flash vest would – meaning there is flexibility when it comes to selecting product that will both protect and be comfortable to wear.

Specialist garments: Arc flash protection is found in specialist garments – everything from insulating warm arc flash base layers to arc flash waterproof 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. If you don’t have the correct and quality garments, your protection levels will be compromised. In addition, it’s important to consider longevity of the garment – depending on how its 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.

Awareness raising: Not all arc flash protective garments are manufactured equally. Whilst many garments meet minimum standards, it’s important to ensure that the level of protection and quality of garment are sufficient to provide the protection the wearer needs. Choosing to work with a specialist, rather than generalist arc flash clothing provider is also incredibly important – when the stakes are this high, is it really worth compromising on safety?

Arc flash remains a pressing issue, and one that many of the UK workforce aren’t fully educated on. To ensure your workforce is protected from the potentially fatal risks of an arc flash, education and prevention are a number one priority. At present, there is a real lack of awareness when it comes to arc flash dangers and with limited guidance from the government, it is our responsibility as an industry to champion work place safety. When lives are at stake, it’s essential that you invest in high quality and specialist expertise to ensure safety remains a number one priority.