Arc flashes can occur for several reasons and their frequency is 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 and can result in devastating consequences. Expelling large amounts of deadly energy, causing an ionization of the air, an arc flash can reach temperatures as high as 20,000°C. To put this into context, an arc flash is hotter than the surface of the sun. The scale of destruction cannot be underestimated:
- 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 vapor, 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
- Protective clothing can minimise risk and prevent 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.
Key considerations to implement when auditing safety against arc flash include:
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. Any workforce that could be impacted by an arc flash incident must be 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 is 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 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 do not have the correct garments, your protection levels will be compromised. In addition, it is 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.
Arc flash remains a pressing issue and one that many of the UK workforce are not fully educated on. To ensure your workforce is protected from the potentially fatal risks of an arc flash, education and prevention are vital. At present, there is a lack of awareness to the dangers and limited guidance from the government. It is the responsibility of industry to invest in specialist expertise to ensure safety remains a number one priority.