While this can certainly still be deadly, in higher voltage applications the chances of something far more dangerous happening start; arc flashes. While still possible at lower household voltages, high voltage applications; over 600V, have a significantly higher risk of arc flash, and with that comes a new multitude of dangers to be accounted for.
The most obvious one is the heat; where the electric current forces its way through the air, the massive amperage causes everything to superheat to incredible temperatures up to 20,000 Celsius; a temperature hotter than the surface of the sun! At these temperatures substances don’t exist which can withstand this temperature.
This temperature is fairly concentrated at the point where the arc flash occurs, the temperature will quickly drop with distance from the epicentre, despite this though, superheated matter including molten metal will be spewed out. This is more than capable of igniting clothing and other nearby material and it is for this reason that one of the biggest killers from arc flash incidents is burning on victims; where clothing ignites, victims can receive burning on a huge percentage of their body, the chance of infection then becoming extremely high. Here one of the most important things is to have FR clothing to stop this from happening.
Another big issue of arc flash incidents is the sheer amount of energy released, where tens of thousands of amps can be released at hundreds of volts, an arc flash lasting just a fraction of a second can release phenomenal amounts of energy comparable to explosives. Of course most explosives work on a principle of creating gasses from solids; since gasses take up a much larger volume than solids you get a very rapid expansion, which is also increased by the exothermic release of explosives. Comparatively, an arc flash releases almost all of its energy in heat and light, so the shockwave from an arc flash won’t have the same mechanical force as an actual explosive, it is significant enough to be dangerous however, many people are thrown across rooms and suffer irreparable damage to their hearing as well as eyesight from the extremely bright light emitted.
Stopping arc flashes is a tricky processes and one of the best tools against the dangers of arc flash is to know where they will happen, making arc flash assessments a hugely important part of industry. Another good way around arc flashes is to do work using hot sticks and hydraulic systems. Electrical PPE should be considered your last line of defence, so be careful out there.
