Most electricians and other assorted technicians who work with high voltage have seen an arc flash.
They’re blinding, loud, and frightening affairs. If you’ve been in the field for a while you might even have a couple of burn scars from less serious events.
Protecting yourself from electricity is always the first thing you should do when you’re in the field.
If you’re looking for a real solution to protect yourself from arcing electricity then you’re in the right place. Let’s jump right in and we’ll show you the steps you need to protect yourself.
While they’re a known danger in any field working with high-voltage power, many people don’t understand how arc flashes occur.
Understanding is the key to avoiding them in the first place.
Protective measures are great, preventative measures can keep the arc from happening in the first place.
An arc flash generally occurs during a short circuit. In lower energy systems this usually requires physical contact with charged electrodes. In higher energy systems these arcs can even travel through the air.
While the whole flash occurs in a fraction of a second there’s a lot at play during the event.
An arc flash can reach temperatures of 35,000°F. The amount of energy released during one is pretty incredible, it’s really just an explosion.
The event is known as an arc flash but actually has two components.
The arc flash itself is the discharge of voltage, raising the temperature of the conducting material and whatever the arc has hit in tiny fractions of a second.
The secondary effect of the arc flash itself is known as the arc blast. This is a blast wave which occurs at greater than the speed of sound and can have some heavy concussive effects on anyone nearby when it happens.
In addition, the arc blast includes any shrapnel or liquid metal which is ejected from where the arcing incident occurred in the first place.
The majority of arc flashes occur in low energy systems by accident. While they can be loud, blinding, and frightening they often leave the person unharmed or with minimal burns.
In high energy systems, however, the arc flash is more similar to an actual explosion than the small snap and flash of light which occurs at lower voltages.
Keep in mind this: arc welders work through what is essentially a controlled arc blast. They can weld steel with 24V of input energy, that alone should make you think twice.
The voltage itself is dangerous enough, causing burns and other damage. At higher voltages, it can outright kill a person. If someone gets hit with an arc from a powerline, for instance, there’s not going to be much left of them.
Other hazards include blinding from the flash itself, becoming deafened from the sound of the explosion, and falling hazards if you’re working on a ladder or rooftop.
There’s also another, hidden danger. During an arc flash event, metal can become vapor in a fraction of a second, producing toxic, dangerous fumes that you may not even be aware are there.
At extremely high voltages even the concussive force of the arc blast can be a danger all on its own.
Anytime you’re working with high-voltage equipment you should follow all of the proper procedures. Chances are that if you’re an electrician or technician you know what they are… even if you don’t always follow them.
The biggest thing is to always be aware of what you’re doing. A touch of a screwdriver or a bent outside panel over high-voltage breakers can both cause an arc event on lower energy systems.
When you’re working with anything 400V or over you should always pay special attention to what you’re doing. An arc flash in that range can easily kill a person who’s not wearing PPE.
One of the most important standards is to de-energize equipment before working on it.
Unfortunately, good practices are unable to prevent arc flashes entirely. Sometimes it’s just a fault in the electrical system being worked on.
That’s where proper clothing and PPE come in.
Anytime you’re working with electricity you’ll need to make sure you’re dressed properly. Even with low energy equipment, it’s essential.
Conductive jewelry needs to be removed, for instance.
You should be wearing long sleeves, long pants, and work gloves at the minimum. All materials should be made of cotton or another natural fiber which will burn instead of melt.
Melting synthetic fibers can make the aftermath of an arc flash even worse if it makes direct contact with you. All of your clothes should be either fire or melt resistant.
Yes, even your underwear.
However, dedicated PPE is a much better idea.
For those who face the risk of arc flashes on a regular basis, it’s important to invest in solid PPE. It can save your life, making a potentially fatal incident much less serious.
For the average worker, fire resistant outer layers will protect well enough. They should be rated for both arcing and fire resistance.
Gloves should also be fire resistant and made of a non-conductive material like rubber or leather.
Finally, you have to make sure that your face is protected. At the very least this means ANSI rated safety goggles but in most cases where dedicated PPE is required, you’ll want to make sure you have a full mask to protect from anything thrown during the arc blast portion of the event.
Make sure to comply with OSHA regulations and you’ll be on the right track.
Arc flashes can result in a near-miss. One of those is usually enough for most people to understand why the need to protect yourself.
Arc events take out 5-10 people per day. That’s not including unreported events or minor ones which result only in contact burns.
Understanding how to keep yourself safe is a matter of understanding the why of arc flashes, as well as taking the proper precautions to avoid causing them. When you add in PPE on top of it you’ll be in a much better position than those who try to just make do.
If you’re looking for more tips and tricks for your PPE and personal, then check out our blog.