Now, I'm not placing any blame on any person, company or anything else for the lack of information or training. The arc flash hazard is still something that is, in my opinion, making its way into the mainstream even though it has been on the books for years. Like everything else in the safety world, the codes pertaining to everything arc flash are ever-evolving too.
It wasn't until I started my job with Cirque du Soleil that I finally heard the term arc flash. My first impression on just the term was that it sounded like something terrible but how does it affect me? Well, let us get a quick run down of arc flash. Take it away Wikipedia:
An arc flash is an electrical breakdown of the resistance of air resulting in an electric arc which can occur where there is sufficient voltage in an electrical system and a path to ground or lower voltage. An arc flash with 1000 amperes or more can cause substantial damage, fire or injury. The massive energy released in the fault rapidly vaporizes the metal conductors involved, blasting molten metal and expanding plasma outward with extreme force. A typical arc flash incident can be inconsequential but could conceivably easily produce a more severe explosion (see calculation below). The result of the violent event can cause destruction of equipment involved, fire, and injury not only to the worker but also to nearby people.
In addition to the explosive blast of such a fault, destruction also arises from the intense radiant heat produced by the arc. The metal plasma arc produces tremendous amounts of light energy from far infrared to ultraviolet. Surfaces of nearby people and objects absorb this energy and are instantly heated to vaporizing temperatures. The effects of this can be seen on adjacent walls and equipment – they are often ablated and eroded from the radiant effects.
Isn't that something. But really, where would I ever come into contact with something that grandiose? Great question – go flip a breaker in your "found everywhere" (if you're in the U.S.) 120V service panel. Depending on what kind of work you have done on that panel or, more likely, downstream on wherever the circuit terminates, you could come in contact with an arc flash. Now it may not be as extravagant as the following, but the potential for harm is still there. Check these out:
These guys were lucky – they are still alive. I've even met an arc flash survivor who is happy to still be here but was really lucky to have survived and has some major scarring to show for it.
I really just want to put some awareness out there on this topic. The training session that is provided for us at Cirque is about 3+ hours for NFPA 70E, which only touches on arc flash. On the label to the right, you can find every bit of information on the panel, switchboard, or, in this case, dimmer rack that tells you how you should go about working on the equipment. All of your gear should have something along the lines as this label. It may not have all of the information this one does, but it should still warn of the risks.
If you aren't already aware of arc flash, using the safe practices required or generally trained in these matters, STOP YOUR DAILY ELECTRICAL TASKS and ask your employer or professor or whomever else may be responsible in training you to give you that training. Chance is, they may be unaware just like I used to be. If they are unaware, go ahead and direct them to the NFPA 70E material because further chances are that they are unaware of a lot of other things that could impact the everyday safety of you.
Here are some more resources to help you understand arc flash and that with proper training and personal protective equipment (PPE), there is nothing to fear:
- Arc Flash Forum – A global community about arc flash and electrical safety
- NIOSH Arc Flash Awareness Videos – Part 1, Part 2, Part 3
- Arc Flash Documentary from Con Edison – Con Edison is a manufacturer of flame resistant (FR) fabrics
- Westex Video Library – Westex is another manufacturer of FR fabrics which has a great library of multiple levels of arc flash videos with treated and untreated fabrics on mannequins. They also have a free DVD that you can order with their test videos to share in the classroom!
Just remember, if you don't feel safe doing something, you have every right to not do it. Just make sure you voice your concerns and ask for the proper training.