Have you ever waited for a subway or metro, and you see a huge spark by the third rail when the train pulls into the station? That is an arc flash. Found in nature in lightening, arc flashes can also be found in manufacturing, welding, construction, and other environments that use electricity. Arc flashes can seriously injure or kill those unfortunate enough to stand in its way. That is why the Occupational Safety Hazard Administration, or OSHA, recommends arc flash protective clothing. Using arc flash protective clothing saves lives, and also means you have nothing to fear from arc flashes.
For those who do not wear arc flash protective clothing or other arc rated clothing, arc flashes may seem like a term of art. As mentioned, they are frequent, and most people who have used rapid transit see them at least once. Arc flashes are when electricity breaks down gas, and results in the creation of plasma, another state of matter. This plasma, while short lasting, can turn normally non conductive media, like air, into conductive media for a short period of time. Many workers need arc flash protective clothing because the terminals of an arc flash can heat to 20,000 C, vaporizing most metal, skin, and organs.
Those who wear arc flash protective clothing are protected by a layer of insulation. Arc flash protective clothing is rated by its ability to withstand calories of heat per square centimeter. Many arc flash protective clothing manufactures even make fireproof clothing, such as womens fire resistant clothing, that lets all workers have comfort. Nevertheless, arc flash protective clothing should be viewed as a last resort. Focus should be on procedures that can reduce or even eliminate arc flashes, although this is not always possible.
Maintenance uniforms and FR coveralls are part of the arc welding uniform. Using arc flash protective clothing may be a last line of resort that protects him or her from major damage. As a result, OSHA finds it in the public interest to recommend and require arc flash protective clothing for all workers at risk of arc flashes.