Arc flash incidents get a great deal of publicity, and for good reason: electrical explosions caused by arc flash happen almost every day, causing a great deal of damage both to people and to the economy.

But what exactly is an arc flash—and what causes one?

Simply put, an arc flash is an indoor bolt of lightning followed by a fire ball that occurs when equipment is being operated and the electrical potential between two phases or phase to ground is not contained. The heat and energy created by the arc flash is enough to almost instantly melt copper, aluminum, or steel and cause a runaway fault in a system.

A number of factors can make this happen:

• Poor electrical design
• Equipment substitutions
• Human error (accidental contact), whether through improper training or carelessness/overconfidence
• Corrosion, accumulation of dust, or breaks in insulation
• Dropped tools and other conductive items

Arc flashes can happen in any electrical equipment above 24 volts, with significantly increasing risk and damage potential at 120 volts and above.

Want to learn more?

The best way to prevent arc-flash incidents is a complete power system study. Salas O'Brien has been doing these studies for decades—and we'd love to share our expertise with you.

Click below to download our white paper on arc flash risk assessments. And contact us or call us at 877.725.2755 if the paper raises any questions!