An arc flash temperature can reach as high as 2,800 to 19,000 °C (5,000 to 35,000 °F). By comparison, the temperature of the surface of the sun is estimated at 5,500 °C (9,932 °F).
Arc flash and blast explosions produce some of the highest temperatures known to occur on earth - up to 35,000°F at the arc terminals. Arc flash is described as the light and heat created from an arc flash and arc blast explosion.
The intense heat from an arc causes the sudden expansion of air. This can result in a blast with very strong air pressure (lightning is a natural arc).
All known materials are vaporized at this temperature. When materials vaporize they expand in volume (copper - 67,000 times, water to steam - 1,670 times.) The air blast can spread molten metal to great distances with force.
Serious burns are common at a distance of 10 feet. Staged tests have demonstrated an arc flash temperature greater than 437°F on the neck area and hands for a person standing close to an arc-flash.
Additional hazards that can occur include:
• Damage to Eyes: Infrared and ultraviolet radiation can damage unprotected eyes.
• Molten Metal: Arcs can spray droplets of molten metal at high-speed to unprotected parts of the body.
• Shrapnel: Metal shrapnel created by an arcing fault can injure the body.
• Metal Vapor: Vaporized metal can be created causing serious injury if inhaled.
• Air Pressure: Extreme arc-flash events can create air pressure waves similar to chemical explosions. These have thrown workers across rooms and knocked them off ladders.
• Hearing damage: The sound magnitude has been shown to be more than 140 dB within 2 to 3 meters of an arc.