Arc Flash
Definition
Plasma discharge between a charged high-voltage conductor and an earthed object, reaching 10,000-20,000 K. Causes flash burns to skin, ignites clothing, and produces blast barotrauma before direct current contact is established.
- Mechanism
- Plasma discharge, conductor to earthed object
- Temperature
- 10,000 to 20,000 K
- Injuries caused
- Flash burns, clothing ignition, blast barotrauma
- Voltage context
- High-voltage systems
Common questions
How is an arc flash injury forensically distinguished from a contact electrocution injury?+
Arc flash burns typically show a radiant flash-burn pattern over exposed skin and clothing damage from ignition without a discrete current entry and exit wound, whereas contact electrocution produces localized entry and exit marks where current actually passed through the body.
Why can arc flash cause fatal injury without direct electrical contact?+
The plasma temperature and pressure wave alone can cause severe thermal burns, ignite clothing, and produce blast trauma from the rapid expansion of superheated air, all before the victim's body becomes part of the current path.
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