Joule Burn
Definition
Thermal tissue injury at an electrical contact point, produced by the conversion of electrical energy to heat (Q = I²Rt). Characterised by pale, raised, indurated coagulative necrosis with nuclear streaming on histology. The forensic entry-point mark in low-voltage electrocution.
- Formula
- Q = I squared R t
- Tissue effect
- Coagulative necrosis
- Histology marker
- Nuclear streaming
- Context
- Low-voltage electrocution entry point
Common questions
How is a Joule burn told apart from an ordinary thermal burn?+
Histologically by nuclear streaming, elongated and aligned nuclei at the contact point, and by an entry pattern that follows the current path through the body rather than the diffuse pattern of radiant heat exposure.
Why does the location of a Joule burn matter in scene reconstruction?+
It marks the point where current entered the body, which helps investigators establish the contact geometry between the victim and the electrical source.
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