Power brand

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Current mark caused by a 20 kV arc

Electricity marks (also lightning marks ) are injuries caused by the effects of electric current on people and are the result of electrical accidents .

Touching in the area of low-voltage a voltage-carrying part, it comes at a sufficiently high voltage and low resistance to electrical current flow through the tissue which, due to the contact resistance between the skin and the object to a strong may heat development and the associated burning may result . The reason is the high electrical power that occurs in the area of ​​the tissue, which has a thermal effect. The duration of exposure and the specific heat capacity of the tissue, primarily dominated by water, are also important for the extent of thermal damage .

In the area of high voltage , and also with lightning, there is no direct contact with live parts with current brands, but a current flow occurs even before a possible conductor contact due to an arc fault (flashover). Since the arc is very hot, severe thermal damage suddenly occurs in the area of ​​the current entry or exit point on the tissue. The transition resistances in the tissue and the electrical power that occurs thereon only play a subordinate role.

As a result, current marks develop in both cases: severe burns at the entry and exit points of the current in the skin.

literature

  • Franz-Josef Kretz, Jürgen Schäffer: Anesthesia, intensive care medicine, emergency medicine, pain therapy . 4th edition. Springer, 2005, ISBN 978-3-540-25698-4 .