Browse Definitions:

electric arc

An electric arc is a visible plasma discharge between two electrodes that is caused by electrical current ionizing gasses in the air. Electric arcs occur in nature in the form of lightning. 

With proper control, electric arcs can be harnessed and used industrially for welding, plasma cutting and even certain types of lighting such as fluorescent lighting where a high voltage ionizes the inert gas within a glass tube; the flow of current across the ionized gas liberates visible light. However, for every harnessed electric arc there is an unwanted arc. For example, poorly installed (or poor quality) electrical switches, electrical circuit breakers and other electrical contact points are susceptible to these undesired arcs as contacts are opened and closed.

This was last updated in May 2012

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Hi Margaret.

Thank you for the definition of electric arc flash.

I have found research that suggests arc flash can reach temperatures of up to
20 0000 Degrees Celecius and kill at a distance of 3 meters.

Workers should protect themselves by making use of the correct personal protective clothing and equipment for electric arc flash.

Have a look at

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