Arc jumps
• Current arcs ( jumps ) from the conductor and passes through the worker , through part of the tree , or through tools or equipment .
• Injuries and fatalities can be caused without the worker necessarily contacting the conductors .
• The risk of arc jumps will be significantly increased if uninsulated tools or equipment are used , and in some weather conditions , such as high humidity , rain or line movement in wind .
Exposure to arc flash
• If the worker is in close proximity to an arc flash , they can be injured by the heat , noise or debris , without the current passing through the worker .
• The arc reaches extremely high temperatures and may cause flash burns to workers who are well clear of the conductors . In addition , there may be a pressure wave , flying debris and hearing damage . Arc burns cause more fatalities in the electrical industry than electrocution .
• Arc flash can occur during tree work operations when conductors are accidentally brought closer together , for example during rigging , high winds , or by the use of non-insulated tools .
Step potential
• Step potential occurs when current from conductors enters the ground .
• If a worker stands with their feet separated , the path of least resistance for the electrical current may be to flow up one leg and down the other .
• Step potential risks may occur after electrical faults , when wires are down , or when equipment becomes energised .
• Where risks of step potential exist , it is critical that no difference in step potential is created . When near energised equipment or fallen wires , exit the area by either shuffling ( keeping both feet together ) or hopping ( keeping both feet together ). Hop or shuffle at least 10m away from the conductor before walking further away .
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