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Hello Tracey, I'm sorry to hear about your son, and I hope he makes a speedy recovery. By no means am I an expert in utility procedures and accident investigations. I can describe the properties of high voltage AC and suggest some possibilities as far as what MAY have happened. First, 11 kV does not "jump" very far - typically less than an inch. Objects 1 meter away from a 11 kV line would not be in danger of having sparks jump to them from the line or of being pulled toward the line via electrostatic attraction. However, if momentary contact is accidentally made between the HV line and a partially grounded object, a conductive arc will form. The resulting arc may extend for a considerable distance, and the greater the current that flows through the arc, the longer the arc can become. Once the arc is initiated ("struck"), an 11 kV power arc can easily extend for feet, or even tens of feet. But the conductive object first needs to be within an inch or so of the HV line to "strike" the arc. An ungrounded electrically conductive object can become "charged", acquiring a significant voltage by simply being in close proximity to a high voltage power line via a process called induction. Induction can also cause a relatively low "charging" current to flow between the conductive object and ground when a conductive path is provided. This conductive path could be a person simultaneously touching the object and the tree, since the tree's moist tissues provide a fairly good connection to ground. Although the magnitude of the charging current is usually not fatal, it can be sufficient to startle the person or even cause sudden involuntary muscle contractions that may "throw" the person some distance. I obviously don't know the details about the platform, and the position of the HV line, your son, and the tree. However, if the platform was made of metal and was electrically insulated, it may have become electrically charged through induction. If the platform was a "cherry picker", the tires of the vehicle may have insulated. Once your son began descending from the platform, he may have received an electrical shock as he simultaneously touched the platform and the tree. If this shock was of sufficient magnitude to cause a sudden contraction of his leg muscles, he may have involuntarily "jumped" upward, causing him to then make more deadly contact with the HV line. The simultaneous contact with the tree and HV line would result in significant electrocution injuries. Again, this is only one of many possible scenarios. Another possibity is that one of the tree's branches brushed the HV line, causing a sequence of events which electrically shocked your son, causing him to involuntarily "jump" to the HV line. In any event, I hope your son makes a rapid and complete recovery. -- Bert --
: Several months ago my son was accidentally electrocuted by an 11kv
: powerline outside our house, and sustained serious injuries.
: The companys investigation claims he 'touched' a hv conductor, yet he
: still insists he was atop a tree on a safety platform and was getting
: DOWN from the platform to the tree when the shock occurred and never
: touched or climbed anything.
: When i saw him he was about 6m in the air and about 1m above the
: platform he claims to have been touching is this posible? Does anyone
: know how far hv power can arc and if its capable of pulling him up in
: this manner?
: all help appreciated,
: tracey
:
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