Some additional bits and pieces.
IO540
Just checked clearances in the UK supply industry are: -
up to 33kV .8m, 132kV 0.7m added to these is an application factor dependant on the work involved e.g. when climbing a pole add .3m, working platform level on a pole add 2.1m. I'd added an extra .1 earlier - coward. these apply in all conditions and are err on the side of safety.
Plasma
Probably the major factor, try putting your bare hand near a welding arc see what happens (
definately don't try this at home). As you say a lot of data is not analyitical. We are advised to wear cottton clothing (synthetics melt into the skin - seen this on advice for air travel as well) and are issued with Nomex Arc-Resistant clothing. This is tested, in Canada, to 25kV. we are told that if worn over no other clothing body protected from heat effects of arc.
As B.M. says depends on Ohms law voltage/resistance = current. Whist the 50mA figure I quoted earlier is accepted its only an average, similarly body resistence varys on the individual and on external e.g. weather conditions.
Deep burns seem to be one of the major causes of severe effects. I am sure we all have burnt the odd finger etc. over our lives these cause a blister and swelling. Current flow through the body causes the same under the skin E.G. to muscles etc. these cause limbs to swell and can only be relieved by surgically cutting the skin or ulimately amputation.
Curiously, I used to think that you are probably more likely to be electrocuted by a household voltage of 110/220V
B.M.
actually not far wrong, far more killed by electrical shock in domestic incidents at lower voltages than work related at higher voltages. Also at lower voltages the arc & burning effects are less likely and less evident. At higher voltages the shear ammount of burns can hide the fact that the heart was affected by electrical shock, it could have been physical shock!
I would expect the skin to be penetrated in two spots
If one or both them spots are fingers or toes you can also expect to lose them, heating effect of current flow through a resistance. In most UK systems the live to earth current can be up to 1000A (we limit it)
Some anecdotes
Early 80's a worker came into contact with an 11kV line whilst erecting an aluminuim flag pole at an agricultural show (about 15 miles from where I'm sat) I wasn't involved with the investigation, too junior at the time, but he survived but lost a number of toes in the incident and sufferd burns to the palms of his hands.
6 months earlier a 14 yr old killed erecting a CB aerial contact with an 11kv line.
A worker wheeling a portable scaffold came into contact with a 132kv line, survived, current flow burnt off parts of limbs, deep burns led to amputation of lower arms and legs. Appeared on some safety fims telling his story. Sadly I have been told he eventually took his own life.
90's A mentally ill patient left a local hospital deliberately climbed a 132kV pylon, the barbed wire and climbing guard didn't bother him, leant out and lost his life with contact with live conductor. The steelwork apparently was a mess afterwards.
Only a few days ago, a kid got killed here in France, climbing on top of a goods wagon - to recover a football IIRC. Drew an arc from the live 25kV overhead catenary .... Got quite a lot of TV coverage, to alert as many people as possible.
Christaan J
2 weeks later a "drunken" young person climbed an 11kv pole in southern england same result.
Don't forget also on high structures if the current doesn't kill you the fall might!
On that note and slightly lighter, in the 70's a person in the Bristol area decided to take his life by climbing a 400kV pylon, climbed the structure, climbed down the insulator string ans sat on the conductors - nothing happenned. Decided he had rubber soled shoes on so climbed back up the insulayors took them off and climbed back down - nothing happenned. was eventually rescued from the position.
It was a dry day the insultator strings are long enough not to be bridged when climbing down them.
On returning him to ground level a remark was made he would have been better jumping he hasd been at 100m agl