16-year-old survives 25,000V blast

[Rob Williams]

Sam was retrieving a rugby ball on the bridge near his home in Wigan on Thursday evening when a charge leapt from overhead powerlines into the steel toecaps of his boots.

He was knocked unconscious by the fall and all his clothes were burned off.
After paramedics arrived Sam regained consciousness and managed to phone his mother Ann.

Miss Cunningham, 40, a health care assistant, said: "I got there within a couple of minutes and all his clothes had been burned off, he was shaking from head to toe.

http://www.dailymail.co.uk/pages/li...in_article_id=564383&in_page_id=1770&ito=1490

 

[madmat]

Damn those steel toed boots.

 

[THUMPer]

its the amps that kill ya. haha

 

[Rob Williams]

Is it common in some places for people to wear steel-toed boots when not working? I've never heard of it, nor know anyone that wears them on a regular basis.

 

[madmat]

Back in the day when I was a lad (literally, 10 or so) I seem to remember the badasses of the neighborhood taking steel toed boots, cutting all but about 1/4" of the leather covering the toe cap off and polishing the toe caps. This did indeed look pretty impressive but it also gave you fair warning that should they kick you that they'd put a pretty bad hurting on you.

 

[slugbug]

Ever touch a faulty spark plug wire and get a shock? Car ignition coils can give off 40,000 volts or more, but are low in amperage so they won't kill you.

 

[Kougar]

As the article said... kid must of been within a foot or two of the cables to trigger a discharge. Not smart!

 

[current2]

As the article said... kid must of been within a foot or two of the cables to trigger a discharge. Not smart!

Much closer than 1' I would say!
In HV engineerig 25000 V is a relatively small voltage.Since this is AC voltage ,peak is about is about 37000 V (assuming nominal ~25kV).That voltage level would be capable to jump only over gaps 1/2" to 2" wide (depending on the geometry of electrodes and the state of air conditions like temperature,moisture etc.).
Don't believe articles and technically poorly educated journalists.They confuse volts and watts,and sometimes even inch and foot .
Also ,the steel toed boots has little to do when we are speaking of triggering the discharge.They just present good grounding when the discharge already started (matter of fact I tend to belive they saved the boy's life!).
However,it leaves an intertesting subject of debate what actually happend and what triggered discharge if he was more than one feet away from the power line.Maybe he picked some conducting strings of grass ,spider webs full of conducting dirt or something...

 

[current2]

I should also add that few years ago my father investigated the electrocution of the person found dead on the tram bridge.It turned out that he pissed from the bridge to the power line several feet away.He had closed the gap in this way (urine is an excellent electrolite).He was drunk doing that.Line voltage in this case was only 600 V ,but doesn't mean anything.

 

[moon111]

I should also add that few years ago my father investigated the electrocution of the person found dead on the tram bridge.It turned out that he pissed from the bridge to the power line several feet away.He had closed the gap in this way (urine is an excellent electrolite).He was drunk doing that.Line voltage in this case was only 600 V ,but doesn't mean anything.

I've read this about a Darwin Award candidate:

(I've condensed it from the following source: http://www.fuzzydog.com/mscdarwin.htm)

..a man who was forlorn after a recent spat with his girlfriend needed some fresh air to clear his head and decided to climb a (hydro) tower. He stopped for a 6 pack to help clear his thoughts. After 5 beers, he needed to do what people often need to do after 5 beers. It being such a long hike down, he unzipped and did his business right there off the tower. Depending on conditions, 115,000 volt lines, like those supported by the tower, could shock a person as far away as 6 feet. When the man "wizzed" near the conductor (wire), the power arced up his "stream" (urine is an excellent conductor of electricity), traveled up to his private parts, and blew him off the tower. The guys at the power company noted a momentary outage on this line and sent repairmen to see if there was any damage. When they got to the scene of the accident, they found a very dead person, his fly down, what was left of his private parts smoking, and a single beer left on top.

 

[current2]

Depending on conditions, 115,000 volt lines, like those supported by the tower, could shock a person as far away as 6 feet.

Well,the insulators between pylon tower parts (which is grounded) and
it's power lines for the nominal voltage level of 220,000 V are only ~6 ft long.What do you conclude from that about shocking person 6 feet away by 115 000 V line? It must be a really bad weather
But if you want to enjoy more "masterpices" of the journalism regarding Sam C's accident I recommend this (drink a beer prior and after the reading):


http://www.newstin.co.uk/tag/uk/56065755

http://www.wigantoday.net/wigannews/Teenager-survives-terror-fall.4047252.jp

 

[Rob Williams]

Thanks a lot for the info current2, it's appreciated! I have to admit I actually chuckled at the urine story... as sad as it actually is. I had no idea at all that something like that was possible. Obviously, it doesn't seem like many people do.

Good links as well... goes to show that newspapers tend to write whatever they feel like. The first one is even worse off... it wasn't noted that he fell on anything. Or perhaps it was true and the story I linked to wasn't.

 

[Merlin]

Was Busted

Thanks a lot for the info current2, it's appreciated! I have to admit I actually chuckled at the urine story... as sad as it actually is. I had no idea at all that something like that was possible. Obviously, it doesn't seem like many people do.

Good links as well... goes to show that newspapers tend to write whatever they feel like. The first one is even worse off... it wasn't noted that he fell on anything. Or perhaps it was true and the story I linked to wasn't.

BUSTED

Mythbusters showed that it was possible, but not likely...it's the short distance that was plausable

:techgage::techgage: Merlin :techgage::techgage:

 

[Rob Williams]

BUSTED

Mythbusters showed that it was possible, but not likely...it's the short distance that was plausable

:techgage::techgage: Merlin :techgage::techgage:

Well, that was a train track, wouldn't an actual power station have more "oopmh" to allow a larger distance?

 

[MakubeX]

So he was playing Rugby with steel toe boots? Maybe the electric shock was karma for breaking the shins of so many players.

 

[current2]

BUSTED

Mythbusters showed that it was possible, but not likely...it's the short distance that was plausable

99 times nothing would happen ,but 100th time..
When the *stream* of urine remains continuous ,it might be fatal.That poor man was found dead ,with unzipped well hmm .. Firstly they thought it was an ordinary heart attack,but authopsy confirmed the electrocution (no eyewitneses what happend).
He was at least 4 ft away from the 600 V line which supplied trams with electricity.
I would be much more surprised by the 115 000 V electrocution story.
From the story it appears ,that victim of "the pissing electrocution" must had been much further from the HV lines.And longer the urine stream ,more intermittient with more "gaps" it is (especially if it is windy ).

 

[Kougar]

I've seen a Modern Marvels show on how they service overhead powerlines... the bigger ones they use a chopper to reach, and they specifically must trigger a discharge to ground the chopper to the cable before the guy can start working on them. A foot or even two feet depending on weather was the arc zone on the bigger lines.

 

[current2]

I've seen a Modern Marvels show on how they service overhead powerlines... the bigger ones they use a chopper to reach, and they specifically must trigger a discharge to ground the chopper to the cable before the guy can start working on them. A foot or even two feet depending on weather was the arc zone on the bigger lines.

I've seen that in real enviroment in person

 

[current2]

Hmm guys,anybody here from UK /London-Liverpool area to investigate more detaily what really happend in the case of Sam Cunningham?
The most important is to find out how far was his shoe from the 25 kV line when the arc was triggered.BTW,if people wonder how he could survive they should read this report:
http://www.medbc.com/annals/review/vol_7/num_2/text/vol7n2p91.htm

Usually they survive such electrial blasts & shocks !But most of them with long terms damage:burned skin and tissue being the worst.Sam was just lucky that he avoided deep burns.Therefore,when he recovers give him a call,ask him .Maybe he will remember where ,how ,and how far from the power line he strood.
And seems that there were some eyewitnesses (his friends).
Ask,search.
(Just don't ask that dumb policeman who said the lines were on 750 000 V ).

I do have a refference materials dealing with dielectric strenght of air gaps under various circumstances ,at sea level altitude .The results of the tests with AC,DC and switching pulses ;with rod-rod gaps,sphere-plane gaps,needle- plane gaps...And under the most favorable conditions with temperature 25 C° and high humidity ,a needle-plane gap is expected to be the of the weakest "strenght".It breaks down(but it's also statistically highly unlikely) when the peak voltage is 40 kV when the electrodes are 5,5 cm appart.This is just little more than 2".
To break down 12" it's expected to happen never at this voltage level.Not even in million years.

 

[Merlin]

Well, that was a train track, wouldn't an actual power station have more "oopmh" to allow a larger distance?

It's the amps that get you, I was an electrician while going to college to be an electrical engineer. ( had to quit for raising family )
High tension transmission ( Step up tansformers ) lines have very little amps, the Step down transformers transform the high voltage down and the amps ( current ) in % ...go up.
Amps are what kill you.
You can survive a high volatge burst, but the path that the electricity traveled in your nervous synapses are burnt out. It just depends on what path it takes.
A country boy can survive

:techgage::techgage: Merlin :techgage::techgage: