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Voltage vs. current
It is a matter of annoyance to me that people say things like "It's not the volts, it's the amps that kill you." Seeing something like:
points out, I think, a great deal of confusion in this matter. Line current is not important; the current through your body is important. Line voltage is important, as it in part determines the current through your body.
I don't really know how to fix this article so it is factual, but doesn't rely too heavily on explanations of Ohm's law, etc. I also don't think it should look like a compromise between the "voltage" and "current camps", since there aren't really two points of view here. Idea? ] 23:38, 28 Oct 2004 (UTC)
Upon further review, I'm not sure about a lot of the information here. For example, most other sources I find list currents about 10 times here for each of the effects (about 10-15mA for unable to let go of wires, hundreds of mA for fribulation). And to say that the voltages in homes are a deadly combination seems a bit alarmist. I'm going to do some more research before touching this one. ] 00:01, 29 Oct 2004 (UTC)
Since mains current is AC, though, it cannot cause your muscles to contract. The alternating polarity will cancel out and you won't hang on. A strong DC current can make your muscles contract around the electrical source. Adam850 09:23, 26 January 2005 (UTC)
That's false. AC certainly can cause contraction of muscles. Muscles aren't motors, and the way in which electricity disrupts normal neuromotor control isn't a matter of superposition. --Blair P. Houghton 04:26, 28 Jan 2005 (UTC)
I removed the dispute notice as no one has edited this article or said anything on the talk page for weeks and weeks. If anyone still has a problem with the facts as presented in this article, take the usual NPOV approach and cite sources to support the sides of the argument as presented by various schools of thought on the matter. — Trilobite (Talk) 19:40, 29 Mar 2005 (UTC)
Electrocution - Electric Chair & animal use
Isn't it a bit POV to claim that throughout the world 'the Chair' is viewed as 'inhumane'? Isn't it rather the case that it's gruesome and sickening to watch (a rather different point). There is quite a bit of evidence (see Dr Grandin's animal husbandry web site) that an electric current of an amp or two is an efficient way of inducing unconsciousness in a large mammal, provided the current path is through the brain. (There was also at least one 19th century US medic who self-experimented (!) on the level of current sufficient to induce unconsciousness)80.177.213.144
True (well more or less - though it wasn't the reason we in the UK abolished the penalty many, many years ago) - but in the present context, irrelevant :-) 80.177.213.144
Fibrillation
The 100 to 200 mA region for fibrillation agrees with my best recollection (ARRL handbook in days of valves/tubes?), but where's the evidence that such fibrillation 'tears the tissue' and 'destroys the heart' - I though the whole point about fibrillation was that it _could_ be stopped, by a large electric shock, from a defibrillator - though of course time is of the essence, because a heart in fibrillation pumps no blood. Linuxlad 01:55, 25 July 2005 (UTC)
Electrocution
I would like this article to define electrocution as how many amps/volts pass through the heart.
If you're asking how many "amps/volts" it takes to cause death, the answer is... it depends. The number varies with the individual person. LadyPlural (talk) 22:57, 24 December 2007 (UTC)
High- vs. low-voltage shocks
Breaing in mind we only respond to the current, why is it that hv shocks tend to hurt (sting) more but low voltage ones tend to 'shock' you more(ie take your breath away)?? Or is it just me? Any answers/ sugesstions?--Light current 02:58, 31 October 2005 (UTC)
Could be that the bad shcocks Ive had have been from 240v from left hand to leg (or left hand to right hand) and those are very shocking! They take your breath away. Its also possible that these mains shocks are longer in duration than you might get from a HV capcitor of a few pF. THe HV shocks are probably limited to much less current, and if they do not pass thro the chest, just tend to sting the entrance / exit points. Maybe we need to mention also the max safe amount of stored energy. I think its 2J.--Light current 18:59, 3 November 2005 (UTC)
Impedance of the human body
I just hooked up an ohm meter to my body and it showed me these results:
This data is not made up, I really did conduct this experiment just now. According to these numbers and using Ohm's law, how much current would the body be capable of letting through? Also, can someone verify these numbers? Caution: This should only be done by grown ups and NO CHILDREN. Thanks!
There isn't much point in 'verifying' the numbers. Try it again on a different day or using smooth and then rough electrodes or on skin recently washed with soap and then after washing with detergent or with a different test current or varying a multitude of other factors. The numbers will vary. The test with different test current illustrates that the body is not an ohmic material. The most important point is that the source voltage is not a useful guide to the degree of risk. The current that flows is a very rough guide, though the effects vary in an individual over a wide range unless the conditions are very carefully controlled. Controlled conditions are of course not available (except perhaps to an executioner or torturer) so one should treat any voltage over 24 volts as though it is potentially lethal. Electric shock is not the only hazard, even lower voltages can be dangerous if they cause arcing or heating. treesmill 00:55, 27 December 2005 (UTC)
This is very cool. Especially interesting is the 25K Ohm reading between my wet lips. My faith in the veracity of this article is restored. And I really appreciate your input!
I shall now go back to playing Grand_Theft_Auto_III (man, I love that game!!!).
This is all assuming the body is a simple resistor though. The figures actually make it non-linear with respect to voltage, in the same way as other insulators or semiconductors - see this link which I found off Google. So the impedance at 110V is much less than the impedance at 1.5V, and as a result the effects are going to be more severe than your measurements suggest.
So everyone here is getting dry skin measurement way above 200k, yet, the article calls out 10k. And, with no citations! WTF? Also, the article states as low as 1k. From what I'm hearing in the discussion, you need to pierce the skin. Is there any data on the distribution of resistance across population under controlled conditions?
Update: Saw the ePanorama link. I hadn't even considered contact area (assumed <1cm 2 ). Question for the Australian Standard AS3859-1991, who is going to have 100cm 2 of contact area?
Update2: I have heard that current flow through skin causes perspiration. Is this true? Could that explain the changes in resistance (higher current, more perspiration)? The footnotes state that the resistance at low voltage halves in the presence of conductive solutions.
Also, who touched 1000V with a large contact area, and long enough to make a measurement? Eet 1024 (talk) 00:57, 26 January 2008 (UTC)
The resistance values in the article are ridiculously low every value i've ever taken has been in the megaohms. And consequently so are the claims that 32V can kill you. maybe if you plugged the terminals directly into your veins or something but def not through the skin. I work on electrocution circuits for a security company as a part-time job. The circuits we develop give out 10kV pulses and def won't kill you. The police tasers normally do 30kV - 50kV and have never killed anyone (not in this country anyway).
As for those values taken with wet lips etc you aren't measuring the resistance through your skin your just measuring it through the moisture on the surface of ur skin to another point on the surface. —Preceding unsigned comment added by 203.211.76.57 (talk) 10:31, 28 Oc
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