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A solar power book makes this claim:

A low voltage system can cause major problems simply because of the huge current that a 12v battery can generate: in excess of 1,000 amps in short burst can easily cause a severe shock -- and even death of serious injury in some cases.

(It goes on to say that a 12v battery can also cause a fire in the case of a short, something I think is undisputable.)

I've heard of these alleged deaths from 12V batteries before, but I can't recall the source right now. The aforementioned book is something I found in 3s on google. Here is another one:

If you have wet, salty hands and grab hold of the terminals of a 12 Volt battery, there is a significant danger of severe shock or even death in certain cases.

Anyhow, my question is: where's the evidence? I'd like to see some case reports (even if just in the mass media) that exemplify this death by electroshock from 12v battery.

Also, let's exclude ingesting batteries, because then even 3V can kill you (and probably 1.5V as well, but I can't a find a case right now) through internal hemorrhaging etc. caused by the electrical discharge burning tissue. The usual context of the claims about (high-amperage) 12v batteries (car, solar power etc.) typically precludes the swallowing scenario.

  • It is the current that kills you.This question should be in physics or electricals. – Grasper Oct 31 '17 at 11:53
  • @Grasper: it's not a theory question. It's one about actual occurrences of events. – Fizz Oct 31 '17 at 12:17
  • @Grasper I'd argue it's more biology than physics or electronics. Generally physicists aren't concerned with how lethal things like this are. Regardless, it may be "the current that kills you", but it's definitely possible to estimate the resistance of a person and therefore determine the expected current given an applied voltage. – JMac Oct 31 '17 at 12:28
  • electronics.stackexchange.com/questions/9222/… possibly related (also suggests differently than the claims here). – JMac Oct 31 '17 at 12:28
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    Very much related: How much voltage is “dangerous”? on Electrical Engineering. – a CVn Nov 1 '17 at 9:08
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No, you can't get an electric shock from a 12V power source.

The Underwrites Laboratory which regulates product safety in the US defines "hazardous voltage" as

Hazardous Voltage Any voltage exceeding 42.2 Vac peak or 60 Vdc without a limited current circuit

http://www.cui.com/catalog/resource/power-supply-safety-standards-agencies-and-marks.pdf.

Anything below this is considered Extra Low Voltage and product designers are not required to provide any type of access protection for the user. That why it is perfectly legal to have batteries with exposed contacts.

Interaction between electricity and the human body is quite complicated (See for example https://en.wikipedia.org/wiki/Electric_shock) but in general the main factors are amount of current and time of exposure. Given the electrical resistance of the human body, 12V are simply not enough voltage to drive significant current through a human. In fact, in almost all cases you won't feel anything at all.

You could potentially construct scenarios where it becomes a very noticeable effect: e.g. bring the the terminal close together and stick your tongue in there. This may fit someone's definition of a shock.

This being said: Big Batteries or solar sources contain a lot of energy and are quite dangerous if being abused.

It's entirely possible to make them over heat, create a fire, explode, cause severe burns, acid damage & burns, mechanical body damage etc. They should be treated with respect and care. There are significant dangers if mishandled, but electric shock is not one of them.

  • Extra low voltage was taught to me as 24V DC, wet or broken skin would allow shocks and maybe death at lower voltages. – daniel Oct 31 '17 at 17:00
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    Note that there are rare cases where this can go out the window: low-impedance connections like medical jelled electrodes or skin penetration, if coupled with pre-existing ticker timing issues can vastly change the voltages required. – 0xDBFB7 Nov 1 '17 at 2:31
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    An accurate method of determining danger is to use the energy delivered to the body. The typical standard threshold is, IIRC, 100 mJ. A millisecond 10kv pulse to the heart, as in tasers, delivers very little energy, for instance, where such a pulse would typically break both the voltage and current limits. – 0xDBFB7 Nov 1 '17 at 2:34
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    This answer from electrical engineering seems to disagree with you: electronics.stackexchange.com/a/19120/101831 Whether you believe the theorizing / anecdotes in that answer or not, the first line of your answer should probably changed to say that 12 V can't deliver a lethal, electrical shock, because 12V can definitely give you a non-lethal shock. – eirikdaude Nov 2 '17 at 9:56
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    @Acccumulation: I just took a 9V battery, made the contacts nice and wet and pressed them against my chest in the heart area. I'm happy to report that A) I am still alive and B) I didn't feel anything at all. I've worked a lot with power electronics and got my fair share of unpleasant encounters, however 12V or 9V are simply not in this class. Disclaimer: I'm a trained and degreed professional, don't fuzz around with electronics unless you know what you are doing – Hilmar Nov 4 '17 at 16:20

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