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I found a Darwin award story claiming that someone was killed by pushing the leads of a Simpson 260 into his skin in ohmmeter mode. Furthermore, the story claims it is based on an unnamed US Navy Safety Publication.

What makes me skeptical about this story is that most multimeters limit current on their ohmmeter setting. I can barely feel anything by putting a generic $4 DT830 on my tongue on its lowest ohmmeter range (200 ohms) and I feel virtual nothing on its higher ranges, but I can certainly feel a bare 9V battery much more strongly that way.

So is there any secondary corroboration of this improbable death by ohmmeter/multimeter story? Also is anyone familiar enough with the Simpson 260 that would make this story more (or less) plausible? Myself looking at the schematic from the manual linked above, makes me think it even less plausible

enter image description here

(Click to enlarge) At one setting the voltage is only 1.5V, at the other end it is 7.5V, but with a large series resistor (>100Kohm). I've heard of exceptional cases where people have died from 12V car batteries, but not from 1.5V.

For a human body immersed in water, which greatly lowers skin resitance, the typical figure for whole body resistance is 300 ohms, so 30 V is given in that paper as the voltage needed to cause ventricular fibrilation in water. Granted, skin puncture may lower than even further, but how much further?

Another paper claims that

In the case of transverse direct current shock (e.g. from left hand to right hand), the occurrence of ventricular fibrillation is unlikely. Nevertheless, when such shock is sustained for a long time, high shock currents may lead to reversible cardiac arrhythmia, burns and loss of consciousness, which in the absence of appropriate medical aid can result in death.

Ventricular fibrillation with DC shocks usually occurs in the case of longitudinal current flow in the body. The value of the threshold shock current that causes fibrillation is two times higher for downward currents (negative potential of feet) than for upward currents. According to the IEC report [15], with shocks lasting more than 0.2 s, the value of the direct current liable to cause fibrillation is much higher (almost fourfold) than that of an alternating current and is equal to 150 mA–200 mA.

These don't quite jibe with dying from 1.5V DC source, hand to hand. Of course, unlikely doesn't mean it can never happen, but claims of extraordinary events require substantial evidence to be credible.

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    @DanielRHicks: Ok, if you're convinced it happened (somehow), write it as an answer. And let's not sidetrack this question with microshock stuff anymore, I've written a separate question about that: skeptics.stackexchange.com/questions/39871/… – Fizz Oct 31 '17 at 1:26
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    The one piece I'm missing for an official answer is some credible info on the body's internal resistance. (Maybe I should get out my old VOM and check it!) – Daniel R Hicks Oct 31 '17 at 1:31
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    @Baldrickk - No, "internal resistance" is resistance internal to SOMETHING. In this case the resistance of the body itself, after you get through the skin. – Daniel R Hicks Nov 6 '17 at 22:18
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    @DanielRHicks no, an ammeter is, when taken as a single component, a power source, so it has an internal resistance. – Baldrickk Nov 7 '17 at 13:58
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    @laptop2d - Yes, but a standard ammeter is in no way a "power source". – Daniel R Hicks Oct 31 '18 at 23:34
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If the current has a direct pathway to the heart (e.g., via a cardiac catheter or other kind of electrode), a much lower current of less than 1 mA (AC or DC) can cause fibrillation

Source: https://en.wikipedia.org/wiki/Electrical_injury

The second contact mechanism involves a person in the water being in an electric field because of an energized conductor that is in the water. For example, an electric heater connected to the hot wire of the 120 V AC outlet falls in the water. The grounded drain is close to the person's shoulders, whereas the heater is near his or her feet. This gives a voltage difference of 120 V AC from shoulders to the feet. With a total body resistance of 300 Ω, 360 mA flows, more than 3 times the amount needed to give ventricular fibrillation.

Source: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2763825/

So one way to find out what voltage could kill you internally would be take 1mA*300Ω=0.3V or 10mA*300Ω=3V Which a millimeter could easily provide either, especially the cheap ones (most multi meters have 6 or 9V).

The other problem is the skin, since it is much more conductive, most of the current will be lessened, as soon as you break the skin the current will take the lowest resistance path. most likely through the heart if your going from hand to hand.

The central argument of this answer is theoretical in nature. We do not allow answers based uniquely on common sense or pure logic. Answers which are wholly based on a theoretical model are generally downvoted and may be deleted. See FAQ: What are theoretical answers?

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    I would make a minor edit to say "Yes, because it is the amperage that kills you." – Dúthomhas Aug 28 at 3:44
  • "So one way to find out what voltage could kill you internally would be take 1mA*300Ω=0.3V or 10mA*300Ω=3V [...]" - I get why you use 1mA in the first equation (you have a source at the beginning citing 1mA for direct heart stimulation) - but where do you get the 10mA? Your other excerpt is going on about 360mA being 'more than 3 times' the deadly amount, so ~100mA would be deadly acording to that source (which would work out to 30V in your equation, which is in the ballpark of the cutoff for 'low voltage' stuff that can legally be done in, e.g., schools in Germany without special precautions. – bukwyrm Aug 29 at 7:29
  • @bukwyrm, were talking about under the skin, which means probes though your skin. Skin is in the kiloohms range and varies from person to person. Once because the skin resistance drops and the likely hood of current killing you increases. IPC requirements define hazardous voltages to be more than 60V, but this is assuming the voltage is applied in the outside not inside the skin – Voltage Spike Aug 29 at 18:49
  • @VoltageSpike the skin resistance was skipped as soon as you took 300 Ohms for human resistance - got it. Regardless of how the current is instigated (kV to negate the skin resistance, or tens of V without it): The deadly thing is the amperage. 1mA(according to your source) through the heart : deadly; 100mA (according to your source) through the whole body (thus a smaller amount through a path through the heart and other possibly important tissue) : deadly; Using those amperages, you can go back and compute the neccessary voltages: e.g. 0.3V and 30V at 300Ohm - but whence the 10 mA for 3V? – bukwyrm Aug 30 at 6:36

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