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When I googled about skin resistance I find people mentioning values as low as 500ohm but usually around 10-100kohm. When i measured the resistance of my own skin by putting the probes on the inner side of my forearm(just below the wrist) with 1-2cm between the probes, the resistance is so high my multimeter can't even measure it. I tried wetting my arm with some saliva and got a resistance above 1000kohms, and yes, I mean 1 million ohms. So to assure that I didn't misinterpret the numbers on the multimeter, I measured a 100kohm resistor on the same setting and it showed me "100" and then my skin again and it showed me about "1487". Is this possible?

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    \$\begingroup\$ There's no such thing as "true value" for the skin resistance, as it varies with humidity (as you discovered), with the amount of dirt, grease, thickness, etc. \$\endgroup\$ – a concerned citizen Sep 18 '18 at 11:07
  • \$\begingroup\$ The skin insulates your internals from all kinds of outside things, including electricity, to a certain degree. If those probes were instead poked through the skin, the reading would be much lower (a lot more conductive.) High-voltage electricity can easily "defeat" the skin's electrical insulation, much like a very sharp probe, which makes it dangerous. \$\endgroup\$ – rdtsc Sep 18 '18 at 11:21
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Yes, it is possible. Now try measuring your skin resistance with a larger area contact. Also bear in mind that when it comes to mains (high voltage) electrical shock the skin is not just a simple passive resistor. It can break down, and when that happens you are looking at the resistance of the blood stream and fat/muscle tissue which is considerably less.

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  • \$\begingroup\$ By breakdown do you mean that it would get burnt or something of that kind? So breakdown would be something I would feel when it happens? \$\endgroup\$ – Elec0 Sep 18 '18 at 12:20
  • \$\begingroup\$ In approximately what range would the resistance of the insides (blood, fat/muscles) be if the skin broke down? \$\endgroup\$ – Elec0 Sep 18 '18 at 12:25
  • \$\begingroup\$ @Newbie "The NIOSH states "Under dry conditions, the resistance offered by the human body may be as high as 100,000 ohms. Wet or broken skin may drop the body's resistance to 1,000 ohms," adding that "high-voltage electrical energy quickly breaks down human skin, reducing the human body's resistance to 500 ohms" \$\endgroup\$ – Dirk Bruere Sep 18 '18 at 13:13
  • \$\begingroup\$ @Newbie 6mA across the heart can kill. \$\endgroup\$ – Dirk Bruere Sep 18 '18 at 13:14
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    \$\begingroup\$ @Newbie A current of 6mA through the heart can kill a person. \$\endgroup\$ – Elliot Alderson Sep 18 '18 at 13:19
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Yes, it's possible. There is no such single universial thing as true value of skin resistance.

Real skin resistance depends on a lot of factors, including how sweaty the skin is, how calloused, how clean, etc.

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