Can someone please inform me the required minimum amount of DC voltage and current to startle a human being? The surface of contact would be dry skin.
To find out the resistance of dry skin by a multimeter. I believe it is greater than 300 K Ohms.
It varies. You can easily feel 4.5 VDC if you touch a battery to your tongue, for example. I think the generally accepted "safe" voltage is 30 volts or less, on dry skin, although even the 48 volts of analog telephones (voltage goes up when the phone rings!) seems safe to me. I don't feel it, touching the contacts with my fingers.
These are rough guidelines. The voltage is what creates the current flow, through the impedance of the skin, and the current flow is what you feel as a shock. It takes a few mA, 5 mA or even less, for current to be felt.
https://www.osha.gov/Publications/3075.html
If you search online, you'll find many different values for impedance through skin. It depends where you take the measurement and on the person. Dry skin conducts less than muscle tissue, for example. But it's easy enough to do some rough numbers.
It's no mystery that people can get a big jolt when touching 120 VAC. Okay, so let's assume that 120 V gives you a painful shock that you can pull away from. That would imply maybe 10 mA of current flow, possibly more, but not a lot less. By the table in the link above, much more than that, and you're in the "cannot pull away" territory. So this seems like a realistic data point.
Z = v / i
The resistance of dry skin, by this reasoning, cannot be a lot higher than 12 Kohm. I'm only pointing this out because if you use a figure of 100K-600Kohm, as one often sees quoted, a 120V shock would barely be felt. Well, we know that's not the case! If the resistance of human skin were 100 Kohm, a 120V shock would consist of only 1.2 mA, which would barely be perceptible. Even dry skin is likely to be less than 100 Kohm.
Voltage,Resistance offered(current) are not that important than how circuit is completed, as line man working on DC line are advised to work with one hand, as circuit should not be completed via heart......
Tongue Resistance 40K Ohm, finger resistance 11.6 MOhm, Sole resistance 22 MOhm, Forearm Resistance 6 MOhm.
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