nerve locator

[Hero999]

I don't think 200V was a joke, as Willbe said you need a much higher voltage to get a shock, with dry skin I can't even feel voltages as high as 70VDC and the lowest voltage I've had a tingle from is 30VAC (which has a similar shocking capacity as 70VDC) but I had wet hands so it was my fault. I would go even higher than 200VDC, I'd suggest even 500V again as long as the current is limited it's perfectly safe.

I wouldn't recommend building this thing for anything other than educational purposes and would strongly discourage you from allowing it to be used on patients.

 

[Willbe]

I wouldn't recommend building this thing for anything other than educational purposes and would strongly discourage you from allowing it to be used on patients.

Cell damage on a molecular level could take 20 years to show up, probably as a cancer.
Speaking of electric currents, I'm also wondering when "the chickens will come home to roost" with all this cell phone usage; half the field energy goes into the user's head.
Some think that there is no damage if no tissue heating can be detected; currently this detectible level is 1/1000 °C. Others say no level of RF is safe.

I think the human body can be modelled as a voltage-dependent resistor, with a low of 300Ω (an electric chair pulling 8A at 2400 vac).
There is a breakpoint at 600v, at which point the skin is punctured and so you lose the protective benefit of skin resistance.

 

[Hero999]

I don't see what the RF debate has got to do with this?

Unless the RF causes heating there is no scientific edvidence to indicate that it can cause tissue damage. The only thing that makes RF any more dangerous than infrared radiation is that it's more penetrating and rases the temperature of the internal organs and not just the skin.

To cause cancer the DNA of cells has to become corrupted, there are two main ways of doing this: chemicals can react with the DNA and corrupt it or ionising radiation can knock out electrons in the DNA causing reactions which damage the DNA. RF radiation is too lower energy to cause any chemical reactions, therefore is chemically inert.

The only way RF can damage cells is by heating them, most of the body can withstand fairly large changes in temperature and a large amount of RF energy would need to be absorbed to cause any damage. The only sensiitive areas of the body are the brain an genitals which are more easilly affected by small changes in temperature.

I think the problem is that most people don't understand the effects of RF radiation on the body and they fear the unkonwn.

EDIT:
I think I can see your point you're talking about safety.

Well there is evidence that repeated electric shocks can damage nerve cells but I can't find it on Wikipedia even though I've read it before.