Tesla Coil Shocks: Health Effects & Risk

[you878]

A friend of mine grabbed a handheld 10,000 volt tesla coil (the metal end) in one hand and a florescent bulb-tube thing in the other, and showed me that he could light the florescent tube using the electricity from the tesla coil. My question is, why did it not shock him, and are there any health effects to doing what he did?

 

[wackyvorlon]

It's because the electricity is at a relatively high frequency it produces a skin effect. The electricity does not actually go through his body, it remains on the surface.

 

[Drakkith]

Could this also have something to do with the amount of current running through or over him as well? Or is it simply a skin effect?

 

[C.Cochran]

Normally a 10,000 volt (DC or low frequency AC) power source would kill you, anything more than .01 amps. The normal body resistance of a human being is 50,000 ohms. So 10,000 divided by 50,000 is .2 A. So, I am guessing that high frequency AC will create a skin effect so that the current doesn't pass through the heart.

 

[Drakkith]

Is it that simple to calculate? I thought that the tesla coil put out a set amount of current and such. So if it put out 0.01 amps or something, how could you get 0.2 amps of current through you? I'm not that familiar with electrical problems unfortunently.

 

[C.Cochran]

Ohms Law says V(Voltage)/R(Resistance) = I (Curent).

"The minimum current a human can feel depends on the current type (AC or DC) and frequency. A person can feel at least 1 mA (.001A)(rms) of AC at 60 Hz, while at least 5 mA for DC. The current may, if it is high enough, cause tissue damage or fibrillation which leads to cardiac arrest. 60 mA (.06A) of AC (rms, 60 Hz) or 300–500 mA (.3 A - .5 A) of DC can cause fibrillation. A sustained electric shock from AC at 120 V, 60 Hz is an especially dangerous source of ventricular fibrillation because it usually exceeds the let-go threshold, while not delivering enough initial energy to propel the person away from the source. However, the potential seriousness of the shock depends on paths through the body that the currents take. Death caused by an electric shock is called electrocution."

I'm not very knowledgeable on electric shock specifically, obviously it depends on a few factors like moisture, current type, frequency, and contact areas. The worst thing you could do is use both hands, seeing as how current flows through the path of least resistance which means right over your chest. The .01A could have been the minimum AC current for that chance of fibrillation, sorry for the confusion.