Voltage vs. Current through human body

Discussion in 'General Electronics Chat' started by LED Man, Sep 16, 2008.

1. LED Man Thread Starter Active Member

Jan 15, 2008
62
0
Hey,

If your body is a at a constant resistance (say 2kohm), I figure that as the voltage of the train track (for example) goes up, say from 10v to 500v, that the current gets higher and higher with voltage and that is what kills you.

Is this always the case? Where current flow through your body is proportional to increasing voltage of whatever you touch and complete a circuit with. I thought I heard my professor say today that you could still get shocked with a high voltage but that it would be less dangerous than if you had a lower voltage at a higher current, how would this be possible. Thanks.

2. niftydog AAC Fanatic!

Jun 13, 2007
95
0
Current flow is the thing that does the damage. Current is quite literally a quantity of electrons flowing through a circuit - it is on some level a tangible physical quantity.

Whereas voltage is not a physical entity, it's just a way of describing the conditions that exist in a circuit.

Some high voltage circuits can only source very small currents - so while the voltage is high and can more easily overcome the resistance of your body, the resulting current flow is relatively small.

However, it only takes in the region of 10mA to be potentially lethal.

3. SgtWookie Expert

Jul 17, 2007
22,201
1,809
I'm not an MD, and have absolutely no qualifications to be talking about what current level is lethal and what is not.

I'm also not an EE, and can't give you the precise specifications for trip levels of GFCI breakers.

However, I believe that the trip level of GFCI breakers is set to between 10mA-15mA current.

Pure speculation on my part, but it may be that DC current can be survivably sustained more than AC current because it's less distruptive to the human nervous system.