Can you touch a live wire without being shocked?

Question

I understand many questions about electric shock from live wires and I apologise for adding to that list but after reading many of them I still have my concerns.

From what I have read from some of these previous questions, if there is a path from the live wire to the soil of the ground then current will flow along that path as there is a potential difference. This is the ground connection. It would be rare to acidentally touch the live wire with your finger whilst also standing on soil.

A more believable scenario would be where you are standing on household flooring material such as tiles or carpet. The current would have to flow through the resistant body as well as the flooring material as well as whatever is between the flooring and soil such as wooden beams. Overall could there be sufficient current to deliver a shock considering the extra layers between a person and the ground?

Answer 1

Yes, you can get sufficient current through the floor, the carpet, and your shoes to get a painful or even deadly shock.

I've gotten some painful zaps by accidentally touching a live wire that was supposed to have been turned off, and that I was pretty sure was turned off.

I've been zapped while standing on an insulated ladder that was on a dry, tiled floor over concrete while wearing rubber soled shoes.

If you are thinking of touching a live wire to see if you can do it, don't.

It hurts and if you aren't as well insulated as you think you are it can kill you.

Answer 2

Can you Touch Live Wire Without Shock? ... if you are standing on an insulator

Can you? Yes.

Should you? No.

If you are properly insulated from any grounded conductor, then if you accidentally touch a live wire, little to no current will flow. What little does flow is due to the stray capacitance between your body and earth, in the order of 100 or so pico farads, and any residual resistive leakage.

This is the same situation as birds perching on an overhead high voltage wire. They are not earthed, so little current flows where they contact the wire.

You should not do this because you are relying on the quality of your incidental insulation from ground to keep you safe. One breach in that insulation, one unplanned movement where you touch something else at the same time, may see you grounded and in trouble. With so many accidental ways to get into trouble, touching a live wire deliberately doesn't seem to make a lot of sense.

Answer 3

I echo the above.

Yes, you can. But, you shouldn’t unless you know what you’re doing and have taken the proper precautions.

Here’s an extreme example:

High voltage cable inspection… https://youtu.be/9tzga6qAaBA

Answer 4

In theory, if you're insulated, no current will flow if you touch a live wire.

In practice things aren't so simple. That insulation, be it rubber boots, rubber mat, or some other non-conductive material, forms a dielectric of a capacitor. The terminals on either side of that 'capacitor' are ground, and your body. Note that the air surrounding you is also a dielectric, and so also forms a capacitor to ground.

So what happens when you touch the live wire, if you're 'insulated'? The wire will charge and discharge that insulating 'capacitor' through your body. How much? Depends on the size of the dielectric including both your 'insulation' and the surrounding air, and on the voltage in question. Could be tingle, a painful shock, or a wallop big enough to kill you.

This answer may shed some more light on your question: Professor said no current flows to ground

Because of this dynamic dielectric behavior, working on live high-voltage wires requires some method of shunting that charge/discharge current away from the body. The high-voltage helicopter guy (see link) is wearing a Faraday cage suit that does this: charge/discharge is conducted through the wires in the suit, not his body.

Bottom line: unless you're trained and properly equipped, under no circumstances is it safe to touch a live circuit carrying potentially-lethal voltage.