How easy is it to be harmed from house wiring?

Thread Starter

JBmtk

Joined Jun 29, 2009
23
I figure that it is VERY easy. Say, I cut back the insulation from a power cord and then grab the + and - sides of the wires, one in each hand. People have told me that the body has a range of resistance from a few hundred ohms to the Kohms, but lets just say 1K. 120V/1Kohms will still be .12A, well enough for a pretty decent shook. Even worse is that a circuit breaker would typically allow up to 15A, so if I were to hold onto the wires, I would simply cook. Is this correct?
 

bowez

Joined Sep 10, 2009
7
Anything over 60mA is going to kill you almost instantly.

If memory serves 50mA is fatal well over 75% of the time, and 40mA is the most one can "safely" take. Been there done that and was not fun at all ruined my day.
 

arpex

Joined Sep 20, 2009
8
The key point is the path in which the current flows. Your heart does not beat properly if the current flows through it and that kills you. If you touch the wires with one finger and you are not conducting to ground through your shoes say, then it hurts, but will not kill you. If you are bare foot and touch the live wire, then there is a path to ground down your arm, through your chest ( and heart ) down to the ground and you can die.
 

t06afre

Joined May 11, 2009
5,934
Anything over 60mA is going to kill you almost instantly.
If memory serves 50mA is fatal well over 75% of the time, and 40mA is the most one can "safely" take. Been there done that and was not fun at all ruined my day.
No it all depends on the current path. 50 mA going through the hart my stop your hart, or disturb the heart beat pattern. But it may also start a stopped heart. This is used in defibrillators.
A current of up to 60 mA may be used by the anaesthetist to check if you are properly anesthetized before surgery. But the electrodes are placed on your arm so it do not pass through your heart. It is also not a DC current but a square wave say 100Hz .2 mSec high, 9.8 mSec low
 
Last edited:

BillB3857

Joined Feb 28, 2009
2,570
At one time, a long, long time ago, an appliance was sold that had stainless steel bars with points running down either side of a plastic housing. Hotdogs were placed between the points and the lid closed. When plugged into the house wiring, the hotdogs cooked in about 1 minute or less. Due to severe safety concerns, products of that type are no longer marketed.
 

Thread Starter

JBmtk

Joined Jun 29, 2009
23
The key point is the path in which the current flows. Your heart does not beat properly if the current flows through it and that kills you. If you touch the wires with one finger and you are not conducting to ground through your shoes say, then it hurts, but will not kill you. If you are bare foot and touch the live wire, then there is a path to ground down your arm, through your chest ( and heart ) down to the ground and you can die.
Say that I am barefoot and I am standing on carpet or wood. Surely, the resistance to earth would very great and would limit the current to safe levels.....?
 

Audioguru

Joined Dec 20, 2007
11,248
Say that I am barefoot and I am standing on carpet or wood. Surely, the resistance to earth would very great and would limit the current to safe levels.....?
Not if the carpet or wood is wet and a ground is nearby.

You are supposed to turn off the power if you work with an electricity connection. Although I have replaced receptacles with an insulated screwdriver and pliers with the power still on.
 

beenthere

Joined Apr 20, 2004
15,819
We have had one such discussion - http://forum.allaboutcircuits.com/showthread.php?t=21809

It becomes fruitless and rather silly to try to think of every possible situation and whether that one instance is dangerous, or possibly not.

The reasonable approach to house wiring is that any wire must be considered to be carrying a lethal voltage unless it can be verified as safe by means of a meter. There are no absolutely safe circumstances that permit you to come in contact with a live wire.
 
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