# Who is responsible for Electrical shocks, high current or high voltage? [duplicate]

An electrical shock may cause burns, or it may leave no visible mark on the skin. In either case, an electrical current or voltage passing through the body can cause internal damage, cardiac arrest or other injury. Under certain circumstances, even a small amount of electricity can be fatal.

With that being said, what do you think is responsible for electical shoks, high voltage or hight current, or both at the same time?

## marked as duplicate by W5VO♦May 13 '15 at 15:16

• It is always the current, the rest follows from ohms law. – PlasmaHH May 13 '15 at 15:02

The risk of shock depend on several points ...

To start a voltage (in volts) becomes dangerous to humans from 50V in a dry environment, 25V for a wet environment.

Regarding the electric current in Amperes risks are higher:

1 A Heart Failure

50/75 mA threshold irreversible cardiac fibrillation

30 mA respiratory paralysis threshold beyond 500 ms

10 mA threshold not release, muscle contraction

0.5 mA Threshold very low sensation

So having a low voltage does not mean you're safe because you have to know the current through the human body in case of impact.

• IMO this does not answer the question. – Wouter van Ooijen May 13 '15 at 15:23
• "So having a low voltage does not mean you're safe because you have to know the current through the human body in case of impact." This isn't entirely true. The body has resistance and from ohms law (I=V/R), you need a high enough voltage to produce the high enough value of current to kill you. 12Volts for example, whether you are wet or dry is never going to produce enough current through the human body to kill. The whole thing comes down to body resistance and voltage. It also depends on if what the source of the current is, is that able to produce a high enough current – Dean May 14 '15 at 18:20
• RCD devices to protect against electrical shock from 120V/230V mains AC supply, these typically are set to trigger at 30mA or thereabouts trip current. If a leakage current (through you) is detected at around 30mA then the mains power is cut to prevent electrocution from occurring. – Dean May 14 '15 at 18:25