Effects of Electric Current on the Human Body

Dear Mr. Electrician:  What happens to the human body when it comes in contact with electricity.

Answer:  Below is a chart that was compiled many years ago.  It explains what happens to the human body when receiving electrical shocks of different intensities.  Do not try this yourself or on other people.

of Electrical Current
Reaction to
the Human Body
Below 1 milliampere Generally not perceptible
1 milliampere Faint tingle
5 milliamperes Slight shock felt; not painful but disturbing. Average individual can let go. Strong involuntary reactions can lead to other injuries
6–25 milliamperes (women) Painful shock, loss of muscular control*
9–30 milliamperes (men) The freezing current or “let-go” range.*

Individual cannot let go, but can be thrown away from the circuit if extensor muscles are stimulated.
50–150 milliamperes Extreme pain, respiratory arrest, severe muscular contractions. Death is possible.
1,000–4,300 milliamperes Rhythmic pumping action of the heart ceases. Muscular contraction and nerve damage occur; death likely
10,000 milliamperes Cardiac arrest, severe burns; death probable

If the extensor muscles are excited by the shock, the person may be thrown away from the power source.
NOTE: 1000 milliamperes equals one ampere which is approximately the amount of current that flows through a 120 watt light bulb at 120 volts.  
Source: W.B. Kouwenhoven, “Human Safety and Electric Shock,” Electrical Safety Practices, Monograph, 112, Instrument Society of America, p. 93. November 1968.


GFCI receptacles and circuit breakers are designed to shut off power if there is a current imbalance of more than 5 milliamperes.  They are designed to save lives.

When working on electrical wiring, it is important to shut the power off.

Some other safety tips can be read here.