Person can let go at will, if muscle control not lost. 15 to 20 milliamperes Painful shock. Muscle control to adjacent muscles lost. 20-50 milliamperes Painful. Severe muscular contractions.
Breathing is difficult.
To put these values in perspective, the current necessary to operate a 120-watt light bulb is eight to ten times more current than would kill a person. These common objects are fatal if the current actually breaks through the skin and body resistance. Above ground wires, however, carry enough force to break through the body's resistance immediately upon contact. The force in these wires can be up to 35,000 volts. The current flow at the bodies resistance level and 120 volts is 240ma, over twice that which causes death.