Electric shock
"Electrocute" redirects here. For the
band, see Electrocute (band).
An electric shock can occur upon contact
of a human body with any source of voltage
high enough to cause sufficient current
through the muscles or hair. The minimum
current a human can feel is thought to be
about 1 milliampere (mA). The current may
cause tissue damage or fibrillation if it is suf-
ficiently high. Death caused by an electric
shock is referred to as electrocution. Gener-
ally, currents approaching 100 mA are lethal
if they pass through sensitive portions of the
body. [1]
Shock effects
Psychological
The perception of electric shock can be dif-
ferent depending on the voltage, duration,
current, path taken, frequency, etc. Current
entering the hand has a threshold of percep-
tion of about 5 to 10 mA (milliampere) for DC
and about 1 to 10 mA for AC at 60 Hz. Shock
perception declines with
increasing fre-
quency, ultimately disappearing at frequen-
cies above 15-20 kHz.
Burns
Heating due to resistance can cause extens-
ive and deep burns. Voltage levels of 500 to
1000 volts tend to cause internal burns due
to the large energy (which is proportional to
the duration multiplied by the square of the
current) available from the source. Damage
due to current is through tissue heating. In
some cases 16 volts might be fatal to a hu-
man being when the electricity passes
through organs such as the heart.
Ventricular fibrillation
A low-voltage (110 or 230 V), 50 or 60-Hz AC
current through the chest for a fraction of a
second may induce ventricular fibrillation at
currents as low as 60 mA. With DC, 300 to
500 mA is required. If the current has a
direct pathway to the heart (e.g., via a cardi-
ac catheter or other kind of electrode), a
much lower current of less than 1 mA, (AC or
DC) can cause fibrillation. If not immediately
treated by defibrillation, fibrillations are usu-
ally lethal because all the heart muscle cells
move independently. Above 200 mA, muscle
contractions are so strong that the heart
muscles cannot move at all.
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