Volt is not what it takes to kill a man. You could literally shoot up a person with 20,000 V for a short duration of time and nothing would happen to them. It is the current that is capable of killing a man. 20 mA is a lethal current.
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Volts do not kill a man. What would kill the man would be the currents or joules and it would take about 200 to 220 joules to kill a person.