Thus, in the absence of high voltage, flowing current cannot flow through the body or cause injury or death. For example, a shock of 20,000 volts is passed through the body but the current is extremely low and duration is short, the shock would be harmless.
A static electricity shock can be 20,000 volts or more, but at extremely low current and for an extremely short duration: Harmless. A 9V battery is at an insufficient voltage to drive a dangerous level of current through the body: Harmless.
A good rule of thumb is that when a shock is at or above 2,700 volts, it often results in death or severe injury. At over 11,000 volts, the victim will usually pass away. A good rule of thumb is that when a shock is at or above 2,700 volts, the person often dies or experiences severe injury.
Dr. Michael S. Morse, a professor of electrical engineering at the University of San Diego, explains that while 10,000 volts can be life threatening in certain circumstances, it's possible for something to have 10,000 volts behind it and be relatively harmless.
The impedance might be in the source (like the resistance in spark plug wires for example), or it can be in the human body, and the human body resistance can vary significantly depending on lots of factors. So, under certain circumstances, you might survive 2,000 volts, or even much more.
Thus, in the absence of high voltage, flowing current cannot flow through the body or cause injury or death. For example, a shock of 20,000 volts is passed through the body but the current is extremely low and duration is short, the shock would be harmless.
Once the skin is punctured, the lowered resistance results in massive current flow. Ohm's law is used to demonstrate the action. At 1,000 volts, Current = Volts/Ohms = 1,000/500 = 2 Amps which can cause cardiac arrest and serious damage to internal organs.
12V isn't a shock hazard, but it IS a burn hazard.
Even without a short circuit, if you make or break an electrical connection that has a lot of current going through it, the point at which the connection is made can get very hot very quickly and can burn your fingers.
"If a healthy person receives a shock of 5,000 volts, they may die on the spot. "In the case of this frozen patient, the task seemed impossible." By comparison in the use of execution by electrocution, a jolt of 2,000 volts is typically used, destroying the brain, followed by shocks with a lessor voltage.
The frequency of the AC has a lot to do with the effect on the human body. Unfortunately, 60 cycles is in the most harmful range. At this frequency, as little as 25 volts can kill. On the other hand, people have withstood 40,000 volts at a frequency of a million cycles/sec or so without fatal effects.
The TASER energy weapons use a peak voltage of 50,000 volts so that the electrons can be propelled across a 2 inch air gap. The high voltage causes electrons to “jump the gap,” a process that “ionizes” the air gap in what appears to the user as a bright arc.
Current Kills, Not the Voltage. But Voltage is must to drive the Current. I.e. Amperes are responsible for electrocution, Not the Volts.
It's The Current That Kills
The real measure of shock's intensity lies in the amount of current (amperes) forced though the body, and not the voltage. Any electrical device used on a house wiring circuit can, under certain conditions, transmit a fatal current.
If the person is not connected to anything that can pass a current to ground, then very little will happen. Its similar to the way a bird can safely sit on a live wire. The person may feel some tingling (due to small capacitive charging and discharging currents through fingers), but no harm will come to the person.
A typical lightning flash is about 300 million Volts and about 30,000 Amps. In comparison, household current is 120 Volts and 15 Amps.
The ignition system on modern cars can have voltage approaching thirty k. Lots of mechanics and tinkerers get shocked working on them, and maybe once in a long while one of them dies from a heart attack, but no, the voltage alone is not enough to kill you.
1 million volts can kill even with a fairly low amperage but if the amperage is low enough 1 million volts will not even hurt.
A combination of voltage AND current kills you. That 400kV is very low current, and the current is so low enough that is unlikely to hurt you because the human skin is usually dry and has high resistance. If you were to break the skin and insert the wires in your blood or something like that, you could kill yourself.
The amount of internal current a person can withstand and still be able to control the muscles of the arm and hand can be less than 10 milliamperes (milliamps or mA). Currents above 10 mA can paralyze or “freeze” muscles.
Remember, it has been suggested a current of only 17 milliamps may induce ventricular (heart) fibrillation. With a hand-to-hand resistance of 1000 Ω, it would only take 17 volts to create this dangerous condition.
An electrical current at 1,000 volts is no more deadly than a current at 100 volts. But tiny changes in a current's amperage can mean the difference between life and death when a person receives an electrical shock.
At a very basic level, this suggests that 12 volt LED systems would have the lowest possibility of causing an electric shock, while 24 volt would be slightly higher but still relatively low, and 120 volt line voltage would be much higher in terms of the possibility of causing an electric shock.
Stun guns, which have been used by law enforcement for decades, can temporarily immobilize a person — think of someone who is combative or resisting arrest, for instance — by jolting them with 50,000 volts of electricity. A discharge, also known as a “cycle,” can last five seconds.
They were divided into four groups, and five second shocks of 50,000 volts were administered to two of them. The researchers found "statistically significant reductions" in verbal learning and memory; some participants also had trouble concentrating, and they felt overwhelmed and anxious.
Each neuron in the brain possesses the ability to accumulate a charge across its cell membrane, which results in a small, but meaningful voltage. The average neuron contains a resting voltage of approximately 70 millivolts or 0.07 volts.