Low voltage electricity (less than 500 volts) can cause only superficial burns or potentially more serious injury, depending on the above variables. Contact with high voltage (more than 500 volts) can cause serious damage.
In industry, 30 volts is generally considered a conservative limit for dangerous voltages. The cautious person should consider any voltage above 30 volts dangerous and should not rely on normal body resistance for protection against electric shock.
The human body has an inherently high resistance to electrical current, which means that without sufficient voltage, a dangerous amount of current cannot pass through the body and cause injury or death. As a rough rule of thumb, more than fifty volts is enough to drive a potentially lethal current through the body.
Effect of voltages below 50 VAC. is generally considered a low risk in terms of electrical safety. An electric shock at 50 V a.c. It is unlikely to be fatal, however it can still be painful and cause an associated accident due to a reaction to the shock. Voltage above 450 VAC is particularly dangerous.
There are even the few old hands who talk about how they commonly test “low voltage” circuits to see if they are live by touching the leads with the back of their hands. After all, 120v isn’t dangerous unless you get blocked as they are quick to point out. And even then, the risk is minimal.
A human tongue has an average of about 7000 ohms. So 5V / 7000 ohms = 0.0007A or 0.7 mA. At these levels you wouldn’t even feel the electricity, so the voltage is harmless to a human.
That’s a good thing for you – currents big enough to feel can be dangerous when they flow through your body, especially if they take a path that involves your heart or brain. Assuming your experiment used a DC power source, the minimum current required for you to feel something is about 5 milliamps (mA).
Even exposure to standard 110 volt electrical circuits can be fatal under certain conditions. Hand-to-hand, hand or head-to-foot, and ear-to-ear electrical pathways are the most dangerous as they can cause severe damage to the heart, lungs, and brain.
Liu survived more than 70,000 volts despite earlier warnings from experts that the human body can tolerate a maximum of between 20,000 and 50,000 volts, which could prove fatal.
Dr. Michael S. Morse, 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 also possible for something to have passed 10,000 volts and be relatively harmless.
This is very serious because electrical damage to the brain can lead to permanent seizure disorders, depression, anxiety, or other personality changes. In addition, electric shock can cause cardiac arrest, heart injury, potentially fatal cardiac arrhythmias, paralysis, or seizures.
Muscle cramps. Difficulty breathing (or no breathing) Numbness/tingling sensations. Blunt force injuries (if the person was thrown backwards from the shock)
A 277 volt shock can flow 27.7 mA of current. While both are dangerous, the ability to let go is reduced at around 15mA. Essentially, you just hold on to the wires until you fall off the ladder or the fuse/breaker blows.
Most low-voltage lamps are 12 volts. So if you don’t run them with a battery (e.g. in your car) there must be a transformer to reduce the mains supply from 230 volts to 12 volts.
A typical lightning bolt is about 300 million volts and about 30,000 amps. In comparison, household electricity is 120 volts and 15 amps.
TASERs have a current of 2 milliamps and it takes at least 1,000 milliamps – 1 amp – to injure muscles, nerves and the heart.
12V does not pose an electric shock hazard, but it IS a burn hazard.
Even without a short circuit, if you make or break an electrical connection that carries a lot of current, current can pass through the point where the connection is made can get very hot very quickly and burn your fingers.
The human body has a higher impedance to DC currents than AC, which means people are much better able to withstand the effects of electric shock from DC exposure than AC exposure.