Computer Electrocutes Sweaty Student
A college student was so worried about his expenses he refused to turn on his air conditioner, even when he noticed it was hot enough to over heat his computer.
20 year old Wu, a student from Shanghai, decided instead to take off the computer case around his CPU to help cool it off.
His sweaty legs came into contact with the computer’s wiring and electrocuted him. Medical examiners found bruises on his legs and blood in his nostrils confirming death by electrocution.
This photo is really funny. My kitten was in the same position as this recently. I had to extract it carefully
Now, technology really could kill.
The irony of it all is that taking the case off a computer actually makes it run HOTTER.
Which of course would be correct if not for facts.
It will make a computer that already has a good airflow run hotter yes because it compromises the airflow, but if it had good airflow in the first place, it wouldn’t have overheated..
TB.
Good airflow or bad airflow - Any air cooled computer will over heat if the ambient temp is high enough.
Given that the issue was that the ambient temp was overly warm… well you can guess the rest.
This sounds like BS to me. Unless he touched inside the power supply nothing inside the computer has enough voltage to even give you a minor shock.
It’s the current that kills you, not the voltage. There is plenty of current in a sufficiently powered computer to do this. Poor guy.
You have no idea what you’re talking about.
Actually, he is quite correct.
You have no idea what you’re talking about.
Actually the voltage doesn’t matter, only the intensity of the current matters (that thing measured in amps).
Please do some research… Static electricity is usually at voltages in excess of 10,000 volts, but the current is so low, all you get is a minor zap.
However, if you were to get a shock from a 9V supply at a high current level then you would be in serious danger of death.
Actually, it is the power that kills you, and any middle schools kid knows that power is I^2*R or I*V, so it is both the voltage and current that determine your death.
Go read a book pls.
Ugh, You’re all fucking wrong.
Voltage and current are very very related. You need to have enough VOLTAGE to get it to arc through your body. the AMPERAGE is what heats things up and actually hurts you.
This is a bullshit story because:
If Mr Wu had touched both wires to his leg, it would not arc all the way to his head and back to cause the bleeding nose. It would arc to the closes contact to ground, either 1) his leg or 2) the floor, which would cause severe burns to the entry and exit points, but not kill him.
L2Electronics
Are you guys retarded? True, it is the current that kills you, but the body has sufficiently high resistance that it is impossible to pass a high enough current through the human body without a relatively high voltage. You people talk about current like it is independent of voltage, when in reality they are directly linked. One must go up when the other does. Stop spouting out what your 8th grade science teacher told you unless you actually understand what your talking about.
You’re all a bit confused. Current through muscles cause them to contract; enough current permanently damages them. However, voltage causes current to flow. Because PC power supplies deliver only 12V on their highest rail, there’s not enough voltage to cause a dangerous current. Even though there may be 20 amps (or more) flowing across the motherboard with a 3V potential, those 3 volts can’t induce enough current to kill a person.
A 9V battery will not kill you, feel free to lick it. A 12V car battery will not hurt you, even if you happen to be standing in salt water. Below 50V, electronic devices don’t even need to be tested for compliance with safety regulations.
The only way this story could be true is if the guy managed to touch some bare wires from the AC mains, or reached inside the power supply. It doesn’t take much current to kill a person, but it does take a voltage much larger than 12V to cause that current to flow.
Total idiots. Its not the current and voltage, its the combination of the distalic differnce between contact point and the power source. This in some situations can be a deadly combination.
, it’s not the voltage nor the current that kills you, Chuck Norris comes out of nowhere and roundhouse kicks you to oblivion.
Actually, it’s the combination of voltage, current, and resistance that determines the outcome. As simple ohms law states, current equals voltage/resistance. The 12V in a computer could not normally generate enough current to kill someone, because of the bodies natural resistance. However, it all depends on where the current enters the body and other factors (which is why you get shocked when putting a 9V battery to your tongue, but no where else, the tongue has far less resistance to the flow of electrons, just like this guy would have at the time. Because this guy was soaking wet with sweat it is quite plausible that this story could be true as the natural resistance of his body would have been bypassed. Electricity follows the path of least resistance after all.
alright you bunch of know-it-alls!!
RELAX!!
Alright, someone pose this scenario on MythBusters and have them give it a go….
This is BS, voltage on anything coming from the power supply is only 5 to 12 volts. The amps would not be enough to kill him. Not even just the 110 from the outlet would kill him.
its not the volts that kill its the amps .01 amps is enough to kill a human the lowest amped item in computer is 3 amps
The current depends on the voltage. if the voltage is low, then the current will be correspondingly low for a given resistance. I=V/R. Even with sweaty palms, the current generated by a 12V source should not be that high. He may have made contact with the external cables.
Voltage can cause damage to you, but really only at high voltages (tens of thousands)
DC current is less dangerous than AC. AC kills because it screws with the pace off the heart.
His sweaty ass could have just got stuck. Unable to remove himself from contact he may have just cooked like a fine country ham.
“Honey dinner smells delicious. Oh…”
Definitly bullshit story
I agree with Danny. Shenanigans!
Nobodys going to say it? Darwin award winner 2007 nominee.
Seriously… the power from any component can’t kill anything. I bet if i wet my hands and stick the fingers in the sockets i wont die.
go on do it you know you want to. lmao. You do know why they make the hole to small to put your finger in dont you? Its because it can kill you when your fingers are dry, when there wet you’ll almost certainly die, if not death then a really bad 3rd degree burn to your finger, hand and probably a few internals aswell. moron
I’ve shocked myself with a standard 250 watt power supply on several occasions and while it will make you yelp and leave a bit of a tingle, it will not kill you. So unless this guy made contact with a poorly grounded, shorted power cable, its probably bogus
Since voltage in China is 220V it’s definitely possible
Yes, but the power supply converts it and everything else in a computer still sees the same very low DC voltage.
I’m far from an expert but the water reduces the skins resistance to the current (amps) of the computer and I dont know for sure how much amperage it would put through the body but I wouldn’t be surprised if somebody would do the calculations that it would definitely be enough to stop your heart.
Anything greater than 100 mA is enough to kill you. Water does not reduce the resistance, it just makes it easier for the electrons to travel.
And enough voltage can kill you, I = V/R. If the voltage is high enough, the small resistance will soon become disregardable and a large enough current will travel through.
Ha, you’re correct. But I hope you’re joking when you say “Water does not reduce the resistance, it just makes it easier for the electrons to travel.” Electrons travel easier = less resistance.
Yes, but after .2 amps it is enough to re-start your heart.
I fourth this motion. No way could any supply post power supply, kill a grown man. Veto
@Mainomega:
Dare you to try…
Yeah, I double-dog dare you to lick the power leads on the mother board….
Alright, I’m tired of people quoting things they saw on mythbusters or something about “volts don’t kill, amps do” and the like. While this IS true in its base, most people have no idea what it means.
First, to prove it, your car battery can put out up to 1000 amps. One thousand. Your starter motor needs that kind of current. Now go grab the terminals on the battery, notice that nothing happens. Wet your hands in salty water, still nothing. Have an open cut? well, you might feel it then.
Typically you won’t be effected by a voltage under 30-50 volts. This varies with skin thickness, temperature, hydration, and LOTS of other things.
As for the .1 amps can kill you, or .05, or whatever the stat you see that day. This is true if directly applied. Across the heart. And it CAN kill you, not WILL. I’ve been hit by 120 volt here in Canada more times then I can remember. The pain varied depending on how well I was grounded, and where I got hit. I’ve felt 220 in Europe, it hurt a bit more. I’ve gelt 7500 volt, not something i liked. But all these left me alive and well, but some COULD have killed me.
So, like many things in life, nothing is absolute. Lightning leaves some alive, while it is insanely high in both voltage and amperage. Just please, stop saying that low voltages are so scary. Point of interest, a phone line caries enough power when ringing to kill a class full of people, if properly applied. By that i mean i have wires running into the hearts of each person. And even then, a few of those hearts will keep beating, for whatever reason.
This article as currently posted is pure nonsense.
I’ve been shocked many, many times with 120 VAC at 60 Hz (standard USA house current) and occasionally by 240 and 480 VAC and I never got electrocuted, not even when I was covered in sweat and took a painful hit from 220 VAC on a 30 Amp breaker.
And the urban legend about volts .vs. amps doesn’t make any sense since a conductor draws whatever amps it can take (you can’t make a 100W light bulb brighter by putting in a bigger fuse).
Now, the 30,000 volt hi-freq from an old monitor flyback, that nearly killed me… despite my body being a very poor conductor, and consequently accepting very few amps… so I tend to worry more about frequency than either volts or amps. You can touch both terminals of your car battery without feeling a thing, but run the exact same current through your ignition coil and the high-freq will HURT your ass.
I don’t know why you were worried about the 30,000 volts. Nobody ever gets killed by a piddly 30,000 volts. Just not enough amps with that.
Well if you think about it… sweat conatins salt so it’s an electolyte and it only takes 6 miliamps across the heart to kill you. I reckon it’s plausible.
It’s absolutely possible to be killed by a low, DC voltage source. Ten milliamps is enough to kill in a *worst-case* situation. One hundred milliamps or 0.1 A often kills. The higher the amperage, the more likely is death. A higher voltage simply makes a higher, lethal amperage more likely. Using Ohm’s law, a power supply of 5V could drive 10 mA through a resistance of 500 ohms. The resistance of dry skin is typically thousands of ohms, which protects people from electrocution from such low voltage sources. If it weren’t for the resistance of our skin, our salty internal bodies have almost no resistance. An open wound provides a gateway into our nonresistive internal tissue. If only one electrode is touching an open wound while the other touches dry skin, then there would be no problem from low voltage. But if both electrodes touch open wound, trouble can ensue. Recall the pain of a fresh 9V battery when its two electrodes are placed in solid contact with your wet tongue. Sweaty, salt-watery skin has low resistance, too. Furthermore, if the area of electrical contact with the body is a large patch (such as a computer case touching a large portion of a thigh), the resistance will be even lower. (Remember how two resistors in parallel produce a resistance that is lower.)
In conclusion, while the story might be fabricated, elements of the story are consistent with conditions that would be fatal.
“Medical examiners found bruises on his legs and blood in his nostrils confirming death by electrocution.”
Then how do you explain this?
We build hundreds of custom computers. I assure you that except for INSIDE the power supply there is NOTHING in a computer that can electrocute you. If you think otherwise, you have absoluetly no clue about what you’re talking about. Typically everything coming out of the power supply is either 3.3, 5, or 12 volts DC. 12 volts is the ceiling on the voltage.
12V can drive 0.1A through a 12 ohm resistor. If you moistened large patches of your body with salt water, I guarantee the resistance of those patches will be less than 12 ohms. Now put one of those patches on each side of your torso, with your heart lying on the path between. Connect the electrodes, and in just a moment… you’re DEAD.
It is true that it only takes about .2 to .3 amps to kill someone, but that current must be sustained and passing through the heart. If it was his leg that touched the computer, it would most likely travel down his leg to the ground. It would hurt like heck, but wouldn’t kill him.
Now let’s consider he may have been wearing shoes. And let’s consider that the computer case was apparently in full contact with his sweaty legs and with his sweaty hands. The large areas of contact create even lower resistance. The very low resistance allows for very high current, even from such a low voltage source. And the electrical circuit that includes his heart then causes DEATH.
The duration of exposure is also an important factor in lethality. Upon initial completion of the circuit through his body, the kid might well have slumped over the computer and thus maintained the current flow through his body for a very long time.
What? Another urban legend raises its ugly head.
Pure water is a very poor electrical conductor. Look it up. Electrical conductivity of water samples is used to determine purity; the fewer impurities, the lower the conductivity of the sample.
Salt water is an OK conductor, though. Sweat certainly works pretty good, and could conceivably cause an electrical current (which will follow the path of least resistance) to flow around your body and leave you entirely “unshocked”.
Sweat doesn’t cause current. It does reduce resistance of the skin. And a large area of contact between the electrified device (computer) and the skin will reduce the resistance even more. Once the skin barrier is breached, internal tissue of the body has a very low resistance. Create a circuit that includes the heart, add prolonged exposure to the current (such as a guy slumped over the computer after the initial contact), and you soon get a dead guy.
Quit acting like smart @$$3$ & just take it as a message that you should not play with moisture & electricity.
Fox News & Shanghai Daily both have this.
Search “Computer Electrocutes Sweaty Student” on Google & you will find the articles in the top 5 results.
Wow, there are a lot of morons around…
All it takes is a strong enough current to run through the heart in order to kill.
As the current in a computer can be quite high, it is perfectly reasonable to die from this - all he’d need to do is have the arm, on the opposite side to the leg in contact with the computer, touching something better grounded than anywhere else on his body…
You *can* die from low voltage electricity…
You guys are all pushing around the wrong arguments. Does anyone here know what the electrical standards are for housing in the Shanghai’s Yangpu District? The article doesn’t mention it, but even better, what about the electrical standards in a cheap college dorm room since the article mentioned that he was a college student? Standards in China are alot different than the ones in the US. So before anyone else claims fake/urban legend, unless you live in that specific building, you never know what could have happened…
Apparently the only way he could get shocked is if there was a fault in the power supply and if the computer was unearthed. In which case he would be brown bread.
Yes, a current of high enough amperage can kill… *IF* as several people pointed out, it goes through the HEART.
How on bloody earth did it go through his heart if he touched his legs to the wires??
It either went down his leg into the ground, or from one leg to the other (through the crotch which would hurt but is not the heart) if both legs touched it…
To go through his heart he must have also touched his left hand (unmentioned) as well as his legs.
u idiots. voltage doesn’t matter. u can get zap if current is too high with very low voltage. yeh 10000 voltage kills u at low current and vice vasa. pay attention in class. jerks!
Hmmm… my first post didn’t seem to take so I’ll try again.
I used to be an electrician. This story is nonsense. I’ve been shocked many, many times by 120 VAC and it’s no big deal. I don’t even flinch any more for less than 220, and I usually test a wire to see if it’s hot by touching it (as long as I know it’s no more than 120 VAC at 60Hz). I’ve occasionally taken 240 and 480 volt shocks.
In real life, despite the “amps not volts” urban legend, the amps a conductor will take is determined primarily by the conductor as well as the voltage and (most importantly) frequency of the current.
Human bodies, even when sweaty, are very poor conductors. The power supplied to residences are insufficient to overcome the poor conductivity of healthy humans. You can’t get “electrocuted” by a phone in your bathwater, or sticking your tongue in a light socket. You might get a burned-off tongue but you WON’T get electrocuted.
Think about this in your own experience, people! If you take the 15 amp circuit breaker out of your hose and replace it with a 20 amp breaker, do the lights get brighter? NO, a 100 watt bulb will still draw the same current regardless of what current is available from the supply - get it? “It’s the amps not the volts” is bullshit.
Look up what the electric chair uses to kill people - thousands of volts spark-gapped to overcome massive resistance - then realize that it quite frequently does not work, and the victim has to be repeatedly shocked until the liquids within the skull eventually boil, thus killing indirectly. No healthy person’s going to get electrocuted by a computer when it takes well over 15 seconds to kill somebody with a device *designed* for lethal shock!
I once took a 30,000 volt high-frequency hit which threw me into a wall and blanked my brain for a few seconds. That was EXTREMELY painful and left a small mark but did NOT electrocute me.
Right, no one was ever killed by 30,000V. Brain damaged, yes, but not killed.
I really love how, like spike mentioned, people relate everything to what’s in their immediate surroundings. I’ve been overseas and they do use 220volts and since the people can’t afford even our cheapest powersupply here that we take for granted is safe. Its a norm for them to have arcs and blown units over there. That’s also why they use older computer components for reliability. I’m in med school here in the carribean and its funny how students wonder why the laws and benefits aren’t the same on the island as in the states.(BTW, it only takes a small current at the right moment to stop the heart.)
just for the fun of it try it, pour some water on the floor and step on it on bare feet an touch some positive current you feel the shock, salty water or not the water is dangerous with electricity, gives more boost. search physics book!
So that what makes a pc work.
Wow, he gives all nerds a bad name - excessive sweating can be bad, but it shouldn’t ever kill anyone, someone should of sent him some antiperspirant.
I think it has to be fake, I just don’t think there’s enough power inside a computer to electrocute anyone, no matter how much perspiration is on your body.
Wow - sweating kills - I believe it, I’ve been shocked by installing stuff in my PC and I wasn’t even sweating a lot…
Ever heard of the path of least resistance? This applies here regardless of the specifications of the power supply. A faulty power supply can in fact be a hazard to your life in much the same way a simple toaster and a little bit of water can end your life in literally a heartbeat. Don’t be so foolish. Don’t stick your fingers in the socket. Don’t touch or come into indirect contact with any power source.
Actually , If the power supply was an old AT unit, with the push button AC switch it would kill you. If the computer was sitting on the floor on his left hand side and his wet leg brushed againsed the case, I have seen some shitty designed switches which could come in contact with bare skin if the case was off
Just a thought
Well, I think you are all just wanting your five minutes of fame. I have been killed by a very little amount of energy, it took 10 minutes of CPR to bring me back. I dont care what you think, any amount of electricity applied at the right time, to the right place, will end you.
Get off your soap boxes, and do something with your life.
Although unlikely, this IS possible. There could have been a ground fault at the outlet and a HOT AC line touching the computer chassis causing the whole chassis to become live, or just certain chassis parts and/or wiring. Like I said, unlikely but most assuredly possible. People have died from touching their lips to ungrounded microphones and guitars.
You guys need to go take a course in semiconductors and learn about how transformers work, the difference between AC and DC current and Ohms Law.
Anything roughly 50mA (.05I) and above is deadly and even less if your skin is pierced.
Think of Volts as a bus and Amps as the people inside the bus. The bigger the bus, the more passengers and vice versa. Think of small children getting hit by the bus as resistance.
DC generates a continuous, non-sine wave which is constant so you do not feel the typical jolts as you would with AC since AC uses sine waves. Even so, we use 120vRMS but it peaks at 170v to - 170v until it hits a transformer which turns it into DC power. This is what power supplies do and there is enough current stored in it to potentially kill you.
Remember your wire colors too. Red your dead.
Even a small amount of current crossing over your heart can kill you. Disrupt the heart cycle = dead you.
Yeah, a winner! Geez, you’re a rarety in this thread. Congratulations on know the right answer.
wow…so many comments ^_^ i guess that guy wasnt lucky enough to live…
For the several people here who say they work on computers and all the others who seem adamant that they know the principles involved and that low voltage can’t kill, I’m very surprised by the naivety expressed in this thread. A few people do “get it”, but most are just plain out to lunch.
12V won’t kill you, even if the power source can supply a milion amps. current=V/R. Do the math. The resistance of your body is too high for 12 volts to kill you.
Only dry skin has high resistance. The moist, salty tissue of your body has very little resistance at all. Under the “proper” conditions, 12V can indeed kill.
Its bull by the way but here is a little clarification on the amps or voltage argument.
First you need enough voltage to cause the electrons to flow.
Lets now assume that you do. You must also have the correct amperage to kill yourself. You can have too much and it might kill you if your heart doesn’t resume beating correctly but it is likely you’ll survive if the contact time is short.
Amperage too low == No harm.
HERE IS THE IMPORTANT PART>>>>If the amperage is in the right range (I believe its around 1 amp), your heart will tear itself apart from violently beating and you’ll die.
The lesson in short. Too Much Amps = Lockup, Too Little = No Effect, Just Right = Tear It Up. (Remember to have enough voltage to overcome the resistance)
I suffer from hyperhidrosis so it looks like I’m gonna be putting plastic over everything from now on, especially my computer, don’t want to be electrocuted by excessive perspiration, what a horrible way to go.
Poor dude…
It sounds like he had a fight with his girlfriend and
she shoved a bare power supply up his ass, to
electocute him. End of arguments.
It sounds like he had a fight with his girlfriend and
she shoved a bare power supply, up his butt and
he got toasted.
UM…WHAT ABOUT THE HOME CIRCUIT BREAKERS THAT SHOULD HAVE KICKED IN???