Is it safe to be tased by a Taser?

In summary: Standing on concrete makes the current flow more quickly than if you were on carpet. And of course, if you're holding something (a wood table leg?), the current will be considerably less.
  • #1
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Today I was over at my wife's parent's house. My wife and her mom were doing a puzzle on a work bench. My wife told me she heard a buzzing under the work bench. Her mom has hearing problems and couldn't hear it but I certainly could, it was quite loud. I looked and it was coming from a lamp type wire in a box (guess it was plugged into a powerstrip somewhere). Looked like a wire was split wide open and it was nearly sparking. Long story short her mom didn't know it was live and proceeded to flail it around. It hit my thigh and gave me a shock. I was wearing jeans and thick soled hiking shoes standing on concrete floor. I was crouching and don't think I was holding anything, maybe a wood table leg. The shock wasn't too much, just gave me a scare. Just curious what the factors in this shock and just how much danger was I in?
 
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  • #2
Greg Bernhardt said:
Today I was over at my wife's parent's house. My wife and her mom were doing a puzzle on a work bench. My wife told me she heard a buzzing under the work bench. Her mom has hearing problems and couldn't hear it but I certainly could, it was quite loud. I looked and it was coming from a lamp type wire in a box (guess it was plugged into a powerstrip somewhere). Looked like a wire was split wide open and it was nearly sparking. Long story short her mom didn't know it was live and proceeded to flail it around. It hit my thigh and gave me a shock. I was wearing jeans and thick soled hiking shoes standing on concrete floor. I was crouching and don't think I was holding anything, maybe a wood table leg. The shock wasn't too much, just gave me a scare. Just curious what the factors in this shock and just how much danger was I in?
We have here (Europe) the doubled value of voltage (220V) and unless you're suffering from severe heart problems or are another way of a weak constitution nothing will happen. Ok, you shouldn't do it taking a bath. I got my first shock as a kid when I tried to crack an old gaming machine my father got from somewhere to get the coins back. (There is also a famous song here which I call the electrician hymn: "Touched a 1000 times, a 1000 times has nothing happened, and then it has made boom!)
 
  • #3
If enough current flows through your body it will kill you. I think anything over about 30mA has the potential to be fatal. The voltage needed to produce that current depends on the resistance of your body and the resistance between your skin and the source. So if you are well hydrated and sweaty then the voltage required will be lower. The path through you body also makes a difference. Thigh down leg to ground is going to be less dangerous than from one hand to the other via your heart. As I recall it's generally accepted that anything over about 42V has the potential to be fatal but it's unlikely at such a low voltage.

What country are you in? I'm in the UK where the mains is 230V AC. That's more dangerous than the 110V used in the USA but I've survived at least three mains shocks - perhaps because I follow the rule... If you really must work on live equipment best wear rubber soled shoes and keep one hand in your pocket. It doesn't guarantee you will survive a shock ut every little helps.
 
  • #4
Greg Bernhardt said:
Long story short her mom didn't know it was live and proceeded to flail it around. It hit my thigh and gave me a shock.
Um hmmm...or maybe she has skills you weren't aware of and used them successfully and with plausible deniability? Clever, that one.
I was wearing jeans and thick soled hiking shoes standing on concrete floor. I was crouching and don't think I was holding anything, maybe a wood table leg. The shock wasn't too much, just gave me a scare. Just curious what the factors in this shock and just how much danger was I in?
Probably not much. Generally, power cord shocks involve touching both leads, which makes the electricity flow only a short distance, but even if you only touched one, the current would have a long way to go and through most of the mass of your body to get to your heart. It isn't a likely scenario for an electrocution.
 
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  • #5
I knew a technician who used to check 220V appliances with his fingers. (I think he was crazy; don't do this.)

The big problems are compromised skin resistance (wet, stuck with a needle, etc.) and current across the heart. You had neither and were safe-ish. However that was just lucky. Had you just spilled a drink or such it could have killed you. Rule of thumb: Don't mess with live wires.

Not of concern here: Really high currents (think lightning) can also cause internal burns which often can't be felt. These can cause necrosis or organ damage killing days after the accident.
 
  • #6
Let me add a treatment suggestion: CPR. Hearts stopped by electric shocks can often be restarted by CPR. CPR doesn't usually help heart attacks (because it doesn't fix whatever was wrong in the first place), but works much better when the heart is otherwise healthy like after an electric shock.
 
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  • #7
I'd say from my own experience that mains ac shocks are mostly dangerous if they happen to either stop the heart or cause ventricular fibrillation.
Here in Europe we do have 230v and even this level of AC voltage doesn't hurt the body much if only for the heart , the heart surely is the weakest link when it comes to electricity.
when I was a kid i touched a live 230v phase wire and the electricity ran through my arm down my body through my legs into the concrete pavement , since it passed the heart around the only thing that happened was that I couldn't feel my legs for some 2 minutes so I had to pull myself along using my arms.
Also from other shocks I have mostly just felt very fast and a bit irregular heartbeat, apart from that I doubt that short term exposure to ac mains can cause any other major health problems except for the dangers of messing up the heart which is why I think it's still dangerous because sometimes for example when you get fibrillation even doctors can't stop it and if they can't do that in quite a short amount of time , well you basically die.
So as the old safety books say , one should avoid the ac to pass from one arm to the other because that almoust definitely will go through the heart and as I said going through the heart is the concern. also one should avoid a diagonal current flow from left arm to right leg and right arm to left leg because that path also has a high chance of taking the heart in it's way.
when i touched the live phase and neutral with my two fingers the current was almoust entirely going just throgh my fingers and not much into the body since i was standing on a isolated floor and so there wasn't much danger in that except for some tickling after effects felt into the fingers.
not that I'm saying one should do that.

I think DC has a higher potential to cause other than heart problems , like burning skin or internal organs due to the nature of DC current.
 
  • #8
I'm surprised the wire wasn't smoking and spitting sparks.

Your shoes insulated you from the concrete floor , and the concrete is only a mediocre conductor.

One can feel a current of 0.0001 amp and 0.001 will be sensed as a substantial shock.
and around 0.01 amp it grabs your muscles hard enough you can't let go
http://ecmweb.com/content/basics-electric-shock

Jeff's technician friend presumably used the "Old Electrician's Digital VoltMeter" technique -
OEDVM: Touch it with the BACK of your fingers so when your muscles contract from the shock it pulls your finger AWAY from the wire instead of grabbing it harder.
That's how they live to be old electricians...

I once quite accidentally got across an outboard motor spark plug - went in my left hand and out my right. I counted seven zaps as the engine rolled to a stop.
Didn't bother my brand new Guidant pacemaker at all - more robust than they'd have you think .
 
  • #9
jim hardy said:
Touch it with the BACK of your fingers
It always amazes me that people don't seem to know about this dodge. It can save a lot of discomfort and won't leave you quivering like an idiot.
 
  • #10
Caution required: You should not be out with your wife and especially not at her parents house. You may have actually been assaulted by her mom; I am familiar with such. What were you thinking? When I venture out with my wife, I insist she count it as a 'date'...so I get some credit!

Some descriptions of what can go wrong here: https://en.wikipedia.org/wiki/Electric_shock

"A sustained electric shock from AC at 120 V, 60 Hz is an especially dangerous source of ventricular fibrillation because it usually exceeds the let-go threshold, while not delivering enough initial energy to propel the person away from the source.

jim hardy said:
Touch it with the BACK of your fingers so when your muscles contract from the shock it pulls your finger AWAY from the wire instead of grabbing it harder.

Clever. I prefer to use use a voltmeter.

I once quite accidentally got across an outboard motor spark plug - went in my left hand and out my right.

That's roughly 20,000 volts or so on older breaker point type ignition systems. Automobiles, lawnmowers, snowblowers, all similar. If solid state ignition,common on all those nowadays, on the order of almost double the voltage. Stick with diesel engines if you are prone to grabbing uninsulated wires.

USA ground fault circuit interrupters [GFCI] trip at about 5 ma, European about 30 ma. They protect but do not guarantee safety in all circumstances. Deaths in salt or fresh water around boats in marinas have caused a lot of investigations. Turns out smaller than expected leakage currents can be fatal to swimmers.

This I did not know: [USA] UL has issued major revisions to UL 943, the standard for safety for GFCI that take effect on June 29, 2015.
https://www.legrand.us/passandseymour/gfci-receptacles/self-test-gfci/ul-943-gfci-standard.aspx#.Vsm4XX1OmXY

Greg Bernhardt said:
just how much danger was I in?

Enough to avoid such situations when possible. I wonder how many people are electrocuted or seriously injured annually from, say 120 volts in dry household conditions.

http://www.esfi.org/resource/holiday-data-and-statistics-359
  • Each year, there is an estimated average of 60 electrocutions associated with consumer products. The three most common product categories associated with electrocutions are small appliance, power tool, and lighting equipment.
  • Every year in the U.S., more than 2,600 people are killed in home fires.

http://www.ecmag.com/section/safety/alarming-statistics [Likely construction, high voltage]

“To the best of my knowledge, there are more than 30,000 nonfatal electrical shock accidents that occur each year, with a lot of incidents going unreported,” ... It is believed that for every 300,000 at-risk behaviors, there are about 300 recordable injuries, 30 lost-time injuries and one fatality.
 
  • #11
alw34 said:
Stick with diesel engines if you are prone to grabbing uninsulated wires.
Better stick with no engines at all in that case.
Greg Bernhardt said:
Today I was over at my wife's parent's house. My wife and her mom were doing a puzzle on a work bench. My wife told me she heard a buzzing under the work bench. Her mom has hearing problems and couldn't hear it but I certainly could, it was quite loud. I looked and it was coming from a lamp type wire in a box (guess it was plugged into a powerstrip somewhere). Looked like a wire was split wide open and it was nearly sparking. Long story short her mom didn't know it was live and proceeded to flail it around.
Why would you get close to a power cord that makes some noise?

If the heart could be part of the current flow, it is a medical emergency for a day - even if there are no notable effects immediately, the heart can get problems later. The other parts should be fine if the shock was from 110 V, short in time and without notable effects.
jim hardy said:
Jeff's technician friend presumably used the "Old Electrician's Digital VoltMeter" technique -
OEDVM: Touch it with the BACK of your fingers so when your muscles contract from the shock it pulls your finger AWAY from the wire instead of grabbing it harder.
That's how they live to be old electricians...
Sounds quite analog to me ;).
 
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  • #12
mfb said:
Why would you get close to a power cord that makes some noise?
It was under the bench and I didn't know what it was. I wasn't that close, just peeking under the bench. My mother in law then whipped the cord out. :rolleyes::mad:
 
  • #13
jim hardy said:
Your shoes insulated you from the concrete floor , and the concrete is only a mediocre conductor.
A dry concrete floor can have more than enough conductivity if you are bare foot, or even if your shoes are wet or moist.
alw34 said:
"A sustained electric shock from AC at 120 V, 60 Hz is an especially dangerous source of ventricular fibrillation because it usually exceeds the let-go threshold, while not delivering enough initial energy to propel the person away from the source.
I was standing bare foot on a dry concrete floor when I reached to pulled the metal chain switch on a desk lamp. Due to a defect in the lamp the chain was shorted to the 120v hot wire. I remember seeing my hand contacting the chain, but I could not move away from it. My muscles were frozen. The next thing I remember I was laying on the floor very disoriented. The current felt like a vibration of millions of little needles puncturing my body (from the inside) from my right arm down to the concrete floor. Also, although I don't remember it, I must have yelled out or made some kind of noise because my mother came to the door and asked if I was ok. It was the worst electric shock I've ever received.
 
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  • #14
Greg Bernhardt said:
My mother in law then whipped the cord out.

TurtleMeister said:
my mother came to the door and asked if I was ok.

There you go!
Proof that mothers and mothers in law are quite different!
 
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  • #15
Now there's first hand experience. Your fingers locked onto that chain by the shock?

Thanks !
alw34 said:
If solid state ignition,common on all those nowadays, on the order of almost double the voltage. Stick with diesel engines if you are prone to grabbing uninsulated wires.

That outboard was capacitive discharge electronic ignition. The spark is noticeably more intense than a lawnmower or 1950's outboard magneto.

alw34 said:
his I did not know: [USA] UL has issued major revisions to UL 943, the standard for safety for GFCI that take effect on June 29, 2015.
https://www.legrand.us/passandseymour/gfci-receptacles/self-test-gfci/ul-943-gfci-standard.aspx#.Vsm4XX1OmXY
Oh my, the price will double again.
I like the reversed wiring feature but not the automatic self test. I'm part Luddite.
 
  • #16
apart from the jokes about mother's in law which are funny as always MFB is actually very correct the thing most people don't know or don't remember that for some people problems with the heart after an shock can start showing themselves after some hours.
 
  • #17
Greg Bernhardt said:
The shock wasn't too much, just gave me a scare.
Let this be a lesson; 115 vac is too often taken for granted as not dangerous.
TurtleMeister said:
Due to a defect in the lamp the chain was shorted to the 120v hot wire.
The "old timers" realized this possible problem. :approve:
chain.jpg
 
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  • #18
How are tazers considered safe? The videos look nasty where people get tazed. My shock was nothing like that.
 
  • #19
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  • #20
jim hardy said:
Now there's first hand experience. Your fingers locked onto that chain by the shock?
My fingers, and my whole body, were just frozen in place. I was saved by gravity.
dlgoff said:
The "old timers" realized this possible problem. :approve:
View attachment 96262
Very nice solution. I've never seen that before.
 
  • #21
Hi Greg,

The shock wasn't too much said:
The short answer to your question is about a week long course in electrical safety.
The longer answer is that is is unlikely one could recreate the exact conditions that existed at that time.
The range of outcomes that could have happened are nothing at all to death. Having said that...
  • Each year, there is an estimated average of 60 electrocutions associated with consumer products. The three most common product categories associated with electrocutions are small appliance, power tool, and lighting equipment.
These are electrocutions that happen at home. There are many more that are job related.

The factors in general are simple. Voltage, and in this case AC. Current in amps or milli amps in your case. Resistance in ohms. The resistance part is not so simple because to many unknowable factors existed. Condition of the cloth, condition of your skin and many many other factors.

Here is a silly little video I made kinda showing some of the stuff I go through trying to not kill myself messin around with electric stuff...lol
 
  • #22
a taser gives you a bigger shock because there is high voltage used but very small current capacity , the high voltage simply has the effect to paralyze the nerves and cause muscle cramps and make one unable to move , the lower voltage AC ,even 230VAC in most cases don;t cause such long lasting cramps and effects , for all my personal shocks from mains AC i was always able to pull the hand off myself , and the tickling after effects also were minimal , but the current is what is the concern here and also it's path in the body and if it has taken much of its path through the heart then also its frequency is the dangerous thing.

I'm not speaking from an expert's viewpoint on tasers nor have i ever been attacked by one but i still assume it's more likely to have ventricular fibrillation and or cardiac arrest from a mains AC shock than from a taser.especially when tasers are mostly used in outdoors , and i think if one were to grab a live 230VAC phase while standing on moist ground he would definitely be dead or atleast have severe problems afterwards.
also when speaking about low current high voltage many older electricians who used to repair CRT's have gotten one from the HV tube drive voltage not so much lethal but very painful it was, they say.
 
  • #23
I never got an electrical shock. Worked with up to 1 kV, but always insulated - if you want to measure below nanoamperes you have no other choice anyway.

Something I always wondered: Where does the voltage-dependent resistance come from? You frequently see resistance values of the order of a kOhm, but that is certainly not true if you have low voltages. At 1-5 V, the current flow is in the low microampere range, even with wet fingers the resistance is much more than 1 kOhm. What happens at higher voltages that reduces the electrical resistance of the skin so massively?
 
  • #24
that is actually a very good question would love to hear the answer myself.
I think it has something to do with why the similar things happen to dielectrics and insulators that with increased voltage their insulating properties and resistance decreases.just that with human skin this decrease happens rather linearly than at some given threshold.
 
  • #25
Greg Bernhardt said:
How are tazers considered safe? The videos look nasty where people get tazed. My shock was nothing like that.
Tasers are tuned in both frequency and waveform to interfere with voluntary muscle nerves. Their frequency is too high to affect the heart directly and their energy is too low to cause life threatening burns.

Tasers are not considered safe. They are less than lethal. Thus they are safer than bullets and make a good substitute for bullets. Poor training and poor media portrayals make them seem safe, but they should only be used in situations where lives are otherwise threatened.

Tasers seem to cause nerve problems which affect the body's homeostasis. This can kill otherwise at risk people (sick, pregnant, etc.) up to several hours after being tasered. Since most police officers are healthy, they often don't consider the possibility some people might be killed by the Taser.

Still, I would rather be shot by a Taser than by a bullet.
 

What are the most common symptoms of an electrical shock?

The most common symptoms of an electrical shock include burns, numbness or tingling sensation, muscle pain or contractions, difficulty breathing, and loss of consciousness.

What should I do if I experience an electrical shock?

If you experience an electrical shock, the first thing to do is to turn off the power source. If you are unable to do so, try to use a non-conductive object to remove the source of electricity from the person. Call for medical help immediately.

Can an electrical shock cause long-term effects?

Yes, an electrical shock can cause long-term effects such as nerve damage, heart problems, and brain damage. It is important to seek medical attention even if the shock seems minor.

How can I prevent electrical shocks?

To prevent electrical shocks, make sure to handle electrical equipment with dry hands and avoid using damaged or frayed cords. It is also important to regularly check and maintain electrical outlets and appliances.

What should I do if someone else experiences an electrical shock?

If someone else experiences an electrical shock, do not touch them until the power source is turned off. Call for medical help immediately and provide first aid if necessary.

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