Avoiding electrocution (Featuring real shocks.)

The majority of electric shocks are painful and surprising, but not fatal. It takes a good electrical contact between two parts of your body between a live source and a return path to allow high current to flow through your body. By understanding electricity and how it flows in differing quantities through many paths of resistance you can avoid putting yourself at risk of a fatal shock.
The safety industry implies that all electrical equipment should be locked out and tagged out before working on it, but in reality that is not always possible, although definitely a better option in the case of easily identified faults.
Much of the current wall of "one size fits all" safety legislation has come about due to the rise of all-trade building and facilities maintenance companies and their use of unskilled labour for economy. They often do minimalist in-house training before making their new "experts" sign liability waivers to avoid any legal repercussions.

Electrocution is normally a result of high current flow through your body. The most common mode of death is fibrillation of the heart. Your heart is actually composed of a large group of muscles that all contract in sync to deliver blood around your body. If they are knocked out of sync by the flow of current causing involuntary contraction of a portion of the heart, then they may not be able to re-sync and the heart will then function incorrectly and fail to deliver blood around the body, resulting in the potential for death.

The best way to defibrillate the heart is to use an AED Automatic External Defibrillator. These have evolved from the big scary hospital machines to sophisticated, affordable and compact units that can openly be bought for home use online and used by people with no previous training in their use due to the full automation and spoken instructions.
A defibrillator is applied across the victims heart by the use of two external electrodes. It then uses very advanced digital signal processing to make one of three decisions. It will NOT attempt to shock a healthy heart or one that is showing no residual activity (flat-lining). If it detects a heart rhythm indicative of a heart in a fibrillated state then it will advise a shock, charge it's capacitor, tell people to stand clear and then authorise the user to press the button. The resultant pulse of high current causes the heart to contract into a known and synchronised state, whereupon externally applied compressions (CPR) can then be used to help establish synchronised beating again as the machine continues to monitor the situation and make further attempts if needed.

It's somewhat ironic that the defibrillator was first developed to try and curb the high fatality rate of linemen in the American power distribution industry. And that now they have evolved to the point they can affordably be put into their trucks as part of their medical kits, the majority still don't have them. This situation is made even more incredulous by the high fatality rate that is ongoing in that particular industry due to their routine work in the vicinity of live power lines. (Isn't this what their union is supposed to deal with?)

[tobortine]

That was one of the most intense videos I've ever seen on You Tube. Even with the certain knowledge that you'd survived, I was feeling anxious as you turned up the current.

[uzaiyaro]

There was a rich businessman here in Australia called Kerry Packer. He had a heart attack and the only reason he survived was because the ambulance that responded to him, happened to have a defibrillator onboard, as not many ambulances did at the time. After this, he paid to have every ambulance in his state fitted with them. They're now also called a "packer whacker"

[paulamos]

I only found your channel by pure chance! I find it incredibly informative, my father did electrical engineering in 1938 then was a WO/AG in RAF at the start of WWII got medical discharge for nerve damage to one hand in' 41, went on to be involved in the building of the Black network of radio transmitters around Woburn Estate. He had a colleague who went to switch over the broadcasting transmitter at the end of his shift, the old man said don't forget the earth deadman's handle, when there was a bang and a rather charred deadman. I don't recall what the current was but the voltage was massive 1000's of volts.
I also remember him in his his late 70's still repairing the old cathode-ray tube televisions with the live chassis, one day I went into his workshop and he was looking in the back of the TV checking various valves (all live), he said "I don't know what the issue is" and "I said what that whistle?", he said "what whistle?" I pointed to a part of the TV and said "high pitch, coming for around about there." He stood up quickly with an exclamation of "Oh bugger!" Rubbing his Wrist. On asking what the problem was, I was told oh, nothing just brushed the chassis! So where's that whistle (he had bad tinnitus by then) and went merrily on.
Another occasion I said, I'm getting a tingle of the kettle and the tap, he came over and looked, put his hand on it and told me I was imaging it, neither my bother or mam could feel it either. I said that I wasn't and I'd get his multimeter and show him. He told me to go and get it then and when tested there was a very small current of 240v A/C showing, it turned out to be an earth leakage from the supplier's side and had to call them out to sort it out. I have over the years toucher 240v A/C and always had a good belt from it, whereas the old man would test a wire by touching it and turning around to say you better take the fuse out, don't want to upset your mother. He died in 2019 aged 99 ½ years old!!

[BrokenVideoProductions]

This was probably the most intense and educational video I've seen.
It would save lives If students was shown this in class. (in sharp contrast to the
spectacular demonstration "how to heat hot-dogs by applying live mains to each end of them",
like my teacher did)

[RichardT]

Am I the only one who was cringing at watching this? Half a bloody world away and I felt your pain! :)

[AsymptoteInverse]

With all your talk of sensible electric safety, I keep thinking of the warehouse where I used to work. We had a big 1, 000-liter mixing tank for liquid fertilizer. Water-based, of course. The water was probably fairly conductive. The salts in the fertilizer were certainly more so. Not long after I started working there, I noticed that, when I touched the fertilizer to check consistency (it was organic, so no worries there), I felt a peculiar nasty tingling in my fingers. I thought it was just my imagination. Then I realized that the mixing-tank was being agitated by a shitty mains-voltage immersion pump, connected to an *unfathomably* shitty power strip which was just cable-tied to the tank and was regularly splashed and soaked with conductive fertilizer. I all but forced my boss to let me drive to the hardware store and get a proper outdoor-rated power strip.

It couldn't have been that much current, since I wasn't connected to ground (and since it didn't kill all three of us who were working with it), but even so, it's a *nasty* sensation. I take my hat off to you for enduring that tingly torture for educational purposes.

[michaelhawthorne]

Boy, that's dedication to bringing safety to the masses.
Way to go Clive.
I remember my first electrical shock at the age of 6 when I put my thumb up into an empty light socket, reaching it by climbing onto a bed then onto a window sill. Luckily I fell forward rather than backwards maybe through the bedroom window.
The scar staid with me for years.

[WafflesASAP]

My man, as soon as you said "let's go again and see if I can get any further, " I had to fast forward. Watching you turn that knob up initially was just sweat-inducing -- I was watching the voltage go down as the current was spread across a larger area, but then I look to the left and I see you're at almost 6 milliamps as the voltage was starting to rise and all I could think of was that you were about to struggle to let the thing go and do actual damage to the muscles in your peripheries. Or worse.

Super scary. I appreciate _why_ you did this, and I honestly believe you've done some good for folks who are watching this and are unaware of exactly how little current it takes to cause major issues internally, but please, _please_ don't ever do anything like this again. You're a brilliant person, and I really enjoy watching your videos because it's rare that I don't _learn something_ while I'm laughing or smirking at how cleverly enjoyable they are. It'd be a major shame if we lost the guy we've all become fond of watching simply because he gave a shit about his viewers, and wanted to show them (for their sake) just how dangerous electricity can be. Even under controlled, educated circumstances, a calculated risk is still a risk.

My best to you and yours, Clive.

--Mitch, from Philadelphia, Pennsylvania

[andysimpson]

Watching this makes me appreciate how luck I am. I was working on an industrial glass washer with a colleague when an 'isolated' faulty drain pump circuit went live. From the index finger on my right arm to my left elbow got full 230V as the pump was running. I was in between two machines so I couldn't fall away. I was live for around 45s. I was conscious throughout. I even remember thinking that I was dead. Couldn't move, couldn't breath. Somehow I managed to fall away but I had real muscle damage across my shoulders and back and my finger was smoking like the end of a cigarette. Easily my most unpleasant experience yet. I'm a very lucky boy indeed, though. I can't understand how I wasn't killed.

[jaythatguyyouknow]

Damnit man. I never even thought about the danger of holding the door while checking a flipped breaker. So glad I binge watch your old videos. You may have prevented my accidental demise

[nailz]

Why do drugs, when you can do electricity?

[RECKLESSFAMILY]

One Victorian (?) engineer said "Facts not Opinions" - well done for the practical demonstration of the threshold of feeling and beyond. Very brave, but I trust that he bought those resitors from a reliable source. This is beginning to be the go to centre for electrical safety practical advice: very well presented and researched.

[benkerr]

when i was given nerve conduction test to check for carpal tunnel syndrome, they fire 57 mA between elbow and fingeertips.most people are ok, except electricians, we just can't sit still when we feel current tingling like that, the automatic reaction is to pull away.

Another automatic reaction, is when poking around in a live board with the right hand, the left hand automatically goes behind your back, to avoid dangerous current flow

[followthetrawler]

40 years ago as a Power Electronics apprentice I was taught a phrase. "It's the Volts that jolts, it's the Mills that KILLS" - worth remembering, so I have for 40 years...

[therealjammit]

The heart:
A collection of 20 billion locked oscillators.

[Greg]

For a non-medical fellow, you did a superb job of explaining defibrillation.

[amakyusa]

I have to say. I really like when you get caught in your thoughts and knowledge, and goes talking and talking. Highly informative and in a very well articulated way. Gotta love your videos.

[johnhenderson]

Thank you Clive. That was the best demonstration of what current can do. I have been very careless with electricity in the past, with my mentor giving warning but having not experienced anything too scary I thought it was unnecessary warning. I had been shocked before with wiring light switches live and such. I finally wised up ( a bit) when talking with commercial electricians with the shocks they have experienced. I realized that my shocks were minor because of the limited load on the circuit( I.e. a light bulb). When working with motors or full circuits is when things get dangerous. Real enjoy the year downs and the schematics.

[pistolade]

as an electrical technician i enjoyed the "introductory" bit. we're trained to keep a hand behind our back if working on particularly dangerous equipment because of the very reason of risk of shock through your chest. we've even had someone die because an electrical fan in the door touched their lower back and went up through their arm. only a few years back and something a normal tech would never even think about. its crazy how easy it is to die in industry especially when youre working on things that arent operating properly. definitely made a subscriber out of me even though this is four years old yesterday. cheers

[jimenezdecosta]

It is so nice to watch video's from someone who researches and knows his trade. I've learned alot from this video. I went to first aid training but your explanation covered much more subjects about the AED, even decided to buy one myself.

Keep up the video's, they're awesome and informative.