I was just thinking about this the other day. Sometimes, when a power plug is not looked at for some quite, it loosens and the pins are very exposed. Why is there no shield around this? Isn’t this a hazard? What would happen if someone accidentally put one hand on each pin Or something?
You and anomalous1 need to have a chat…
The prongs on a standard plug are about 3/4" of an inch apart. For an adult to grab only one prong with one hand and only the other prong with the other hand would require very deliberate action. If they were dumb enough to choose to do this, they’d be risking a potentially lethal shock.
Babies have a slightly better chance of doing this, but they’re more likely to grab both prongs with one hand and get a painful (but nonlethal) shock. Don’t leave your baby unattended.
And possibly a very nasty burn
I’ve been buzzed a few times and got nothing more than a brief sting. Since the OP said “mains”, perhaps they are British which uses 240 vac, and that would pack a lot more punch then 110.
Dennis
As time has gone on the level of shielding has improved with different plug and socket designs. Depends upon which country you are in, and how much scope there is in the base deign for shielding.
European sockets have been designed for decades with a round recess that matches the plug, so by the time the pins are exposed the plug is disconnected.
UK and Australian/NZ plugs are now made with an insulated portion of the pin, so that if you put your hand in behind the plug you will only connect with the insulated portion.
IEC plugs have a built in shroud.
I don’t know much about what has been done in the US, but it seems not a lot. The basic plug design is not really amenable to much change or improvement for safety.
I’ve accidentally put my finger across 240 volt mains in the past. So the current went through a couple of cm of flesh. Not exactly pleasant. (Teach me to poke about inside the dark depths without thinking.) But there is no doubt, in other circumstances I would have been pushing up daisies.
Here here!
That made me laugh!
I am really comforted to know I was not alone in these questions. I kept thinking “surely someone else has wondered this, seems unsettling how potentially dangerous stuff we surround ourselves with is.” and there he is!
I was under a lot of stress at the time so it gave me a bout of OCD about it, I could care less now/not more than anyone else. Reading about the stuff just piqued my interest in learning more about electrical stuff, its magical, not to be feared.
As for Dude_robert’s question, the other posters covered it, I was all freaked out thinking an ajar plug was going to spontaneously combust. Then I thought, how many years have I must have been alive with a loose plug in the house, nothing happened, and it won’t. I came on here (deliberately) for that question, even though I read the Straight Dope in the Chicago Reader for years. My take is, change the breaker out with a GFCI breaker or GFCI/AFCI combination like I did, it’ll put all your worries to rest. Nothing is going to happen.
Cheers!
Because the basic design goes back to the early 1900s, and safety standards back then were nowhere near as strict as they are today. While it is recognized as a potential shock hazard if you grab both conductors, no one has thought it enough of a problem to justify the bizillions of dollars it would take to replace every plug and socket in the U.S.
Also, it doesn’t matter if the plug is drawing power or not. The shock hazard is there as long as there is voltage at the socket.
Plugs and sockets in the UK have a better design.
If the OP was in the UK, what he describes is extremely unlikely due to the far safer design of plugs and sockets. I have, over my many years, received a few 240V shocks. Clearly non lethal (since I am still here) they usually made me pull away quickly and left a tingling sensation for a short time. I believe that the major injuries from 240v shocks occur when they make people fall off ladders etc.
I know of a man who lost his life with a 120 buzz. 120 can kill.
50 volts can kill.
There is a school of thought that suggests that lower voltages are more likely to bring about fibrillation than a solid arrest. This makes the lower voltages more dangerous in that it is harder to revive someone in fibrillation. On the whole however, I would doubt any idea that any voltage is more or less safe.
About the only sure thing is that a shock from a 33kv feeder and you are never coming back. Some shocks hurt, some will stop your heart, some will disrupt enough internal chemical pathways that you are properly dead, and some will cook you from the inside. Any first aid course will tell you that any electrical burn is serious and must get a trip to ED. A little burnt patch on the skin can be the marker for a slab of cooked flesh underneath and life threatening injuries.
It wouldn’t take bazillions of dollars. Just one company to manufacture recessed outlets and/or insulated prongs. Then usage will slowly spread throughout new construction.
We’ll never get to round prongs, because they won’t be backwards compatible, but I’m not seeing why we couldn’t recess outlets (they’d have to be big to accept heavy duty plugs), insulate (flat) prongs, and possibly add shutters to the hot and neutral on grounded outlets.
In fact, I’m not sure why this hasn’t happened already. We already updated our outlets to be both polarized and grounded, neither of which were backwards compatible with what came before. Recessing the outlet an inch back and insulating prongs seems pretty minor in comparison. Of course, the safety increase is pretty minor, too. Do we have any statistics on fires or injuries caused by European safety features that US sockets lack?
You can buy all the recessed receptacles you want already. They make them for mounting flatscreen TVs.
It’s unlikely they will ever be required by code; getting shocked by semi-exposed plug prongs just isn’t that common a failure mode.
As you say, recessed outlets are readily available. Though the specific design isn’t a tight fit around the male plug body because there is no standard on the exterior shape of a male plug body. The prong size, shape, and spacing is standardized. But not the shell around it.
For forward fit one could use all recessed outlets and gain some small percentage of safety. As offset by the difficulty in grasping the plug body down in the recess and thereby encouraging ignorant users to remove the plug by yanking on the wire.
They’re also an abject failure for anyone wanting to plug in a wall wart.
For retrofit you have the additional problem that the outlet module is deeper and typically needs to be used with a deep junction box, not a shallow one. Given the high level of optimization for extreme cheapness in construction, shallow outlet and switch boxes are the norm in a lot of areas.
Not unless someone has been tugging at it.
Plugs dont back out on their own
There is such a thing as a loose fit. Simply remove the plug and manually bend the prongs out a fraction and then plug in. Continue until the fit is snug.
More likely a child will experiment with placing a piece of metal across the gap.
Heck, my little brother got some serious electrical burns when he was maybe 3 or 4 years old while playing around with a power strip in our bedroom as kids. I have no idea what exactly happened, but it was just 110v and causes some rather spectacular burn marks and blistering on his hand. I managed to unplug it or pull him off the strip or something before any further damage could be done.
I touched an extension cord prong once (feeling around in the dark) when I was about 8, for about 4 or 5 seconds. I guess the best description is “shock”. It hurt like heck up and down my entire arm and it felt like my arm was vibrating, sort of like pins and needles. There was a residual soreness for a minute or two afterwards. (North American 120V) AFAIK I probably touched one prong, or maybe one and I was grounded - concrete floor.
I have read about electricians with a sense of humor who will hold a live wire and grab a passing co-worker. Some people have a warped sense of humor, but this indicates it is not really serious - unless, I assume, you have a heart condition or something.
I heard of some guy who was hunting and climbed a transmission line tower to look for moose. He got within 6 feet of some serious voltage and it arced through him and knocked him out. Afterward, the scuttlebutt was that they were doing work on the line, so when it tripped they did not turn it back on. Otherwise he would have died, instead of being knocked out for a while; and it might have killed his buddy who went up afterwards to get him. You don’t even have to get very close to those high voltage lines to get in trouble.
Another fellow I heard of was working with an industrial connection at 600V. They worked on a wood floor a dozen feet from the regular structure. He was lowering the device with a push-button control, and leaned against the next device on a different phase. the current went through the control, through him, and through his back. Fortunately, he dropped the controller when he started to shake after a second or two, breaking the circuit. Witnesses said his leather jacket was smoking at the back, so presumably that was the most resistance and reduced the voltage going through him.
Oh, I’ve gotten electrical shocks many times as a kid, and that’s more-or-less how I’d describe it. Also, it’s a bit like when you hit your funny bone and have that tingly, vibrating sensation in your arm. I had it happen again to me a few years ago when I jumped into a snow bank and my entire leg just collapsed under me with that tingly, vibrating feeling. I thought I had pinched a nerve or something, but I realized later that there was a broken power line a few feet away. :eek:
You could get them 70 years ago, too. Look for electric clock receptacles.
One was installed in my parents house, built in 1954. Along with receptacles that had tamper-resistant shutters keeping the blade openings covered when not in use.
This stuff has been around for decades.
But people don’t buy it, because it costs more. (And often, is less convenient to use.)