This from an Electrical Technician:

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50mA will kill you. 30mA might well do so.

As others have said - its all down to the current (amps). Dry skin is an alright (I use the term loosely) insulator - plenty of resistance, so not much current flow (assuming you're acting as an earth path). You'll probably get away with it. Probably.

Wet or sweaty skin (nerves from working on live electrics maybe?) has a low resistance, so you get a lot of current flow. Bang, you're dead.

If you manage to connect yourself in series with another electric load that's drawing current - you're definitely dead. (Dave here: so if you touch a live plug prong/wire from an appliance/light that is switched on…This appertains to your Edit.)

A fuse or an MCB protects against overcurrent. If you have a 13A fuse in your plug, by the time it blows, you'll probably be dead (remember 50mA = 0.05A). An RCD measures the difference in current in the live and neutral cores. If they differ by more than the "trip" value, they trip.
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From me: Dry skin may be a 'good' insulator, but burnt skin is an EXCELLENT conductor and with AC your muscles go into spasm at 60hz if you grasp a live wire - so you cannot let go. Your heart also tries to synch up with this rhythm causing death.

Try to understand, as little as 15mA across your heart can stop it - and you need someone there with medical expertise to bring you back.

Also remember that many older houses do not have Circuit Breakers in the UK/Europe, and that if fitted and you use an extension cord with one fitted, the two combined cause a noticeable lag in the time it takes to 'trip'.

I was an Electronic Shielding Engineer/Quality Manager, using testing equipment running at ultra-high voltages. I don't mess around with household electrics.

Dave.

I see, so an electric fence is not dangerous because it isn't constant, what if that applied to an outlet? If an outlet was with intervals inbetween, would it be like an electric fence?


Also, what I've gathered, in terms of constant electricity, the most dangerous combinations are:

Very high voltage with low current, since apparently this has a lot of punch. 50.000 volt at only 0.1 A (or is it 1 mA?) can kill.

Medium/high voltage with medium/high amp, this is what an electrical socket consists of.



very high current with low volt is apparently not that dangerous. Is this because the volt is so low that it can't push the current through a body?

This is why I am unsure whether not an electric outlet is capable of pushing all its current that its capacity potentially allow it to hold, through a human body It has to push 0.1 - 1 amp at a time? Because that is all the 220 volt is capable of? If it conducted all its 10 - 15 amp, everyone would die by accidental shock from electric outlets, wouldn't they? So current doesn't matter to some extent, if the volt is relatively too low?

The electric fence is not dangerous because it is not constant and it has low amperage, 0.5 amps or less, usually 0.1 amps. A 220 volt circuit like in Europe can have 20 to 30 amps available just like a 110 to 120 circuit in the US can have 20 to 30 amps available. The available amps is just that, available. What flows is dependent of the resistance and draw. The voltage is constant. So a 220 volt circuit always deliver 220 volts. A 120 volt circuit with 30 amps available powering a USB charger for an iPhone will only have 0.15 amps to the transformer and 5 volts at 0.5 amps or less flowing to the iPhone.

A stun gun or taser can deliver 20,000 to 150,000 volts. Some even go into the millions of volts. But, they range from 1-2 to up to 5 milliamps. 0.005 amps. They do not kill but they disrupt the electric signals sent to muscles so the target is either weakened or incapacitated. But, a stun gun flows between the two electrodes, not to ground. So, it is not like an across the chest electric shock. They can be dangerous for someone with a weak heart or if they are used for too long.

But, back to the household outlet. The electricity flowing from an outlet can kill you, whether it is 120 volts or 220 volts. But, you will feel the shock. If you do not feel a shock, you were not shocked.

I suggest you consider getting an outlet tester. It is a simple device that plugs into the outlet. You push a button on it and it tells you if the outlet is properly grounded, if it has a working GFCI/RCBO/RCD or circuit breaker. In the US, they sell for $5 for a simple one to $30 for one with extra features.

In some locals, the fire department or other public safety agency can test the outlets for you.

A fuse or circuit breaker without a GFCI/RCBO/RCD will not protect you from a dangerous shock. But, a working GFCI/RCBO/RCD will protect you.

You should not look at electricity as safe or dangerous. It is all to be considered dangerous. The low voltage electric circuits that are not dangerous are not commonly used in a house except for things like a door bell or air conditioning and heater controls.

So, stay away from electricity and use proper procedure when you plug or unplug something. Turn it off first.

Minimac,
People don't get electrocuted by outlets because they are made of non-conductive material and are earthed, or double earthed for safety (in case the 'live' wire develops a fault). You have already worked out that the air resistance is too great to conduct a current.

Dave.

Okay so I figured out why it sparked, when other appliances is plugged into the extension cord before I connect the extension cord itself to the power outlet, it will spark inside the outlet if, for example, a computer or monitor is connected to the extensiord cord. Dunno exactly why this is, but I presume it's because of some kinda overload? Anyways, if nothing is connected to the extension cord, and I THEN plug it in an outlet, it will not spark. However, it causes intense amount of heat in both scenarios if plugged halfway into the outlet. I'm just worried that simply because it makes spark sounds that it can actually arc your finger if it comes too close to one of the metal prongs.

It's just that I'm so concerned about this due to I've heard that being shocked by an electrical outlet can cause you to develop neuropathy and such. On the other hand, some people laugh at electricians being shocked by outlets saying: "They're bound to have it happen" to them at some point. Is this true? That most if not all electricians prepare themselves to get their fair amount of shocks during their career?

Now when I think about it, I think I was shocked some years ago by a faulty extension cord, but that wasn't from the outlet in the wall, instead from one of the outlets in the actual extension cord. I think I accidentally inserted my hand into the sparking arc that was produced, but it wasn't really more than a burning feeling in my finger. If a shock from an outlet is dangerous it would hurt a lot throughout most of the body right? How can I be sure no internal organs has been heated?

Does the arcing sparks emitting from outlets conduct constant flow? Or is it only static electricity that exists for a mere 1/1000 of a second or something?

Oh and, what if supposedly your head touched the ceiling while getting shocked? Could it potentially travel through your head?

People tend to perceive electricity as an ultimatum it seems, either you live with no real residual symptoms or you'll die because of the heart giving out.

Minimac,

You are mixing things up. If something is plugged into the outlet or extension cord and THAT ITEM IS TURNED ON, it draws power. When you disconnect the plug, this flowing power will arc across from the outlet/extension cord to the plug ONLY when the the prongs are just breaking contact.

There is no overload. If the item is NOT TURNED ON, there will be NO ARCHING.

It will not try to arc to your finger because YOUR BODY IS NOT TURNED ON DRAWING POWER.

A momentary shock at your finger where you quickly pull away to end the shock DO NOT CAUSE Neuropathy.

Any electrician who plans on getting shocked is not a good electrician. An electrician should never be touching live exposed wires with his bare hands. There are insulated pliers and other tools for safely working with live wires. But, a good electrician would know how to avoid getting shocked. He would know that when he needs to work with a live wire, there are steps he can take to minimize his risk.

If you were shocked enough to 'heat' internal organs, you would have need an emergency trip to the hospital or a casual trip to the morgue. There are no shocks that you walk away from that damage internal organs.

"Does the arcing sparks emitting from outlets conduct constant flow?" The arc is momentary while the electricity is trying to flow across the gap. The sparks that splatter do not have an electricity in them. They are just very small pieces of molten metal burning up. Yes, metal burns up. If those sparks touch you, you will not be shocked. They might leave a small pin prick size burn because they are very hot.

"Or is it only static electricity that exists for a mere 1/1000 of a second or something?" It is not static electricity. The arc exists for as long as the gap is small enough for the electricity to arc across. In some cases, if that arc lasts too long, a fuse or circuit breaker will shut the power off.

Your head would have to make a contact to a ground (earth) for electricity to flow from your hand to your head. A ceiling is insulated with paint and other things that make it a poor conductor so no ground would be made.

What you need to remember is simple. DO NOT PLUG OR UNPLUG AN ITEM WHILE IT IS TURNED ON or you risk causing a spark from the arcing. The arcing will not shock you if you keep you hands on the plastic or rubber parts that do not conduct electricity.

I just don't fully understand how there can be arcing between the receptable and the plug? According to Mythbusters, the air can conduct electricity at a distance of 1 cm every 10.000 volt. So how can 220 or 240 volt creat an arc? Is it because of the plug prongs material having low resistance? Arcing would never happen to you as easy as with the metal prongs?

Oh and wait, so, draw or no draw, the risk and danger of the electricity remains the same?

The distance of the gap is likely only 0.01 to 0.02 cm across. The two pieces are actually touching but not continuously. One piece drags across the other with momentary breaks in that contact. The arcing happens during those momentary breaks in contact.

For example, if you wiggled the plug apart, you likely made contact and broke contact as you wiggled the plug. A plug would have line A and line B plus a ground (earth). (in the US it is hot and neutral plus a ground if 120. It would be line A and line B plus a ground in an old 3 prong 220/240 plug and with a neutral wire in newer 4 prong 220/240 plug) You might pull the plug so that the line A prong separates but the line B prong is stuck. You wiggle the plug and the line A prong makes momentary close contact and arcs before you succeed in removing the line B prong. But, this arcing would only happen if the appliance or light is on.

I have no idea what you mean when you say "Oh and wait, so, draw or no draw, the risk and danger of the electricity remains the same? "

btw, Receptacles and plugs are designed to handle this arcing in momentary increments. If a plug repeatedly arcs as you plug it in, it has likely been damaged and should be replaced. Sometimes, an extension cord end will weaken and cause arcing so the extension cord should be replaced. If a light flickers and you hear a sizzle coming from the plug, unplug it and get it repaired or replaced.

But again, THIS WILL NOT HAPPEN IF THE APPLIANCE OR LIGHT IS PROPERLY TURNED OFF FIRST.

What if I have wet hands and insert or pull a plug? Will the odds of an arc jumping a gap to my hands/fingers increase then? Or does dry and and wet hands make no difference in how long the electricity can jump a gap through the air?

Don't touch a plug with wet hands.