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Discussion Starter #1
I just read in a book the following: Never weld any metals that are wet & never weld if you (the operator) are wet.
Next is Never allow yourself to become part of the circuit between the ground clamp & the electrode.

Here are my questions. Wet conditions. What if your working on a surface that is damp or in the rain & the material or the operator or both are damp or wet. What can this do to the person if anything, or is this just a condition that would affect the quality of the weld. I assume water & electrode doesn't work well.

My next question. If you are touching the surface of the material you are welding, like sitting on it, leaning against it, does this make you part of the circuit. What do you need to do to be "Part" of the circuit or inside of the circuit. I see welders all the time standing, sitting or laying on the metal surfaces they are welding & I never seen anyone electrocuted by this.

I know my questions may sound very basic, but the book I'm reading has no explanation describing what happens regarding the two conditions I paraphrased above. Thanks.
 

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I just read in a book the following: Never weld any metals that are wet & never weld if you (the operator) are wet.
Next is Never allow yourself to become part of the circuit between the ground clamp & the electrode.

Here are my questions. Wet conditions. What if your working on a surface that is damp or in the rain & the material or the operator or both are damp or wet. What can this do to the person if anything, or is this just a condition that would affect the quality of the weld. I assume water & electrode doesn't work well.

My next question. If you are touching the surface of the material you are welding, like sitting on it, leaning against it, does this make you part of the circuit. What do you need to do to be "Part" of the circuit or inside of the circuit. I see welders all the time standing, sitting or laying on the metal surfaces they are welding & I never seen anyone electrocuted by this.

I know my questions may sound very basic, but the book I'm reading has no explanation describing what happens regarding the two conditions I paraphrased above. Thanks.
I wouldn’t worry about it at all. Once in awhile you might get at “tickle” but that’s about it.
You can weld underwater!
I have see pipe fitters put their oxy torch under water to create bubbles so they can strike an arc and weld pipes that are half submerged down in a trench.

Just start welding and you will quickly figure out what works and what doesn’t
 

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Normally you will be wearing some type of protective clothing... heavy gloves, protective coat, etc. so the chances of having bare skin against the material you are welding are pretty slim. In addition, typically the piece you are welding is one side of the circuit and your MIG wire (or stick electrode) is the other side of the circuit. While you might touch the work piece I doubt you will be touching the MIG wire or stick electrode with your bare hand and even if you do it's only energized WHILE welding.

It is still always best to observe safe welding practices but it's pretty hard to light yourself up.
 

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I've watched my dad get nailed when he was standing in a puddle and the grounding electrode didn't have a good connection. Good rubber souled boots help a lot. I routinely hold pieces for him and have never been shocked. I have been slightly shocked sweating but again, the ground clamp wasn't working good. ( rusty metal )
 

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Thanks for all the replies to my post. I guess if I use common sense & good safety practices, I won't have to worry about creating a personal electric chair:mocking: The grounding clamp condition & connection appears to be key as part of the safety factor & the quality of the weld.
 

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I've been nailed a few times. I believe most if not all stick welders are isolated from the input power via the welder's transformer.
Getting nailed is pretty much having both the grounding clamp and the stinger in your hands.
 

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It’s all about the resistance or lack thereof. Dry skin is quite high in resistance. Adding moisture reduces that significantly. (So will a cut for that matter).Obviously adding clothing etc increases the resistance immensely. Also the higher the voltage, the higher the chance for something/someone becoming a “conductor” . That’s why with extremely high voltage, extra care needs to be taken with large insulators etc. anything will conduct electricity if the voltage is high enough, even open air.
 

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Ive done quite a bit of welding while sweating profusely. Wet enough I could wring my clothes out after I was done, and never an issue.
I do make sure my ground is clean and good before any welding begins.

Now, I have been shocked several times, mostly by 110, but a couple times by 220. 110 was just a tickle. 220 was definitely NOT just a tickle.

Ive also stuck an .030 mig wire through my glove and into my finger. The part slipped out of the fixture. That was not fun...but it healed ok.
That, like most "accidents", was due to not being as careful as I should have been, or being in a hurry.
 

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Frankly, I'm always more worried about a weld bead splattering back under my shirt.
I always enjoy when it goes down my boot because my pants cuff went up. Dang that hurts and there is no quick way to fix that issue. As far as the shocking, I have been tingled a few times years ago when working in wet conditions but now I always grind a spot to bare metal and clamp a vice grip on it and then hook the ground clamp to that.
 

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I just read in a book the following: Never weld any metals that are wet & never weld if you (the operator) are wet.
Next is Never allow yourself to become part of the circuit between the ground clamp & the electrode.

Here are my questions. Wet conditions. What if your working on a surface that is damp or in the rain & the material or the operator or both are damp or wet. What can this do to the person if anything, or is this just a condition that would affect the quality of the weld. I assume water & electrode doesn't work well. Welding wet steel isn't a problem concerning the weld. That said, you being wet makes you a better conductor so you have to be more careful.

My next question. If you are touching the surface of the material you are welding, like sitting on it, leaning against it, does this make you part of the circuit. Not necessarily! What do you need to do to be "Part" of the circuit or inside of the circuit. Touch the electrode tip and the steel that the ground is connected to with the welding machine turned on, or touch the steel, if the ground clamp isn't making good contact, when you strike an arc. I see welders all the time standing, sitting or laying on the metal surfaces they are welding & I never seen anyone electrocuted by this. Standing, sitting on, or otherwise touching the steel you are welding will not shock you if the ground clamp is making good contact.

So, if the ground clamp is making good contact and you do not touch the end of the electrode on a stick weld system and touch the steel at the same time, you will not get shocked.

I know my questions may sound very basic, but the book I'm reading has no explanation describing what happens regarding the two conditions I paraphrased above. Thanks.
See above.
 

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I always enjoy when it goes down my boot because my pants cuff went up. Dang that hurts and there is no quick way to fix that issue. As far as the shocking, I have been tingled a few times years ago when working in wet conditions but now I always grind a spot to bare metal and clamp a vice grip on it and then hook the ground clamp to that.


I use a big pair of vice grips, but same idea. Glad to know it's not just my noobish'ness with welding. :good2:
 

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...electricity, like water follows the path of least resistance.
Actually, electricity takes all paths. Most of it takes the path of least resistance. Like water!
 

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Put the ground clamp as close as possible to the area being welded as electricity, like water follows the path of least resistance.
Technically, it doesn't. It follows all paths with the amount of current in each path inversely proportional to the paths resistance.

The open circuit voltage of any type of arc welder is typically well south of 100V. It drops way down after the arc is stricken. It depends on the circumstances but many people will feel the open circuit voltage to some degree, especially if their skin is wet. For most people the voltage present is harmless. IF YOU HAVE A HEART CONDITION OR ARE GETTING UP IN YEARS you want to be careful since you may be more sensitive to stray electrical current flowing through your body, and especially since act of welding makes a circuit path from your hand through the heart area to ground either via your torso or the other hand more likely.

Al
 

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Discussion Starter #16
Technically, it doesn't. It follows all paths with the amount of current in each path inversely proportional to the paths resistance.

The open circuit voltage of any type of arc welder is typically well south of 100V. It drops way down after the arc is stricken. It depends on the circumstances but many people will feel the open circuit voltage to some degree, especially if their skin is wet. For most people the voltage present is harmless. IF YOU HAVE A HEART CONDITION OR ARE GETTING UP IN YEARS you want to be careful since you may be more sensitive to stray electrical current flowing through your body, and especially since act of welding makes a circuit path from your hand through the heart area to ground either via your torso or the other hand more likely.

Al
Interesting post above. So if a person has a heart condition like Atrial Fibrillation a.k.a. A-Fib, how dangerous is the stray current flowing thru his/her body & is there a way to measure the amount of current. A-Fib is a condition generally caused by a disturbance in the body's electrical impulses that are sent to the heart to keep it beating in sinus rhythm, When the electrical impulse to the heart is not in rhythm it causes the atrial valves to "flutter" which can cause whirl pooling of blood flowing thru the heart's chambers, which in turn can cause a blood clot being formed & traveling into the lungs or brain. I've only stated a basic explanation of what A-Fib is for those who may not be familiar with what it is.

Persons with A-Fib could have their heart stopped by accidental electric shock or a heavy blow to the chest if it occurs at precisely the right time during the A-Fib event. I guess the question is at what amount of stray voltage does it become a high risk problem of the welder. I'm sure that there are a lot of people out there welding who probably have A-Fib & some may not even know they have the condition which is life threatening.
 

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As I recall from my NREL (National Renewable Energy Lab) safety class; it's the current (amps) that does people in, not the voltage; but we're not talking high voltage transmission lines here. It's similar to an old school car ignition system where the coil pumps out 50,000 volts to the plugs; but the current is so low that you are more likely to be injured from the shocking surprise and getting caught in rotating machinery under the hood than the zap itself. Once again if I recall my NREL class correctly, as little as 50-milliamps at just the right time and location is enough to disturb heart rhythm.

However; I will defer to the electrical experts that know for certain. If I'm full of crap with this post, please educate me as I don't know everything in spite of what my wife says. :laugh:
 

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As I recall from my NREL (National Renewable Energy Lab) safety class; it's the current (amps) that does people in, not the voltage; but we're not talking high voltage transmission lines here. It's similar to an old school car ignition system where the coil pumps out 50,000 volts to the plugs; but the current is so low that you are more likely to be injured from the shocking surprise and getting caught in rotating machinery under the hood than the zap itself. Once again if I recall my NREL class correctly, as little as 50-milliamps at just the right time and location is enough to disturb heart rhythm.

However; I will defer to the electrical experts that know for certain. If I'm full of crap with this post, please educate me as I don't know everything in spite of what my wife says. :laugh:
You are correct it is the current that does the damage to the body, higher voltages just make it easy for the current to flow. One of my more painful shocks was from a 12v car battery that I happened to grab just right on a hot summer day. The frequency (Hz) of the electricity causing the shock also plays a major role in how dangerous the shock is.

Your own body mass has some effect on how much current it will take to cause you harm as well. That's why electrical safety for children is so important. A 50-milliamp shock with cause an adult to curse and yell in pain, but that same 50-milliamp shock will likely cause a small child to stop breathing. A sobering example of this is child drowning deaths in swimming pools. Often times an otherwise healthy and un injured child drowns in a pool from a very low current (less than 20-milliamps) shock that is enough to knock them out. That same shock the knocked out the small child is often felt as just a slight tingle to an adult.

The average household GFCI protection device is designed to shut off when it detects any current leakage greater than 5-milliamps. So please make sure your pools have GFCI protection and you test those devices annually. You know press that little test button that is on them.

As for how this applies to welding, I work in a shipyard where people are welding pretty much 24hrs a day. Welding machines can and do cause painful shocks and burns. Its not often a major injury but people have died from getting bit by a welding machine. Certain weld processes alter both the voltage and frequency of the current going to the lead to maintain arc stability so caution and proper work grounding is always advised.

Here is a link to good chart that shows you just how much different electricity can hurt.
 

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As I recall from my NREL (National Renewable Energy Lab) safety class; it's the current (amps) that does people in, not the voltage; but we're not talking high voltage transmission lines here. It's similar to an old school car ignition system where the coil pumps out 50,000 volts to the plugs; but the current is so low that you are more likely to be injured from the shocking surprise and getting caught in rotating machinery under the hood than the zap itself. Once again if I recall my NREL class correctly, as little as 50-milliamps at just the right time and location is enough to disturb heart rhythm.

However; I will defer to the electrical experts that know for certain. If I'm full of crap with this post, please educate me as I don't know everything in spite of what my wife says. :laugh:
You've got it mostly right, especially about the current being what does people in. I was told to compare electricity to water flow. The voltage is the pressure, the current is the volume and the resistance is the size of the pipe. If the pressure is high enough in a small pipe (high resistance) it will still produce enough volume (current) to be deadly. And if the pressure (voltage) is low but the pipe is large in diameter (low resistance) then the same is true.

It's not a perfect analogy, and is simplistic when you realize all that is going on with a circuit, but it can sometimes light up that lightbulb in our minds.

For contact with a live circuit to be fatal, we have to consider the path of the current and the duration, as well as the amount of current, the voltage 'pushing' it, and the resistance of that path. If it's a millisecond of contact, then you might be fine, but if you are part of the circuit for a greater length of time, it's probably going to kill you or at least cause significant damage; even at lower voltages or current. Consider as an exaggeration that you directly connect a 9v battery to your heart. It may not kill you instantly, but over the course of time, it certainly would do damage.

The problem is that current will burn the tissue and continue doing so long after. It also has a tendency to travel along our own electrical circuits in our bodies, the nerves and nervous system. High voltage can do a lot of damage, but may not necessarily be fatal. I know someone who came in contact with one phase of a 4160 volt circuit. His hand (luckily) was resting against the cabinet (ground) and it only traveled from his finger to his palm. But at that voltage (2400v to ground = medium pressure) it just shredded the tissue in his hand when it exited. Obviously if it had traveled through any vital organs he would have died. Lucky man. (Or maybe unlucky if the first place)

The amount of current can be very low and still fatal if it travels through the heart. So many electricians used to keep one hand at their side it a 'hot' panel so it couldn't travel through the chest.

This is a pretty good explanation, even though it's dated 2002:

eLCOSH : Electrical Safety: Safety & Health for Electrical Trades (Student Manual)

HTH
 
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