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Zinc !!


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I had a zinc problem in my shop last summer, I put a crucible in the forge that somehow had zinc in it, and I didn't know it. When I saw the bluebell flames and smoke, I took it out of the fire, opened both sets of barn doors in my shop, and went outside. I didn't feel well the rest of the day, and I think the zinc is the reason. At least I noticed it when I did!

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Glenn
I would think the difference is one pipe was welded hotter than other and it is possible that the weld on one pipe has penetrated deeper than the other. Sometimes the weld will look good but if you hit it with a hammer it will brake off quiet easley.
Jeff under no circumstances should you ever weld or heat zinc. It is highly toxic and cancerous i will never allow it in my forge again.

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Frank this was definately zinc, galvanized coated, but old enough that you could not tell by looking. The welding flared the zinc and little white threqds were floating everywhere in the air. I left the area holding my breath.

Question was to start a discussion for the blacksmiths that had not encountered such things before. Photos help identify the problem.

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Glenn:

The little white threads floating in the air were only a small portion of the problem, what is more hazardous is the stuff in the fumes that you can't see. These are particles that are able to pass directly through the lungs and into the bloodstream. A while back I did a written blueprint on Toxicology but I can't find it in the blueprint section now. Maybe it got lost in the move, but perhaps now is a good time to publish it again. I still have the original copy let me know if you need it.

Woody

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Maybe we should get a link to MSDS posted. Material Safety Data Sheets for industrial materials and their reactivity for absorbtion, combustability and such. I know its a web site but dunno the addy. Little help anyone??

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More information on Fume feaver is available at:
MILLS WELDING & SPECIALTY GASES WEB SITE - Safety Tips (dead link)

There is also another thread on the I Forge Iron site called PPW-Fume Fever. Both are very much worth reviewing.

This thread was started (including a photo) as zinc once again tried to sneek up and take me by surprise. First experience I had with zinc took 3-4 days to recover, and it was very much a learning experience. I read up on zinc, fume feaver, heavy metal poisioning and etc and thought I knew enough to avoid the hazards. The 2nd time (yes it got me again) I recognized the zinc, but not in time. It took 2-3 days to recover from only a light exposure. I do not play the zinc game, if it is zinc I try to avoid it. But avoiding the problem does not mean the problem does not exist. It means you must always be aware of the problems related to zinc.

This was the reason for this thread, zinc once again showed up in a very unlikely place. This does not mean you must avoid zinc or working with the material, just that it is a life threatening danger and you must treat it as such.

Keep the suggestions coming as the new blacksmith may have no knowledge on the subject and we need to have the information on the site he can use as a reference.


Fume Fever
Zinc oxide fumes cause a flu-like illness called Metal Fume Fever. Symptoms of Metal Fume Fever include headache, fever, chills, muscle aches, thirst, nausea, vomiting, chest soreness, fatigue, gastrointestinal pain, weakness, and tiredness. Other elements, such as copper and magnesium, may cause similar effects. If you encounter these symptoms, contact a physician and have a medical examination / evaluation. A google search on Zinc, fume fever, heavy metal poison, etc. will provide more information.

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Every time I talk to someone new and welding comes up, I mention the danger of zinc or galvanized. If we would prepare (clean up) the surfaces before welding, we might spot this more often. Maybe hit the area with at least a wire brush until the bare metal is clearly visible?

Another way to approach this is to assume that ALL metal that you weld is poisonous, and do your very best to be upwind, well ventilated, etc. in addition to cleaning up and examining the surfaces to be welded.

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This is probably my worst experiance with galvy. A few months ago I was taking the advanced raising/metals class at NMU. Another girl in the class was making a chair for one of the projects. The welding and forging areas are adjacent in the same open area, and I was using one of the forges, perhaps 30 feet from the welding deck.

The girl in question was torch cutting about a dozen curved pipes which were clearly galvanized. The only safety precuations she took were to put the vent hose over the cutting area, and put a hankercheif around her face. The vent was about as useful as the hankercheif, since it was over the cutting area, and white smoke was pouring out the other end of the pipes.

She was told by several people that what she was doing was a Bad Idea, but plowed on anyway. I left after a while because I didn't want to breath what she was spewing into the air.

She finished the chair, and no one got the galvy shakes, but I wasn't very pleased with what happened. If she wants to cut galvy pipe, that's her business, but when there's 10 other people in close proximity, that's just irresponsible.

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Ok, this might be a dumb question, but I hadn't known that zinc and other plated metals were so toxic. All the more reason to study smithin' under a real smith as I've been planning.:P

However, today when I was with my daughter over at the local high school pool, I noticed that the bleachers around the pool had railing that was welded, AFAICT, but it was galvanized.

This got me wondering, since the galvanizing process must plate the steel with a toxic coating, which I assume shouldn't be put into a forge or welded either.

First question, is all galvanized steel toxic? I read the link Glenn posted and they refer to galvanized.

Second question, if it is toxic, is this common for welding shops to weld steel together and then cover it with galvanizing? Or do they weld the galvanized with some special type of respiratory protection and/or ventilation (however that might be)?

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Zinc metal is not that toxic to touch; however vapourized zinc is toxic to *breath*.

If you go over to link removed at the request of anvilfire you can read about the death of a smith due to breathing zinc fumes.

Many welders get the "zinc shakes" from welding on galvanized metal; the more so since it does build up in the body so that lower exposures sets it off later.

To weld it safely you need a fume extractor or do it outside witn a good breeze to carry the fumes away from you.

Thomas

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Glenn, thanks. Education is the key. You can't make a lot of folks care but thanks for posting the information. :) The hazards of this trade ( welding/smithing) are numerous and your disclamer should be read by everyone. I miss Jim Wilson. He was a sharp fella but like many of us, careless.

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"and some eventually developed pneumonia" So MFF doesn't kill but it can lead to pneumonia which does kill. Having once missed an entire month of work due to pnemonia one *summer* I will try to err on the side of caution. (sort of like jumping off the top of a building---the jump doesn't kill you it's the sudden stop at the end...)

Shall we now address the effects of cadmium which is sometimes confused with galvanization on metal scrap and also what Be does to people who accidently use it in bronze/brass scrap? (Be scares me; I purged my brass scrap of anything that *might* contain Be when I read up on it!)

Thomas

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Thomas, let me respectfully rephrase your example. Jim and others jump out of airplanes all the time. With the proper training, most people can do it safely, and live. An unfortunate few get killed by the sudden stop when things go wrong, or safety is lax.

I tried to limit my search to only zinc so the results would be specific to the problem. There are many more blacksmithing hazards, Heavy Metal Posioning being a nasty one. Like jumping out of an airplane, people work with heavy metals on a daily basis, but take the proper safety precautions to avoid that sudden stop.

The following is the extended excerp from one of the references. Please read the entire article by clicking on the link.

eMedicine Specialties > Emergency Medicine > Toxicology June 28, 2006

The classic acute occupational heavy metal toxicity is metal fume fever (MFF), a self-limiting inhalation syndrome seen in workers exposed to metal oxide fumes. MFF, or “brass founders ague,” “zinc shakes,” “Monday morning fever” as it is variously known, is characterized by fever, headache, fatigue, dyspnea, cough, and a metallic taste occurring within 3-10 hours after exposure. The usual culprit is zinc oxide, but MFF may occur with magnesium, cobalt, and copper oxide fumes as well. A neutrophil alveolitis ensues, with hypoxia, reduced vital capacity, and diffuse bilateral infiltrates seen on radiographs.

The pathophysiology of MFF appears to be a direct toxic irritation. Treatment is supportive and effects generally resolve within 24 hours. The diagnosis of MFF is based on a history of exposure and must be clearly differentiated from the true chemical pneumonitis that occurs after exposure to metal fumes from cadmium, manganese, mercury, and nickel. These exposures are clinically indistinguishable from MFF in the early stages but tend to progress to ARDS and cause significantly more morbidity and mortality.

Toxic effects from chronic exposure to heavy metals are far more common than acute poisonings. Chronic exposure may lead to a variety of conditions depending on the route of exposure and the metabolism and storage of the specific element in question. For example, chronic exposure to cobalt dust has been associated with the development of pulmonary fibrosis that can lead to cor pulmonale. This hard metal pneumoconiosis has been described for other metal dusts. Chronic inhalation of high levels of cadmium also causes both fibrotic and emphysematous lung damage, but it also has major effects in bone and kidney. Itai-itai (ouch-ouch) disease—a syndrome of chronic renal failure and osteoporosis described in the Fuchu area of Japan—is often attributed to high levels of naturally occurring cadmium in the soil coupled with increased industrial exposures around World War II.

Exposure to copper can lead to its accumulation in liver, brain, kidney, and cornea, leading to the classic impairment and stigmata of Wilson diseaseand Indian childhood cirrhosis. Many of the heavy metals have been implicated as carcinogens in the setting of chronic exposure.

The most common species implicated in acute and/or chronic heavy metal toxicity are lead, arsenic, and mercury. Overall, lead is the most significant toxin of the heavy metals. Industrial decisions, such as the addition of lead to paints, dyes, and gasoline, have created an epidemic of lead poisonings. Lead is a naturally occurring substance and can be found in organic and inorganic forms. Inorganic forms of lead typically affect the CNS, peripheral nervous system (PNS), hematopoietic, renal, GI, cardiovascular, and reproductive systems. Organic lead toxicities tend to predominately affect the CNS.

The inorganic forms of lead are absorbed through ingestion or inhalation, whereas organic lead salts are absorbed through the skin. Only about 10% of an ingested dose is absorbed in adults, but the absorbed percentage may be much greater in children. Lead absorption is enhanced by deficiencies of iron, calcium, and zinc.

Under typical conditions, lead is absorbed and stored in several body compartments. Five to ten percent is found in the blood, most of which is located in erythrocytes; 80-90% is taken up in the bone and stored with the hydroxyapatite crystals, where it easily exchanges with the blood. Some authorities list the half-life of lead in the bone as long as 30 years, while others estimate the lead half-life in bone to be 105 days. Generally, excretion of lead is slow, with an estimated biologic half-life in soft tissues of 24-40 days. The remainder of the stored lead is found in soft tissue, notably the kidney and brain. The primary route of excretion is through feces (80-90%). To a lesser extent, lead is excreted in urine (10%). Lead passes the placental barrier and is found in breast milk. A correlation exists between lead toxicity and fetal wastage, premature rupture of membranes, and sterility.
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Thanks for the heads up on the zinc- nasty stuff indeed. I used to weld full time and all of the hazards are the main reason I refuse to make my living that way anymore. Even with respirators and ventilation systems it's just not worth it when I can make just as much money doing something else, ANYTHING else. Once I quit welding (mostly galvanized) I felt much better right away. I won't go back to it full time. Period. Dan:D

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This might not belong in this thread, since it is zinc, but something I've wondered about is when you take old car parts, like leaf springs, and if they were old and contain paint on them, there could be lead in the paint.

Wouldn't that cause problems in the forge? We all have learned that lead is not good, and I have to imagine that burning lead paint couldn't be good for anyone.

Can anyone confirm or deny this as something else I should keep in my mind. Typically the leaf springs are all rusted with no paint whatsoever, but it seems a spooge bath (electrolysis) might be in order before putting some of that stuff in the forge. Or better yet, just find non-painted steel.

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If the paint contained lead and it was removed with a grinder sander wire brush or burned off in the forge it would put lead particles in the air. If you breathe these, you will get lead into your system. Lead is shed by the body, but slowly so it is possible for toxic concentrations to build up in the system. The amount of exposure you get will be determined by the concentration of lead in the air and the length of time you spent in the contaminated atmosphere. Remember that the lead will not magically disappear, it will settle with the rest of the dust in your shop and every time the dust is stired up, you will get more exposure. The effects of the exposure depend on many things, you size and weight, your general health, your gender, the amount of exposure etc. There has been more than one police officer who was in charge of an indoor firing range suffer the effects of lead poisoning from the small amount of lead that is vaporized each time a lead bullet was fired on the range.

When it comes to heavy metal poisoning, Cadmium is even worse. Sources of Cadmium exposure would be heating grade 8 bolts that are Cadmium plated, or using welding rods containing Cadmium. NiCad rod, which also contains Nickel another toxic heavy metal.


Woody

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In regards to galvanized and/or zinc, I have seen lots of folks use a galvanized quench tank. And more what got me wondering about this is if galvanized pipe was used for the blower and/or ash gate of a tuyere?

I 'spose a quench tank won't be nearly a problem, but if someone was to accidentally use galvanized pipe/connectors on the tuyere, I can see that presenting a problem. Is this the case?

This thread got me at least looking at different materials at the hardware store, and there's a lot of galvanized, most of it.

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If your blower is hot enough to burn off the zinc your smithy has just burned down!

The firepot may get hot enough in use---depending on how it's made and how you are using it, so the connection just under it may have issues as well. But I have never had the ashdump section hot enough to burn zinc in the 25+ years I have been smithing on a number of commercial and home built forges.

Thomas

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If your blower is hot enough to burn off the zinc your smithy has just burned down!
burnin' down the smithy...not good...
The firepot may get hot enough in use---depending on how it's made and how you are using it, so the connection just under it may have issues as well. But I have never had the ashdump section hot enough to burn zinc in the 25+ years I have been smithing on a number of commercial and home built forges.
In trying to understand all this stuff, I hadn't really paid attention to that before, and did look at some fittings at the hardware store that I went back to check and saw some were galvanized, which threw up a red flag to me...so I learned something, maybe I should take a vacation this week to gloat over learning something...;)
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