Jump to content

Forge UV


Recommended Posts

Hi guys, just a quick query.  I've seen a number of mentions of using welding spectacles when forge welding, but should I be wearing some form of eye protection when working at forging heat?  If so, what would interfere least with seeing the colour of the steel?

 

Cheers,

 

David.

Link to post
Share on other sites
The UV output within a forge can permanately damage your eyes .I must wear protective eyewear on my job each minute I'm there and have gotten used to it. It's easier to me to judge temp while wearing an approved UV (dark) pair of glasses. Dark enough to watch the heat,light enough not to hinder vision at the anvil. My local welding supply has various shades that are impact resistant as well. They don't really help me any but some  eyewear these days are quite fashionable too :D
Link to post
Share on other sites

There is some anecdotal information from the glassblowers community that long term exposure to the UV radiation of a gloryhole can affect ones vision, especially night vision.  It's not the kind of flash burn problem you get from a welder, but a cumulative effect over a period of years.

 

I had some Dydidmium lenses made up, but the color shift was a problem, as well as the crane-like structure I needed to keep my head erect due to the weight of the glass lenses ( I run about 20/900, so the cokebottle lenses I need for my prescription weigh a ton in glass, thank the gods for plastic.).

 

It's a grain of salt problem.  Perhaps over a lifetime staring into a forge will cause a problem.  On the other hand, something else may take you out of the game long before that one gets to be a problem.  My eye doctor was not all that concerned.

 

Geoff

Link to post
Share on other sites

Geoff, I think you should light a fire under your eye doctor and see if he squirms a little.  This is not an unknown problem at all.  

 

But let me speak from personal as well as professional experience.  Sometimes my forge gets hot enough that I can't see anything in there without a dark lens.  I've gotten used to using a No. 5 welder's lens all the time when looking into the fire.  Some folks may need more (No. 7), some less (No. 3).  Dydimium lenses are a good expensive choice too.  It's tough when the eye requires something heavy.  Are contact lenses a choice you could make?  Then wear the cheapo welding glasses?  I'm always scratching them up, or sweating and they fall off or hot stuff sticks to them I didn't know was there.  That's when I say a heartfelt prayer of thanks for wearing them.  

 

Sure, it's not perfect colors as compared to daylight, but I'm not looking at pure "color" by that time anyway.  The lens helps reduce the glare so I can see the surface of the billet and the condition of the flux.  I can identify welding readiness by that and the absence of "shadows", ie. the color match between the billet and the side walls of the forge.  I don't need an absolute color range anymore.  The eye adapts to the light coming into it.  Your brain will learn the colors it needs with experience.  

 

UV exposure is a known, and well established, risk.  Anyone using an arc welder for any length of time can speak to the results on exposed skin.  It's the same as sunburn.  It doesn't take a long period of exposure to prove this either.  Flash burns are the short term consequence of high intensity and unprotected exposure.  The cornea generally heals quickly even though it's very uncomfortable.  I would rather avoid this situation altogether because of that.  Multiple flash burns will have the consequence of increased risk of scarring of the cornea leading eventually to the possibility of corneal transplantation.  

 

UV exposure can and will cause skin cancer over the lifetime.  It can be a problem if left untreated, e.g. disfiguring surgical scars etc., but is not likely to cause mortality by itself unless ignored.  Worse is something like melanoma but that is a whole different situation.  I am not aware of any reports of UV linked to corneal cancer.  

 

UV light has been implicated in cataracts over a lifetime of exposure.  Cataracts are probably the most definitive result of chronic UV exposure, but they can be caused by other things like diabetes as well.  Retinal damage is not as conclusive, however, the lens of the eye does focus vision directly onto the most sensitive and important visual structure at the back of the eye.  Most of us have relatively fast reflexes that will prevent too much injury (blinking, turning the eye away) but that is not a guarantee of injury prevention.  

 

Ya know guys/gals, wearing safety glasses when looking into the fire should be obligatory.  There was some discussion that just a simple clear plastic lens would eliminate (99-100%) the UV exposure from sunlight.  I can not find any research that suggests a clear safety lens would completely prevent UV forge or welding exposure.  Even if you don't care about UV light enough to wear colored lenses, there are little hot bits that fly out once in a while even from the best built and best protected forges.  Worse, you're welding and using a hammer...what are the odds that a molten glob of flux will head for your eye?  Something like that landing in your eye will put pause to a career or avocation in a heartbeat.  There isn't enough water in the eye to quench it quick enough.  

 

Grumbling about color changes or learning to adopt safety practices that are good common sense?  Hmmm, a very important decision you must make.  As long as you should be wearing spectacles why not add enough color to prevent a lifetime problem?  But humans adapt pretty quickly to funny colors in their sunglasses.  Welders and bladesmiths can too. :D

Link to post
Share on other sites

I always wear safety specs when I'm forging (and grinding, and etching), but it seems like an upgrade to a UV blocking pair would be a good idea, even if my forge isn't quite as hot as Mike's. (Mike, I forget, is your forge powered by nuclear fission or fusion? :) )

 

Thanks Guys.

Link to post
Share on other sites

Fission? ..... Nuclear Fishin is great for night time, the fish glow in the dark

 

 

:P

Link to post
Share on other sites
Guest Richard Furrer

Hello All,

Visible light is about 400-700 nm

UV is 12.5 to 375 nm

Near IR 770 to 1300 nm

NOW

didymium filters from 430 to 980 nm and are specifically designed to absorb bright yellow sodium flare (589 nm) which occurs when heating glass. A gold coating is used as the gold (just like on astronaut helmets) reflects the bulk of the harmful rays. Since we as smiths do not have sodium flare the didymium is not the best choice.

 

It is my understanding that the Amer Welding Society recommends a shade #3 as the minimum welding shield for forge work.

 

 

I refer you to this:  http://digitalfire.ab.ca/cermat/education/152.html

 

"4-Injuries Due to Infrared Radiation:

 

Potters may be exposed to this type of radiation.

 

Wavelenghts greater than 750 nm. in the infrared spectrum can produce lens changes.

 

La "cataracte des verriers"( glassblower's cataract ) is an example of a heat injury that damages the anterior lens capsule among unprotected artists. Denser cataractous changes can occur in unprotected workers who observe glowing masses of glass or iron for many hours a day.

 

Another important factor is the distance between the worker and the source of radiation. In the case of arc welding, infrared radiation decreases rapidly as a function of distance, so that farther than 3 feet away from where welding takes place, it does not pose an ocular hazard anymore but, ultraviolet radiation still does. That is why welders wear tinted glasses and surrounding workers only have to wear clear ones.

 

Conclusion:

 

When we speak of type of exposure, potters look at their cone packs for very short periods of time in a repeated way, more often nearing the end of firing; and also according to the use of other methods for measuring temperature, like the concomitant use of a thermocouple and a reading device.

 

So, these " short-term " exposures are spaced by quite longer " exposure-free " periods and the sum of the former does not correlate with the concept of "many hours a day".

 

We have searched the literature pertaining to Occupational Health and Safety and have not found a single case of presumed " ceramicist’s or potter’s cataract ", even if the trade of potter is quite older than the one of glassblower.

 

Therefore, I do not think that any of the above types of radiation present a threat to potters.

 

It is a good thing, mainly at high temperature, to wear lightly tinted industrial grade safety glasses to better visualize cones(ocular ergonomics) and also to reassure those who are more worried.

 

These glasses also offer a better protection than typical sun-glasses in case of projection of hot dust particles from a gas kiln when looking through the peephole in a soft brick door.

 

By the way with ageing, most if not all of us, will suffer from cataracts of the "senile" type.

 

The progress or change and the related reduction in vision is usually quite slow.

 

Nuclear sclerosis-an increasing density in the central mass of protein-causes a myopic change than can be corrected by changing glasses for some years-in many instances restoring vision to near normal."

Link to post
Share on other sites

local hardware store sells saftey glasses for outdoor work, 100% UV protection, but not that dark, more a greenish color.

Tried them for forgewelding, and they do just very few interfere juding the steel colors, but you can stare for a while into the forge without getting this "flashes" in the eyes.

Link to post
Share on other sites

Dang it's only February and the UV/didiyium thingie has resurfaced .

 

weldors use welding lenses, glass blowers whatever.

 

#### good advice from an old crusty weldor, given to me at the tender age of 17.

 

DON"T STARE AT THE LIGHT!

always wear safety glasses

Link to post
Share on other sites

You can go to any welding shop and get UV-rated safety glasses that are not that dark, and if you get the amber colour and they are ansi-approved uv-blocking safety glasses, all the concerns about both uv protection AND colour correction will be 100% answered.

4 bucks and they look cool.   After about 3 minutes your eyes will totally adjust to the amber colour and you'll read colours just fine, and most people, better than they ever did before.

 

Thats the whole point of uv-amber lens saftey glasses, it's why they are amber.

Link to post
Share on other sites

Here we go Sweany!  :;):

 

From what I have read, and from what Sweany posted on the CKD forums a while back, a decent shade of green welder's lenses will actually do the trick.  From my perspective though, I want to see more of my surroundings than the welder's lenses will generally allow.  I want a lense that will let me view welding temps inside my gas forge and not be so dark that I have to remove it to get to the hammer.

 

{Comparison between glassblowing & metalsmithing applications, from MIke Aurelius at Auralens}

 

Glassworkers use a furnace at about 2100 F with a ceramic pot holding anywhere from 10 to 100 pounds of molten glass. These furnaces are either electrical or gas fired.

 

Glassworkers also use a 'glory hole' which can run from 2200 F to 2600 F where the glass in process is being re-heated and molded. Glory holes are typically gas-fired, usually by propane, and are refractory-lined with fiber or frax as insulators.

 

(By the way, I'm talking about traditional glass blowing here, not the lamp or flame workers.)

 

Glass and steel will emit essentially the same radiation at the same temperature - what makes them different is the chemicals in each material. Since glass contains large amounts of sodium, when exposed to high temperatures, you get the classic sodium flare (bright yellow flame) that didymium was originally developed to filter out.

 

UV is hardly ever a concern UNTIL you get up to about 5000 F. At that point, the furnace/steel/refractory becomes a true black body radiator.

 

Radiation always starts at the red end of things and moves to the blue end of the spectrum. Therefore, IR is always a concern, and UV is hardly ever a concern (unless you are working materials that generate UV by themselves - such as quartz when working with glass).

 

Ignoring for the moment the welder/brazer, the basic metal worker needs to concern himself/herself with protecting the eye from intense deep IR radiation. At the same time, you also have to filter down the bright intense visible light coming out of the fire, not to mention the colors of the metals.

 

Right now, with the available filter materials we have, you basically have two directions you can go: traditional welding filters and composite filters, such as our AGW-186 and AGW-200 filters.

 

Traditional welding filters are excellent IR filters, and cut the visible light, but may cut them too much. We have found that for most workers, a shade 2.0 or 2.5 is the perfect choice. They provide a minimum of 96% IR filtration; 2.0 transmits about 30% visible light, and the 2.5 transmits about 15% visible light. Here's a link to the filter information page on my site: Filter information

 

The only problem with these filters is that it is difficult to read your color base or temperatures as you work the metals. This is where the didymium or next generation AUR-92 come in. These filters work by filtering out specific wavelengths of light that are unnecessary to normal vision. The main cut is the sodium yellow spectrum from 575 nm to 600 nm. There are also some secondary cuts as well, and these secondarys are enhanced in the AUR-92 filter, which is one reason it has become widely accepted in the flame/lamp working (for glass) industry because of the ability to see the color temperatures in the glass as you work it.

 

Unfortunately, didymium/AUR-92 are lousy IR filters. Each filter transmits at least 80 % (didymium is the worst at over 90%) IR energy. This is where the AGW-186 and AGW-200 full coverage lenses come in.

 

The AGW-186 takes the AUR-92 material and adds a 'clear' IR filter from the Schott KG series. This results in a total elimination of IR energy from 800 nm on out.

 

The AGW-200 filter is AUR-92 plus green welding glass. This filter is used where you want to cut down the total visible light as well as cutting the IR, but maintaining your color recognition.

 

You make a very good point about being able to see your workplace, and this is one reason why the AUR-99 Shade 2.0 is so popular with the traditional blower. They can look into the glory hole while reheating their glass, and then sit back down at the bench and pick up their tools and get back to work without having to wait for their eyes to adjust.

 

One last thought about eye irritation and injury. Since we've started doing this (10 + years now), I've been keeping a very unscientific survey about those people who experience eye irritation/injury and those that don't under similiar circumstances. Remember that this is very unscientific! I am seeing a correlation between eye color/skin color and eye injury/damage. It is beginning to appear that people who have brown eyes and darker skin tend to have fewer incidences or delayed incidences of eye irritation/injury than people who have blue eyes, light skin. The factor at work here appears to be the melanin content of the body. Genetics seems to give the equatorial peoples (African, Hispanic, Indio origin) a higher resistance to IR damage than those people whose ancestors were from further north such as our classic Minnesota Scandanavian blonde blue eyed folks. There is medical case history which shows a higher incidence of 'glassworker cataract' among the early glassworkers of England than those of Murano, Italy.

 

Let me add a caution here: this is extremely early in the process of putting this information together. If you are a 'classic' Italian, please don't discard your glasses! IR damage to the eye is cumulative, and if you are brown-eyed, you are still getting damage, it just may take longer for the damage to appear. I present this discussion merely to be sure that everyone is well informed and up-to-date on what is going on in our research. If you are blue-eyed, the information IS showing that you need to not only protect your eyes, but your skin as well.

 

Well, I've rambled on enough for tonight. Digest this and let me know what you think.

 

From Auralens

 

This was discussed at length a while back on a CKD Thread.

 

I would certainly welcome more input though.  I currently use didymium, which is better than nothing, but will likely order new lenses in the next month or so.  I'm leaning towrds the AGW-186.

Link to post
Share on other sites

Mike,

 

That wasn't me... that was a quote from Mike Aurelius who runs Auralens, a glassblower's / metalworker's safety glasses shop that was recommended to me by some glassblowers I know.  I have actually heard before that there is no appreciable UV coming off most forges, esp. coal or charcoal where the material itself blocks much of the radiation.  I have always heard that the real concern is actually IR.  I'm sure that Mike would explain himself if you e-mailed him.

Link to post
Share on other sites
I'm using my prescription sunglasses right now for forging. They are amber, and are uv-rated polarized glass. I also rub some sunblock on my face when I do a prolonged session. It seems to help at the end of the day when I'm all shagged out. When I wash up I feel better for having the lotion applied.
Link to post
Share on other sites
I think I might try doing a bit of forging in my speedos ..... this long winter has taken it's toll on my pale skin and i haven't had a sunbed session since last September  :D  :P
Link to post
Share on other sites

I'm sure the glassfolks have well developed knowledge.  I'll see if I can get some info from him.  

 

All I can find shows data for UV emissions from metals not fires.  That info indicates that a metal will emit UV radiation as a portion of it's spectrum if excited to 3000 C. Most of us don't work at those temperatures, or our forges wouldn't.  But that data was for tungsten filaments in a vacuum resisting electricity, very unlike a forge.  But it's the light that does the damage.  

 

As Ric said, radiation damage diminishes rapidly with distance.  The problem is that I've examined folks who were ten feet away from a welder, wearing clear safety glasses, who sustained "welder's flash" after just working nearby.  It's too far for IR and visible light wouldn't do that.  

 

I'm still trying to put together the biochemical references...

Link to post
Share on other sites
O.K. I'll stick my two cents worth in. I don't know anything about all the rating and such, but after getting a painfurl "sunburn" on my eye lid from looking into my welding forge, my wife bought me a pair of safety glasses that said that they blocke uv. They have clear lens and only cost a couple of dollars at Harbor Freight. I don't know how much uv they block, they don't say, but I haven't had a problem since I got them. By the way, after the "sunburn", I checked the forge with the pyrometer and found out I was running it way hotter than I needed to. Now I set it just hot emough to weld and turn away from it while the billet is coming up to heat.
Link to post
Share on other sites

We've had this discussion all over the net different forums and different people.

 

the main concern this time seems to be UV.

Can anyone tell me how long does skin need to be exposed to cause damage.

 

Can anyone tell me how far the UV rays travell from the forge at a harmfull intensity?

 

Like I said before weldors have been using shaded green lenses for oh say probably a hundred years now.

Old weldors do get cataracts, the old weldor that taught me cautioned me abaout looking into the center of the arc (brightest intensity)

 

focus to the side or in front of the arc.

 

Same way with the forge. Don't stare into the light.

 

The weld shops have a #3 or a #5 flip down face shield, made for "burners" guys who use a torch.

 

Personally I use a #3 lense in my safety glasses when I'm forge welding. It's light enough to see the anvil and glance into the forge. The ambers are just a shade too light for my eyes to be comfortable.

Link to post
Share on other sites

I think the issue isn't settled for a couple reasons. First, it hasn't had time to come up on this list.  I personally don't roam a lot of the other lists, so I wouldn't have commented on it.  Second, there seems to me now, to be a bunch of folks who occasionally cry "Chicken Little the sky is falling," when all the facts aren't associated correctly.  

 

There are some welding sites that I've perused this morning that seem to indicate that UV radiation should be treated like any other potentially harmful radiation.  They recommend exposure limits.  They also recommend aramid fiber clothing as this blocks UV from reaching even covered skin.  The research, and a good study too, shows evidence that even covering the skin completely with cotton work clothes allows harmful levels of UV rays to reach the skin.  But we've been talking about eyes.  

 

Even clear safety glasses (glass or plastic) will stop a better than 95

% level of UV.  But without side shields it's possible to have some slip around the lens.  Amber or green glasses will stop the uncomfortable/painful visible light from penetrating the eye.  But they will all stop most of the UV.  Any reduction in exposure is a good reduction.  

 

According to the above study (www.ehime-iinet.or.jp/ehime_e/corp/toyo/ronbun/ronbun.htm, and this is just one of the sites) potentially harmful exposure from welding can occur in minutes, not hours, or days or years.  One of the AFSCME sites also discusses lifetime exposure limits even with protective clothing.  

 

Radiation attenuates with distance based on known math (fourth roots by radius) but the effects are still there even when muted.  As I said, I've seen folks with "welder's eye" who were working twenty feet away (no side shields) who didn't look at the welding flash.  There are reports that the welding flash can be reflected and affect people around corners given a days exposure.  

 

What's the bottom line as I see it today.  Safety glasses should be worn for many more reasons than UV light.  Penetrating injuries or direct burns from hot sparks etc are far more immediately damaging.  Also darker shades are important for comfort alone so that work can get done without fatigue consequences.  

 

Somebody said that we are all subject to senile cataracts due to aging alone and that is true.  But why help hasten the process?  

 

I think this is a very worthwhile subject for everyone in the craft, and I get really curious when unsettled matters show up until I know for myself what the facts are.

Link to post
Share on other sites

Almost any kind of glass will block a lot of UV, but having read what Mike from Auralens and a few other people have said, I feel very comfortable with the idea that UV isn't the concern.  If I remember right, the fellow from Auralens is a doctor.  The burn on the eyelid that someone mentioned could easily be the result of IR, which is heat.  If you can feel it you're getting some.  I've gotten warm, slightly red skin on my hands near the forge but never a tan or a freckle... and I'm a redhead that burns & freckles inside of ten minutes in the sun.  Welders get UV from arc welding because the arc itself produces it... not from the metal.  There's no need to protect your skin when oxy/acetylene welding.

 

One concern about using plain sunglasses is that the darkness will cause your pupil to dilate and receive more IR if the lens doesn't block IR.  Don't know how anecdotal that is, but it stands to reason and I've heard it often.

Link to post
Share on other sites

Mike I agrre on a couple things. UV will #### sure eat up cotton clothes. But I have never had skin damage when wearing a good heavy cotton shirt.

 

I used to run a weld machine to weld nozzles in pressure vessel heads. 3/32" wire 600 amps.

 

The machine set in the center of the nozzles and rotated to make the weld. The light and heat was enough to literaly destroy a cotton shirt. I used a pair of #amber safety glasses and #11 weld lenses , gray taped to apiece of carboard. That way I could shield my eyes and make adjustments to the machine. I didn't burn my eyes, but would sometimes have a flash burn, when my sleeve pulled back from my glove on a long reach.

 

Yep you can get reflection burns to the eyes, yep you can burn the eyes if there is a hairline crack in the lenses.

 

I don't use the popular gold plate plastic lenses cause you can't see the scratch in the plateing. You won't know you damaged your eyes until the next day.  :angry:

 

i've been a damned ole weldor for 26 years.

personally I think staring at a stinking monitor has done more damage to my eyes then all that time looking through some dirty old green glass.

 

Cataracts, farmers are prone to cataracts, dust, dirt ,wind and sun.

 

My eyes show the scars of the damage done to em. Even wearing safety glasses all the time you are working (and I do indeed recomend them, not the cheap crappy kind though)

will not keep you 100% safe, but it may deflect or reduce the injury.

 

Wasn't Samson's eyes blinded by holding white hot iron close to his eyes?

 

Remeber this is discussion, we don't have to come to any conclusions.

 

 

 :cool: wearing my glasses

Link to post
Share on other sites
#### #### I didn't know that #### was such a ####### bad word.  #### that ####!   :;):  [wtf]  [ylsuper]
Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...