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View Full Version : "Friking LASER BEAMS" and safety -- looking for goggle information!



Grind Hard
10-08-2011, 09:44 PM
Ok... I am being cross-trained to operate the FRIKING LASER!!! machine at work. This is an enormous flatbed... over which flies a CNC-guided laser head. It cuts super-accurate shapes in sheet-metal... which we turn into actual products that customers pay for.

It's a CO2 laser... when it pierces a sheet to begin cutting there is an intense laser flash.

I am told that I do not need "special goggles" for this laser... then again I was told that the coolant I use in my machines was "harmless." Somehow I ended up with crippling dermatitis, no joke. Thanks to communication, MSDS sheets, information from doctors and a phone-call to the material supplier that was fixed forthwith.

Anyway, I would prefer to head this off this time. :) Don't want to suffer terminal eyeball failure or optic-nerve irritation or something along those lines.

What is out there goggle-wise. I see different colors, degrees of reflectivity, and so on. Specifically I watch the laser while it cuts the first pieces of a run, so I am exposed to the flash for about 5 min out of every hour eight hours a day.

Advice and information would be greatly appreciated!

Dr Stan
10-08-2011, 10:00 PM
Lasers are very cool to operate, but you are right to be concerned about the flash. Find out who supplies the safety glasses for your shop and insist the company provide you with the proper eye protection. If you are in a union shop get your steward or local president to help you. If the shop is not organized contact OSHA post haste.

rythmnbls
10-08-2011, 10:15 PM
CO2 lasers emit light in the infrared spectrum, so the flash you are seeing is most likely the material being cut reaching high temps, not laser light.

Infrared wavelength doesn't pass through the cornea, lens, and vitreous humour of the eye so retina damage is unlikely, but the front of the eye can be burned, as can any exposed skin.

Acrylic, glass and polycarbonates are reasonably opaque to infrared, so they could be used as safety goggles.

HTH.

Steve.

Gravy
10-08-2011, 10:24 PM
Ok... I am being cross-trained to operate the FRIKING LASER!!! machine at work. This is an enormous flatbed... over which flies a CNC-guided laser head. It cuts super-accurate shapes in sheet-metal... which we turn into actual products that customers pay for.

It's a CO2 laser... when it pierces a sheet to begin cutting there is an intense laser flash.

I am told that I do not need "special goggles" for this laser... then again I was told that the coolant I use in my machines was "harmless." Somehow I ended up with crippling dermatitis, no joke. Thanks to communication, MSDS sheets, information from doctors and a phone-call to the material supplier that was fixed forthwith.

Anyway, I would prefer to head this off this time. :) Don't want to suffer terminal eyeball failure or optic-nerve irritation or something along those lines.

What is out there goggle-wise. I see different colors, degrees of reflectivity, and so on. Specifically I watch the laser while it cuts the first pieces of a run, so I am exposed to the flash for about 5 min out of every hour eight hours a day.

Advice and information would be greatly appreciated!

Advice but no real information: You are right to be concerned. If the laser can cut sheet metal, the reflections can fry your retinas (rentinae?). Suggest that the person who said "no special goggles" join you for your next shift along with their nearest infant relative. After all, if it's safe for you it will be safe for them. (Yeah, like that's gonna happen).

Edited to add: Maybe it's perfectly safe if it all works as intended. After all, what could possibly go wrong? Just look at the perfect safety records of the Titanic and Hindenburg.

Grind Hard
10-08-2011, 10:39 PM
I have been with this company long enough to know that hardball will get me nowhere.

Lead by example is the best solution for this situation. If I start wearing them then other people will ask me why. Then they will ask where they can get them.

This method has worked on several safety related issues here... and it will work on this one too.

Gravy
10-08-2011, 11:11 PM
I have been with this company long enough to know that hardball will get me nowhere.

Lead by example is the best solution for this situation. If I start wearing them then other people will ask me why. Then they will ask where they can get them.

This method has worked on several safety related issues here... and it will work on this one too.

Good point. I may have been a trifle overly dramatic. So how about "What eye protection is appropriate for direct or reflected exposure?"

I have no idea, but I'm interested in the answer.

macona
10-08-2011, 11:13 PM
Like mentioned above, the CO2 wavelength is so long it is completely absorbed by plastics, glass, and just about everything most people consider transparent. In fact, items we consider opaque, like silicon and germanium, are partially to fully transparent to IR at these longer wavelengths. Germanium, which is a silvery metal, is used for lenses on CO2 lasers and high end temp sensors.

The flash from a CO2 laser piercing is harmless. Any scattered light would not even penetrate your cornea nevertheless cause retinal damage that is caused from visible, near IR, and longer UV wavelength lasers.

Bmyers
10-08-2011, 11:18 PM
What does the OEM suggest ?

Evan
10-09-2011, 01:13 AM
What eye protection is appropriate for direct or reflected exposure?

There is no recommended eye protection against direct exposure other than steel shutters. It is able to cut metal, eyeballs are trivial. The machine is designed with multiple interlocks to prevent operator exposure to direct or reflected light. It is probably oxygen assisted which is in part what creates the flash like a cutting torch. If it makes you feel better light green gas welding glasses will cut the IR at all wavelengths by 97% or more.

jhe.1973
10-09-2011, 01:13 AM
Hi Everyone,

I couldn't resist telling of the sign that was posted in a university's lab where they used lasers.

WARNING!

DO NOT LOOK DIRECTLY INTO LASER WITH REMAINING GOOD EYE!

:D

Grind Hard
10-09-2011, 04:52 AM
It is probably oxygen assisted which is in part what creates the flash like a cutting torch. If it makes you feel better light green gas welding glasses will cut the IR at all wavelengths by 97% or more.

We run mostly nitrogen. We reserve the oxygen for thick steel plate.

So what I am taking away here is the flash is harmless and I shouldn't worry about it? Is that the general consensus here? :)

jugs
10-09-2011, 05:37 AM
We run mostly nitrogen. We reserve the oxygen for thick steel plate.

So what I am taking away here is the flash is harmless and I shouldn't worry about it? Is that the general consensus here? :)

You should always worry about your eyes - (& flashers offering sweets :D )


ALWAYS wear the appropriate protection

SteveF
10-09-2011, 08:26 AM
So what I am taking away here is the flash is harmless and I shouldn't worry about it? Is that the general consensus here? :)

Just me but when my health and safety is at risk I couldn't care less about the general consensus from a group of largely anonymous people with unknown technical qualifications. Seems like there was a good lesson with your coolant experience.

Get and read the manufacturer's safety documentation.

Steve

Grind Hard
10-09-2011, 10:39 AM
I am going to grab a pair of "casual welder" goggles tomorrow. These are tinted/coated lenses that we issue folks when they have to work near the welding department or when the welding department comes to them.

They reduce stray arc-flash to a tolerable level. They DO NOT enable you to watch the welder.

Better than nothing at all while I research this further.

Tony Ennis
10-09-2011, 10:44 AM
Seriously? Are we serious?

I wouldn't turn on the machine until I knew for sure I wasn't going to blind myself. I'd go to the manufacturer and get the facts.

+1 steveF

Grind Hard
10-09-2011, 11:14 AM
Well it's been running since 2005 and no one has gone blind-blind yet... On the other hand everyone who runs it eventually needs corrective glasses.

Could be coincidence.

Anyway, I am not taking a "stand" on this. I mentioned upthread that will get me nowhere with these people.

wierdscience
10-09-2011, 11:16 AM
Nothing more needed than ordinary safety glasses which you should have on at all times anyway.

wierdscience
10-09-2011, 11:17 AM
Well it's been running since 2005 and no one has gone blind-blind yet... On the other hand everyone who runs it eventually needs corrective glasses.

Could be coincidence.

.

I would point out that everyone given time will need corrective glasses operating Lasers or not:D

Evan
10-09-2011, 02:06 PM
There are available IR safety glasses with high visual transmittance. They look almost clear with over 50% visual while cutting IR to 0.00001%. Check with suppliers of laser protection eyewear. They will probably cost around $100 or so.

I also discovered that ordinary glass lenses with ruby AR coating cut IR to almost nothing based on the total reduction of heat felt when looking at a very hot fire in my wood burning stove. Not very scientific though.

bob ward
10-09-2011, 09:14 PM
Your best source of information as others have said is the manual that came with the machine. The machine maker's lawyers and safety people will have it all covered.

huntinguy
10-09-2011, 09:31 PM
http://www.lasersafety.com/category.cfm?market=5&catid=1

just an FYI: some fiber-optic servers and amplifiers use lasers too... wish my instructor would have told me BEFORE we started working with them! There were no warnings on the box...