UV Glasses for Mc Gizmo UV lights

more_vampires

more_vampires

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https://en.wikipedia.org/wiki/Arc_welding#Eye_damage
Exposure to the brightness of the weld area leads to a condition called arc eye in which ultraviolet light causes inflammation of the cornea and can burn the retinas of the eyes. Welding goggles and helmets with dark face plates—much darker than those in sunglasses or oxy-fuel goggles—are worn to prevent this exposure. In recent years, new helmet models have been produced featuring a face plate which automatically self-darkens electronically.[16] To protect bystanders, transparent welding curtains often surround the welding area. These curtains, made of a polyvinyl chloride plastic film, shield nearby workers from exposure to the UV light from the electric arc.[17]

CPFer FritzHID tells me that he likes #12 welding eyewear for working with arc, which provides broad spectrum uv. I've actually got goggles and a full face mask, but was looking for high end glasses.

What are the symptoms of "Arc Eye?"
http://www.ccohs.ca/oshanswers/safety_haz/welding/eyes.html
Certain types of UV radiation can produce an injury to the surface and mucous membrane (conjunctiva) of the eye called "arc eye," "welders' eye" or "arc flash." These names are common names for "conjunctivitis" - an inflammation of the mucous membrane of the front of the eye. The symptoms include:


  • pain - ranging from a mild feeling of pressure in the eyes to intense pain in severe instances
  • tearing and reddening of the eye and membranes around the eye
  • sensation of "sand in the eye" or abnormal sensitivity to light
  • inability to look at light sources (photophobia)
The amount of time required to cause these effects depends on several factors such as the intensity of the radiation, the distance from the welding arc, the angle at which the radiation enters the eye, and type of eye protection that the welder or bystander is using. However, exposure to just a few seconds of intense UV light can cause arc eye. These symptoms may not be felt until several hours after exposure.
This is when you know you've got a problem, but it's already too late.
 
more_vampires

more_vampires

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Blocking UV with regular glass:

This is super hit-and-miss. Some glass is effectively transparent to UV, some not. Most glass won't stop broad spectrum UV, but it can help.
https://en.wikipedia.org/wiki/Ultraviolet
Ordinary window glass passes about 90% of the light above 350 nm, but blocks over 90% of the light below 300 nm.[22][23][24]

http://donklipstein.com/carbarc.html
The UV content contains significant UV-B and some UV-C (shortwave UV) which is hazardous to skin and eyes. Ordinary glass stops these, but plenty of UV-A (longwave UV) gets through glass, and this may be hazardous to eyes at high intensities.
So at 365nm, we cannot use regular window glass. :(

http://www.curtain-and-divider.com/industrial-welding-curtains/welding-curtain-walls-2/
Welding curtain walls generally cover larger areas where it is not feasible to use portable welding screens. These curtains are fabricated from Vinyl which will block the harmful UV rays from welding
If it can stop broad spectrum UV from arc welding, it can stop 365nm.

Since the light is non-collimated, this may or may not be enough. Not sure yet.

I'm still thinking that arc welding goggles but NOT gas welding goggles would be the ticket.
https://en.wikipedia.org/wiki/Welding_goggles
Welding and cutting processes, including arc welding and cutting, as well as brazing produce intense ultraviolet (UV), infrared (IR) and visible light wavelengths. The UV and IR wavelengths cannot be seen and can produce eye injury without the victim realizing it immediately. Extremely dark filters of the proper sort are needed for the welder to be able to look at the intensely glowing metal being welded.

Auto dim eye gear will likely not trip with a UV light as it's looking for the arc striking. It won't "turn on," most likely.
A filter suitable for gas welding, for instance, should not be used for arc welding. Face masks which are self dimming are available for arc welding, MIG, TIG and plasma cutting, and allow better vision before the arc is struck and after it is extinguished.[6]
Still hunting high end laser eye glasses.
 
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RedLED

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Appreciate the kind words, RL.

To clarify the clarification :)

The laser eye shields aren't cut-and-dry 365nm and no other frequency. Noir has a great many charts and charts and charts showing the RANGE of wavelengths blocked and what ranges are transmitted through the eye shield. To go with the example, there is no "365nm eye shield."

https://en.wikipedia.org/wiki/Laser_safety
Wavelength rangePathological effect
180–315 nm (UV-B, UV-C)photokeratitis (inflammation of the cornea, equivalent to sunburn)
315–400 nm (UV-A)photochemical cataract (clouding of the eye lens)
400–780 nm (visible)photochemical damage to the retina, retinal burn
780–1400 nm (near-IR)cataract, retinal burn
1.4–3.0μm (IR)aqueous flare (protein in the aqueous humour), cataract, corneal burn
3.0 μm–1 mmcorneal burn
--------------------

-------------------


Whew! There's a mountain of this stuff to sift through. Really looks extremely easy to pick the wrong eye shields, waste a couple hundred bucks and have a false sense of protection.

I spent a few minutes hunting for 365nm glasses, I flipped through about 50 spec sheets. Haven't found one I'd call suitable yet.

Research, research, and research some more. Strongest I've found yet is OD7, but don't like the ranges I'm seeing.

I need some broad spectrum UV protection for working with home made carbon filament incan and carbon arc, so I'm working towards this as well. I'm along for the ride.

I'm leaning towards welding goggles as arc welding is pretty much like working with carbon arc.


Thank you so much for doing this, I know it is a lot of work, however, overall, it is a good thing for our members who like to install these vials, and it is something I want to work on not just for myself but all the proper presently doing this but, for future Trit. vial installers, some which be unaware that this causes serious and in some cases irepairable damage to their vision.

This could be the most importation and prolific sticky ever to be posted here.

So, could Arc welding goggles work, or could? Also just as an example, for the short duration we zap the vials with UV, could some of the better glasses work for that duration or is damage done in an instant?

Once again thanks for the work, I think it is very important work which I and I am sure many others here appreciate very much, I know I do. I will also keep working in it as well.

Thanks again,

RL
 
more_vampires

more_vampires

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Thank you so much for doing this, I know it is a lot of work, however, overall, it is a good thing for our members who like to install these vials, and it is something I want to work on not just for myself but all the proper presently doing this but, for future Trit. vial installers, some which be unaware that this causes serious and in some cases irepairable damage to their vision.
No problem, friends! I used to be a resident on Answers.com. Old habits die hard. :) We fight together towards the answer. We relish dispelling the darkness. :)

This could be the most importation and prolific sticky ever to be posted here.
Never my intention, in a lot of ways I'm just sharing what I'm reading and enjoy posting it in a thread that's appropriate. Glad to help. It's enjoyable to find a thread where we have common goals, that's a community right there.

So, could Arc welding goggles work, or could? Also just as an example, for the short duration we zap the vials with UV, could some of the better glasses work for that duration or is damage done in an instant?
Damage is cumulative and gets worse the more exposure you get. It's a lot like a sunburn inside your eyes.

Yeah, I'm absolutely positive that ARC welding goggles (but not oxy-ace goggles) would do it. The thing I'm grappling is the cut-off. How light of a shade can we go so as not to trip and fall because we can't see, yet still be protected. The UV damage is sort of an ongoing thing. How long is the curing exposure anyway? If the UV is intense enough, you can get a sunburn from it and need to cover up exposed skin in addition to eye protection.

I'm looking at all options I can think of or find. The welding curtains (not all will block UV) might do it for a non-collimated UV light, but I don't have all that info yet.

The right laser UV glasses will be major overkill, but safe. You'll be able to see almost normally as well with some models. It's going to look pretty dark with arc goggles, there is a tripping hazard.
 
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RedLED

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Well, I just called 3M, and this is what they told me, and I am a skeptic with big companies, they told am ANY of their UV glasses are the tested from 200nm to 380nm, I told them I was working with 365nm, and they said I should be good to as these were the most dangerous of the UV ratings, and anything below 280nm all the way through all the UV spectrums would be safe.

Really? I just don't know. What do you think? I am not ready to believe this at this point in time. I feel like calling back and talking to someone other than a CS Rep.
 
RI Chevy

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Maybe check with an optometrist or call a medical college that specializes in eyes and ask them and see what they say?
 
nfetterly

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I have found that the Bondic cures very fast with the 365 nm Nichia and I just look away when I fire up the LED and hold it on for a few seconds.

The jewel in the thread for me - of course I just order some more Norland on the weekend, but this looks pretty good.
 
RI Chevy

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I wonder if Norland has any information on UV goggles?
 
more_vampires

more_vampires

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Well, I just called 3M, and this is what they told me, and I am a skeptic with big companies, they told am ANY of their UV glasses are the tested from 200nm to 380nm, I told them I was working with 365nm, and they said I should be good to as these were the most dangerous of the UV ratings, and anything below 280nm all the way through all the UV spectrums would be safe.

Really? I just don't know. What do you think? I am not ready to believe this at this point in time. I feel like calling back and talking to someone other than a CS Rep.
The real issue is a spectrograph of the alleged 356nm. What's the actual frequency range? If it's 200-380nm for "any 3m uv glasses," and the emitter is also spewing 390nm, for example...

UV-A goes up to 400nm. Why would supposedly good UV glasses stop at 380nm? UV-A would still get through?

and anything below 280nm all the way through all the UV spectrums would be safe.
I think something's wrong with what that CS rep said. ANY wavelength can be harmful at a high enough intensity. A strong enough exposure of UV can overwhelm any eye protection. Something is better than nothing, but you can't just throw on any old UV glasses for all conditions.

Maybe check with an optometrist or call a medical college that specializes in eyes and ask them and see what they say?
A dentist as well, they work with UV for that conversion stuff they use for fillings now. They have all kinds of safety regs for X ray, I'm sure they are required to know about UV hazard as well.

I wonder if Norland has any information on UV goggles?
You'd think they would.
 
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RedLED

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I have a feeling many workers are not properly protected, we can cover our eyes for 4 seconds for Norland to set, but tradesmen working all day are going to have huge problems some day.

When I travel I notice the TSA use, I forget the name of the light! and the UV reflects back at them off the ID's, that can't be good and no Govt. Supplied eveware to be seen.

It would seem to me that with as much UV being used today, the exact proper eye protection would be available to people?

What nn do dentists use, and on TV shows they spray that stuff then turn in a gigantic UV light, is this a Prop, or something? however they always make sure every one has eveware on?
 
more_vampires

more_vampires

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UV at low intensities isn't damaging unless you stare into it all day.

"Black light," for example, contains UV.
https://en.wikipedia.org/wiki/Black_light
A black light, also referred to as a UV-A light, Wood's light, or simply ultraviolet light, is a lamp that emits long wave (UV-A) ultraviolet light and not much visible light.[1][2][3][4] The lamp has a violet filter material, either on the bulb or in a separate glass filter in the lamp housing, which blocks most visible light and allows through UV,[3] so the lamp has a dim violet glow when operating.[5][6] Black light bulbs which have this filter have a lighting industry designation that includes the letters "BLB".[3][5]

A second type of bulb, which is also called a black light, produces ultraviolet but does not have the filter material, so it produces more visible light and has a blue color when operating.[3][4][5] These are made for use in "bug zapper" insect traps and are identified by the industry designation "BL".[5][6]
Black light sources may be specially designed fluorescent lamps, mercury vapor lamps, light-emitting diodes, lasers, or incandescent lamps.[5][6] In medicine, forensics, and some other scientific fields, such a light source is referred to as a Wood's lamp (named after Robert Williams Wood).
Although many other types of lamp emit ultraviolet light with visible light, black lights are essential when UV-A light without visible light is needed, particularly in observing fluorescence,[4][5] the colored glow that many substances emit when exposed to UV. Black lights are employed for decorative and artistic lighting effects, diagnostic and therapeutic uses in medicine,[3] the detection of substances tagged with fluorescent dyes, rock-hunting, the detection of counterfeit money, the curing of plastic resins, and attracting insects.[4] Strong sources of long-wave ultraviolet light are used in tanning beds.[4] Although the low power UV-A emitted by black lights is not a hazard to skin or eyes and can be viewed without protection, powerful ultraviolet sources present dangers and require personal protective equipment such as goggles and gloves.

https://en.wikipedia.org/wiki/Personal_protective_equipment#Eye_protection
Each day, about 2000 US workers have a job-related eye injury that requires medical attention.[6]

What NMR do dentists use?
Ah HA! :)
https://en.wikipedia.org/wiki/Dental_curing_light#Light_emitting_diode_.5BLED.5D_curing_light
The dental LED curing lights use LED’s that produce a narrow spectrum of blue light in the 400- to 500-nm range (with a peak wavelength of about 460nm), which is the useful energy range for activating the CPQ molecule most commonly used to initiate the photo-polymerization of dental monomers."[6]

The newest[when?]​ LED curing light is the HP (high powered LED light). It is an updated LED curing light that cures material much faster than the Halogen and the previous LED curing lights. It uses a single high-intensity blue LED with a larger semi conductor crystal.[6] Light intensity and the area that is illuminated has been increased with an output of 1,000 mW/cm2.[6] In order to emit such a high intensity light, it uses a highly reflective mirror film that consisting of "multilayer polymer film technology."[6]

The dental curing lights I've seen have a small yellow-orange shield about the size of a snuff can for the operator to look through. I've never seen dental people wear eye protection. The burst are also very short. It's in the few seconds these days, with that 1 watt/cm^2.

They do it often. Do they need protection? Maybe. 1 watt/cm^2 in a power emitter. Small point. Perhaps they're hoping to never look directly into it or reflect it off a shiny surface.
 
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RedLED

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http://web.mit.edu/cohengroup/safety/uv110720safety.pdf

Yes, I am breaking the hot link rules for a darn good reason, as people's eyesight, and future depend upon it, so let it ride. Also, legal, liability may be involved here, do you really want anything to happen to a registered or non member here?

This is is from MIT, one of the world's most revered universities who, got us to the Moon, the internet among many other thing and we really, really need your opinion More_ vampires, can you look this over and advise on this, so no one has serious eye damage.

What do make of this?

This is above my pay grade. However, my neighbor across the street is right as his pay grade! And when I told him about this, his response was "Oh God." He worked on Apollo 11, and the B1 Bomber. Plus he has one one of the most amazing Corvette collections that anyone will ever see, Very smart man. One of our nations best!

All I am asking for is a set of goggles, or glasses safe enough to do this Norland work with no eye damage to people. It can't be that impossible?

CPF...Thanks for letting me avoid the hot link rule this time, as people could be damaging their eyes unknowingly! And I am certain you do not want or need that kind of trouble.


Thanks, CPF!

And all the best to you, and all your members!

RL
 
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more_vampires

more_vampires

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Interesting read. It presents further research, processing it now.

First impression was "my God, they've got a 2 megajoule/cm2 365nm UV-A source?" Then I realized that was only .555 kw-hr. "Only." :)

How to Limit Danger
Whenever you switch to use the fluorescent bulb on the microscope alwayshave the filter in place beforehand!
failure could burn cornea!

Wear protective gloves, sleeves and UV protection glasses when using the UV lamps (especially the 253 nm lamp). Limit direct exposure.
Keep in mind they've got a heck of a UV source in that link. They're saying the level of power they're using can actually degrade your DNA! WOW! :tinfoil:

The best advice in that link is "avoid direct exposure." The take-away from that is don't look directly into the UV source. Dentists never do that. They place the light, hit it, and done. They don't wave it around the room. I think this in of itself is as or more important than what eye protection is selected.

Also, it's time to know what emitter and wattage is being used on the McGizmo UV light. It's the final piece of the puzzle. Only then is it possible to calculate what OD is needed at a minimum. Intensity is a major variable. If we cannot assume the user won't do something you're not supposed to do, such as look directly into the UV or wave the light around and nail themselves on a reflective surface, then we must calculate for a direct exposure. If we assume the user uses safe handling practices, then we can calculate for the scattered exposure from looking at the item being illuminated with the curing light.

Something I often say is "Technique trumps gear, knowledge is more important than gear." A work around to eye protection would be to steady the work piece, place the light, close eyes, hit the light. Mounting the light in a work clamp would be most helpful. That'd probably be fine for a couple shots for a few seconds each. Likely, most of us will not be doing this work all day every day for years.

With a workstand holding the UV and the item to be cured, you know where everything is and could simply drape a heavy black trash bag over it. In that case, we don't even NEED eyewear. The item gets cured, the user receives no exposure.

The McGizmo UV isn't a super-blaster, is it? Polyvinylchloride sheeting (UV blocking welding curtain) draped over a workstand with the clamped light and workpiece could be plenty if the user can be trusted to have the sheeting in place when the light is lit and make no other mistakes.

Also, I finally ran across visible spectrum CLEAR safety glasses. I'm still trying to determine if the OD is strong enough for the intensity, but now it's time to talk about the McGizmo UV light itself.

The American Conference of Governmental Industrial Hygienists (ACGIH) publishes Threshold Limit Values (TLVs),
UV-A (315 nm to 400 nm), the ACGIH recommends 1.0 J/cm2 for periods lasting less than 1000 seconds.
All of their pubs are behind a paywall and require a login. :(

On the plus side, we now have an upper limit for exposure from "the pros."

After all of this reading, I would not look directly into ANY UV high power led emitter. I think that's something we can all agree on.
 
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more_vampires

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https://en.wikipedia.org/wiki/High-energy_visible_light#Blue-light_hazard
Blue-light hazard is defined as the potential for a photochemical induced retinal injury resulting from electromagnetic radiation exposure at wavelengths primarily between 400–500 nm. This has not been shown to occur in humans, only inconclusively in some rodent, primate and in vitro studies.[4] The mechanisms for photochemical induced retinal injury are caused by the absorption of light by photoreceptors in the eye. Under normal conditions when light hits a photoreceptor, the cell bleaches and becomes useless until it has recovered through a metabolic process called the visual cycle.[5][6]

Absorption of blue light, however, has been shown in rats and a susceptible strain of mice to cause a reversal of the process where cells become unbleached and responsive again to light before they are ready. At wavelengths of blue light below 430 nm this greatly increases the potential for oxidative damage.[7] For blue-light circadian therapy, harm is minimized by employing blue light at the near-green end of the blue spectrum. "1-2 min of 408 nm and 25 minutes of 430 nm are sufficient to cause irreversible death of photoreceptors and lesions of the retinal pigment epithelium. ... The action spectrum of light-sensitive retinal ganglion cells was found to peak at 470-480 nm, a range with lower damage potential, yet not completely outside the damaging range."[8] A 2014 study found that LEDs cause retinal damage even in settings where they are used indirectly, such as household light bulbs.[9]
A 2013 in vitro study using shorter blue band spectrum LED lights indicated that prolonged exposure may permanently damage the pigment epithelial cells of the retina. The test conditions were the equivalent of staring at a 100 watt blue incandescent source from 20 cm (8 in) for 12 hours.[10][11]

http://www.candlepowerforums.com/vb/showthread.php?398401-UV-led-makes-you-see-things
EEK! I was not up on UV like I am now when I posted in that thread! I would have immediately said "Don't do that!"

http://www.ncbi.nlm.nih.gov/pubmed?uid=11692615&cmd=showdetailview&indexed=google
MATERIALS AND METHODS:
Young adult rhesus monkeys were anesthetized, and received blue LED exposure from a modified slit-lamp. A 3 mm beam of 0.85 mW was imaged onto the retina through a lens positioned before the cornea and exposure damage was determined at time intervals for 12 to 90 min. Fundus photography, fluorescein angiography(FAG), retinal tomography(HRT), and s-cone electororetinogram(S-ERG) were recorded at baseline, 2, and 30 days.
RESULTS:

Two days after 40 min exposure, there was a grey, discolored region, which was over-fluorescent in FAG, and an incresse in HRT and S-ERG corresponding to the site which was exposed to LED light. In histological examination at 30 days, the LED had caused produced a marked disruption of the disks of photoreceptor cells, damaged retinal pigment epithelium(RPE) apical villi, and a loss of RPE melanin after 90 min exposure.
CONCLUSION:

A threshold level was found around 40 min. This morphological damage may impair function and continuous exposure to blue light is potentially dangerous to vision.
Ouch, damage from 40 min exposure @ .85 MILLIwatts? Wow. 3mm is an extremely tight beam, though. This would be like holding the UV light up directly to your eye, except I think the McGizmo UV is quite a bit more than .85 milliwatts.

http://www.ncbi.nlm.nih.gov/pubmed/...nel.Pubmed_DiscoveryPanel.Pubmed_Discovery_RA
Light damage research began during the early years of laser light exploration. There is a clear and significant literature that identifies an easily demonstrated retina-pigment epithelium pathology which is associated with short wavelength exposures below 520 nm. Recent interest has expanded because of the growing evidence for a blue light contribution to the retina aging process by way of a poorly understood chemical process(es) that involve circulation, oxidative reactions and the spectral absorption properties of the pigment epithelium. New powerful sources of relatively inexpensive blue energy have become available as a family of light emitting diodes. In this experiment, we examined funduscopic, angiographic and scanning laser tomographic measures of the retinal-pigment epithelium response to LED and laser spectral blue and infrared emissions closely matched in wavelengths and delivered under carefully matched circumstances. Ten retinas in normal young rhesus monkeys were locally exposed to various energy density values at 458 nm (Argon laser) ranging from 5 to 54 J cm(-2). Eight rhesus eyes were exposed to LED irradiation with a peak wavelength of 460 nm ranging from 9 to 62 J cm(-2). Similarly, a matched infrared (IR) laser and IR LED pair were used to expose an additional ten eyes for comparison of the long wavelengths. IR irradiance ranged from 21 to 306 J cm(-2). There was no response to IR exposure in any of the eyes. Blue light exposure results were measured from the color fundus photographs, scanning laser tomographs and early- and late-phase fluorescein angiogram responses at 2 and 30 days after the exposure. Results scores were accumulated for the four measures at the two time periods. The resulting lesion scores when plotted against the exposure in J cm(-2)showed no demonstrable effect at irradiance lower than 10 J cm(-2)and near 100% effectiveness for irradiance greater than 30 J cm(-2). The most sensitive and enduring indicator of change was the late fluorescein angiograms. Nonparametric statistical analysis of the scores from the two samples support the conclusion that there is no difference in the consequences of LED and laser light exposures under these matched conditions.
30 J cm(-2) sounds like bad medicine.

http://www.candlepowerforums.com/vb...l-to-the-eyes-(if-one-looks-directly-into-it)
 
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more_vampires

more_vampires

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The TL;DR summary for dummies:
NEVER look directly into a UV emitter, laser or led. Even if you have UV eye protection, this is something you're not supposed to do.

Don't do it. From what I understand, the McGizmo UV is quite capable of doing damage.
the conclusion that there is no difference in the consequences of LED and laser light exposures under these matched conditions.

Thanks to CPFer FritzHID for getting me started on the road to learning about UV hazard. He insisted that I need to know about it. The 55 watt HID is fun. :)
 
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more_vampires

more_vampires

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All I am asking for is a set of goggles, or glasses safe enough to do this Norland work with no eye damage to people. It can't be that impossible?
Impossible? No.

Complicated? Yes.

It's not just the goggles. The goggles do nothing, as they say.

It's a combined system. The eye wear OD hinges upon beam intensity, focus, and the cumulative exposure duration. If you're looking directly into the focused emitter at arm's length you will need massively more OD than if you have the light off, aim it, turn it on for a few seconds to cure the Norland, then turn it off. There's a lot of variables.

If the flashlight is highly polished, you're going to need a higher OD again.

The science answer to this question hinges on a great many aspects of science. Reflectivity of the flashlight being cured is also a factor.

We could err on the safe side and get the highest OD we can. The danger is when the protective gear isn't good enough for the threat.

The Simple Answer: Get a pair of arc welding goggles, cover all exposed skin, set up a work stand, run the light with a heavy duty trash bag over it to block all light emitted. There is zero way for a light output such as a UV flashlight with power led to hurt you at this point. You'll have trouble seeing, so a solution for that is the work area to be extremely well lit. Don't walk around with the welding goggles on if you can't see. Some of them have flip up shades, those would probably be best. Is there such a thing as "too safe?" :)

Could you just simply use the welding goggles? Most likely so due to the power levels involved. A UV flashlight is orders of magnitude weaker than a welding arc.

If it isn't overkill yet, then you're just not using enough. :)

Also, welding goggles are cheaper than NoIR products. :)

Thanks for patiently wading through the CPF UV Hazard thread. :)

Anything else I can help with? :laughing:
http://www.candlepowerforums.com/vb...PF-UV-Hazard-Thread-Protect-your-eyes-and-DNA
 
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