The CPF UV Hazard Thread. Protect your eyes and DNA.

So we were discussing how to protect ourselves from UV curing light while attaching tritium vials to flashlights with Norland 61 adhesive.

This is what happened:
http://www.candlepowerforums.com/vb/showthread.php?408696-UV-Glasses-for-Mc-Gizmo-UV-lights

The reason I'm posting this is there may be a flaw in my understanding. Wouldn't be the first time. This is also an important safety issue.

Warning, MASSIVE walls of text and tons of links and SCIENCE in the above thread. Might break out the big screen and a real web browser to read.

So, anyone want to talk about UV and UV protection? The baseline is pretty well covered in the above link.

If you want to just read the summary, here it is.

Never look directly in any UV emitter, never ever hold one directly up to your eye. There's a link in that thread to a medical experiment that caused damage with a miniscule .85 milliwatts with super tight focus at close range. This is the equivalent of holding the light directly to your eye. Never do that, it takes almost no energy to cause damage under that condition. This is an example of direct exposure. Indirect exposure is when you see the light reflected off of an object. Objects with high reflectivity are more dangerous.

There's a link to a medical experiment where 40 days after the exposure, the damage was still there. The threat is real, the damage long term. It's like a cumulative sunburn inside your eyes.

It doesn't matter if it's an led or laser, there's a link to a medical experiment on that as well.

No protective eye wear is good for all wavelengths, except maybe lead but now you can't see. No protective eye wear covers all possible intensities of the wavelengths that they protect against, not even lead.

Forget about sunglasses for protection from UV light. Many makers lie and say it "blocks 100% of all UV," but won't tell you at what intensity. Also, due to the visible light OD (optical density,) it dilates your pupils and makes you more vulnerable to what slips through.

In the above linked thread, we encountered an instance of a customer service rep selling UV glasses who didn't understand what he was saying. That's dangerous.

Above all, don't buy the wrong protective gear! You'll have a false sense of protection and you're going to hurt yourself.

We covered the symptoms of UV exposure and what it can do to your body, from cataracts to the actual destruction of your DNA. Different flavors of ultraviolet light (UV-A, UV-B, UV-C) destroy your eyes in slightly different ways.

Stay safe, friends! All in a day's work for your friendly neighborhood vampire.

Disclaimer: I'm a bit UV sensitive.

Ultraviolet light is dangerous. See, she's wearing eye protection for that flashlight.

Mila herself makes me hurt!
But I digress, yes, UV is extremely hazardous, espc since it can so it's damage without alert. Eyes don't respond to it until after damage is done. Skin doesn't "burn" like IR will do. Etc.
The best defense is knowledge. Know the hazards and the proper defensive measures.
Don't put yourself in danger when ever possible.

FRITZHID said:

But I digress, yes, UV is extremely hazardous, espc since it's damage without alert. Eyes don't respond to it until after damage is done.

Click to expand...

Yeah, the weird feeling of sand in your eyes or suddenly you're getting eyestrain. It's already too late.

Medical tests reveal that your eyes won't be getting better anytime soon. Damage is relatively unchanged even after 40 days!

So, Fritz, what's your setup for protecting yourself against the broad-spectrum ultraviolet light that's put off in addition to visible spectrum when you work with HID?

A relative of mine runs a drive-in. I was working with him for free (well, I was paid in Patron Silver margaritias) and we took off a panel on the active projector. He was subtly wearing protective eyewear and I had no clue what's going on.

He smiled and asked if there was a problem. I had NO IDEA.

You see, it was a really old projector running xenon arc light. There was no safety interlock to disable the light with the PROTECTIVE SAFETY PANEL removed.

He relented, said to look away and maybe close my eyes. He replaced the panel.

Over a Patron Margie, he briefly said to never ever do that. It'd ruin my eyes.

This was my first introduction to UV safety.

Destruction of your DNA by ultraviolet light. UV kills bacteria.

http://www.germsys.com/ultraviolet-uv-lamps-in-254-nm-and-185-nm-range/

The disinfection process uses wavelengths in the UVC range from 240 to 280 nanometers

Click to expand...

UV kills bacteria and viruses by breaking the molecular bonds of their DNA/RNA. It also does this to humans, with damage increasing with the length of exposure and increasing with intensity.

UV splits molecular bonds:

High energy photons emitted by low pressure mercury discharge lamps are able to decompose many chemicals. By means of direct photolysis organic bonds are broken as a result of photon absorption. Photons with a wavelength of 254 nm can split such bonds like O-H, C-H, C-C and C-O. 185 nm photons break even higher energetic bonds like C=C and O-O. The energy equivalent of the VUV radiation (185 nm) is, however, not high enough for the strong C=O bond.

Click to expand...

Organic lifeforms actually hate UV very much. This is why. This is sunburn. This is cancer. This is eye damage. We are made of oxygen, hydrogen, carbon, these are organic chemicals that are part of our construction. UV directly attacks us at the molecular level. UV is decomposing the very substance that your corneas are made of.

UV and skin cancer:http://enhs.umn.edu/current/5103/uv/molelcularmech.html

Ultraviolet (UV) radiation is known to cause distinct mutations in keratinocytes that ultimately contribute to the development of the nonmelanoma skin cancers, which include basal cell carcinoma (BCC) and squamous cell carcinoma (SCC).

Click to expand...

The human body has DNA repair mechanisms. If the damage is too rapid, severe, and frequent then the repair mechanisms fail. The result is incorrect cell divison and mutated cells leading to cancer.

This is why you're supposed to cover all exposed skin while arc welding as arc welding generates quite a bit of very broad spectrum UV in addition to visible spectrums. A sunburn from arc welding indoors is indeed possible.

http://www.cancer.org/cancer/cancer...ion-and-early-detection-what-is-u-v-radiation

My methods vary depending on what exactly I'm doing. I use welding goggles, face shields, and I have some UV block polycarb from an old laser.
Most of the time, I just try to keep the proper housing intact while operating.

My Surefire Hellfighter 1's have no caution about UV light. The Hellfighter 4 has a visible as well as the UV-A radiation https://www.dropbox.com/sh/4bozl6rpzy3y7fi/AADtCSMSIMElwAYgLb8JHC9qa?dl=0 caution engraved on the lens cover.

I'm seeing TV ads for a UV cured epoxy in a pen applicator. The pen has what seems to be a coin battery keychain type light mounted to it, for curing the glue.

Ya gotta die of something sooner or later.

Everything causes cancer these days.
Everything.

So if it aint the food, the water...the air...it's gonna be from the pipes our water comes from or the package our food comes in.

The difference between a daredevil and a stuntman is the stuntman takes precautions and plans his routine. But sooner or later they both break bones.

So if you don't dig on genetic defects, don't go near DNA altering methods or materials. Once you know there are risks, take precautions and let the river of fate carry you to your destination.

Thanks for the tips btw.

I grew up where crop dusters sprayed fields nearby and gov't sprayed for mosquitos...too late for me.

But the younger crowd can certainly gain insight in this thread....if they decide it's wiser being a stuntman over being a daredevil.

FRITZHID said:

My methods vary depending on what exactly I'm doing. I use welding goggles, face shields, and I have some UV block polycarb from an old laser.
Most of the time, I just try to keep the proper housing intact while operating.

Click to expand...

I have a couple of welding goggles (arc, oxy-ace) and full mask (arc rated.) The thing about having a proper housing while operating is an extremely salient point. Having layers of protection for when you make a mistake with one of them is also an outstanding idea from a safety stand point.

Good points.

lumen aeternum said:

I'm seeing TV ads for a UV cured epoxy in a pen applicator. The pen has what seems to be a coin battery keychain type light mounted to it, for curing the glue.

Click to expand...

Yes, there is also the "Steri-Pen" germicidal water purification light. I wouldn't hold either of these things directly up to my eye and just stare at it.

That medical experiment that did damage with .85 milliwatts was a 40 minute exposure. I really get the feeling that both of these devices are running hotter than that kind of amperage draw.

The three big metrics in UV damage: Relative intensity (having the thing right on your eye,) duration (longer is worse,) and frequency of exposures. The damage stacks up, particularly in eyes.

Really bad idea.

A relative of mine has kids that for some bizarre reason like to turn on flashlights and stare directly into them. Apparently, they think it's fun. Keep all UV emitters of any stripe away from children. Don't let them play with your epoxy curing UV light.

bykfixer said:

But the younger crowd can certainly gain insight in this thread....if they decide it's wiser being a stuntman over being a daredevil.

Click to expand...

Yeah, we're not born knowing this stuff, we must learn it (hopefully before it's too late.)

This thread has not gone anywhere...

Now we have the the Convoy S2 with the Nichia NCSU276A 365 LED, which is a 365 nm UV emitter. 3 watts.

There is a standard, but ANSI is behind a paywall:
ANSI Z80.3-1986 standard for UV radiation safety glasses.

I'm looking for clear UV protective glasses to protect my eyes from reflections, so I can see the colors that the UV activates -- looking for urine etc stains & at minerals. What I don't know is if some things re-emit UV above the incident 365 nm.

I get the impression that clear glasses protect up to 385 nm. The yellow tinted go to 400 nm, then the orange to red higher & higher until you get into Infrared:

https://www.lasersafetyindustries.com/UV_Laser_Safety_Glasses_and_Goggles_s/73.htm
***

Then the issue of "blue blocker" glasses for general protection from the sun, to block a bit above 400nm. Traffic lights seem to be above around 450nm, so you don't want to block above that:
green LED 500 nm peak LAMP w/ colored lens 450-600
amber LED 585 nm peak LAMP has much more to right
red LED 657 nm peak LAMP has much more to right

https://archive.education.mrsec.wisc.edu/background/LED/traffic_light/spectra.htm
***

Then the issue of sunglasses that advertise "blocks 99.9% of UV" sometimes further specified as "UV-A and UV-B."
I don't know if the portion passed is on the low end or possibly the part above 385 nm.

I don't know if 385 nm to 400 nm is really a hazard, wrt sunshine or what might be re-emitted by what I shine the light upon.

Can someone link to the spectrum graph of the Nichia NCSU276A 365 LED ?

EDIT : spec sheet, graph on pg 11:

https://www.nichia.co.jp/specification/products/led/NCSU276A-E.pdf

lumen,
If you could let us know the results of your search for adequate UV protective goggles, it would be most appreciated. I have a pair of 365nm UV lights - mostly just to have them - and I have some clear polycarbonate protective glasses, but I don't feel very knowledgeable about whether or not they would do a good job of protecting eyes. There are very few people I would even consider loaning the UV lights to, but they would get the better-safe-than-sorry lecture first. Is it necessary to get welding goggles?

This is a bit like hearing safety threads in the gun forums. Some people laugh it off but cumulative damage is just that. It adds up! Take the time to take care. In order to help me and anyone else do that, does someone have a good explanation (or link) for the differences in UV exposure and risk we get from:

- the sun,

- those "black lights" people use at parties and "haunted houses",

- the bargain UV lights that shine in the upper 300nm range up through 400nm and into the violet or blue end of the visual spectrum,

- the higher quality 365nm UV lights that seem popular here?

Also, what are the most powerful UV flashlights on the market? I know the single-cell Convoy or the single-cell alkaline models from Jetbeam or Jaxman can be dangerous but doesn't somebody make a big UV thrower for bug/scorpion hunting or something?

FWIW, but not to diminish Any of the cautionary nature of this thread, it seems like UV blocking is a common feature of many contact lenses.

Honestly, some things just aren't worth messing around with. I have one UV pocket light. It has other modes besides UV. And comes with a special filter to reduce damage to eyes. But still.... I just don't mess around with UV. Best to leave some things alone.

365nm users, what glasses do you use for safety? I cant find a definitive answer or recommendation yet.

I have run a plasma arc gun for the past 31 years and have burned my eyes more times then then I can count. It ain't fun.

I think hard polycarbonate safety glasses in general block UV. Because I wasn't totally sure, I bought some that say so. (See link below.) To test them, I got two. I put one on. Then I used the other to interrupt the UV beam path on appropriate test materials. They seem to work just fine.

https://www.amazon.com/dp/B01AWK1XAS/?tag=cpf0b6-20

I used the Jaxman E3. It's supposed to be 365nm and has a filter to block emission in the visual spectrum. (I don't store it with a battery installed.)

I think one point of terminology that is potentially misleading is "UV blocking"

Most transparent materials may reduce by some percentage, and transmit some percentage, of the incident radiation.

The term "blocking" may (falsely) imply that there is no transmission, somewhat analogous to the (mis)use of the term "waterproof" (water-resistant)

So the more relevant safety issues really relate to the power of the source and whether any particular filter is adequate for the specific situation (duration, intensity, direction, reflection, etc, etc)

This is one reason why these "UV safety" threads here on CPF often devolve into over-generalization, which is unfortunate.

It is an important topic, but anyone using UV should exercise due diligence in understanding the safety issues, and in selecting and utilizing protective equipment appropriate to their own exact situation.

I don't look at UV lights, but the maker of my contact lenses claims that the lenses (Air Optix) block 90% of UVA and UVB.
I don't consider them to be serious protection from UV, but being less likely to develop cataracts is some consolation for needing corrective lenses.

- just saw that I already posted about this in July.