FDA on Sunglasses..............................

[Chris Ryser]

FDA on Sunglasses

Choose sunglasses that are labelled with a UVA/UVB rating of100% to provide the most UV protection.

Do not mistake dark-tinted sunglasses ashaving more UV protection. The darkness of the lens does not indicate itsability to shield your eyes from UV rays. Many sunglasses with light-colourtints, such as green, amber, red, and gray offer the same UV protection as verydark lenses.

Children should also wear sunglasses thatindicate the UV protection level. Toy sunglasses may not have any UVprotection, so be sure to look for the UV protection label.

Large, wraparound-style frames may providemore efficient UV protection because they cover the entire eye-socket. This isespecially important when doing activities around or on water because much ofthe UV comes from light reflected off the water’s surface
.
Sunglasses are the most effective when wornwith a wide-brimmed hat and sunscreen.

• Use extra caution near water, snow, and sand because they reflect damaging UV rays and increase your chance of sunburn and other damage to the skin and eyes.

Comment: How testsunglasses for UV protection

Many opticians are using UV Meters to test if lensesabsorb all the UVA and UVB.


Warning:

However manyof these UV Meters have been made and sold to the optical retail industry, and indicatefull UV 100% absorption at 382 nm which is only 50% of the UVA range. They givea faulty reading.


Examples of Broad-Spectrum Ingredients

Ingredients	Other Names
Benzophenones	Oxybenzone
Cinnamates	Octinoxate Cinoxate
Ecamsule	Mexoryl SX
Sulisobenzone
Salicylates
Titanium Dioxide
Zinc Oxide
Avobenzone	Parsol 1789

http://www.fda.gov/Radiation-Emittin...116445.htm#top

[pseudonym]

Great post- we have to specify "UV" on any CR-39 in comments. They don't put it on automatically. But I don't have a UV meter to make sure the lab gets it on there. Considering the number of times the glasses have come through without AR, I really really wonder how many times the UV gets forgotten. Is there a way to tell if it's been done without a meter?

[Wes]

A cr-39 lens that's been uv treated will have a very faint greenish-yellowish hue to it. This is much easier to notice on the beveled areas and less obvious on the surfaces due to the porosity of the uncoated, freshly cut material.

[uncut]

Great post- we have to specify "UV" on any CR-39 in comments. They don't put it on automatically. But I don't have a UV meter to make sure the lab gets it on there. Considering the number of times the glasses have come through without AR, I really really wonder how many times the UV gets forgotten. Is there a way to tell if it's been done without a meter?

Yes! A old school, low tech method was to use fluorescing ink on paper, and using a intense UV light source, like a Burton Lamp, to view the ink print(symbol) through the magnifier. You could at least verify that the lens had some UV blocking capabilities, and was indeed treated.

[Wes]

Yes! A old school, low tech method was to use fluorescing ink on paper, and using a intense UV light source, like a Burton Lamp, to view the ink print(symbol) through the magnifier. You could at least verify that the lens had some UV blocking capabilities, and was indeed treated.

Nice!

[Chris Ryser]

As Wes stated a properly done UV treatment on a clear CR39 lens looks yellowish. However there are still plenty of opticians and optometrists that dislike that color and still use the clear UV treatments, if they do any, that go only to a 382nm absorbtion which is half way between the 360 and 400 nm.

Some of the dyes suppliers have been wrongly advertising the protection factor of clear UV as full UV which it is not. If a consumer does not like the yellowish tint, dip the lens into some blue and it will show barely, but you should not use or refuse to pass on any clear UV treated CR39 lenses as they are not up to standard. This has been going on for many years.

As to UV meters, there many on the market at very attractive prices and should be in every store just about as they were 20 years ago. Lately with the hype on AR coated lenses UV has been put on the back shelf. Maybe its time to bring back into fashion as it is really a health matter.
Polycarbontae is no problem as it contains all the protection needed but CR39 does need it. So do sunglasses of all sorts.

When the summer arrives and the new FDA rules will be in force there will be a lot more talk about UV protection. As professionals, opticians should be prepared for it.

[pseudonym]

Yes! A old school, low tech method was to use fluorescing ink on paper, and using a intense UV light source, like a Burton Lamp, to view the ink print(symbol) through the magnifier. You could at least verify that the lens had some UV blocking capabilities, and was indeed treated.

Can't get much more old school than a black light. Make a surface painted florescent directly across from the black light, then insert the lens in question between the light and the painted surface. If the UV coat is present, there will be little to no fluorescing through the lens. It won't tell the transmission, but it will show if there is some UV coat. Or am I just being too cheap to buy a UV meter?

[Chris Ryser]

Can't get much more old school than a black light. Make a surface painted florescent directly across from the black light, then insert the lens in question between the light and the painted surface. If the UV coat is present, there will be little to no fluorescing through the lens. It won't tell the transmission, but it will show if there is some UV coat. Or am I just being too cheap to buy a UV meter?

In todays age when one very probably has a cell phone in the pocket which shakes when an e-mail comes in and you can answer it, you should not be proud of you black light invention.

I developed one of the early exact measuring UV Meters in 1984 and we built and sold a many over a 15 year period until the photocells we used where discontinued by the japanese manufacturer. Today there is a wide choice available in various price ranges.

A UV meter is not only a testing instruments it is actually a superb aide in selling the lenses.

[Barry Santini]

Regardless of the new guidelines/rules or reawakening about UV, the following Ophthalmic Law of UV Protection will still be as valid tomorrow as it is today:

"The need for UV protection in non-sunglass wearers is inversely proportional to the degree of ammetropia"

It has always been this way. As an industry, we are either unbelievably illogical in how we formulate our safety recommendations, and/or..
the public is equally clueless.

If we were really consistent about the need to block UV, then we'd more rapidly embrace (and price) the cost of fashion frames with plano UV lenses.

Heh....now there's a funny thought: Crizal UV Plano lenses.

Funny, it almost makes sense for us to advocate 'reverse' (aka Bizarro) refractive surgery.

B

[pseudonym]

A UV meter is not only a testing instruments it is actually a superb aide in selling the lenses.

I'm thinking about it but right now, all I want is be sure the lab is putting the UV coat on. We have a running sunglass sale where the lens is free but it has to be plastic.

If my cell phone were that special, it would have a black light.

[pseudonym]

A cr-39 lens that's been uv treated will have a very faint greenish-yellowish hue to it. This is much easier to notice on the beveled areas and less obvious on the surfaces due to the porosity of the uncoated, freshly cut material.

I have an untreated blank someplace around here that can be used to compare- thanks for that info. It's the suns I'm really concerned about. We sell a lot of them and there's no way to check. (Yet.)

[uncut]

Perhaps you could ask the lab to record and verify the test results, and possibly supply you a "authenticity" certificate with each pair?

[Chris Ryser]

Perhaps you could ask the lab to record and verify the test results, and possibly supply you a "authenticity" certificate with each pair?

Authentic certificats could only be issued by the use of a real spectrometer which is a costly item to purchase, ............wonder if lab would install one if they don't have one.

[pseudonym]

The last two comments made me laugh. But the solution is simpler than I thought. We have one of those UV lights that checks transitions. I can just put a florescent strip under that to see how much glows behind the lens. Not a quantitative test, but it may ease my mind if I see that some coating is applied. Thanks for your help.

[Wes]

Keep in mind that CR-39 still blocks some UV, and the thicker it is, the more it blocks.

[pseudonym]

Keep in mind that CR-39 still blocks some UV, and the thicker it is, the more it blocks.

Thank you for that wrench. OK, I was planning to use a poly lens for comparison purposes. Say what you will about poly, it has its good points. If the plastic lens I'm checking fluoresces as much as the poly, is it safe to say the coating is there?

[Barry Santini]

Found this paper from June 2011 on the crizal site:

http://www.crizalusa.com/ECP-Resourc...le%20Paper.pdf

Interesting....

B

[Chris Ryser]

• Although a small amount of UV comes from
artificial sources, the overwhelming bulk of the
UV to which people are exposed comes from
the sun

• UV can cause health effects both through
direct damage to DNA and through photosensitizing
reactions that cause the production of
free radicals and oxidative damage

• The retina and other posterior ocular
structuresare protected from UV by the cornea and the
crystalline lens, which together absorb almost
all of the UV that enters the eye. This, however,
puts the protective structures at risk

• Although UV can be harmful, some UV exposure
is necessary for good health


It looks like the hype is on with a new wave and cycle of UV protection as it was in the 80's when UV meters were used by most opticians and UV protection was the big fashion. Most labs and opticians with finishing labs would do their own UV jobs.