Need help settling a difference of opinion. Do all safety glasses need to be made in poly? Or can they be made in plastic as long as the Ctr thickness is 3.0?
Need help settling a difference of opinion. Do all safety glasses need to be made in poly? Or can they be made in plastic as long as the Ctr thickness is 3.0?
They can be made of any material, even glass, provided they pass the drop ball test.
Thanks, Mike. This is what the Ophthalmic Dispensing book said. But I chose to be skeptical :)
Oddly enough, glass isn't allowed as a material in safety glasses in Canada. We're usually so lax compared to you guys down there.
Why on earth would you want to use anything but poly or trivex?
did you ever try to get a DD in split adds in poly or trivex?Originally Posted by globaljp
Superior optics, scratch resistance, and you know what they say about men with thick lenses.
I didn't attend the funeral, but I sent a nice letter saying I approved of it. Mark Twain
They are safety glasses. Who gives about slightly better clarity. Why would you risk anything? Safety glasses will scratch easier regardless of material (other then glass). If you want better clarity use trivex. If you need a DD (I'm assuming that you are referring to a top and bottom FT) I find it hard not to believe if the lab can do it in plastic they could also do it in Poly.
Last edited by globaljp; 10-07-2014 at 07:28 PM.
Yes a DD is a double D top and bottom. Glass will also scratch and please let me know where I can get a DD in poly
Last edited by CME4SPECS; 10-07-2014 at 07:28 PM.
Yes I see i didn't word that perfectly for you. Everything scratches. Heres a couple options for you in trivex. I can order them on vision web at least.
http://www.allentownoptical.com/wp-c...inished-rx.pdf in Trivex and Plastic.
I also see iCare labs has a DD in Trivex available. So does Hoya.
What's there to risk, you can beat glass lenses with a hammer, many people work in environments where poly and trivex don't dare tread. Try arguing with a Boeing engineer or a physicist about their durability. As consumers we want and expect choices. They will get it elsewhere.
I didn't attend the funeral, but I sent a nice letter saying I approved of it. Mark Twain
Get what where? Im sorry sir your super unique DD lens is only available in a few materials. Trivex freaking bends in half and doesn't break. So your DD lens is available in Glass, CR-39 and Trivex that I quickly found. All my point was its pretty silly nearly all of the time to use something other then Poly or Trivex for a safety glass. just because you can doesn't mean you should.
There are certain activities in which glass is required. For example Mike up above has made a decent living selling an array of glass safety lenses for the glass and metal working enthusiasts, and X-ray glasses for those who work involves imaging in the medical field. The spouse of a coworker is an auto body man. The solvents and dust that permeates the air while he works makes it difficult for anything other than glass to survive. He wears 1.60 when out and about, but glass when in the shop. There are many reasons why one might use glass instead of poly or trivex. Not all safety concerns are for impact resistance...
"Some believe in destiny, and some believe in fate. But I believe that happiness is something we create."-Something More by Sugarland
New timers. New jargon. 30 years dispense at least 20 cr safety glasses each and every week. Never had one to shatter.
http://www.laramyk.com/resources/edu...p-test-videos/
I completely understand that glass is very nice in certain circumstances. That is a tiny fraction of the people who need safety glasses. My dad welds, obviously his visor is not poly. Its glass.I have a mechanic whose glass lenses shattered when something broke and nearly lost his vision in one eye. He comes in once a year and gets a wiley x with poly lenses.
Last edited by globaljp; 10-07-2014 at 10:38 PM.
see all ======> http://www.ccohs.ca/oshanswers/preve...e/glasses.html
Canadian Centre for Occupational Health and Safety
www.ccohs.ca
Glass is about 10 times as scratch resistant than any other ophthalmic lens material.
The only reason glass is used in welders helmets is for the scratch resistant factor of it. Which that is a moot point when all the hot metal sparks are hitting the glass and burning right into it.
Not quite. Not even close, actually.
Glass is used because the colorants are actually part of the glass and not dyed in (which fades over time).
Additionally, a clear polycarbonate plate in front of the glass protects it from hot metal blobs.
Thanks for that info, the last time I checked with my supplier, they said I couldn't get that.
Thanks, This was very helpful.
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