Hi Grace and Tom.
The electromagnetic radiation we expose ourselves to in the shop
affects three different tissues in the eye and varies with the
portion of the spectrum under consideration. The tissues are the
cornea, the lens and the retina; and the spectral segments infrared
(heat), visable light and ultraviolet.
Heat is absorbed partially by the cornea but very strongly by the
surface layers of the lens, causing a very specific type of
cataract. For that reason lampworking bead makers should wear
infrared absorbing goggles as, you can be assured, Dale Chuhuly and
his workers do.
The visible portion of the spectrum passes through the cornea and
lens with little interruption unless we have cataracts. However the
retina, which absorbs the light in the process of seeing, can be
damaged by the light itself. The energy content is greatest in the
short (blue) wavelengths and the damage is directly proportional to
the intensity and exposure time. Consequently the retina has little
risk from the red-orange light of heat treating and silver/gold
soldering but great risk from the intense blue-white light of
platinum soldering, founding and welding. Real welding protection is
essential for platinum work while a lesser filtration is optional for
Ultraviolet light is strongly absorbed by the cornea where it can
easily cause a sunburn, as in the typical welders “flash burn”.
There is also some evidence that UV exposure accelerates the
development of cataracts.
Electric welding is a double whammy; not only is there UV to protect
yourself from, but the high intensity blue-white light can directly
burn the retina. UV protection needs to be wrap-around style–if the
arc can see your cornea it can burn it, you don’t have to be looking
at it. The retinal burn can happen in a flash (so to speak) and if
you happen to be looking at the source itself your central vision is
in bad trouble. I’ve seen electricians with permanent macular burns
when they inadvertently caused a big spark while “just doing their
So the message is: if you’re working with a major source of
infrared–filter; if you’re working with white hot materials and
techniques–filter; and if you’re heat-treating your tools or
soldering silver and gold filtration is optional so do what is
comfortable to you.