WarmGlass.com

I was asked during my class at WGW about infrared radiation eye protection for kiln workers. I originally said that didymium was adequate. Marty Kremer point out that this was incorrect (is there anything this guy does NOT know?), so I did some more research on this topic:

The infrared (IR) spectrum wavelengths ranges from 750 nanometers (nm) to about 10,000 nm. Any hot body emits infrared radiation. IR does not penetrate below the superficial layers of the skin. Radiation in the near infrared region (IR-A 750 nm – 1500 nm) can cause acute skin burn. The shorter wave lengths are also absorbed in the iris and cornea of the eye, from which heat is transferred to the lens. Excessive exposure of the eyes to infrared radiation from furnaces and other hot bodies had traditionally been thought to produce “Glass Blower’s Cataractâ€

Greg,

A couple of other points to make:

Quartz and fused silica windows, the type found in modern kiln windows, pass infrared energy out to 5 microns, or the mid-infrared wavelengths... staring at your fused glass through these windows does not protect your eyes from infrared radiation, so cataracts due to the long term exposure of infrared energy is still a potential problem. IR1.7 and 2.0 welding lenses block 95% of infrared energy and the IR3 welding lenses block close to 98% of the infrared energy, but the tradeoff is visibility under white light conditions. Shortwave UV light, such as the radiation emitted by lamps used to detect the tin side of float glass, also causes cataracts after long term exposure and is also considered a cancer causing agent for skin exposure.

Tony

Greg- for what it's worth, I just had a cataract removed and a plastic lens put in. An elegant operation. I'm told that I'm young (55) for this, and that all the causes are not known, but steroid use and excessive exposure to sunlight are a couple. I did a couple of years of glass blowing about 10 years ago and had welders' glasses most of the time. Who knows?
Anyway, the new bionic lens is interesting- a slight vision correction and a significant (for me) color shift, so I see cooler colors better with the new lens, and warmer colors with the other. My doctor is intrigued and is betting that the brain will compensate; no one's mentioned this to him before.

I can't take credit for the knowledge, btw, just for being in the room and paying attention when Monona "Doom-and-Gloom" Rossol gave her talk on safety at BeCon this summer.

Marty