We don't recommend didymium lesnses for glassblowing (and I'm talking about furnace glassblowing not lab glassware lampwork which doesn't require as much eye protection) is that the spectra from the didymium glasses we've looked at shows they don't stop either near or far IR worth diddly. That's the significant radiation hazard from this work. NIOSH did a study some years ago of furnace glassblowing and came to a similar conclusion. (My MFA major was in ceramics and glassblowing.)
Monona
In a message dated 10/1/2010 2:26:00 PM Eastern Daylight Time, dakatz45**At_Symbol_Here**MSN.COM writes: The main reason welders wear dark lenses is so that they can see the bead of material as they weld. Although the lenses are designed to filter any UV or IR. It's similar to wearing didymium lenses for glassblowing.
Also, wearing goggles when trying to view visible light spectra through one of those small school spectroscopes makes it very difficult to see the spectra through the small opening in the spectroscope. This is not one of those old carbon arc spectrographs that I learned on in my undergraduate days.
David
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David A. Katz
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