----- Original Message -----

From: DAVID KATZ

To: DCHAS-L**At_Symbol_Here**LIST.UVM.EDU

Sent: Friday, October 01, 2010 11:21 AM

Subject: Re: [DCHAS-L] UV protection & spectra tubes

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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----- Original Message -----

From: Ray Mainer

To: DCHAS-L**At_Symbol_Here**LIST.UVM.EDU

Sent: Friday, October 01, 2010 7:26 AM

Subject: [DCHAS-L] UV protection & spectra tubes

  All,

Several years ago, I put several types of lenses (safety glasses,
goggles, and my eye glasses) in our UV-Vis spectrophotometer to see how
well they absorbed UV.   The results I got showed high UV absorption and
were consistent with the manufactures' claims for UV absorption.   The
exact results are lost in time somewhere.

The glass of the gas discharge tubes (If they are glass.) should absorb
much of the UV too.  Thats why UV cuvettes are made out of quartz.  
Could anybody check with a UV meter?

We can't weld with clear glassees because the visible and IR would also
damage the eyes.

Ray Mainer