FW: Thorium Lenses (fwd)

[Bruce Busby <bbusby@umich.edu>]

Here is the Fwd thorium glass message:

----- cut & Fwd'd -----------

From: Lindsey, Gary
To: RadSafe
Subject: Thorium Lenses
Date: Thursday, August 31, 1995 2:50PM

Third and final try:

>From 10 CRF 40.13, throrium contained in finished optical lenses is 
considered an unimportant quantity provided each lens does not contain more 
than 30 percent by weight of throium.

To meet this exemption:
  1.  Does the throium have to be uniformly distributed through the lens?
  2.  Does this exemption apply to thorium coating on lenses?

Specific references would be appreciated.

****************************************************************************  
*******************************
Gary Lindsey
Radiation Safety Branch, Office of Environmental Management
88 ABW/EMB
5490 Pearson Road
Wright-Patterson AFB, Ohio  45433-5332
Email:  lindseg@wrigem.wpafb.af.mil
Telephone:  (513) 257-2010    FAX:  (513) 476-1534
****************************************************************************  
*******************************
Standard disclaimer applies.