[ RadSafe ] Thorium Alpha and Beta Ratios

[Redmond, Randy (RXQ)]

Looking for some "field" information from those of you who have worked with thorium metal.  I am not looking for calculations/laboratory conditions information.  I realize that the information I'm asking for can be highly variable due to alpha attenuation from grease, oil, dirt, etc.

What ratios of beta-gamma to alpha contamination (fixed and removable) have you experienced on equipment and area surfaces (not on the metal) where thorium metal has been processed and stored?

Thank you,

Randy Redmond
B&W Y-12