[ RadSafe ] Dosimetry data for natural uranium

[David Cole]

Hi,

I am a long time lurker, this is my first post.

I do some work with natural uranium ore:  this is ore right 
out of the ground such as may be found at a uranium mine.

Any time I need to do any dose estimates (either external 
radiation or inhalation / ingestion) I go back to 'first 
principles' and calculate the appropriate factor (e.g. dose 
conversion factor or specific gamma dose constant) by 
assuming the presence of U-235, U-238 and Th-232 (in some 
assumed ratios) with all progeny in equilibrium.

This is a little bit labour intensive and possibly subject 
to error.

Is anyone aware of documented dosimetry data for natural 
uranium ore that can be referenced?

Note that this is for field work where approximations are 
acceptable and the calculations are used for estimates or 
screening hence tend to be conservative.

Thanks,

David Cole
Ottawa, Canada