Re: RE: Questions regarding Appendix B of 10CFR20

[LIPTONW@dteenergy.com]

I'd like to reference ICRP 30 Part 1, which has a methodology for performing
a 
particle size correction. 
 
Herman Cember gave a talk at a Midwest Chapter, HPS on the internal
dosimetry 
of plutonium.  The "conventional wisdom" is that a larger particle size 
results in a lower dose.  He showed that the opposite is true for Pu-239, 
since the ALI is based on nonstochastic effects on bone, and a larger
particle 
size results in faster lung clearance and more bone exposure.   
 
The opinions expressed are strictly mine. 
It's not about dose, it's about trust. 
 
Bill Lipton 
liptonw@dteenergy.com 
 
You wrote: 
 
>For inhalation doses, not only the chemical form, however, is important to 
>ultimate dose.  The particle size is also critical.  If the activity median 
>aerodynamic diameter (AMAD) is 1 micron the lung will receive the inhaled 
>material to a very significant extent.  If the AMAD is 20 microns (boulders 
>by comparison) most of the material will not get to the deep lung and will 
>quickly enter the GI track.  
 
... 
 
>Martin J. Brennan 
>SNL, Org. 7526
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