200 to 230

[JMUCKERHEIDE@delphi.com]

Hi Paul, others,

Interesting. Thanks. Do you, anyone, know what the basis is for this NCRP
reported uncertainty of converting the WLM to dose to the bronchial
epithelium?  Is this with or without the WLM measurement uncertainty? (Note
the previous point that you can not know the actual dose in case-control
studies.) 

vs the uncertainty of "going from there to an effective dose equivalent"? (Ie, 
is there a specific reported uncertainty in the dose equivalent conversion
factor?) 

Thanks.

Regards, Jim Muckerheide
muckerheide@mediaone.net
Radiation, Science, and Health
=========================

> Bernard Cohen wrote:
> 
> >        Many thanks. I had not realized that NCRP-93 was based on 1.0
> >pCi/L average exposure. I looked it up and it was based on 40 Bq/m3
> >(1.08 pCi/L). Since the correct value is 1.25 pCi/L, that means
> >that the average U.S. exposure is increased from 200 mrem/y to 230
> >mrem/y.
> >Does anyone disagree on that?
> 
> The NCRP notes that the calculation of the 200 mrem has an uncertainty
> of plus or minus 50% just based on the uncertainties of going from WLMs
> to a dose to the bronchial epithelium and going from there to an effective
> dose equivalent. Given the magnitude of this uncertainty alone,  is
> refining the 200 mrem upwards to 230 appropriate?
> 
> Paul Frame
> Professional training Programs
> ORISE
> framep@orau.gov