Re: Respirable Particles - Pu and Cassini

["William G. Nabor" <wgnabor@uci.edu>]

Data on micron size is published:  Yeh, H.C., _et al_ "The proposed NCRP
respiratory Tract Model", _First Symposium on Pollution & Health Effects of
Aerosols_, Taiwan, September 10-12, 1991, pp 44-52.  I do not know the
relationship with filters.  Since clearance from the lungs requires that air
flow both ways, in and then out again, it is hard to see an obvious
relationship to filters with a one-way pump.

In Message Thu, 9 Oct 97 13:41:46 -0500,
  mcnaught@lanl.gov (Mike McNaughton) writes:

>>Particles that are too small act much as
>>gasses and are exhaled with the next breath (less than 10% of
>>spherical particles of unit density smaller than .01 microns will be
>>deposited in the lungs, with this fraction dropping to 0 at about
>>0.005 microns
>
>This is interesting. Is this published and/or documented?
>
>The standard textbook graphs of HEPA filter efficiency do not extend to
>particles this small. It would seem to follow, logically, that if it does
>not stick on the lung surfaces, presumably it does not stick on a filter
>either. How efficient are HEPA filters for nanometer sized particles?
>
>"Shlala gashle" (Zulu greeting, meaning "Stay safe")
>mike (mcnaught@LANL.GOV)
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William G. Nabor
University of California, Irvine
EH&S Office
Irvine, CA,  92697-2725
WGNABOR@UCI.EDU
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