Re: Annular Kinetic Impactor

[Keith <WELCH@CEBAF.GOV>]

I had some experience with the impactor of which you speak.  As previously
mentioned the impactor separates by particle size.  Our efforts indicated that
in the field, you can assume that the dust, rust, or flying debris you are
concerned with (i.e.transuranic laden) is indeed large chunks compared to the
radon daughter particulates you are trying to avoid.  We did a bunch of
empirical tests during actual work on contaminated equipment undergoing surface
removal activities.  We used different adjustments on the inner orifice to
"outer" impactor surface distance and came up with a sampling/counting regime
that worked well.  We even presented our results at a midyear HPS meeting back
in 1988 (I think).  This is about all I can remember from that era.  If you
want nitty gritty ( which we generated plenty of), contact me and I can give
you names and telephone numbers of people who have all the data and still use
the devices to the best of my knowledge.

Keith Welch      welch@cebaf.gov
               804 249-7212