Spatial distribution of particles on air filter media

[Gary Masters <gmasters@csn.net>]

Is anyone aware of a reference that would discuss spatial particle
distributions across air sample filter media?  That is, when an
operational air sample is collected, will the collected particles be
distributed evenly across the filter media, or will the particles be
concentrated towards the center of the media?
 
Please respond directly versus to the list.


  *********************************************************************
  * Gary Masters                                 Phone (303) 966-3266 *
  * Radiological Engineering                       Fax (303) 966-8459 *
  * Rocky Flats Environmental Technology Site                         *
  * PO Box 464   Building T690A               e-mail gmasters@csn.net *
  * Golden, Colorado 80402-0464                                       *
  *********************************************************************