PARTICLE ANALYSIS PROGRAM
AT LAWRENCE RADIATION LABORATORY
ROBERT E. HEFT and JAMES S. KAHN
_ Lawrence Radiation Laboratory, Livermore, California
ABSTRACT
A program has been established for determining the distribution of
individual radionuclides in particulate radioactive material. Particulate samples collected at their point of origin and selected on the basis
of the degree to which they represent the true particle population are
separated into groups and analyzed on a totality basis. The overall
analytical program is described, and an example is given of the initial
information produced in a particle-group separation performed on a
filter sample from the Sedan shot.
INTRODUCTION
The Particle Analysis Program at the Lawrence Radiation Labo-
ratory (LRL) is concerned with characterizing particulate radioactive
material as a function of sedimentation rate. Particulate samples collected at their sources are separated in the laboratory into fractions
corresponding to discrete sedimentation-rate intervals. Each fraction
is then subjected to chemical, physical, and radioisotopic analyses to.
provide a complete inventory, according to particle class, of each radionuclide studied. In addition, chemical composition, size distribution,
density, and crystallographic character of the particles are determined
for each fraction. The data provided by this program are directly applicable to three main problem areas: fallout, particle formation, and
biological availability.
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