Measurement of hot-particle dose profiles using exoelectron dosimeters

Since 1985, staff at Battelle's Pacific Northwest Laboratories (PNL) have analyzed hot-particle contaminants and assisted in the evaluation of hot-particle exposure events at nuclear power plants. More recently, staff have performed an assessment of the thresholds for nonstochastic skin effects caused by hot particles of different sizes and beta energies. The purpose of this paper is to describe methods used for measuring hot-particle dose rates and methods for characterizing dose profiles from particles. The use of exoelectron dosimeters to quantify depth and lateral dose profiles represents a significant improvement in the characterization of radioactive sources, especially for hot particles. Researchers would like to develop a definitive model to relate the dose profiles from hot particles to the induction of nonstochastic skin effects. This objective is now made possible through development of an accurate measurement technique to confirm theoretical calculations. Exoelectron dosimeters can be used to perform such measurements as well as dose rate measurements to 1 cm{sup 2} of skin for regulatory purposes.