Integrated Point Kernal Shielding Code
The program includes a newly written point-kernal shielding program (WinShield) based on the original models used in ISOSHLD. ISOSHLD also was used as the basis for Microshield ä available through Grove Engineering . Comparisons between the two programs over a range of container types and sizes showed very close convergence (± 5%) with material densities ranging from 0.2 g/cc to 1.2 g/cc. The program automatically predicts dose to activity conversion factors given an isotopic distribution and average dose rate.
(The slightly lower dose rates predicted by WinShield places the dose to curie conversion slightly more conservative than if the calculation were performed using Microshield.)
The figure above summarizes the comparisons run between WinShield and Microshield. In nearly all of the calculations the two codes were within 5% of on another. A little more variance is seen with the largest containers. In general it is difficult to predict dose rates with more accuracy. The variations imposed by using ICRP versus and ANSI dose conversion factors introduces more than 5% variation.
The differences between the two programs are somewhat amplified by the above figure. In the figure below, the actual dose rates calculated for one container size are compared. On this scale the Winshield results are basically indistinguishable from Microshield.
