Findings. The key findings of this study are as follows:
1. Attic dust collected from your residence contains enriched uranium, defined herein as material exhibiting a 235U/238U ratio that systematically exceeds the natural value of 0.00725. Five independent preparations of your attic dust resulted in a composite value of 235U/238U = 0.0120+/- 0.0005 (one standard deviation). The 234 U/238U atom ratio was also found to be elevated, with a composite value for the n=5 preparations of 0.000091 +/- 0.000004, which is also consistent with the presence of enriched U; in contrast, naturally occurring U has a 234 U/238U atom ratio of approximately 0.000055.