  The decay of common radioactive gases, such as radon, produces stable
isotopes by a sequence of daughter particles with varied half-lives. These
daughter particles are a significant source of gamma, neutron, and alpha
particle backgrounds that can mimic desired signals in dark matter and
neutrinoless double beta decay experiments. In the LUMINA Laboratory at
Southern Methodist University (SMU), studies of radon plate-out onto copper
samples are conducted using one of XIA's first five UltraLo 1800 alpha
counters. We present results from investigations into various mitigation
approaches. A custom-built copper holder (in either plastic or metal) has been
designed and produced to maximize the copper's exposure to 220Rn. The 220Rn
source is a collection of camping lantern mantles. We present the current
status of control and experimental methods for addressing radon exposure
levels.
