Abstract: In one aspect of the invention, a plasma reactor is arranged to treat aerosol particulates in a fluid stream passing through the reactor. The plasma reactor includes a plasma chamber having a self-cleaning electrode. The self-cleaning electrode is configured to clean various residues from the electrode without need to open or otherwise service the unit. In another aspect, the invention comprises a carbon-based pre-filter arranged to filter in flowing air to reduce the amount of silicone-based contaminant in the air flow before the air reaches the ionization chamber.