Sterilization of Spacecraft Equipment using a Plasma Afterglow Circulation Apparatus

Abstract

A new afterglow circulation apparatus using cold atmospheric Plasma (CAP) is presented as a useful alternative sterilization method for spacecraft equipment. The developed setup uses the plasma afterglow generated by surface micro-discharge (SMD) technology and allows the control of gasflow, humidity and treatment volume. With the new setup we evaluate appropriate CAP conditions for a maximal sporicidal effect and examine the inactivation efciency by increasing the treatment volume. The sporicidal effect of the apparatus is tested with bacterial endospores Bacillus atrophaeus. A Fourier Transformation Infrared Spectrometer (FTIR) is used to analyse the detailed composition of the afterglow plasma. The study provides an insight into the plasma chemistry and the influence of the prevalent humidity involved in the inactivation of microorganisms. These Investigations are necessary to test the scalability and application for sterilization of spacecraft equipment. We will give an overview on the status of the plasma decontamination project and present the frst results of the plasma-gascirculation apparatus funded by the Bavarian Ministry of Economics.