Stable glow-type discharge plasmas at elevated pressures can be generated and maintained easily when the plasma is spatially confined to cavities with critical dimensions below 1 mm ('microplasmas'). We studied the properties of several atmospheric-pressure microplasmas and their use in the remediation of volatile organic compounds (VOCs) and biological decontamination. The VOCs studied include individual prototypcal aliphatic and aromatic compounds as well as mixtures such as BTEX (benzene, toluene, ethylbenzene and xylene). The biological systems under study included individual bacteria as well as bacterial biofilms, which are highly structured communities of bacteria that are very resistant to antibiotics, germicides, and other conventional forms of destruction.

Nonthermal plasma, which is produced at atmospheric temperature and pressure, generates sterilants that kill high concentrations of microorganisms and inactivate viruses during a 10-minute exposure. The primary injury appears to be at the surface structures of the organisms. This suggests that nonthermal plasma has utility for sterilization of heat-sensitive medical materials and devices.

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In atmospheric-pressure gas discharge system, slit discharge (SD), has been developed for the removing biological and chemical contaminants from the ambient air. The system consists of multiple plasma grids stacked perpendicularly to the air flow. . The performance of the system has been tested using the surrogates of biological and chemical warfare agents. The results of the biological testing will be presented. The experiments have been done using the "in-room" and "in-duct" scenarios, simulating the stand alone room air cleaner and the HVAC system. The efficacy of the system in removal of bacterial spores will be presented as a function of flow rate, discharge power, number of plasma grids, and concentration of the spores in the air. Sampling methods and associated challenges will be discussed.Slit discharge (SD) is a promising technology in air-cleaning. Its performance is comparable with and often exceeds that of the convectional methods, such as dilution ventilation, filtration and ultraviolet germicidal irradiation. SD is an energy efficient, high performance, and low cost technology for air decontamination with potential uses in industry, health care and household applications.