Disinfection of an ambulance using a compact atmospheric plasma device

The worldwide spread of the coronavirus SARS-CoV-2 has highlighted the need for fast and simple disinfection processes, amongst others for ambulance cars on site. To overcome current drawbacks regarding room disinfection, the use of cold atmospheric plasma in remote operation represents a promising alternative for the disinfection of larger volumes. In this study, a compact plasma system was evaluated regarding its disinfection efficiency inside an ambulance car.

The developed plasma device is based on a dielectric barrier discharge (DBD) and operates with ambient air as process gas. The humidified afterglow from the plasma nozzle was introduced into an ambulance car with a volume of approximately 10 m³ while Bacillus atrophaeus endospores, Staphylococcus aureus or Phi 6 bacteriophages dried on different surfaces (PET-films, glass slides or aluminum foil) were exposed to the reactive gas inside the ambulance vehicle at eight different positions. Reductions of spores by more than 4 orders of magnitude were found on all surfaces and positions within 2 h. Due to their higher susceptibility, Phi 6 bacteriophages and S. aureus counts were reduced by at least 4 orders of magnitude within 30 min on all surfaces.

The results show that different microorganisms dried on variable surfaces can be inactivated by several orders of magnitude inside an ambulance by plasma gas from of a compact DBD plasma nozzle.

Plasma gas generated on site by a DBD plasma nozzle proved to be highly efficient for the disinfection of the interior of an ambulance car. Compact plasma systems could be a viable alternative for the disinfection of vehicles or rooms.