A method and apparatus for decontaminating substantially enclosed environments by using ultrasonic cavitation of a cleaning fluid to produce a low pressure, low air flow mist that can be activated by a nonthermal plasma actuator to create a cloud of activated hydroxyl species with the capacity to decontaminate articles, open surfaces or substantially enclosed spaces of pathogens, including bacteria, and other pathogenic microorganisms. An automated system and related non-transitory computer medium are also disclosed.