Abstract: The present invention relates to a device and method for decontamination. The device and method can be used to eradicate airborne and surface organic molecules and microorganisms, including pathogens, bacteria, and imbedded odors either on surfaces or items. The device includes a means to generate vapor-phase hydrogen peroxide, purified ozone and hydrogen radicals using UV light which treats fluids in multi-chambers, with passive or active mixing of the fluids taking place, prior to release of the treated fluid onto the surfaces or items to be treated. The method includes use of the device noted in an enclosed space, operated at a specified temperature and relative humidity range, by an operator outside the enclosed space. The surfaces and items are placed within the enclosed space for treatment.