Air decontamination devices in one example include a filter directly exposed to ultraviolet ("UV") radiation on an upstream side and a downstream side. Ozone may be provided to permeate the filter, as well. Reflectors may be provided to reflect UV radiation emitted in a direction away from the filter, towards the filter. The filter may be a V-bank filter, for example. Air sampling ports and prefilters may be provided. The air decontamination units may be used to decontaminate the air after industrial and medical contaminations and terrorist biological, chemical and radiological attacks, for example. Mobile isolation units, and methods of decontaminating rooms, are disclosed, as well.