Abstract: A system for treating air includes a first vent and second vent and an air passage in fluid communication between the first and second vents. Air is drawn into the first vent, moved through the air passage, and expelled from the second vent. The air passage includes an ultraviolet-C (“UV-C”) chamber, comprising a UV-C source, and a filter located after the UV-C chamber in the air passage and exposed to the UV-C source. Air moved through the air passage is treated by the UV-C source and then the filter. Such system may be used to treat air containing coronavirus particles.