Atlantic Utraviolet Corporation SaniTaire Room Air Sanitizer features polished interior chamber for providing a highly reflective surface to maximize ultraviolet intensity within the chamber, elapsed time indicator to provide realtime, non-resettable display of accumulated operating hours, louvered exhaust panel that protects the occupants in the room from ultraviolet exposure by restricting ultraviolet radiation from passing into the room, lamp operation indicators to provide positive indication of germicidal lamp operation, and differential air pressure gauge used to measure filter resistance by measureing the pressure difference between ouside air and the pressure in the blower compartment.