How are UVC lamps used to disinfect the air?
Germicidal UVC lamps can be used in ceiling fixtures suspended above the people in a room, or within air ducts of re-circulating systems. The first method is called Upper Air Irradiation. The fixtures are shielded on the bottom so that the radiation is directed only up toward the ceiling and out the sides. These upper-air germicidal fixtures are mounted at least 7ft. above the floor so that people will not bump into them or look directly at the lamps. The second method of air disinfection uses UVC lamps placed inside the ventilation system ducts. If a ceiling is too low for an upper-air irradiation fixture, this type of an in-duct germicidal fixture can be used. Also, because people are not exposed to the UVC radiation, very high levels can be used inside the ducts. …
