This document establishes a terminology for the air filtration industry and comprises terms and definitions only. This document is applicable to particulate matter and gas phase air filters and air cleaners used for the general ventilation of inhabited enclosed spaces. It is also applicable to air inlet filters for static or seaborne rotary machines and UV-C germicidal devices. It is not applicable to cabin filters for road vehicles or air inlet filters for mobile internal combustión engines for which separate arrangements exist. Dust separators for the purpose of air pollution control are also excluded.