The present invention provides an air treatment unit including a module power socket; an air treatment duct having an interior defining an air path; and an ultraviolet light module that selectively engages the air treatment duct, the ultraviolet light module including a housing having a baffle; an integral ultraviolet light source and light source socket, the ultraviolet light source being fixed to and extending through the baffle; and a connector that selectively mates with the module power socket, the connector being in power transmissive communication with the light source socket, wherein, when the ultraviolet light module selectively engages the air treatment duct and the connector selectively mates with the module power socket, the ultraviolet light module cannot be fully removed from its engagement with the air treatment duct without disconnecting the power.