The present invention provides for a system for disinfecting air circulated in an HVAC system. The system includes at least one spray ring forming a continuous loop surrounding an outer surface of HVAC ductwork. The system further includes a plurality of spray nozzles connecting to each of the spray rings in the at least one spray ring, wherein each nozzle extends through an aperture in the HVAC ductwork, wherein a space between each nozzle and each aperture is sealed by a rubber gasket.