Abstract: An air treatment system for a vehicle or other habitable structure. The apparatus includes a supply of treating fluid, a pump and spray nozzle arrangement, and a control system. The spray nozzle discharges the treating liquid in an atomized condition within an air circulation conduit, and the control system insures that there is air flow taking place in the conduit before atomization begins and that air flow is still continuing after cessation of atomization. The sequences is insured by a logic control and the pump is actuated through a timer and relay arrangement. An automatic conditioned responsive mode of operation can also be provided.