<p>A system for cleaning air in a vehicle by ultraviolet light includes an exposure chamber for exposure of air to ultraviolet light. An ultraviolet light source is mounted in the exposure chamber. A collection plenum chamber is connected to a first end of the exposure chamber. An air valve is connected to the collection plenum chamber. An expansion plenum chamber is connected to a second end of the exposure chamber including passages for distribution of air to the exposure chamber. An inlet conduit connected to the expansion plenum chamber directs air to the expansion plenum chamber. The system reliably cleans air and may be packaged so as to be integrated into existing vehicle structures, such as a passenger service unit of an airplane.</p>
