Automatic and vehicle-mounted, Ward Diesel NO SMOKE Filter Systems offer exhaust filtration on scene, in the station — anywhere you need it. Our NO SMOKE 2 System is specifically designed for units built after 2007, including vehicles with DEF, that emit higher levels of harmful gases. The system is constantly filtering harmful exhaust from the environment inside the fire station at cold starts, and while low idling on scene. The original NO SMOKE System, designed for apparatus with pre-2007 compliant engines, offers automatic, hands-free operation when exiting or returning to station. A manual override switch allows the system to be activated on-scene. NO SMOKE Gas is designed to oxidize and reduce emissions from gasoline powered engines.