The deuterium injection subsystem was one of the engineering systems of Federation starships. It was an integral component of the warp propulsion system. This subsystem connected the deuterium tank to the dilithium regulation chamber. In this subsystem, the deuterium injectors were located under the tank, and the deuterium was streamed through the deuterium stream coils. Unlike the antiproton injection subsystem, the deuterium injection subsystem lacked a spin reversal system or injection seals. Aboard Galaxy-class starships, this subsystem was located on Decks 30 to 35. The location of this subsystem was labeled in a schematic of the secondary hull of the USS Yamato in 2365. (TNG: "Contagion" , "Booby Trap" , okudagrams)