A haƙiƙa, sauye-sauyen ƙarancin nitrogen ɗin tukunyar jirgi shine fasahar sake zagayowar iskar gas, wacce fasaha ce don rage iskar nitrogen ta hanyar sake shigar da wani ɓangaren hayaƙin tukunyar jirgi a cikin tanderun da kuma haɗa shi da iskar gas da iska don konewa. Yin amfani da fasahar recirculation na hayaƙin hayaki, zafin konewa a cikin babban yankin tukunyar jirgi ya ragu, kuma yawan adadin iska ya kasance baya canzawa. Ana danne samuwar nitrogen oxides ba tare da rage ingancin tukunyar jirgi ba, kuma an cimma manufar rage iskar nitrogen oxide.
Domin a gwada ko iskar nitrogen oxide na masu samar da tururi mai karancin nitrogen zai iya cika ka'idojin fitar da iska, mun gudanar da sa ido kan fitar da hayaki a kasuwa, kuma mun gano cewa masana'antun da yawa suna amfani da taken karancin nitrogen tururi don yin magudi ta hanyar farashi mai rahusa.
An fahimci cewa, ga masu samar da injin tururi maras ƙarancin nitrogen na yau da kullun, ana shigo da na'urorin daga ƙasashen waje, kuma farashin kona ɗaya ya kai dubun yuan. Ana tunatar da masu amfani da kada a jarabce su da ƙarancin farashi lokacin sayayya! Bugu da ƙari, bincika bayanan iskar nitrogen oxides.