41. This is possible because the turbine exhaust gas ( flue gas ) still contains some oxygen. 42. Now the exhaust gas will contain more oxygen. 43. Closed-loop fuel injection systems improved the air fuel mixture control with an exhaust gas oxygen sensor. 44. In this application, a polyimide needle felt separates dust and particulate matter from the exhaust gas . 45. The exhaust gases escape through the same vent pipe used to supply air to the fire. 46. These analyzers are much more sensitive and much faster than a typical portable exhaust gas analyzer. 47. This negative pressure causes backdrafting ( the movement of exhaust gases back into the house ). 48. Windows in many homes have vents to open to protect the occupants from excessive exhaust gas . 49. The improved combustion results in reductions of diesel particulate matter as well as toxic exhaust gases . 50. As for emissions, a promising technology called exhaust gas circulation can be harnessed for reducing exhaust.
