( Automotive engineering : Fuels, oils, emissions, and other fluids )
The government has introduced a series of Clean Air Act rules related to nitrogen oxides.
Vehicles running on fuel cells produce virtually none of the pollutants associated
with gasoline engines, such as nitrogen oxides and the greenhouse gas carbon dioxide.
Ozone is produced when nitrogen oxides, pollutants in cars' industrial exhausts, react with products of hydrocarbons.
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