There are two different limits for NOx / NO2 in Europe:
1) 80 milligrams NOx per km that a diesel car or truck drives:
Euro 6 .
(In some cities you can't drive a diesel that emits more than that.)
I'm considering on buying an older car but I haven't decided if it should be gasoline or diesel powered.
I would like to choose a diesel, but I'm considering the negatives: