What are Nitrogen Oxides?
A group of compounds most commonly found in vehicle exhaust, where Nitrogen Oxides are a byproduct of combustion formed from the Nitrogen and Oxygen in the air. In exhaust, the most common is Nitric Oxide (NO) followed by Nitrogen Dioxide (NO2). Other Nitrogen Oxides found in much smaller quantities are N2O, N2O3, N2O4, N2O5, N3O4 AND NO3.