What is the permissible limit of nitrogen oxides for light-duty gasoline vehicles?

The permissible limit of nitrogen oxides for light-duty gasoline vehicles is set at 0.5 grams per mile (g/mi). This standard is established to help reduce air pollution and its harmful effects on public health and the environment. Nitrogen oxides (NOx) are significant contributors to the formation of ground-level ozone and smog, which can cause respiratory issues and other health problems. By limiting the emissions of NOx from vehicles, regulatory agencies aim to enhance air quality and protect ecosystem health.

Setting the limit at 0.5 g/mi balances the need for vehicle performance with the necessity to minimize environmental impact. This regulation reflects advancements in automotive technology that allow for lower emissions while maintaining vehicle efficiency and functionality.