Road transportation nitrogen oxides emissions in the U.S. 1970-2023
Road vehicles in the United States emitted 1.7 million tons of nitrogen oxides (NOx) in 2023. Emissions of NOx from road vehicles in the North American country have fallen considerably since the Clean Air Act was passed in 1970. Since then, increasingly stringent standards have resulted in NOx emissions from road vehicles to fall more than 85 percent relative to 2002 levels.
Heavy-duty trucks are a major source of transportation emissions in the United States. In November 2020, the EPA announced the launch of the Clean Trucks Initiative in a bid to decrease NOx emissions from HDVs.
Heavy-duty trucks are a major source of transportation emissions in the United States. In November 2020, the EPA announced the launch of the Clean Trucks Initiative in a bid to decrease NOx emissions from HDVs.
