Heavy-Duty Diesel Emissions, Fifty Years: 1960–2010

Exhaust emissions from heavy-duty diesel engines have been legislated since the 1960’s and continue until 2010. Smoke emissions continue to be controlled but exhaust odor regulations were never promulgated. Gaseous emissions (oxides of nitrogen, carbon monoxide, hydrocarbons) were not regulated until 1973 and particulate matter first regulated in 1988. Emission regulations have been through several periods of cooperation between regulators and manufacturers but there have also been periods of conflict and lawsuits. The most recent issues are with the October 2002 requirements of the Consent Decrees signed by seven diesel engine manufacturers and USEPA/US DOJ/CARB. Also the 2007/2010 regulations are under review.