About EPA

Reduced Sulfur Content in Diesel Fuel

by Carol M. Browner
[EPA speech - May 17, 2000]

Today the Clinton-Gore Administration is proposing to dramatically reduce, by 97 percent, the amount of sulfur presently in diesel fuel in order to create the cleanest running heavy-duty trucks and buses in history.

This action will provide greatly improved air quality for all Americans. It will reduce smog-causing nitrogen oxides from these vehicles by 95 percent. It will reduce harmful particulate matter, or soot, by 90 percent. It is the clean air equivalent of removing from the air, the pollution generated by 13 million of today's trucks.

Every American who has driven behind buses or heavy-duty trucks is very familiar with the smell of diesel fuel and the clouds of thick exhaust emissions. Such air pollution is not just dirty and annoying -- it is a threat to our health, as there is growing evidence linking it to lung cancer. Soot and smog pollution are scientifically associated with 15,000 deaths annually, and a million cases of respiratory problems each year. They are also responsible for some 400,000 cases of asthma attacks every year, including thousands of aggravated cases of asthma, especially in children.

Last year, you may recall, President Clinton announced the toughest tailpipe standards ever for passenger cars, minivans, sport utility vehicles, and pick-up trucks. To achieve that goal in effective and affordable ways, we treated clean fuels and clean vehicles as a single system for the first time. Today, we are taking the same approach with regard to diesel fuel and heavy trucks and buses.

Today's action would reduce the sulfur content in diesel fuel by 97 percent. This means that for the first time ever, heavy-duty trucks and buses would be able to use pollution-control devices to meet emission standards, just as passenger cars have been doing for the last 25 years. These devices are sensitive to sulfur and will not work unless the amount of sulfur in the fuel is dramatically reduced.

That is why today's action is good news for everyone who wants to breathe healthier air, and especially good news for children, for senior Americans, and for people with existing respiratory problems. The fact is that an older, dirtier diesel vehicle can emit almost eight tons of air pollution per year. By reducing sulfur content in diesel fuel and requiring new engine standards, we would produce for the first time a fleet of dramatically cleaner heavy trucks and buses in America.

Specifically, adopting this proposal will mean that over 100 million Americans now living in areas that have difficulty meeting clean-air standards will be able to breathe healthier air in the future.

In the past, engine manufacturers have been able to meet permissive emission standards without the aid of control devices. However, the stringent standards in this proposal will result in the first broad use of emission control devices such as three-way catalysts and soot traps on these engines. These devices will allow manufacturers to produce engines that are dramatically cleaner than those on the road today.

This proposal allows adequate lead time and flexibility for industry to meet the new standards. The current level for sulfur in diesel fuel of 500 parts per million would be reduced to 15 parts per million by June of 2006. New trucks and buses would be required to meet standards progressively beginning in 2007 with full compliance by 2010. This will assure that the transition to cleaner vehicles can be accomplished cost effectively and without any disruptions. We are also taking comment on ways to provide additional flexibility for small oil refiners.

Americans want and deserve cleaner air. This action marks the Clinton-Gore Administration's latest step to provide it -- and to provide it cost-effectively. We are committed to finalizing this proposal within this Administration. It is part of an overall strategy that also includes cleaner fuels, cleaner passenger cars, cleaner SUV's, cleaner pick-up trucks, and cleaner coal-fired power plants. Together, these actions will ensure an unprecedented level of public-health protection for our communities and for our children as we begin the 21st Century.