This year trains and ships will be smelling much better thanks to cleaner burning diesel. Starting tomorrow refiners must reduce the amount of sulfur in diesel fuel by 83 percent, and by 2010 the same low-sulfur requirements from autos will apply.

Refineries must reduce sulfur from 3,000 parts per million for non-road diesel fuel to a maximum of 500 ppm. So soon passengers getting on and off trains won't have to worry about "locomotive breath." Trains are more sustainable than cars in moving people or freight, and we need to address the serious under utilization of our railways.

In the U.K., Virgin Trains is testing biodiesel in some of its engines as part of Richard Branson's plan to green his companies. Kudos to the EPA for passing this regulation in 2004 and making diesel transportation more sustainable. Perhaps more people will be agreeable to ride trains when they lose their distinctive sulfuric smell.