Ultra-low Sulfur Diesel (ULSD)

Ultra-low Sulfur Diesel (ULSD)

A diesel fuel with 15 parts per million (ppm) or lower sulfur content. This ultra-low sulfur content enables use of advanced emission control technologies on light-duty and heavy-duty diesel vehicles. Most highway diesel fuel refined in or imported into the United States is required to be ULSD. One hundred percent must be ULSD nationwide by 2010.

Ultra-low Sulfur Diesel (ULSD)