California’s state mandate required fuel retailers to begin selling ultra-low-sulfur diesel on Sept. 1, making it the first state to do so. The rest of the states will comply with the federal mandate to begin selling ULSD on Oct. 15.
ULSD, which contains only 15 parts-per-million of sulfur compared to the current 500 ppm, is estimated to reduce harmful nitrogen oxide gas emissions by 2.6 million tons per year. However, the conversion to ULSD has been blamed for fuel shortages in some states.
