California Starts The ULSD Era

Posted on September 1, 2006

As it typically does, California begins mandating the use of ultra-low sulfur diesel fuel today, six weeks ahead of the rest of the nation. Thus begins the ULSD era.

The fuel, required nationwide by October 15 for on-highway uses has 15 ppm of sulfur, a reduction from 150 ppm in California and 500 ppm for the rest of the U.S. A key to ULSD is that it “enables” the use of more sophisticated aftertreatment devices, a must as the on-highway diesel world enacts its new exhaust regulations January 1, 2007.

The Environmental Protection Agency required refineries nationwide to begin switching 80% of their diesel production to the ultra-low sulfur variety June 1.

California, as it typically does, requires the use of ULSD diesel today for all on-road and off-road diesel engines, except locomotives and marine equipment. Off-road diesels won't be required to use ULSD nationwide until 2010.