What is the Sulfur content of low sulfur diesel Fuel? (LSD)
Before 1993, the allowable sulfur level in diesel fuel was 5,000 parts per million (ppm). From 1993 until 2006, the allowable sulfur was 500 ppm.
Low sulfur diesel (LSD) was replaced with ultra-low sulfur diesel (ULSD) in 2006 as part of an initiative to substantially lower the emissions of particulate matter in diesel engines. The initiative began in the European Union and later expanded to the United States.