Washington Revised Code Title 43. State Government--Executive § 43.19.643. Biodiesel fuel blends--Definitions

(1) “Biodiesel” means a mono alkyl ester of long chain fatty acids derived from vegetable oils or animal fats for use in compression-ignition engines and that meets the requirements of the American society of testing and materials specification D 6751 in effect as of January 1, 2003.

(2) “Ultra-low sulfur diesel” means petroleum diesel in which the sulfur content is not more than thirty parts per million.