Ethanol-blended gasoline must conform to ASTM D4814, E85 must conform to ASTM D4806, and biodiesel-blended fuel containing at least 6%, but no more than 20%, biodiesel must conform to ASTM D7467. Biodiesel blended fuel containing more than 20% biodiesel must conform to standards set by the Iowa Department of Agriculture and Land Stewardship. Additionally, biobutanol must be an agriculturally derived isobutyl alcohol that meets ASTM D7862 for butanol for blending with gasoline for use as a motor fuel. Gasoline blended with biobutanol must conform to ASTM D4814. The state defers to the U.S. Environmental Protection Agency for potential changes in specifications.
(Reference Iowa Code 214A.2 and Iowa House File 2128, 2022)