An official website of the United States government.

This is not the current EPA website. To navigate to the current EPA website, please go to This website is historical material reflecting the EPA website as it existed on January 19, 2021. This website is no longer updated and links to external websites and some internal pages may not work. More information »

Fuels Registration, Reporting, and Compliance Help

It is a common practice for diesel fuel to be blended with kerosene to improve performance characteristics (particularly during cold weather), or other substances, such as used oil to dispose of waste products. Can such practices be continued under the 15

Under § 80.522, used motor oil, or used motor oil blended into diesel fuel, may only be used in the fuel system of model 2007 or later diesel motor vehicles if the vehicle or engine manufacturer has received a Certificate of Conformity under 40 CFR Part 86, that certification is explicitly based on emissions data, and the motor oil is added at a rate consistent with the Certificate of Conformity. Under § 80.525, kerosene that a kerosene blender adds (or intends to add) to 15 ppm sulfur diesel must meet the 15 ppm sulfur content standard, as indicated by product transfer documents or test results.

Question and Answer was originally posted at Questions and Answers on the Clean Diesel Fuel Rules (PDF)(135 pp, 888 K, EPA420-B-06-010, July 2006, About PDF)