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 www.epa.gov. 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 This website is no longer updated and links to external websites and some internal pages may not work.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

The RIA method for aromatics and olefins doesn't result in agreement with finished gasoline, i.e., the sum of the blendstock parameters doesn't equal the finished gasoline value (>6% delta). Are alternative methods okay?