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Renewable Fuel Standard Program

Guidance on Qualifying an Analytical Method for Determining the Cellulosic Converted Fraction of Corn Kernel Fiber

This document provides guidance on how to demonstrate that an analytical method for determining the cellulosic converted fraction of corn kernel fiber co-processed with starch at a traditional ethanol facility satisfies the applicable regulatory requirements. Public confidence in the volumes of cellulosic ethanol produced under the Renewable Fuel Standard (RFS) program is important to the integrity of the program.

Affected stakeholders have sought clarification regarding what EPA will accept with regard to methods for determining the cellulosic converted fraction. The intent of this guidance is to explain our interpretation of our regulatory requirements and to articulate clear criteria for the type of analysis and demonstrations that EPA believes would be an appropriate basis for registration under the program.

Guidance Document (PDF) (13 pp, 726 K, EPA-420-B-19-022, May 2019, About PDF)