The enforcement test tolerances (which are relevant only to the "downstream standards" which are oxygen, benzene, and RVP) would apply to samples of RFG collected subsequent to movement of the RFG from the tank in which the certification sampling is conducted, even when these subsequent samples are collected within the refinery or import facility where the gasoline is produced or imported. Thus, a refiner or importer may conduct a quality assurance program of the RFG located at the refinery or import facility that previously has been certified, and use the "downstream" enforcement test tolerances when evaluating the quality assurance samples.(12/5/94)

This question and answer was posted at Consolidated List of Reformulated Gasoline and Anti-Dumping Questions and Answers: July 1, 1994 through November 10, 1997 (PDF)(333 pp, 18.17 MB, EPA420-R-03-009, July 2003, About PDF)