The regulations do not define computer-controlled in-line blending. Generally, EPA will consider an in-line blending operation to be adequate if it has sophisticated computer monitoring and recording of all relevant data generated during the batch.
These systems would also include computer control and adjustment of the blend properties during production depending on other parameters. In-line blending systems vary with regard to degree of automation. As a result, the sufficiency of any particular system will have to be evaluated on a case-by-case basis.(7/1/94)
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)