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Fuels Registration, Reporting, and Compliance Help

Can refiners linearize the distillation curve between points or must refiners curve fit data on every sample? Is linear interpolation using a table of values considered calculating E200 and E300 "direct from the data"?

Refiners should use the most accurate means available to determine values for E200 and E300. If these parameters can be measured directly, such direct measured values should be used. If E200 and E300 must be converted from distillation data, nonlinear curve-fitting would be considered more accurate than linear interpolation since distillation curves are generally nonlinear, and therefore should be used.(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)