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Fuels Registration, Reporting, and Compliance Help

In the GC-MS test for aromatics, why must the calibration curves be forced through the origin? All mass spectrometers will show some noise at a zero concentration level.

See More Frequent Questions about Fuels Registration, Reporting, and Compliance Help.

Calibration curves are not required to be forced through the origins. The reference in the regulation is a suggested method.(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)

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Fuels Registration, Reporting, and Compliance Help

In the GC-MS test for aromatics, why must the calibration curves be forced through the origin? All mass spectrometers will show some noise at a zero concentration level.

Fuels and Fuel Additives Compliance