1.1 This test method covers the determination of the total amount of olefins in blended motor gasolines and gasoline blending stocks by supercritical-fluid chromatography (SFC). Results are expressed in terms of mass % olefins. The application range is from 1 mass % to 25 mass % total olefins. 1.2 This test method can be used for analysis of commercial gasolines, including those containing varying levels of oxygenates, such as methyl tert/butyl ether (MTBE), diisopropyl ether (DIPE), methyl tert/amyl ether (TAME), and ethanol, without interference.