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This International Standard specifies the gas chromatographic (GC) method for the determination of saturated, olefinic and aromatic hydrocarbons in automotive motor gasoline. Additionally, the benzene content, oxygenate compounds and the total oxygen content can be determined. This method defines two procedures, A and B. Procedure A is applicable to automotive motor gasoline with a total volume fraction of aromatics of up to 50 %; a total volume fraction of olefins from about 1,5 % up to 30 %; a volume fraction of oxygenates, from 0,8 % up to 15 %; a total mass fraction of oxygen from about 1,5 % to about 3.7 %; and a volume fraction of benzene of up to 2 %. Although this test method can be used to determine higher-olefin contents of up to 50% (V/V), the precision for olefins was tested only in the range from about 1,5 % (V/V) to about 30% (V/V). Although specifically developed for the analysis of automotive motor gasoline that contains oxygenates, this test method can also be applied to other hydrocarbon streams having similar boiling ranges, such as naphthas and reformates. Procedure B describes the procedure for the analysis of oxygenated groups in (automotive) ethanol fuels containing an ethanol volume fraction between 50 % and 85 %. The gasoline is diluted with an oxygenate-free component to lower the ethanol content to a value below 20 % before the analysis by GC. NOTE 1 For the purposes of this document, the terms ?% (m/m)? and ?% (V/V)? are used to to represent respectively the mass fraction, µ, and the volume fraction, f. NOTE 2 For Procedure A, precision data have been established for the oxygenate compounds in automotive motor gasoline samples containing ethyl-tert-butyl ether (ETBE), methyl-tert-butyl ether (MTBE), tert-amyl-methyl ether (TAME), iso-propanol, iso-butanol, tert-butanol, methanol and ethanol. The derived precision data for methanol do not comply with the precision calculation as presented in this International Standard. Applicability of this International Standard has also been verified for the determination of n-propanol, acetone, and di-isopropyl ether (DIPE). However, no precision data have been determined for these compounds. For Procedure B the precision can be used for an ethanol fraction from about 50% (V/V) up to 85% (V/V), total ether fraction from about 0,5% (V/V) up to 11% (V/V) and a total C3 to C5 alcohol fraction from about 1% (V/V) up to 6% (V/V). Methanol can also be determined using this procedure, but no precision data was established. NOTE 3 While developing this test method, the final boiling point was limited to 215 °C. NOTE 4 An overlap between C9 and C10 aromatics can occur. However, the total is accurate. Isopropyl benzene is resolved from the C8 aromatics and is included with the other C9 aromatics.