This test method provides measurement of total sulfur in automotive fuels with a minimum of sample preparation. A typical analysis time is 200 to 300 s per sample.

The quality of automotive fuel can be related to the amount of sulfur present. Knowledge of sulfur concentration is necessary for processing purposes. There are also regulations promulgated in federal, state, and local agencies that restrict the amount of sulfur present in some fuel.

If this test method is applied to petroleum materials with matrices significantly different from the calibration materials specified in this test method, the cautions and recommendations in Section 6 should be observed when interpreting the results.

1.1 This test method specifies an energy-dispersive X-ray fluorescence (EDXRF) method for the determination of total sulfur in automotive fuels with a concentration range of 6 mg/kg to 50 mg/kg.

1.1.1 The pooled limit of quantitation of this test method as obtained by statistical analysis of inter laboratory test results is 6 mg/kg sulfur.

1.2 A fundamental assumption in this test method is that the standard and sample matrix is well matched. Matrix mismatch can be caused by C/H ratio differences between samples and standards or by the presence of other heteroatoms.

1.3 The values stated in SI units are to be regarded as the standard. The preferred concentration units are mg/kg sulfur.

1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.