ASTM D 7621 : 2016 : R2021

1.1This test method covers procedures (A and B) for the determination of the hydrogen sulfide (H₂S) content of fuel oils such as marine residual fuels and blend stocks, with viscosity up to 3000 mm²s^-1 at 50 °C, and marine distillate fuels, as measured in the liquid phase.

1.2Procedure A has been shown to eliminate interferences such as thiols (mercaptans) and alkyl sulfides. Procedure B can give elevated results if such interferences are present (see Annex A2).

1.3Valid ranges for the precision are given in Table 2 and Table 3. Measurements can be made outside these ranges however precision has not been determined.

1.4Samples containing FAME do not affect the measurement of hydrogen sulfide by this test method.

1.5The values stated in SI units are to be regarded as standard. Non-SI units given in parentheses are for information only.

1.6This 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.7This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.