5.1 This test method is intended for use in the laboratory or field in evaluating distillate fuel cleanliness.

5.2 A change in filtration performance after storage, pretreatment, or commingling can be indicative of changes in fuel condition.

5.3 Relative filterability of fuels may vary depending on filter porosity and structure and may not always correlate with results from this test method.

5.4 Causes of poor filterability in industrial/refinery filters include fuel degradation products, contaminants picked up during storage or transfer, incompatibility of commingled fuels, or interaction of the fuel with the filter media. Any of these could correlate with orifice or filter system plugging, or both.

1.1 This test method covers a procedure for determining the filterability of distillate fuel oils within the viscosity range from 1.70 mm²/s to 6.20 mm²/s (cSt) at 40 °C.

Note 1: ASTM specification fuels falling within the scope of this test method are Specification D396 Grade No. 2, Specification D975 Grade No. 2-D, and Specification D2880 Grade No. 2-GT.

Note 2: The test method has been used with lower viscosity middle distillate fuels such as Specification D396 Grade No. 1, Specification D975 Grade No. 1-D, and Specification D2880 Grade No. 1-GT, but the precision has not been studied and therefore the stated precision has not been validated for these grades.

1.2 This test method is not applicable to fuels that contain undissolved water.

1.3 The values stated in SI units are to be regarded as standard.

1.3.1 Non-SI units, specifically U.S. customary units such as temperature in degrees Fahrenheit and pressure in pounds per square inch gauge (psig), are included for information.

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

1.5 This 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.