ASTM D6426-07 - 1.7.2007
 
Significance and Use

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

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

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

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. Scope

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

Note 1

ASTM specification fuels falling within the scope of this test method are Specification D 396 Grade Nos. 1 and 2, Specification D 975 Grades 1-D, low sulfur 1-D, 2-D, and low sulfur 2-D, and Specification D 2880 Grade Nos. 1-GT and 2-GT.

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 the standard. The values given in parentheses are for information only.

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.

 
2. Referenced Documents

D4860-22

Standard Test Method for Free Water and Particulate Contamination in Middle Distillate Fuels (Clear and Bright Numerical Rating)

D2880-23

Standard Specification for Gas Turbine Fuel Oils

D2PP, Version 4.43, Determination of Precision and Bias Data for Use in Test Methods for Petroleum Products Available from ASTM International Headquarters. Order Adjunct No. .

D4177-22e1

Standard Practice for Automatic Sampling of Petroleum and Petroleum Products (Includes all amendments and changes 3/24/2023).

D975-26c

Standard Specification for Diesel Fuel (Includes all amendments and changes 7/20/2026).

D396-26a

Standard Specification for Fuel Oils (Includes all amendments and changes 4/14/2026).

D4057-22

Standard Practice for Manual Sampling of Petroleum and Petroleum Products

D4176-22e1

Standard Test Method for Free Water and Particulate Contamination in Distillate Fuels (Visual Inspection Procedures) (Includes all amendments and changes 6/30/2025).