This test method may be used to:

Determine the pore size distribution of a geotextile,

Determine the maximum pore size of a geotextile,

Determine the mean flow pore size of a geotextile,

Determine the effect of processes such as calendering or needle punching upon the pore size distribution,

Determine the effect of compression upon the pore size distribution of a geotextile, and

Determine the gas flow rate of a geotextile, and thereby its gas flow capability.

The pore size distribution test is significant not only for indicating pore sizes, but may also indicate a damaged, contaminated, or clogged geotextile.

1.1 This test method covers the determination of the pore size distribution of geotextile filters with pore sizes ranging from 1 to 500 μm.

Note 1—The accuracy of this procedure has been verified up to a maximum pore size of 200 μm. Above this value accuracy has been found to be equipment dependent and should be verified by the user through checks on materials with known opening sizes.

1.2 The test method measures the entire pore size distribution in terms of a surface analysis of specified pore sizes in a geotextile, defined in terms of the limiting diameters.

1.3 The analyst should be aware that adequate collaborative data for bias statements as required by Practice D 2777 is not provided. See the precision and bias section for details.

1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.5 This standard may involve hazardous materials, operations, and equipment. 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.