1.1''This test method covers the procedure for determining the in-plane transmissivity of geosynthetics under varying normal compressive stresses using a radial flow apparatus. The test is intended to be an index test used primarily for geotextiles, although other products composed of geotextiles and geotextile-type materials may be suitable for testing with this test method.

1.2''This test method is based on the assumption that the transmissivity of the geosynthetic is independent of orientation of the flow and is, therefore, limited to geosynthetics that have similar transmissivity in all directions and should not be used for materials with oriented flow behavior.

1.3''This test method has been developed specifically for geosynthetics that have transmissivity values on the order of or less than 2 '' 10^'''4 m²/s. Consider using Test Method D4716/D4716M for geosynthetics with transmissivity values higher than 2 '' 10^'''4 m²/s.

1.4''The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the standard.

1.5''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.

1.6''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.