Equivalence of Air and Water Permeability Tests in Evaluating Engineering Fabrics

Permeability characteristics of civil engineering filter fabrics are currently evaluated by three types of tests: air permeability and falling-head and constant-head water permeability. Test procedures for the falling-head and constant-head water permeability tests are discussed, and results from these tests are correlated to air permeability results for filter fabrics. Several commercially available filter media were tested by these methods and a high degree of linearity between the tests was observed.