This International Standard specifies a test method for laboratory measurement of the hydraulic conductivity of water-saturated porous materials using a flexible wall permeameter. This International Standard is applicable to undisturbed or compacted specimens that have a hydraulic conductivity between 1 × 10−5 m/s (1 × 10−3 cm/s) and 1 × 10−11 m/s (1 × 10−9 cm/s). Typical soil types falling in this category are clay, clay and sand tills, silt, peat, mud, etc.