A Source of Systematic Error in Transient‐Flow Air Permeameter Measurements

Abstract The data from transient‐flow air permeameters often exhibit curvature in the theoretically linear plots of the natual log of pressure vs. time. This was originally attributed to errors in water manometer data caused by the inertia of the water in the manometer. The resulting recommendation was to ignore the early time data when calculating the air permeability of a soil by these methods. We have demonstrated and quantified that the …