Air permeability of paper or board

Air permeability is an important property for some paper grades, such as paper bags that are filled industrially. Measurlabs offers air permeance testing with the Bendtsen and Gurley methods.

The Bendtsen method (ISO 5636-3) is suitable for papers with permeance from 0.35 µm/(Pa*s) to 15 µm/(Pa*s). It is not suited for rough-surfaced papers that cannot be securely clamped to the device. The results are reported in ml/min, expressing the average volume of air that passes through the material in a minute at elevated pressure.

The Gurley Method (ISO 5636-5) is suitable for papers with permeance between 0.1 µm/(Pa*s) and 100 µm/(Pa*s). The test may also be used to determine the air resistance of paper and board. In the Gurley test, the time it takes for a certain volume of air to pass through the paper at a certain pressure is measured in seconds.