Testing Services for the paper, nonwovens, packaging, and consumer products industries.

Have questions? Give us a call 920-749-3040

ISO 5636-5 Porosity (Gurley)




ISO 5636-5


Determination of air permeance (medium range) — Part 5: Gurley method


This part of  ISO 5636-5 Porosity specifies the Gurley method for determining the air permeance of paper and board using an air resistance tester, the Gurley apparatus.

It is applicable to papers and boards which have air permeances between 0,1 µm/(Pa•s) and 100 µm/ (Pa•s) when tested with the Gurley apparatus.

It is unsuitable for rough-surfaced materials, which cannot be securely clamped to avoid leakage.

This part of ISO 5636 may also be used to determine the air resistance of paper and board.


The air is compressed by the weight of a vertical cylinder floating in a liquid. A test piece is in contact with the compressed air and the cylinder falls steadily as air passes through the test piece. The time for a given volume of air to pass through the test piece, i.e. the air resistance is measured and from this the air permeance is calculated.


Maximum test time is 60 minutes. For non-standard materials or extended test times, call for estimate.

Please note:
SGS-IPS cannot sell or otherwise provide standards, specifications, or test procedures to third parties.