Water vapour permeability

Testing

When determining water vapour permeability, the material to be tested is placed in a laterally sealed container which is open at the top and contains a desiccant. The test arrangement is placed in a test climate with controlled temperature and humidity conditions. Due to the water vapour partial pressure difference between the test climate and the test vessel, water vapour flows through the test sample. The water vapour diffusion flow density is determined by means of periodic mass determination when the stationary state is reached.

Standard

DIN EN ISO 4892-2
Plastics – Methods of exposure to laboratory light sources – Part 2: Xenon-arc lamps

DIN EN 12086
Thermal insulating products for building applications – Determination of water vapour transmission properties

(The tests are not in the accredited area of the PfB)