Test procedure

The samples (26 x 26 cm) are placed onto an electrically heated porous plate (thermoregulation model of the human skin). The plate is placed in a climatic chamber and a fan blows air with defined temperature, humidity and velocity tangentially onto the surface of the sample. In order to avoid heat loss, the measuring plate is surrounded (underneath and on the sides) by a guard which is heated to the same temperature as the plate (35°C). The measuring surface is covered by a foil permeable to water vapour but impermeable to liquid water. Water is supplied to the plate to allow a water vapour flow from the surface. The water vapour resistance is assessed using the heating power supplied to the surface under steady-state conditions (as a measure of the amount of vaporised water), the pressure difference between the atmosphere and the plate, and the size of the plate.

If you have any queries regarding the suitability, cost or time frames associated with this testing, please do not hesitate to contact us.

Relevant standard