It is the determination of waterproofing properties of fabrics by hydrostatic pressure method. It is especially applied to fabrics such as thick fabrics, tarpaulins and awnings. ( TS 257 EN 20811)
Used materials
Water permeability device with hydrostatic pressure (water pressure increase rate can be adjusted to 10 ± 0,5 cmH2O or 60 ± 3 cmH2O per minute), Test sample head can hold the test sample in 100 cm² area, Pure water we use in this test (20±2)°C should be at temperature.
Sample preparation
At least five test samples are taken from different parts of the fabric without wrinkles and folds. The test sample is cut to dimensions that cover 100 cm² of the test head. After the test sample is taken, it is handled as little as possible.
Experimental Procedure
The water pressure increase rate (10 ± 0,5 cm H2O/minute or 60 ± 3 cm H2O/minute) to be applied for the test sample is adjusted on the device manometer.
The spirit level on the test head is adjusted.
The water in the place where the test sample will be attached to the jaw is wiped off.
The test head area where the test specimen will be placed is filled with water and attached to the test head in such a way that the surface of the test specimen comes into contact with water so that the water does not push the specimen.
The start button of the device is pressed to apply increased water pressure to the test sample.
Increasing water pressure is applied to the sample.
The water permeability of the fabric is constantly observed.
The water pressure at the exit of the third water drop from the test sample is recorded.
Drops emerging from the same point on the fabric are not taken into account, and very small drops that do not grow after forming are not taken into account.
The arithmetic average of the pressures recorded for the samples subjected to the test is taken.
