Wet strength of paper or board

In this test, performed following the ISO 3781 standard, the tensile strength of paper or board is measured after the material has been immersed in water for a specified period.

The test can be used to evaluate the functionality of board and paper that may be exposed to water at some point during use, such as packaging materials. The analysis does not work for papers that don't hold their shape when wet or have very low wet strength.