瓦楞介质的吸水率是通过将一滴水滴在试样表面，并确定水滴穿透板材并湿润下表面的时间（以秒为单位）来测量的。该方法适用于瓦楞介质，因为它是通过所有工艺进行商业生产的。它通常适用于尺寸相对较小（水叶）的纸板，但可能不适用于尺寸更大的纸板，或不同于瓦楞介质中通常使用的重量（基重）生产的等级。可在相同的一般时间段内以相同的重复性执行的替代方法不会给出相同的数值结果，但通常情况下，将按照与该方法相同的顺序对材料进行排序。

The water absorptivity of corrugating medium is measured by dropping a drop of water on the surface of a specimen and determining the time in seconds for the drop to penetrate through the sheet and wet the lower surface.This method is applicable to corrugating medium as it is commercially produced by all processes. It is generally applicable to relatively unsized (water leaf) containerboards but may not be applicable to more highly sized boards or to grades produced in different grammage (basis weight) than those normally used in corrugating medium. Alternative methods which can be performed in the same general time period with equal repeatability do not give the same numerical results, but, in general, will rank the materials in the same order as this method.