The immersion depth describes the distance between the lower edge of the component to be sealed and the design water level, i.e. the maximum depth at which the waterproofing may stand in the pressing water.
DIN 18533-1 (Waterproofing of components in contact with the ground, Part 1: Requirements, planning and implementation principles) specifies the water action classes against pressing water depending on the immersion depth: Up to an immersion depth of 3.0 m, water exposure class W2.1-E applies, and water exposure class W2.2-E applies to an immersion depth > 3 m.
Source: bauwion
