DIN EN 1433 classifies drainage channels into load classes analogous to manhole covers. The classification is made by means of a load test. We regularly subject our reinforced concrete »Pfuhler Rinne« slot units to appropriate load tests, together with a certified test institute. However, on request, we can also supply reinforced concrete slot units, whose load bearing capacity is additionally verified, taking into account the respective loading and installation conditions according to accepted good practice for reinforced concrete construction (DIN 1045-1). Road traffic loads are applied according to the DIN technical report 101, loads on airfield and airports correspond to the recommendations of the "Arbeitsgemeinschaft Deutscher Verkehrsflughäfen" (ADV). A comparison can be drawn below  between the DIN EN 1433 classification and the structural calculation (see table below).

Class D 400 channels correspond to Type I to DIN EN 1433; i.e. they do not require a foundation to absorb loads in the installed condition to dissipate the loads that occur during use. Class F 900 channels correspond to Type M. They must be laid on a structurally calculated reinforced concrete foundation.