Based on the practical experience and research findings of Prof. Dr.-Ing. Stein and Partner GmbH and literature research, the following suggestions and recommendations should be considered to ensure a professional use of high-pressure cleaning in order to avoid damages:

• In choosing the operating parameters (nozzle type, flow rate, angle of radiation, and pressure at the nozzle), the pipe material, the wall thickness, and especially the structural condition of the sewers should be taken into consideration in addition to the core task of cleaning.

• The sewers should not be cleaned one section at a time but rather, if possible, in entirety from the first section down to the inlet of the main collector to efficiently collect and retrieve all removed deposits.