The European certification systems for radiators include a third-party monitoring process with regard to the quality of the manufacturing processes. This assessment ensures not only a high quality during the manufacturing process for radiators, but also that performance values determined during the test can be transferred to all structurally identical radiators. The third-party monitoring process is carried out by means of annual inspections. A European agreement between the certification bodies, the RADMAC (RADiators Mutual Acceptance of Certification), stipulates that one inspector carrying out the inspection can cover all of the relevant certification marks to reduce costs. During the inspection, the inspector takes product samples of the radiators to be checked for all certification marks the manufacturer applied for.

WSPLab carries out inspections for the RAL Gütergemeinschaft Heizkörper aus Stahl (German Quality Assurance Association for Steel Radiators) within the framework of the RADMAC agreement.