Flow measuring equipment at sewage treatment plants and wastewater transfer stations as well as throttle devices at stormwater overflows and rainwater overflow basins require regular maintenance and control.

In Hesse, regular inspections by state or recognized testing bodies are mandatory.

These inspection bodies have the task of carrying out those checks and tests which require special qualifications, knowledge and experience in the field of hydraulics and hydrometry. In addition, these test centres must be able to use hydrometric equipment that goes far beyond the usual equipment of an engineering firm or an operator.

The recognition of a testing body must be applied for.

Equivalent recognitions of other federal states and other member states of the European Union or a contracting state of the Agreement on the European Economic Area are recognized in Hesse. The determination of equivalence is carried out by the recognition authority in coordination with one of the state inspection bodies on request.

Wastewater is produced by the domestic, commercial, agricultural and other use of water in almost all areas of the economy and life. If necessary according to the area of origin, waste water from the commercial sector is pre-treated and sent via the public sewerage system to municipal sewage treatment plants for further treatment (indirect discharger). The treated wastewater is then discharged into a surface body of water.

In the areas of origin of waste water, which provide for corresponding de minimis regulations and requirements and for which only a notification instead of a permit is required for discharge, the discharges are monitored by expert bodies in accordance with the Indirect Discharger Ordinance. This applies, for example, to separator systems for the treatment of wastewater containing mineral oil, amalgam separators in dental practices or dry cleaning plants.

Expert bodies may act in accordance with the extent to which they are approved. Approvals may be limited to certain test areas or limited in time.

Approvals from other federal states as well as other member states of the European Union, a contracting state to the Agreement on the European Economic Area or Switzerland shall be deemed to be approvals if their equivalence has been determined by the licensing authority and published in the State Gazette for the State of Hesse.

Upon request, the calibration authorities of the Länder may grant private companies the authority to calibrate measuring instruments for gas, water, heat and electricity for the utilities industry in accordance with the Weights and Measures Act and the Calibration Ordinance.

For this purpose, the company must provide and maintain test rooms, test benches and senior test laboratory personnel in accordance with the calibration regulations.

In the recognition procedure, the competent calibration authority checks compliance with the requirements. With a certificate of recognition and a final operating permit, as well as after public appointment and commitment of the chief inspection laboratory personnel, the inspection body is authorised to carry out calibrations and diagnostic tests.

You can notify the Bayerische Ingenieurekammer-Bau (Bavarian Chamber of Civil Engineers) of the commencement of work as a testing expert for structural stability and apply for the issue of a certificate confirming that you meet the requirements as a testing expert.

You can apply to the Bayerische Ingenieurekammer-Bau (Bavarian Chamber of Civil Engineers) to take up work as an inspection expert for safety-related systems and equipment and to obtain a certificate confirming that you meet the requirements as an inspection expert.