The calibration of the sewer section to be rehabilitated is a special service. The results of the calibration are to be documented in a calibration protocol and form the basis for the production of the lining rube and further work processes. As an additional service, at least the nominal diameter and the circumference of the host sewer must be determined at all manholes involved due to the lining tube installation.

If during calibration or measurement of circumference and nominal diameter at the manholes deviations from the specifications of the client are found, the client should be informed immediately. In particular in the case of varying profile sizes within a sewer section to be rehabilitated, the dimension to be used for the manufacturing of the lining tuber must be agreed jointly between the contractor and the customer.