Certification of our vitrified clay pipes

Assured quality of sewage pipes

All of our products stand for quality. Quality signifies safety and reliability. Safety and reliability create trust – trust in what we make. We manufacture our pipes and components diligently and in full accord with sophisticated technologies – at the very highest level.

Standards for vitrified clay pipes are specified by EN 295, parts 1 to 7. In addition, our products are produced and inspected in compliance with the ZP WN 295 certification programme, which in part includes significantly higher demands than EN 295.

Our own internal monitoring, voluntary external monitoring and usage rights for various quality labels – as well as, for example, the quality labels of the MPA, NRW, Benor, NF, SKG-IKOB and Qplus – represent special certification of the quality of our entire product range, the high standards of which go beyond the legal and normative stipulations of the EN 295 European standard.

More importantly, these quality labels create trust for the customer, who can rely unreservedly on the assured attributes of our products. At the same time, they document the existence and use of an ISO 9001:2015-compliant quality management system.


Compliance with norms and standards, guidelines, worksheets etc. laid down by the regulatory framework, is essential for the proper installation of sewer constructions. They guarantee high performing standards in accordance with the current state of technology. But the willingness of each individual to take responsibility for man and environment is an equally indispensible component of the realisation of such construction projects.

EN 295, including parts 1 to 7, applies as a product standard for vitrified clay pipes, fittings and accessories.

EN 1610, EN 752, EN 1295, DWA A 139 and DIN 18306 apply for open construction.

EN 1610, EN 1295, EN 12889, A 125 and DIN 18319 as well as GSTT Information No. 24 "Planning" apply for trenchless construction.

Further information


Further information about certificates can be found in our Infopool.

Pipes and fittings

Find out more about the properties of our pipes and fittings.


Find out more about the functional properties of joints.