Meeting TRGS 519 Standards: Efficient and Safe Asbestos Cement Pipeline Rehabilitation

Abstract

This paper presents a trenchless method for rehabilitating asbestos cement (AC) pressure pipelines using a low-emission relining system. The approach eliminates pipe removal, minimizes hazardous fibre release, and complies with stringent occupational safety regulations, particularly TRGS 519 (Technical Rules for Hazardous Substances). Recognized by Germany’s DGUV (German Social Accident Insurance) as lowemission procedure BT 62, the Primus Line® system is currently the only drawn-in liner method with this classification. Independent monitoring of three projects in 2023 confirmed fibre concentrations well below the legal threshold of 10,000 fibres per cubic metre. A defining feature is its loose-fit liner concept, codified in ASTM F3708-25, which leaves the AC host pipe intact and isolates it from internal pressure. This prevents fibre release, avoids creating asbestoscontaminated excavation waste, and provides clear environmental benefits compared with destructive alternatives such as pipe bursting. In addition, according to the NASTT Carbon Calculator, Primus Line® trenchless rehabilitation can reduce greenhouse gas emissions in construction by up to 90% compared to conventional open-cut replacement. The German approval of BT 62 provides a strong precedent for Australia and New Zealand, where Primus Line® Rehab offers operators a safe, sustainable, and legally robust solution for extending the life of AC pressure pipelines.