Concept of High-Quality Seals in Disconnectable Pipeline Connections. The "Technical Instruction Air" of the Federal Republic of Germany stipulates the use of high-quality gaskets in flange connections employed in handling of certain hazardous materials, but it gives no detailed informations concerning the high-quality criterion. This article gives reasons why the high-quality criterion should be extended on all elements of disconnectable pipeline connections of various types which are to be evaluated as systems. It further discusses the basic aspect of quality management as well as the terms ,,secluded emission" and "diffuse emission", which should be avoided or minimized respectively. The following criteria of high-quality pipeline connections are discussed : Design reserves, corrosion resistance. position fixing, safety against fracture without deformation, tightness-period and process hygiene.