DVS 2225-1-1991 "Joining of lining membranes - Made from polymeric materials (geomembranes) in geotechnical and hydraulic application - Welding, bonding by adhesives, vulcanising"
DVS 2225-2-1992 Joining of lining membranes - Made of polymer materials in geotechnical and hydraulic engineering - Site testing
DVS 2225-3-1997 Joining of sealing sheets made of polymeric materials in earthwork and water engineering - Requirements on welding machines and welding devices
DVS 2226-1-2000 history
2000DVS 2226-1-2000 "Testing of fused joints on liners of polymer materials - Testing procedure, requirements"