DVS 2212-2-1992 Examination of plastic welders - Examination group II - Hot gas extrusion welding
DVS 2225-1-1991 "Joining of lining membranes - Made from polymeric materials (geomembranes) in geotechnical and hydraulic application - Welding, bonding by adhesives, vulcanising"
DVS 2207-4-1993 history
2013DVS 2207-4-2013 "Welding of thermoplastic - Extrusion welding of pipes, piping parts and panels - Processes and requirements"
2005DVS 2207-4-2005 "Welding of thermoplastic - Extrusion welding of pipes, piping parts and panels - Processes and requirements"
1993DVS 2207-4-1993 Welding of thermoplastics - Extrusion welding - Panels and pipes