DIN 4741-2
DIN 4741-2
Ventilation plant; type 1 polypropylene (PP) uptakes; pipe fittings, bends; minimum wall thicknessesstandard by Deutsches Institut Fur Normung E.V. (German National Standard), 08/01/1987
standard by Deutsches Institut Fur Normung E.V. (German National Standard), 08/01/1987