The Dart Impact Tester (Falling Dart Impact Tester/Dart Drop Impact Tester) evaluates impact rupture strength by measuring impact energy applied to plastic films.
ISO 7765-1 - Plastics film and sheeting – Determination of impact resistance by the free-falling dart method – Part 1: Staircase methods
ASTM D1709 - Standard Test Methods for Impact Resistance of Plastic Film by the Free-Falling Dart Method