54. Apparatus54.1 Tear resistance shall be measured on a power-drivenmachine, which will indicate the maximum force, by mechanical or electronic means, at which rupture of the specimen takesplace.55. Test Specimens55.1 The test specimens shall be a block shape free of skin,voids, and densification lines, as shown in Fig. 4. They shall becut on a saw from sheet material ensuring that the sides areparallel and perpendicular to each other. A nominal 40-mm cutshall be placed in one side as shown in Fig. 4. Dimension A-Bcan be reduced to the pad thickness. The thickness shall bedetermined in accordance with Section 8