ASTM D 1709 : 2016 : REV A : EDT 1

1.2.1Test Method A employs a dart with a 38.10 ± 0.13-mm (1.500 ± 0.005-in.) diameter hemispherical head dropped from a height of 0.66 ± 0.01 m (26.0 ± 0.4 in.). This test method can be used for films whose impact resistances require masses of about 50 g or less to about 6 kg to fracture them.

1.2.2Test Method B employs a dart with a 50.80 ± 0.13-mm (2.000 ± 0.005-in.) diameter hemispherical head dropped from a height of 1.52 ± 0.03 m (60.0 + 0.25, −1.70 in.). Its range of applicability is from about 0.3 kg to about 6 kg.

1.3.1The standard technique is the staircase method. By this technique, the missile weight employed during the test is decreased or increased by uniform increments after the testing of each specimen, depending upon the result (fail or not fail) observed for the specimen.

1.3.2The alternative technique provides for testing specimens in successive groups of ten. One missile weight is employed for each group and the missile weight is varied in uniform increments from group to group.

1.3.3The staircase technique and the alternative technique give equivalent results both as to the values of impact failure weight which are obtained and as to the precisions with which they are determined.