This standard specifies a method for determining the temperature at which plastics are not rigid at normal ambient temperature exhibit brittle failure under specified impact conditions. The method considered, builds on the statistical nature of brittle failure. Some statistical techniques to measure the temperature of brittleness have been developed, as defined in subclause 3.1. The method sets the temperature at which a sample, with or without notch, produces a 50% failure. Although this method has been accepted as useful for specification purposes, it does not necessarily measure the lowest temperature at which the material can be used. When measuring the brittle temperature, the accuracy of the measurement should preferably be 5 ° C as worst value when values used in the material specifications are set. NOTE notched samples can be used as an additional technique. In this case, brittle failures occur at higher temperatures for the same plastic material