本国际标准规定了一种方法，用于测定在正常环境温度下非刚性塑料在规定冲击条件下发生脆性破坏的温度。使用缺口试样的一种补充技术在比观察到的相同塑料材料的无缺口试样更高的温度下产生脆性值。该方法利用统计技术量化脆性失效温度。规定测试足够的试样，以便在统计基础上计算脆性温度。已经开发了统计技术来量化3中定义的脆性温度。 1. 该方法确定了无缺口或缺口试样失效概率为50%的温度。该方法已被发现适用于规范目的，尽管它不一定测量可使用材料的最低温度。在测量脆性温度时，在确定材料规范中使用的值时，测量精度最好为5°C（最坏情况下）。

This International Standard specifies a method for the determination of the temperature at which plastics that are not rigid at normal ambient temperature exhibit brittle failure under specified impact conditions. A supplementary technique using notched specimens develops brittleness values at a much higher temperature than are observed for unnotched specimens of the same plastic material. The method utilizes a statistical technique to quantify the brittleness failure temperature. Provisions are made for the testing of sufficient specimens to permit the calculation of the brittleness temperature on a statistical basis. Statistical techniques have been developed to quantify the brittleness temperature as is defined in 3.1. The method establishes the temperature at which there is a 50 % chance of failure in either unnotched or notched specimens. This method has been found useful for specification purposes, although it does not necessarily measure the lowest temperature at which the material may be used. In the measurement of the brittleness temperature, the precision of the measurement should preferably be _ 5 °C at the worst when establishing values used in material specifications.