IEC 60216-8:2013规定了用于推导耐热特性的一般老化条件和简化程序，其通过温度指数（TI）和/或相对温度指数（RTI）和减半间隔（HIC）表示。 这些程序规定了评估长期暴露在高温下的材料耐热性的原则。在本标准的应用中，假设引起预定性能变化所需时间的对数与相应绝对温度的倒数之间存在实际线性关系（阿累尼乌斯关系）。 为了有效应用本标准，在研究的温度范围内不应发生任何转变，尤其是一阶转变。

IEC 60216-8:2013 specifies the general ageing conditions and simplified procedures to be used for deriving thermal endurance characteristics, which are shown by temperature index (TI) and/or relative temperature index (RTI) and the halving interval (HIC). The procedures specify the principles for evaluating the thermal endurance properties of materials exposed to elevated temperature for long periods. In the application of this standard, it is assumed that a practically linear relationship exists between the logarithm of the time required to cause the predetermined property change and the reciprocal of the corresponding absolute temperature (Arrhenius relationship). For the valid application of the standard, no transition, in particular no first-order transition should occur in the temperature range under study.