This technical report gives guidance to technical committees wishing to develop lists of maximum allowable temperatures for polymeric compounds under normal and abnormal operating conditions. It discusses and makes recommendations concerning: a) the factors which influence the choice of an appropriate method of describing polymeric compounds, bearing in mind the complex recipes of many compounds and the resulting wide ranging properties (see 5.1); b) the factors which influence the selection of data for inclusion in lists of maximum allowable temperatures for polymeric compounds under normal operating conditions (see 5.2 and 5.3); c) lists for the maximum allowable temperatures for polymeric compounds under abnormal operating conditions (see clause 6). In this report the term "temperature" is used, although it is realized that it is customary to use "temperature rise" for practical reasons. One may be converted into the other, given an appropriate reference point, e.g. 25 ℃.