This part of ISO 9924 specifies a thermogravimetric method for the determination of the main constituents of rubber compounds such as elastomer(s), carbon black and mineral filler. It establishes the “fingerprint” of the tested material. However, the result does not always correspond exactly to the theoretical formula of the rubber. This method applies to raw or compounded rubbers, vulcanized and unvulcanized, after preliminary extraction. This method applies to rubbers with hydrocarbon backbones (NR, BR, SBR, IIR, EPDM, ACM, AEM, etc.) used alone or as mixtures. For the mixtures, the polymer content corresponds to the total rubber, and it is not usually possible to identify individual polymers. This method applies to rubbers with halogenated hydrocarbon backbones (CR, CSM, FKM, CM, CO, ECO, etc.) or containing nitrogen (NBR, HNBR, NBR/PVC, etc.), as well as to their mixtures. However, these rubbers often form carbonaceous residues which interfere with the analysis. Application of an appropriate procedure minimizes these interferences. This method also applies to rubbers with a polysiloxane backbone (VMQ, etc.) and to rubbers not listed above.