The thermal degradation of polyamide 6, polyacrylonitrile and of a polyurethane rigid foam was studied using two different thermal analyzers with coupled techniques for the evolved gas analysis (TA-MS and TA-FTIR) and two combustion devices. For the thermal analyzers samples about 5 and 20 mg were used under a heating rate of 10 K min(-1). The products from the combustion of the samples (40 mg) at 800-1000 degreesC are described. An adequate clean up method was used to determine the different species of nitrogen containing products evolving during the pyrolysis of the samples.