Article 2 of European Community Directive 96/82/EC (known as 'Seveso-II' Directive) also requires consideration in the plant inventory of the dangerous substances 'which it is believed may be generated in the loss of control of an industrial chemical process'. The present study was directed to the further development and assessment of procedures for the identification of products formed in the 'loss of control' of chemical systems caused by exothermic decomposition reactions. The specific aim was the development of procedures for the sampling and identification of products formed in four different scale experimental devices and the comparison of the results obtained. The methodologies developed were tested on ethyl diazoacetate (EDA). The results obtained indicated that sufficient agreement was present in the data obtained for the thermal effects and for the apparent kinetic parameters of the thermal decomposition. On the other hand, the analysis of the decomposition products showed important differences both from the qualitative and quantitative point of view. Operating conditions such as pressure, heating rate, and residence time in the hot zones of the experimental devices may become critical factors if a quantitative analysis of decomposition products formed is required. Therefore, the development of standard experimental procedures seems to be necessary in order to apply Article 2 of the 'Seveso-II' Directive. © 2003 Elsevier Ltd. All rights reserved.