The diploma thesis deals with evaluation of selected polyethylene, polypropylene, polyvinyl chloride and polyurethane. At present, plastics are increasingly being applied to the market and it is therefore essential that we know how to behave in high temperature. The aim of the thesis was to evaluate the flammability of selected plastics using STN ISO 1210. Attention was paid to drainage time, weight loss, burning time and linear burn rate. The experiment was performed on 2 sets of 3 samples, the first set being conditioned under laboratory conditions - a temperature of 23 °C and a relative humidity of 50 % for 48 hours, and the second set was aged at 70 °C for 168 hours. Samples were tested using two test methods. Method A was used to determine the horizontal rate of burning of horizontal samples, and Method B to determine the time of self-sustaining flame burning or spontaneous heater in vertical samples. The results of the tests were the classification of the fire characteristics of the materials. Horizontal samples were classified into one of 4 FH classes (horizontal burning) and vertical samples were classified into FV classes (vertical burning). We found that after aging samples were slightly worse than test specimens that were conditioned under laboratory conditions