A total of 10 tests were carried out to investigate the effect of fuel load, openings and ignition location on the fire development in a metro car. The fuel loads consisted of polyurethane (PUR) seats, wall and floor coverings, and in some tests longitudinal wood cribs simulating the passengers’ luggage. Different parameters including: heat release rate, gas temperature, gas concentration, heat flux and smoke density, were investigated. The results show that the fuel load and its placement plays an important role in the fire development in the metro cars included in this study. However, the opening, i.e. doors and windows, was also found to significantly affect the results. In tests with large openings the fire grew more rapidly. The maximum heat release rate was found to increase with the area of the openings since more rapid fire development resulted in an increase amount of fuel burning simultaneously. The location of the ignition source was found to have a limited influence on the fire development. When the ignition source was placed between the doors DR1 and DR2 the fire growth rate increased, however, this did not affect the maximum heat release rate significantly.