Determining the extinguishing effectiveness of extinguishing agents against solid fires is difficult. This is mainly due to the large variety of combustible materials. These difficulties also concern the determination of the effectiveness of various extinguishing agents for gas, fat and metal fires. However, extinguishing tests for liquid fires are defined very precisely. The tests of the effectiveness of powder materials, such as extinguishing powders, are based on relatively simple and methods used to extinguishers testing. It does not eliminate the very significant impact of the human factor on the test effect. A cone calorimeter was used for comparative evaluation of the extinguishing efficiency of bulk materials. For this purpose, bulk materials e.g. salt, sand and dry chemicals were applied to the surface of standard pine wood samples and the differences in their flammability were examined. Based on the analysis of HRR, weight loss curves and time to achieve flame combustion, it was found that a cone calorimeter can be used to pre-assess the effectiveness of extinguishing the dry powders and dry chemicals for solid fires. There were clear differences between chemical and only physical effects.