At the evaluation of fire properties of given material the primary importance has determining in what conditions and as quickly will ignite. It is valid for determining, which material will ignite at first as well as for determining the development of the fire in the room do to "remote" inflammations or as a result of spread the flame by the area. The ignitability in the fire is characteristic by properties of the material and can be calculated from data from examinations in small scale. These calculated properties are used to predict ignition in real fire (at the assumption that they are known or determined in computer models of the development of the fire). For the ignitability determination research methods, in which the thermal exposure can be radiation, convection type or acting of the flame. At the work testing methods according to ISO 11925-3 of the source A-H and results of testing were presented.