Eight com. activated cokes used for treatment of off-gases from combustion were tested for ignition temp. by 3 std. methods to det. the effect of oxidizing agents, heating rate, gas flow rate and the fragmentation of the sample. The ignition temp. decreased with increasing O-2 flow rate and sp. surface of the coke but did not depend on the heating rate of the coke bed. The differences in ignition temp. detd. by particular methods were described by linear equations in function of the coke grain size.