We present our results on the comparison of two methods for the SADT determination. Both methods, UN test H.1 and UN test H.4 are recommended by the international transport regulations from the UN. But during the last years the applicability of the UN test H.4 has been questioned for solid substances. Therefore, three organic peroxides and one self-reactive substance have been investigated in 5 kg and 20 kg packages as well as in the UN test H.4 in a 500 mL Dewar vessel. The SADT values determined with the different methods match. The UN test H.4 seems to be well suited for solid organic peroxides and self-reactive substances of at least 20 kg or 60 L (C) 2010 Elsevier Ltd. All rights reserved.