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In this paper the results are presented of drop tests simulating falling objects into a melt of ammonium nitrate which may happen in the case of a fire. During such a fire parts of a collapsing building may fall into molten ammonium nitrate. One of the conclusions from investigations performed in Canada was that the impact sensitivity of such a melt would be in the same class of shock sensitivity as nitroglycerine. This caused the concern of the relevant industry and resulted in the execution of the test programme presented here. In the various tests performed no detonation has been observed even under the most severe test conditions. Exposition of pure nitroglycerine to the same conditions would certainly have resulted in a detonation. This test could not be performed for safety reasons. It thus may be concluded that molten AN is less sensitive than nitroglycerine. Additional tests have to show the difference in the initiation behaviour of both substances. It is unlikely that a detonation of molten AN may result from impact forces of collapsing buildings.

The explosive properties of mixtures of hydrogen peroxide and isopropanol were determined The mixtures appear to detonate in a well-defined range of concentrations and show extremely fast reactions in an adjacent range of concentrations if initiated by shock wave stimuli. The upper boundary of organic matter concentrations at which initiation can be initiated appears to depend on temperature by margins of about 10 to 15%. The lower boundary is hardly affected by temperature Initiation by exposure to heat may lead to detonation as well. This implies that venting may not be sufficient to reduce the hazard at these concentrations. The range of concentrations at which detonable properties were observed upon initiation by thermal stimuli is similar to the ranges observed with shock stimuli The test (SCB) and test procedure applied in testing with thermal stimuli appear to be very suitable for this type of testing.