Shock sensitivity

The impact sensitivity refers to the behavior of a substance (usually of an explosive ) to mechanical stress. The criterion is that the material under the action of a defined impact energy decomposes explosively with an audible bang.

Method

As the test method by the Federal Institute for Materials Research and Testing ( BAM) developed monkey test will be used. This made ​​possible by the fall of a weight from a certain height on a test piece, the test with a defined impact energy. This is calculated as the product of drop height and weight and is in the unit joule ( J) specified.

Classifications

For the purposes of the Explosives Act and Directive EC 440/2008 of the European Commission applies a limit of 40 joules under which it is classified as a potentially hazardous substance. The monkey test belongs in addition to checking on friction sensitivity and the steel sleeve test to those required under the Explosives Act checks. The test is described as a test 3 (b) ( i) within the test series 3 part of the testing schemes for the classification of explosives of Class 1 in accordance with the Technical Instructions.

Examples

Substances with high sensitivity to impact ( impact energy <0.5 J ), such as nitroglycerin or nitrogen trichloride must be well protected from knocks and bumps, otherwise they very easily detonate. Other examples of explosives ( sorted in order of decreasing impact sensitivity ) are silver azide ( impact energy 1 J), PETN ( 3 J), picric acid (7.5 J), trinitrotoluene ( 15 J ) and ammonium perchlorate (25 J).