How physically unstable is nitroglycerin?

As nitroglycerin contains oxygen, nitrogen and carbon, an explosion is essentially rapid combustion - the three nitrate groups (powerful oxidizing agents) are bound directly to a hydrocarbon fragment (a fuel). Hence releasing a large amount of energy (exothermic reaction) because the atoms rearrange to form new molecules with strong, stable (multiple) bonds, such as N2 and CO. 4C3H5N3O9(s) →6N2(g) + 12CO(g) + 10H2O(g) + 7O2(g) Pure nitroglycerin is a contact explosive (physical shock may result in an explosion), which degrades over time, producing even more unstable chemical forms. As a result nitroglycerin is highly dangerous to transport or handle. The undiluted form it is one of the most powerful high explosives, analogous to military explosives RDX and PETN, along with the plastic explosive C-4.