The initiating explosive is called the donor explosive, the initiated one is known as the receptor explosive. In case of a chain detonation, a receptor explosive can become a donor one.
The shock sensitivity, also called gap sensitivity, which influences the susceptibility to sympathetic detonations, can be measured by gap tests.
If detonators with primary explosives are used, the shock wave of the initiating blast may set off the detonator and the attached charge. However even relatively insensitive explosives can be set off if their shock sensitivity is sufficient. Depending on the location, the shock wave can be transported by air, ground, or water. The process is probabilistic, a radius with 50% probability of sympathetic detonation often being used for quantifying the distances involved.
Sympathetic detonation presents problems in storage and transport of explosives and ordnance. Sufficient spacing between adjacent stacks of explosive materials has to be maintained. In case of an accidental detonation of one charge, other ones in the same container or dump can be detonated as well, but the explosion should not spread to other storage units. Special containers attenuating the shock wave can be used to prevent the sympathetic detonations; epoxy-bonded pumice liners were successfully tested.Blow-off panels may be used in structures, e.g. tankammunition compartments, to channel the explosion overpressure in a desired direction to prevent a catastrophic failure.
A related term is cooking off, setting off an explosive by subjecting it to sustained heat of e.g. a fire or a hot gun barrel. A cooked-off explosive may cause sympathetic detonation of adjacent explosives.