Detonator

Small explosive device used to trigger a larger explosion Top: small nonel detonator with 2 ms delay for chaining nonel tubes; middle: class B SPD detonator; bottom: class C SPD detonator Inserting detonators into blocks of C-4 explosive A detonator or blasting cap is a small explosive device or small quantity of explosive, which can be combined with a fuse, used for detonating a larger charge of high explosive. Detonators come in a variety of types, depending on how they are initiated (chemically, mechanically, or electrically) and details of their inner working, which often involve several stages. Types of detonators include non-electric and electric. Non-electric detonators are typically stab or pyrotechnic while electric are typically "hot wire" (low voltage), exploding bridge wire (high voltage) or explosive foil (very high voltage). The original electric detonators invented in 1875 independently by Julius Smith and Perry Gardiner used mercury fulminate as the primary explosive. Around the turn of the century performance was enhanced in the Smith-Gardiner blasting cap by the addition of 10–20% potassium chlorate. This compound was superseded by others: lead azide, lead styph