To trigger an explosive device a detonator is used. Detonators can be chemically, mechanically, or electrically connected.
The commercial use of explosives uses electrical detonators or the capped fuse which is a length of safety fuse to which an ordinary detonator has been crimped. Many of the detonators' primary explosive is a material called ASA compound.Lead azide, lead styphnate and aluminium and is pressed into place above the base charge, usually TNT or tetryl in military detonators and PETN are used in the formation of commercial detonators.
Other materials such as DDNP (diazo dinitro phenol) are also used as the primary charge to reduce the amount of lead emitted into the atmosphere by mining and quarrying operations.Mercury fulminate as the primary, and it was often mixed with potassium chlorate in old detonators to give better performance
TYPES OF DETONAORS
Electrical detonators are basically of three types: 1.instantaneous electrical detonators (IED),
2. short period delay detonators (SPD) and
3. long period delay detonators (LPD). SPDs are measured in milliseconds and LPDs are measured in seconds.
A new development is a slapper detonator, which uses thin plates accelerated by an electrically exploded wire or foil to deliver the initial shock. It is in use in some modern weapon systems.
Non-electric detonators usually take the form of an ignition-based explosive. Whilst they are mainly used in commercial operations, non-electric detonators are still used in military operations. This form of detonator is most commonly initiated using safety fuse, and used in non time-critical detonations i.e. Conventional Munitions Disposal