Fireworks safety fuses

For some purposes, particularly in fireworks, instantaneous or almost instantaneous transmission of flame is required without detonation such as is characteristic of detonating fuse. Instantaneous fuse is used for this purpose, deliberate use being made of one of the possible faults in safety fuse, namely, the rapid speeding up which can occur if the core of the safety fuse is porous. 

Pyrolants deflagration detonation gas generators, igniters, fireworks, squibs, safety fuses detonators, primers, initiators, detonating fuses... 

Eye protection — safety glasses or goggles - is mandatory whenever any pyrotechnic composition is being prepared or tested. Necessary equipment includes a mortar and pestle, a laboratory balance, a soft bristle brush, several 2-3 inch lengths of fireworks-type safety fuse (available from many hobby stores), and a fireproof stone or composite slab on which to conduct burning tests. 

Comnerclal fuse, like blasting (safety) fuse, consists of a core of black powder contained In a wrapping of yam. Over the yarn are alternate layers of asphalt and cloth tape. The fuse is given s finish coat of a white clay. In the case of fireworks fuse, or wax, In the case of blasting fuse. Coimerclal fuse la available In 1/U" and 3/8" diameters, and In three different coreloads (The amount of powder eontelned In the fuse, per foot.). While the 1/L " fuse can be used In small shells, the 3/8" fuse Is more reliable and easier to use. In any case, the "heavy core" fuse should be used. 

Explosives, low Explosive materials that deflagrate rather than detonate (e.g., black powder, safety fuses, and special fireworks as defined by Class 1.3 Explosives). 

The principle of the safety match is also used in the pull-wire fuse lighter used to start a fuse train for the ignition of fireworks items or more frequently for blasting work. This is a reversed pull match whereby the striker material is coated on a pull wire, and the match head material is within a small metal cup in a cardboard tube. Pulling the coated wire vigorously out of the device ignites the match mixture in the tube for fire transfer to the tubular fuse train. 

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