Safety squibs

The primary safety considerations in the formulation, manufacture, and use of explosives are that they must never explode prematurely but always explode when desired. Often this balance is achieved with an insensitive main charge being initiated by the least amount of a more sensitive explosive. This concept is expanded to that of an explosive train in which a series of decreas-ingly sensitive explosives is ultimately sufficient to initiate an insensitive main charge. The sensitivity of explosives to initiation provides a common means of classification  

Other explosives may be added to explosive trains to sensitize certain components or add a time delay. There are as many combinations as necessary to 

Mercury fulminate detonators were widely replaced due to their extreme sensitivity. Contemporary simple nonelectric detonators contain a small quantity of primary explosive (often lead azide) which, once ignited by a fuse, ignites the more powerful base charge of a secondary explosive (an additional low explosive may be used between the fuse and the primary explosive). 

Often another controlled volume of low explosive is placed between the matchhead and the primary charge. This bums for a specified period introducing a delay (from a few milliseconds to a few seconds) into the detonator. However, any low explosive delay device syn. delay electric igniter) introduces imprecision because the chemicals are affected by moisture, temperature, and time. High precision delay electric detonators implant the match-head directly into the primary explosive and control the delay with an integrated circuit within the detonator. 

Detonators for ammunition include primary explosives to detonate the main charge. They may or may not be co inected to a fuze. 

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Squibs are cotton yams or other fibres impregnated with black powder and which bum with an external flame to ignite pyrotechnics, although the term may apply to small pyrotechnic or explosive devices. Safety squibs are those squibs which do not bum with an external flame. Electric squibs are essentially synonymous with the matchheads (bridgewire-low explosive combinations) used in electric detonators as well as a type of jet thmst igniter. 

A little gunpowd is added at the end in order to facilitate ign of the slow match. When used, the squib is inserted with the slow match outward in a hole made in a charge of BkPdr blasting expl. When the match is lit, the fire burns slowly, allowing the miner time to reach a place of safety. As soon as the fire reaches the BkPdr core of the squib, it burns fiercely and then suddenly explodes, igniting the blasting expl. Instead of the paper tube, quills filled with fine BkPdr joined to a slow match, can be used... 

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

In the DuPont s Hdb (Ref 50, p 187), the device consisting of a paper cartridge of BkPdr in which a safety fuse is inserted is called black powder primer with safety fuse, and the device Combining a BkPdr cartridge with an electric squib or cap is called black powder primer with electric squib or cap. 

Initiation by ignition) 291 (Initiation by percussion) 294 (Initiation by detonation and detonators) 318 (Igniter pad in separate-loading ammunition) 331 (Safety fuse) 332 (Squibs) 332 (Blasting caps) ... 

It is a Iso good practice to ha ve a grea ter gap so that the safety factor can be established. Depending on the type of fuzes being tested they are fired by applying a load or using electric squibs, etc (p IIB-32 of Ref 39)... 

Igniters are used for igniting propellant charges, pyrotechnics, some fuzes, demolition charges and some special items. The simplest igniters are safety matches and squibs which are used to ignite safety fuses... 

In first developmental studies, containers were made with polyurethane. However, it was found (Ref 1) that medium density polyethylene is an ideal material to fabricate expl safety containers. Two different sizes of containers were developed by Zimmer Asaoka a 10-cm diameter container which can easily withstand the expln of 15g of NG and a 32-cm diameter 500g of NG, if small detonators (DuPont S 67 squib) are used. The smaller container weighs 0.775 kg and is easily carried in one hand the larger container weighs less than 22kg and is easily portable with carrying handles or in a cart... 

Zundpille = squib 296 Ziindschalter = blasting switch 38 Ziindschnur = safety fuse 271, 276 Ziindschraube = fuze head 148 Ziindsicherung = igniter safety mechanism 184 Zundstrom = firing current 141 Ziindung = initiation 191 Ziindverzug = functioning time 77 147... 

Electrical igniter (commercial SQUIB or improvised igniter, Section VI, No. 1). Safety or improvised fuse may also be used. 2. Light safety fuse when ready to fire. 

The safety airbag module (squib) circuit resistance can even not be tested by the designated tester. 

Typically are intended to include explosives, blasting agents, and detonators, including dynamites, slnrries, emulsions and water gels, black powder, smokeless powder, detonators and safety fuses, squibs, detonating cord, and other materials whose primary fnnction is to fnnction by explosion. 

BLACK POWDER GRANULES (See color insert following page 112) Black powder granules are the first commercial energetic material, and have remained an article of commerce for over one thousand years. This unique blend of potassium nitrate (saltpeter), charcoaL and sulfur (brimstone) has served as an explosive, a propellant, and a component in pyrotechnic devices such as safety fuse and squibs. (Photo by Tim Wade and Dennis King, courtesy of MP Associates.)... 

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