Fireworks industry

Other typical pyrotechnic fuels include charcoal, sulfur, boron, siUcon, and synthetic polymers such as poly(vinyl alcohol) and poly(vinyl chloride). Extensive use has been made of natural products such as starches and gums, and the use of these materials continues to be substantial in the fireworks industry. MiUtary pyrotechnics have moved away from the use of natural products due to the inherent variabiUty in these materials depending on climatic conditions during the growth of the plants from which the compounds are derived. 

The effect of initiators (diluted sulfuric acid, chlorine dioxide, sulfur dioxide or disulfur dichloride) on ignition of mixtures of barium, lead or potassium chlorates with sulfur was examined [1] Presence of copper ion or metal (e.g. from a sieve) may also lead to explosion of such mixtures [2], A review of hazards of sulphur/chlorate mixtures in the firework industry has been published [3],... 

The fireworks industry also benefited from these improvements, which was reflected in the growing popularity of organised displays and the diversity of the pyrotechnic effects so presented. 

All of this was subsequently of great benefit to the British fireworks industry, of course, which has capitalised on the 5th of November celebrations ever since. However, any other country in the world might have bent the truth a little and claimed in the history books that the plot... 

It can be taken as axiomatic that every person in the fireworks industry recognises that they are dealing with potentially dangerous substances... 

The fireworks industry in the UK is too small to warrant continuous attention by Parliament, but two corporate bodies have been established in accordance with the Health and Safety at Work Act that control safe practices within factories, including fireworks factories, and this, in turn, ensures a safe standard of products that reach the general public. 

J.C. Cackett, T.F. Watkins and R.G. Hall, Chemical Warfare, Pyrotechnics and the Fireworks Industry, Pergamon Press Ltd, London, 1968. 

The historical material - stemming from several well known sources -is valuable for its technical content. The subject matter then advances to a presentation on the characteristics of gunpowder, whose unique properties cause it to be the mainstay of the fireworks industry, even today. 

As with the modern fireworks industry, pressing is preferred over more forceful techniques, but even so, hres regularly break out in presses. Milling is not without hazard either, especially when the large wheel mills weigh several tonnes and the powder batch is around 150 kg. 

The "newest" oxidizer to appear in pyrotechnics, ammonium perchlorate has found considerable use in modern solid-fuel rocket propellants and in the fireworks industry. The space shuttle alone uses approximately two million pounds of solid fuel per launch the mixture is 70% ammonium perchlorate, 16% aluminum metal, and 14% organic polymer. 

Boron is virtually unknown in the fireworks industry, but is a widely-used fuel in igniter and delay compositions for military and aerospace applications. 

Two basic audible effects are produced by explosive and pyrotechnic devices a loud explosive noise (called a "report" or "salute" in the fireworks industry) and a whistling sound. 

The fireworks industry remains perhaps the most visible example of pyrotechnics, and also remains a major user of traditional black powder. This industry provides the pyrotechnician with the opportunity to fully display his skill at producing colors and other brilliant visual effects. 

Large flakes, called "flitter" aluminum, are widely used by the fireworks industry to produce bright white sparks. A special "pyro" grade of aluminum is also available from some suppliers. This is a dark gray powder consisting of small particle sizes and high surface area and it is extremely reactive. It is used to produce explosive mixtures for fireworks, and combinations of oxidizers with this "pyro" aluminum should only be prepared by skilled personnel, and only made in small batches. Their explosive power can be substantial, and they can be quite sensitive to ignition. 

Several metallic sulfide compounds have been used as fuels in pyrotechnic compositions. Antimony trisulfide, Sb 2S3, is a reasonably low-melting material (m.p. 548°C) with a heat of combustion of approximately 1 kcal/gram. It is easily ignited and can be used to aid in the ignition of more difficult fuels, serving as a "tinder" in the same way that elemental sulfur does. It has been used in the fireworks industry for white fire compositions and has been used in place of sulfur in "flash and sound" mixtures with potassium perchlorate and aluminum. 

Larger particles of charcoal in a pyrotechnic mixture will produce attractive orange sparks in the flame, a property that is often used to advantage by the fireworks industry. 

Dextrine is widely used as a binder in the fireworks industry. Water is used as the wetting agent for dextrine, avoiding the cost associated with the use of organic solvents. 

Whistles, Pyrotechnic. US projectile ground-burst and booby-trap flash simulators precede their flash and expin with a whistling sound. The fact that certain compns whistle when compressed into a tube and ignited has been used in the fireworks industry for many years. The active substance most often used in pyrot whistles is gallic acid (3,4,5-trihydroxybenzoic acid). The K salts of benzoic acid of 2,4-dinitrophenol and of picric acid (2,4,6-trinitrophenol) and the Na salt of salicylic acid (o-hydroxybenzoic acid) are also effective. They are combined with K chlorate,... 

A useful source of data on the safety record of the transportation of expls is the Office of Hazardous Materials News, Office of the Secretary, Department of Transportation, Washington, DC. A European collection of data on industry connected accidents is said to have been collected by Dr Karl Trautzl (Ref 44). The Department of Defense Explosives Safety Board has issued two series of publications (Ref 26). The first are the proceedings of the Annual Explosives Safety Seminars. The second publication series are the abstracts of expl accidents. These reports are submitted voluntarily by both government and industry and are complete with descriptions of causes, damage and casualties. Incidents related to the Fireworks industry are reported annually in the Fire Journal (Ref 64)... 

Watkins, T., Cackett, J.C. and Hall, R.G., Chemicals, Pyrotechnics and the Fireworks Industry, Oxford Permagon Press (1968). 

Molecular weight 117. 9, colourless rhombic crystals, specific gravity 1.95 and it is the least used of all the oxidizers in the firework industry. It has a transition point-to the tetragonal system at about 2 0 C. It is said that pure ammonium perchlorate sublimes without melting when it is slowly heated in the air, but when we heat the normal commercial material in a porcelain crucible with an electric heater, it decomposes violently at 260 360 C. A sample which was recrystallized four times decomposed at 386 0. From this fact we know that ammonium perchlorate decomposes easily due to the action of some impurities, Cr etc. 

It can be taken as axiomatic that every person in the fireworks industry recognises that they are dealing with potentially dangerous substances and articles, and that in this regard they will strive to reduce the hazard to themselves and the general public to the absolute minimum. 

This book does not claim to be a definitive text on fireworks and the fireworks industry. It is primarily an introduction to the basic science of fireworks with particular emphasis on the underlying chemistry and physics. 

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