Science Fair Project Encyclopedia
- This article is about the explosive device. For the bitmap/vector drawing software, see Macromedia Fireworks
Fireworks are classified as low explosive devices and form a distinct variety of pyrotechnics, whose definition also generally includes devices for military and industrial use. Fireworks are primarily for aesthetic and entertainment purposes. They take many forms to produce the four primary effects: noise, light, smoke, and floating materials (confetti for example). They may be designed to burn with colored flames and sparks. Displays are common throughout the world and are the focal point of many different cultural and religious celebrations.
Fireworks are generally classified as to where they perform, either as a ground or aerial firework. In the latter case they may provide their own propulsion (skyrocket) or be shot into the air by a mortar (aerial shell ).
The most common feature of fireworks is a paper or pasteboard tube or casing filled with the combustible material, often pyrotechnic stars . A number of these tubes or cases are often combined so as to make, when kindled, a great variety of sparkling shapes, often variously coloured. The skyrocket is a common form of firework, however, the first skyrockets were used in war. The aerial shell is the backbone of today's commercial aerial display, a smaller version for consumer use is known as the festival ball in the United States.
Improper use of fireworks may be dangerous, both to the person operating them (risks of burns and wounds) and to bystanders; in addition, they may start a fire if landing on flammable material. For this reason, the use of fireworks is generally legally restricted. In the United States, fireworks are classified as either consumer or display fireworks based upon the amount of pyrotechnic compostion an item contains. Display fireworks are restricted by law for use by professionals. Consumer items are available to the public and are smaller versions containing limited amounts of material to reduce potential dangers.
History of fireworks
In the Han Dynasty (206–220 BC) firecrackers were made by roasting bamboo to produce the loud sound (known as "bian pao") that was intended to frighten evil spirits. In the Northern and Southern Dynasties (AD 420–581) the firecrackers were used not only used to dispel evil but also to pray for happiness and prosperity.
The discovery of gunpowder and the invention of the first true fireworks are traditionally credited to the Chinese, although India is also a likely source. Some scholars believe fireworks were developed in the Sui and Tang Dynasties (581–907), but others believe there were no fireworks until the Northern Song Dynasty (10th century).
America's earliest settlers brought their enthusiasm for fireworks to the United States. Fireworks and black powder were used to celebrate important events long before the American Revolutionary War. The very first celebrations of Independence Day were in 1777, six years before Americans knew whether the new nation would survive the war; fireworks were a part of those festivities. In 1789, George Washington's inauguration was also accompanied by a fireworks display. This early fascination with their noise and color continues today.
In 2004, Disneyland in Anaheim, California, started using air burst fireworks launched with compressed air rather than black powder, the first time that such a launch system was used commercially. The display charge is detonated using an electronic timer. The advantages of compressed air launch are a reduction in fumes, and much greater accuracy in height and timing.
Bonfire night in Britain
In 1605 Guy Fawkes and his fellow conspirators attempted to blow up the British Parliament with 36 barrels of gunpowder in the cellars of Westminster Hall. On 5 November, Fawkes was arrested and Parliament was saved. That night is now celebrated as bonfire night by filling the sky with exploding fireworks, and by burning an effigy of Guy Fawkes on a bonfire.
- Remember, remember the fifth of November.
- Gunpowder, treason and plot.
- I see no reason why gunpowder treason
- Should ever be forgot.
- – a children's rhyme about the events, still spoken today
Licensing for firework sellers has recently been introduced in the United Kingdom. Fireworks cannot be sold to people under the age of 18 and setting them off between 11pm and 7am is only allowed at specific times of the year, including New Year and Bonfire night.
Independence Day in the United States
Each year before the American Independence Day, the Fourth of July, retail fireworks stands spring up around the nation in states that do not severely restrict or outright ban all fireworks for safety reasons (such as Nevada). Popular types of legal use-at-home fireworks include:
- Roman candles
- Fountain batteries
- "Snakes" (turn to ash)
- Saturn missile batteries
- Smoke bombs (not an actual explosive)
Note that South Carolina sells slightly more explosive fireworks in addition to these popular types; these are usually referred to as "firecrackers". Interestingly, South Carolina also sells fireworks at stands year-round.
Because of the hodge-podge of different regulations in the various U.S. states, many towns at or near state borders set up shop in order to attract customers from areas where fireworks are restricted. A similar situation can happen with Native American tribes that have reservation lands. They often sell firecrackers that are not legal for sale outside of the reservation. Such firecracker types include, but are not limited to:
- Cherry bombs
- M-80 firecrackers
- M-100 firecrackers
- M-1000 firecrackers
- "Black cat" rolls
- Mortar tubes
- Bottle rockets
Note that actual ownership or sale of true cherry bombs, M-80 style salutes, or any firecracker in excess of 50 milligrams of powder is a violation of federal law (1966 Child Protection Act). Native Americans, like any other U.S. citizen, are not exempt from federal law. However, 50 mg of powder is likely more than is used even in the most powerful firecrackers.
New Year's Eve in Western Europe
Although it is now just a custom to fire off fireworks on New-Year's eve, in the past the idea was to scare 'bad forces' so they would not enter the new year. As a consequence the most popular fireworks are still those that go off with a big bang or with a bright flash.
The retail of fireworks in Western Europe is also restricted, but the limitations differ from country to country. In the Netherlands for example the sale of fireworks is restricted to a few days before New-Year's eve, but in Belgium the sale of fireworks is legal throughout the year. Also the fireworks sold in Belgium contain more gunpowder than is allowed in the Netherlands. This leads to some illegal trafficking of fireworks from Belgium to the Netherlands.
- How Fireworks work
- The Pyrotechnics Guild International, an independent worldwide nonprofit organization of amateur and professional fireworks enthusiasts.
- Illegal Explosive Devices
- About.com The Chemistry of Firework Colors
- What is a M-80? And why can't you buy one?
- Pyrotechnic Glossary
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