Monday, July 4, 2011

Fire Works

Fireworks are a class of explosive pyrotechnic devices used for aesthetic and entertainment purposes. The most common use of a firework is as part of a fireworks display. A fireworks event (also called a fireworks show or pyrotechnics) is a display of the effects produced by firework devices. Fireworks competitions are also regularly held at a number of places. Fireworks (devices) 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 including red, orange, yellow, green, blue, purple, and silver. Displays are common throughout the world and are the focal point of many cultural and religious celebrations.
Fireworks were invented in China in the 7th century to scare away evil spirits, as a natural extension of one of the Four Great Inventions of ancient China, gunpowder. Such important events and festivities as Chinese New Year and the Mid-Autumn Moon Festival were and still are times when fireworks are guaranteed sights. China is the largest manufacturer and exporter of fireworks in the world.
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 colored. The skyrocket is a common form of firework, although the first skyrockets were used in war. Such rocket technology has also been used for the delivery of mail by rocket and is used as propulsion for most model rockets. 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.
Ground fireworks, although less popular than aerial ones, create a stunning exhibition. These types of fireworks can produce various shapes, ranging from simple rotating circles, stars and 3D globes.

History
The earliest documentation of fireworks dates back to 7th century China where they were first used to frighten away evil spirits with their loud sound (鞭炮/鞭砲 biān pào) and to pray for happiness and prosperity. Chinese children grow up with folk stories about one-footed monsters who could be scared away by roasting bamboo for the purpose of producing a loud bang.
Eventually the art and science of firework making developed into an independent profession. In ancient China, pyrotechnicians (firework-masters) were respected for their knowledge and skill in mounting dazzling displays of light and sound. A record in 1264 states that the speed of the rocket-propelled 'ground-rat' firework frightened the Empress Dowager Gong Sheng during a feast held in her honor by her son Emperor Lizong of Song (r. 1224–1264). By the 14th century rocket propulsion was common in warfare, as evidenced by the Huolongjing compiled by Liu Ji (1311–1375) and Jiao Yu (fl. c. 1350–1412).
However, in China, fireworks for ceremonies and celebrations were mostly for royalties and the rich before the 14th century. It was only in the Ming Dynasty that any event for common people — a birth, a wedding, a business opening, or a New Year's Eve celebration — became a fitting occasion for fireworks and other noisemakers.
Amédée-François Frézier published a "Treatise on Fireworks" in 1706, covering the recreational and ceremonial uses of fireworks, rather than their military uses. The book became a standard text for fireworks makers.
Music for the Royal Fireworks was composed by George Frideric Handel in 1749 to celebrate the peace Treaty of Aix-la-Chapelle, which had been declared the previous year.

safety
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 fires after landing on flammable material. For this reason, the use of fireworks is generally legally restricted. Display fireworks are restricted by law for use by professionals; consumer items, available to the public, are smaller versions containing limited amounts of explosive material to reduce potential danger. Fireworks may pose a problem for animals, both domestic and wild, who can be terrified by the noise, leading to them running away or hurting themselves on fences or in other ways in an attempt to escape.

Competitions

Main article: Fireworks competitions
Pyrotechnical competitions involving fireworks are held in many countries. One of the most prestigious fireworks competition is the Montreal Fireworks Festival, an annual competition held in Montreal, Quebec, Canada. Another magnificent competition is Le Festival d’Art Pyrotechnique held in the summer annually at the Bay of Cannes in Côte d'Azur, France. The World Pyro Olympics is an annual competition amongst the top fireworks companies in the world. It is held in Manila, Philippines. The event is one of the largest and most intense international fireworks competitions.
Fireworks world records

The current Guinness World Records as of 5 November 2007 are
Largest Catherine wheel
A self-propelled vertical firework wheel 25.95 m (85 ft) in diameter was designed by the Newick Bonfire Society Ltd and fired for at least one revolution on 30 October 1999 at the Village Green, Newick, East Sussex, UK. The Lily Fireworks Factory, Mqabba, Malta currently possess this record, burning a Catherine Wheel with a diameter of 32 metres, on June 18th, 2011.

Largest firework display
The record for the largest firework display consisted of 66,326 fireworks and was achieved by Macedo'S Pirotecnia Lda. in Funchal, Madeira, Portugal, on 31 December 2006.

Longest firework waterfall
The world's longest firework waterfall was the 'Niagara Falls', which measured 3,125.79 m (10,255 ft 2.5 in) when ignited on 24 August 2003 at the Ariake Seas Fireworks Festival, Fukuoka, Japan.

Most firework rockets launched in 30 seconds
The record for the most firework rockets launched in 30 seconds is 56,405, in an attempt organized by Dr Roy Lowry (UK), executed by Fantastic Fireworks, at the 10th British Firework Championship in Plymouth, UK, on 16 August 2006.
Largest bonfire

The largest bonfire had an overall volume of 1,401.6 m³ (49,497 ft³). The bonfire was built by Colin Furze (UK) in Thistleton, Leicestershire, UK, and lit on 14 October 2006.

Tallest bonfire
The world's tallest bonfire tondo measured 37.5 m (123 ft) high, with a base of 8 m² (86 ft²) and an overall volume of 800 m³ (28,251 ft³). The event was organized by Kure Commemorative Centennial Events Committee, and lit on 9 February 2003 at Gohara-cho, Hiroshima, Japan, as part of a traditional ceremony to encourage good health and a generous harvest.

New explosives classes
The U.S. government now uses the United Nations explosives shipping classification system. This new system is based on hazard in shipping only, vs. the old USA system of both shipping and use hazards. The BATF and most states performed a direct substitution of Shipping Class 1.3 for Class B, and Shipping Class 1.4 for Class C. This allows some hazardous items that would have previously been classified as Class B and regulated to be classified as Shipping Class 1.4 due to some packaging method that confines any explosion to the package. Being Shipping Class 1.4, they can now be sold to the general public and are unregulated by the BATF.
A code number and suffix (such as 1.3G) is not enough to fully describe a material and how it is regulated, especially in Shipping Class 1.4G. It also must have a UN Number that exactly describes the material. For example, common consumer fireworks are UN0336, or Shipping Class 1.4G UN0336.
Here are some common fireworks classes:
Class 1.1G (Mass Explosion Possible:Pyrotechnics) UN0094 Flashpowder
Class 1.1G (Mass Explosion Possible:Pyrotechnics) UN0333 Fireworks (Salutes in bulk or in manufacture)
Class 1.2G (Projection but not mass explosion:Pyrotechnics) UN0334 Fireworks (Rarely used)
Class 1.3G (Fire, Minor Blast:Pyrotechnics) UN0335 Fireworks (Most Display Fireworks) Current federal law states that without appropriate ATF license/permit, the possession or sale of any display/professional fireworks is a felony punishable by up to 5 years in prison.
Any ground salute device with over 50 milligrams of explosive composition
Torpedoes (except for railroad signaling use)
Multi-tube devices containing over 500 grams of pyrotechnic composition and without 1/2" space between each tube
Any multiple tube fountains with over 500 grams of pyrotechnic composition and without 1/2" space between each tube
Any reloadable aerial shells over 1.75" diameter
Display shells
Any single-shot or reloadable aerial shell/mine/comet/tube with over 60 grams of pyrotechnic composition
Any Roman candle or rocket with over 20 grams of pyrotechnic composition
Any aerial salute with over 130 milligrams of explosive composition
Class 1.4G (Minor Explosion Hazard Confined To Package:Pyrotechnics) UN0336 Fireworks (Consumer or Common Fireworks) Most popular consumer fireworks sold in the US.
Reloadable aerial shells 1.75" or less sold in a box with not more than 12 shells and one launching tube
Single-shot aerial tubes
Bottle rockets
Skyrockets and missiles
Ground spinners, pinwheels and helicopters
Flares & fountains
Roman candles
Smoke and novelty items
Multi-shot aerial devices, or "cakes"
Firecracker packs (see this link for various brand/label images). Although some firecracker items may be called "M-80's", "M-1000's", "Cherry bombs" or "Silver Salutes" by the manufacturer, they must contain less than 50 milligrams of flash or other explosive powder in order to be legally sold to consumers in the United States.
Sparklers
Catherine wheel
black snakes and strobes
Mines
Class 1.4S (Minor Explosion Hazard Confined To Package: Packed As To Not Hinder Nearby Firefighters) UN0336 Fireworks (Consumer or Common Fireworks)
Class 1.4G (Minor Explosion Hazard Confined To Package:Pyrotechnics) UN0431 ARTICLES, PYROTECHNIC for technical purposes (Proximate Pyrotechnics)
Class 1.4S (Minor Explosion Hazard Confined To Package: Packed As To Not Hinder Nearby Firefighters) UN0432 ARTICLES, PYROTECHNIC for technical purposes (Proximate Pyrotechnics)
Fireworks tubes are made by rolling thick paper tightly around a former, such as a dowel. They can be made by hand, most firework factories use machinery to manufacture tubes. Whenever tubes are used in fireworks, at least one end is always plugged with clay to keep both chemicals and burning gases from escaping through that end. The tooling is always made of non-sparking materials such as aluminium or brass. Experts at handling explosives, called pyrotechnicians, add chemicals for special effects.

Pyrotechnic compounds
Colors in fireworks are usually generated by pyrotechnic stars—usually just called stars—which produce intense light when ignited. Stars contain five basic types of ingredients.
A fuel which allows the star to burn
An oxidizer—a compound which produces (usually) oxygen to support the combustion of the fuel
Color-producing chemicals
A binder which holds the pellet together.
A chlorine donor which provides chlorine to strengthen the color of the flame. Sometimes the oxidizer can serve this purpose.
Some of the more common color-producing compounds are tabulated here. The color of a compound in a firework will be the same as its color in a flame test (shown at right). Not all compounds that produce a colored flame are appropriate for coloring fireworks, however. Ideal colorants will produce a pure, intense color when present in moderate concentration.