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Wednesday, November 1, 2023

Fireworks

From Wikipedia, the free encyclopedia
https://en.wikipedia.org/wiki/Fireworks

Fireworks
Fireworks over Sydney Harbour on New Year's Eve 2006–2007
 
Bastille Day fireworks (2013) over Paris, traditionally accompanied by a musical show that starts with "La Marseillaise"
 
A fireworks display on Taipei 101, Taiwan, which in 2005 held the world's first fireworks display on a supertall skyscraper

Fireworks on Qatar National Day 2018 in Doha

Fireworks are a class of low explosive pyrotechnic devices used for aesthetic and entertainment purposes. They are most commonly used in fireworks displays (also called a fireworks show or pyrotechnics), combining a large number of devices in an outdoor setting. Such displays are the focal point of many cultural and religious celebrations, though mismanagement could lead to fireworks accidents.

Fireworks take many forms to produce four primary effects: noise, light, smoke, and floating materials (confetti most notably). They may be designed to burn with colored flames and sparks including red, orange, yellow, green, blue, purple and silver. They are generally classified by where they perform, either 'ground' or 'aerial'. Aerial fireworks may have their own propulsion (skyrocket) or be shot into the air by a mortar (aerial shell).

Most fireworks consist of a paper or pasteboard tube or casing filled with the combustible material, often pyrotechnic stars. A number of these tubes or cases may be combined so as to make when kindled, a great variety of sparkling shapes, often variously colored. A skyrocket is a common form of firework, although the first skyrockets were used in warfare. The aerial shell, however, is the backbone of today's commercial aerial display, and a smaller version for consumer use is known as the festival ball in the United States.

Fireworks were originally invented in China. China remains the largest manufacturer and exporter of fireworks in the world.

'Silent' fireworks displays are becoming popular due to concerns that noise effects traumatize pets, wildlife, and some humans. However these are not a new type of firework and they are not completely silent. "Silent firework displays" refers to displays which simply exclude large, spectacular, noisy fireworks and make greater use of smaller, quieter devices. The Italian town of Collecchio switched to silent fireworks in 2015.

History

An illustration of a fireworks display from the 1628–1643 edition of the Ming Dynasty novel Jin Ping Mei
An etching of the Royal Fireworks display on the Thames, London, England, in 1749
An 18th-century illustration of Chinese fireworks from an English abstract of an account of China by French Jesuit Pierre Nicolas d'Incarville
A firework display for Muḥammad Sháh, portrayed seated and leaning against a bolster
Preparing fireworks at Sayn Castle, Germany
Two ignited Catherine wheels spinning during a traditional Maltese feast
A ground firework showing various technical parts mentioned in the article, such as the chain and a set of gears
The grand finale showing also the jets that produce power. A picture taken from the back so the stars and flowers are not so clearly visible

The earliest fireworks came from China during the Song dynasty (960–1279). Fireworks were used to accompany many festivities. In China, pyrotechnicians were a much respected profession.

During the Han dynasty (202 BC – 220 AD), people threw bamboo stems into a fire to produce an explosion with a loud sound. In later times, gunpowder packed into small containers was used to mimic the sounds of burning bamboo. Exploding bamboo stems and gunpowder firecrackers were interchangeably known as baozhu (爆竹) or baogan (爆竿). It was during the Song dynasty that people manufactured the first firecrackers comprising tubes made from rolled sheets of paper containing gunpowder and a fuse. They also strung these firecrackers together into large clusters, known as bian (lit. "whip") or bianpao (lit. "whip cannon"), so the firecrackers could be set off one by one in close sequence. By the 12th and possibly the 11th century, the term baozhang (爆仗) was used to specifically refer to gunpowder firecrackers.

During the Song dynasty, many of the common people could purchase various kinds of fireworks from market vendors. Grand displays of fireworks were also known to be held. In 1110, a large fireworks display in a martial demonstration was held to entertain Emperor Huizong of Song (r. 1100–1125) and his court. A record from 1264 states that a rocket-propelled firework went off near the Empress Dowager Gong Sheng and startled her during a feast held in her honor by her son Emperor Lizong of Song (r. 1224–1264). Rocket propulsion was common in warfare, as evidenced by the Huolongjing compiled by Liu Bowen (1311–1375) and Jiao Yu (fl. c. 1350–1412). In 1240 the Arabs acquired knowledge of gunpowder and its uses from China. A Syrian named Hasan al-Rammah wrote of rockets, fireworks, and other incendiaries, using terms that suggested he derived his knowledge from Chinese sources, such as his references to fireworks as "Chinese flowers".

Colored fireworks were developed from earlier (possibly Han dynasty or soon thereafter) Chinese application of chemical substances to create colored smoke and fire. Such application appears in the Huolongjing (14th century) and Wubeizhi (preface of 1621, printed 1628), which describes recipes, several of which used low-nitrate gunpowder, to create military signal smokes with various colors. In the Wubei Huolongjing (武備火龍經; Ming, completed after 1628), two formulas appears for firework-like signals, the sanzhangju (三丈菊) and baizhanglian (百丈蓮), that produces silver sparkles in the smoke. In the Huoxilüe (火戲略; 1753) by Zhao Xuemin (趙學敏), there are several recipes with low-nitrate gunpowder and other chemical substances to tint flames and smoke. These included, for instance, arsenical sulphide for yellow, copper acetate (verdigris) for green, lead carbonate for lilac-white, and mercurous chloride (calomel) for white. The Chinese pyrotechnics were described by the French author Antoine Caillot (1818): "It is certain that the variety of colours which the Chinese have the secret of giving to flame is the greatest mystery of their fireworks." Similarly, the English geographer Sir John Barrow (ca. 1797) wrote "The diversity of colours indeed with which the Chinese have the secret of cloathing fire seems to be the chief merit of their pyrotechny."

Fireworks were produced in Europe by the 14th century, becoming popular by the 17th century. Lev Izmailov, ambassador of Peter the Great, once reported from China: "They make such fireworks that no one in Europe has ever seen." In 1758, the Jesuit missionary Pierre Nicolas le Chéron d'Incarville, living in Beijing, wrote about the methods and composition of Chinese fireworks to the Paris Academy of Sciences, which published the account five years later. Amédée-François Frézier published his revised work Traité des feux d'artice pour le spectacle (Treatise on Fireworks) in 1747 (originally 1706), covering the recreational and ceremonial uses of fireworks, rather than their military uses. 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.

"Prior to the nineteenth century and the advent of modern chemistry they [fireworks] must have been relatively dull and unexciting." Bertholet in 1786 discovered that oxidations with potassium chlorate resulted in a violet emission. Subsequent developments revealed that oxidations with the chlorates of barium, strontium, copper, and sodium result in intense emission of bright colors. The isolation of metallic magnesium and aluminium marked another breakthrough as these metals burn with an intense silvery light.

Safety and environmental impact

A firework rocket preparing its launch on the American Independence Day
New Year fireworks

Improper use of fireworks is dangerous, both to the person operating them (risks of burns and wounds) and to bystanders; in addition, they may start fires on landing. To prevent fireworks accidents, the use of fireworks is legally restricted in many countries. In such countries, display fireworks are restricted for use by professionals; smaller consumer versions may or may not be available to the public.

Birds and animals, both domestic and wild, can be frightened by their noise, leading to them running away, often into danger, or hurting themselves on fences or in other ways in an attempt to escape the perceived danger. Frightened birds also may abandon nests and not return to complete rearing their young.

Pollution

Haze caused by smoke from fireworks, combined with smoke from wildfires few miles away from where the photo was taken

Fireworks produce smoke and dust that may contain residues of heavy metals, sulfur-coal compounds and some low concentration toxic chemicals. These by-products of fireworks combustion will vary depending on the mix of ingredients of a particular firework. (The color green, for instance, may be produced by adding the various compounds and salts of barium, some of which are toxic, and some of which are not.) Some fishers have noticed and reported to environmental authorities that firework residues can hurt fish and other water-life because some may contain toxic compounds (such as antimony sulfide or arsenic). This is a subject of much debate due to the fact that large-scale pollution from other sources makes it difficult to measure the amount of pollution that comes specifically from fireworks. The possible toxicity of any fallout may also be affected by the amount of black powder used, type of oxidizer, colors produced and launch method.

Perchlorate salts, when in solid form, dissolve and move rapidly in groundwater and surface water. Even in low concentrations in drinking water supplies, perchlorate ions are known to inhibit the uptake of iodine by the thyroid gland. As of 2010, there are no federal drinking water standards for perchlorates in the United States, but the US Environmental Protection Agency has studied the impacts of perchlorates on the environment as well as drinking water.

Several U.S. states have enacted drinking water standard for perchlorates, including Massachusetts in 2006. California's legislature enacted AB 826, the Perchlorate Contamination Prevention Act of 2003, requiring California's Department of Toxic Substance Control (DTSC) to adopt regulations specifying best management practices for perchlorate-containing substances. The Perchlorate Best Management Practices were adopted on 31 December 2005 and became operative on 1 July 2006. California issued drinking water standards in 2007. Several other states, including Arizona, Maryland, Nevada, New Mexico, New York, and Texas have established non-enforceable, advisory levels for perchlorates.

The courts have also taken action with regard to perchlorate contamination. For example, in 2003, a federal district court in California found that Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) applied because perchlorate is ignitable and therefore a "characteristic" hazardous waste.

Pollutants from fireworks raise concerns because of potential health risks associated with the products of combustion during the liquid phase and the solid phase after they have cooled as well as the gases produced, particularly the carbon monoxide and carbon dioxide. For persons with asthma or multiple chemical sensitivity the smoke from fireworks may aggravate existing health problems.

Pollution is also a concern because fireworks often contain heavy metals as source of color. However, gunpowder smoke and the solid residues are basic, and as such the cumulative effect of fireworks on acid rain is uncertain. What is not disputed is that most consumer fireworks leave behind a considerable amount of solid debris, including both readily biodegradable components as well as nondegradable plastic items. Concerns over pollution, consumer safety, and debris have restricted the sale and use of consumer fireworks in many countries. Professional displays, on the other hand, remain popular around the world.

Others argue that alleged concern over pollution from fireworks constitutes a red herring, since the amount of contamination from fireworks is minuscule in comparison to emissions from sources such as the burning of fossil fuels. In the US, some states and local governments restrict the use of fireworks in accordance with the Clean Air Act which allows laws relating to the prevention and control of outdoor air pollution to be enacted.

Some companies within the U.S. fireworks industry claim they are working with Chinese manufacturers to reduce and ultimately hope to eliminate of the pollutant perchlorate.

Government regulations around the world

Australia

Fireworks at Australia Day 2013 in Perth

Fireworks are illegal in most Australian states and territories, unless part of a display by a licensed pyrotechnician and with a permit. However Tasmania, ACT and Northern Territory allow consumer use with a permit (dependent on calendar date and circumstances). On 1 July for Territory Day one can freely use fireworks without a permit in the Northern Territory.

Small novelties such as party poppers and sparklers are legal for consumers across Australia.

On 24 August 2009, the ACT Government announced a complete ban on backyard fireworks.

Canada

Canada Day 2016 firework show

The use, storage and sale of commercial-grade fireworks in Canada is licensed by Natural Resources Canada's Explosive Regulatory Division (ERD). Unlike their consumer counterpart, commercial-grade fireworks function differently, and come in a wide range of sizes from 50 mm (2 inches) up to 300 mm (11+1316 inches) or more in diameter. Commercial grade fireworks require a Fireworks Operator Certificate (FOC), obtained from the ERD by completing a one-day safety course. There are two categories of FOC: one for pyrotechnics (those used on stage and in movies) and another for display fireworks (those used in dedicated fireworks shows). Each requires completion of its own course, although there are special categories of FOC which allow visiting operators to run their shows with the assistance of a Canadian supervisor.

The display fireworks FOC has two levels: assistant (which allows you to work under a qualified supervisor until you are familiar with the basics), and fully licensed. A fully licensed display fireworks operator can also be further endorsed for marine launch, flying saucers, and other more technically demanding fireworks displays.

The pyrotechnician FOC has three levels: pyrotechnician (which allows work under a supervisor), supervising pyrotechnician, and special effects pyrotechnician (which allows the fabrication of certain types of pyrotechnic devices). Additionally, a special effects pyrotechnician can be endorsed for the use of detonating cord.

Since commercial-grade fireworks are shells which are loaded into separate mortars by hand, there is danger in every stage of the setup. Setup of these fireworks involves the placement and securing of mortars on wooden or wire racks; loading of the shells; and if electronically firing, wiring and testing. The mortars are generally made of FRE (fiber-reinforced epoxy) or HDPE (high-density polyethylene). Older mortars made of sheet steel have been banned by most countries due to the problem of shrapnel produced during a misfire.

Setup of mortars in Canada for an oblong firing site require that a mortar be configured at an angle of 10 to 15 degrees down-range with a safety distance of at least 200 meters (660 ft) down-range and 100 meters (330 ft) surrounding the mortars, plus distance adjustments for wind speed and direction. In June 2007, the ERD approved circular firing sites for use with vertically fired mortars with a safety distance of at least 175-meter (574 ft) radius, plus distance adjustments for wind speed and direction.

Loading of shells is a delicate process, and must be done with caution, and a loader must ensure not only the mortar is clean, but also make sure that no part of their body is directly over the mortar in case of a premature fire. Wiring the shells is a painstaking process; whether the shells are being fired manually or electronically, any "chain fusing" or wiring of electrical ignitors, care must be taken to prevent the fuse (an electrical match, often incorrectly called a squib) from igniting. If the setup is wired electrically, the electrical matches are usually plugged into a "firing rail" or "breakout box" that runs back to the main firing board; from there, the Firing Board is simply hooked up to a car battery, and can proceed with firing the show when ready.

Since commercial-grade fireworks are so much larger and more powerful, setup, and firing crews are always under great pressure to ensure they safely set up, fire, and clean up after a show.

Chile

In Chile, the manufacture, importation, possession and use of fireworks is prohibited to unauthorized individuals; only certified firework companies can legally use fireworks. As they are considered a type of explosive, offenders can in principle be tried before military courts, although this is unusual in practice.

China

European Union

Fireworks at Eurockéennes 2013 in Belfort, France

The European Union's policy is aimed at harmonising and standardising the EU member states' policies on the regulation of production, transportation, sale, consumption and overall safety of fireworks across Europe.

Belgium

In Belgium, each municipality can decide how to regulate fireworks. During New Year's Eve, lighting fireworks without a licence is allowed in 35% of the 308 Flemish municipalities, in around 50% a permit from the burgemeester (mayor) is required, and around 14% of municipalities have banned consumer fireworks altogether.

Finland

Fireworks on 30 August 2014, in Tampere, Finland

In Finland those under 18 years old haven't been allowed to buy any fireworks since 2009. Safety goggles are required. The use of fireworks is generally allowed on the evening and night of New Year's Eve, 31 December. In some municipalities of Western Finland it is allowed to use fireworks without a fire station's permission on the last weekend of August. With the fire station's permission, fireworks can be used year-round.

Germany

In Germany, amateurs over 18 years old are allowed to buy and ignite fireworks of Category F2 for several hours on 31 December and 1 January; each German municipality is authorised to limit the number of hours this may last locally. The sale of Category F3 and F4 fireworks to consumers is prohibited. Lighting fireworks is forbidden near churches, hospitals, retirement homes and wooden or thatch-roofed buildings. All major German cities organise professional fireworks shows.

In addition to the previously existing regulations, there was a nationwide ban on the sale of category F2 fireworks to consumers on New Year's Eve 2020/2021 during the COVID-19 pandemic, with the aim to relieve the burden on hospitals by reducing the number of emergencies due to injuries caused by fireworks on New Year's Eve.

Italy

In 2015, the Italian town of Collecchio mandated silent fireworks, being among the first to make the switch without losing the beauty of the visual displays.

Netherlands

In the Netherlands, fireworks cannot be sold to anyone under the age of 16. It may only be sold during a period of three days before a new year. If one of these days is a Sunday, that day is excluded from sale and sale may commence one day earlier.

Republic of Ireland

In the Republic of Ireland, fireworks are illegal and possession is punishable by huge fines and/or prison. However, around Halloween a large amount of fireworks are set off, due to the ease of being able to purchase from Northern Ireland.

Sweden

In Sweden, fireworks can only be purchased and used by people 18 or older. Fire crackers used to be banned, but are now allowed under European Union fireworks policy.

Iceland

In Iceland, the Icelandic law states that anyone may purchase and use fireworks during a certain period around New Year's Eve. Most places that sell fireworks in Iceland make their own rules about age of buyers, usually it is around 16. The people of Reykjavík spend enormous sums of money on fireworks, most of which are fired as midnight approaches on 31 December. As a result, every New Year's Eve the city is lit up with fireworks displays.

New Zealand

Fireworks in New Zealand are available from 2 to 5 November, around Guy Fawkes Day, and may be purchased only by those 18 years of age and older (up from 14 years pre-2007). Despite the restriction on when fireworks may be sold, there is no restriction regarding when fireworks may be used. The types of fireworks available to the public are multi-shot "cakes", Roman candles, single shot shooters, ground and wall spinners, fountains, cones, sparklers, and various novelties, such as smoke bombs and Pharaoh's serpents. Consumer fireworks are also not allowed to be louder than 90 decibels.

Norway

In Norway, fireworks can only be purchased and used by people 18 or older. Sale is restricted to a few days before New Year's Eve. Rockets are not allowed.

United Kingdom

Firework display at the Jodrell Bank Observatory 2013

Fireworks in the UK have become more strictly regulated since 1997. Since 2005, the law has been harmonised gradually, in accordance with other EU member state laws.

Fireworks are mostly used in England, Scotland and Wales around Diwali (late October or early November), on Guy Fawkes Night, 5 November and on New Year's Eve. In the UK, responsibility for the safety of firework displays is shared between the Health and Safety Executive, fire brigades and local authorities. Currently, there is no national system of licensing for fireworks operators, but in order to purchase large display fireworks, operators must have licensed explosives storage and public liability insurance.

Fireworks cannot be sold to people under the age of 18 and are not permitted to be set off between 11pm and 7am with exceptions only for:

The maximum legal NEC (net explosive content) of a UK firework available to the public is two kilograms. Jumping jacks, strings of firecrackers, shell firing tubes, bangers and mini-rockets were all banned during the late 1990s. In 2004, single-shot air bombs and bottle rockets were banned, and rocket sizes were limited. From March 2008 any firework with more than 5% flashpowder per tube has been classified 1.3G. The aim of these measures was to eliminate "pocket money" fireworks, and to limit the disruptive effects of loud bangs.

United States

In the United States, fireworks laws vary widely from state to state or county to county. Federal, state, and local authorities govern the use of display fireworks in the United States. The Consumer Product Safety Commission (CPSC) regulates consumer fireworks at the federal level through the Federal Hazardous Substances Act (FHSA). The National Fire Protection Association (NFPA) sets forth a set of codes that give the minimum standards of display fireworks use and safety in the U.S. Both state and local jurisdictions can further add restrictions on the use and safety requirements of display fireworks. There are currently 46 states in the United States in which fireworks are legal for consumer use.

Independence Day fireworks in San Diego, California

Growth

According to industry data, the purchase of fireworks by American consumers has markedly increased since the onset of the COVID-19 pandemic. In the year preceding the pandemic, the consumer fireworks industry reported sales of approximately $1 billion. However, this figure almost doubled in 2020, reaching $2.3 billion. In contrast, commercial fireworks sales amounted to a smaller figure of $400 million. For context, consumer fireworks revenue was significantly lower at $645 million in 2012, indicating a steady growth trend in the market. Industry projections currently anticipate a further increase, forecasting fireworks sales to reach $3.3 billion by 2028.

Competitions

Pyrotechnical competitions are held in many countries. 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.

Clubs and Organizations

Enthusiasts in the United States have formed clubs which unite hobbyists and professionals. The groups provide safety instruction and organize meetings and private "shoots" at remote premises where members shoot commercial fireworks as well as fire pieces of their own manufacture. Clubs secure permission to fire items otherwise banned by state or local ordinances. Competition among members and between clubs, demonstrating everything from single shells to elaborate displays choreographed to music, are held. One of the oldest clubs is Crackerjacks, Inc., organized in 1976 in the Eastern Seaboard region.

Though based in the US, membership of the Pyrotechnics Guild International, Inc. (PGI) is open to all. Founded in 1969, its annual convention hosts some the world's biggest and best fireworks displays occur. Aside from the nightly firework shows, the highlight of the convention is a unique event where individual classes of hand-built fireworks are competitively judged, ranging from simple fireworks rockets to extremely large and complex aerial shells. Some of the biggest, best, most intricate fireworks displays in the United States take place during the convention week.

Halloween

Canada

Both fireworks and firecrackers are a popular tradition during Halloween in Vancouver.

Ireland

In the Republic of Ireland and Northern Ireland there are many fireworks displays, during Halloween. The sale of fireworks is strongly restricted in the Republic of Ireland, although many illegal fireworks are sold throughout October or smuggled from Northern Ireland. The maximum punishment for possessing fireworks without a licence, or lighting fireworks in a public place, is a €10,000 fine and a five-year prison sentence.

United States

Two firework displays on All Hallows' Eve in the United States are the "Happy Hallowishes" show at Walt Disney World's Magic Kingdom "Mickey's Not-So-Scary Halloween Party" event, which began in 2005, and the "Halloween Screams" at Disneyland Park, which began in 2009.

Fireworks celebrations throughout the world

Australia

In Australia, fireworks displays are frequently used in the celebration of public holidays, particularly New Year's Eve and Australia Day. The most famous is the Sydney New Year's Eve Midnight Fireworks. In the Northern Territory, "Cracker Night" is celebrated every 1 July on Territory Day, where residents are allowed to buy and use fireworks without a permit.

France

A firework display by the British illustrator Ebenezer Landells, possibly the display given by Napoleon III on Queen Victoria's 1855 visit to Paris

In France, fireworks are traditionally displayed on the eve of Bastille day (14 July) to commemorate the French revolution and the storming of the Bastille on that same day in 1789. Every city in France lights up the sky for the occasion with a special mention to Paris that offers a spectacle around the Eiffel Tower.

Hungary

In Hungary fireworks are used on 20 August, which is a national celebration day 

India

Indians throughout the world celebrate with fireworks as part of their popular "festival of lights" (Diwali) in Oct-Nov every year.

Japan

During the summer in Japan, fireworks festivals (花火大会, hanabi taikai) are held nearly every day someplace in the country, numbering more than 200 during August alone. The festivals consist of large fireworks shows, the largest of which use between 100,000 and 120,000 rounds (Tondabayashi, Osaka), and can attract more than 800,000 spectators. Street vendors set up stalls to sell various drinks and staple Japanese food (such as yakisoba, okonomiyaki, takoyaki, kakigōri (shaved ice), and traditionally held festival games, such as kingyo-sukui, or goldfish scooping.

Even today, men and women attend these events wearing the traditional yukata, summer kimono, or jinbei, and gather in large social circles of family or friends to sit picnic-like, eating and drinking, while watching the show.

The first fireworks festival in Japan was held in 1733.

Sumidagawa Fireworks Festival is one of the many being celebrated annually throughout Japan in summer.

Malta

Fireworks have been used in Malta for hundreds of years. When the islands were ruled by the Order of St John, fireworks were used on special occasions such as the election of a new Grand Master, the appointment of a new Pope or the birth of a prince.

Nowadays, fireworks are used in village feasts throughout the summer. The Malta International Fireworks Festival is also held annually.

Monte-Carlo International Fireworks Festival

Pyrotechnics experts from around the world have competed in Monte Carlo, Monaco, since 1966. The festival runs from July to August every year, and the winner returns in 18 November for the fireworks display on the night before the National Day of Monaco. The event is held in Port Hercule, beginning at around 9:30pm every night, depending on the sunset.

Singapore

Singapore Fireworks Festival 2006, 8 August 2006

The Singapore Fireworks Celebrations (previously the Singapore Fireworks Festival) is an annual event held in Singapore as part of its National Day celebrations. The festival features local and foreign teams which launch displays on different nights. While currently non-competitive in nature, the organizer has plans to introduce a competitive element in the future.

The annual festival has grown in magnitude, from 4,000 rounds used in 2004, to 6,000 in 2005, to more than 9,100 in 2006.

South Korea

Busan International Fireworks Festival is one of the most significant fireworks festivals in Asia.

Switzerland

In Switzerland fireworks are often used on 1 August, which is a national celebration day.

United Kingdom

One of the biggest occasions for fireworks in the UK is Guy Fawkes Night held each year on 5 November, to celebrate the foiling of the Catholic Gunpowder Plot on 5 November 1605, an attempt to kill King James I. The Guardian newspaper said in 2008 that Britain's biggest Guy Fawkes night events were:

The main firework celebrations in the UK are by the public who buy from many suppliers.

United States

A long-exposure shot of the finale of the second act of IllumiNations: Reflections of Earth, the former nightly fireworks show at Epcot in Walt Disney World

America's earliest settlers brought their enthusiasm for fireworks to the United States. Fireworks and black ash were used to celebrate important events long before the American Revolutionary War. The very first celebration of Independence Day was in 1777, six years before Americans knew whether or not the new nation would survive the war; fireworks were a part of all festivities. In 1789, George Washington's inauguration was accompanied by a fireworks display. George Marshall was an American naval hero during the War of 1812 and other campaigns. He was a Master Gunner and pyrotechnics specialist who wrote Marshall's Practical Marine Gunnery in 1822. The book outlines chemical formulas for the composition of fireworks. This early fascination with fireworks' noise and color continues today with fireworks displays commonly included in Independence Day celebrations.

In 2004, Disneyland, in Anaheim, California, pioneered the commercial use of aerial fireworks launched with compressed air rather than gunpowder. The display shell explodes in the air using an electronic timer. The advantages of compressed air launch are a reduction in fumes, and much greater accuracy in height and timing. The Walt Disney Company is now the largest consumer of fireworks in the world.

Uses other than public displays

In addition to large public displays, people often buy small quantities of fireworks for their own celebrations. Fireworks on general sale are usually less powerful than professional fireworks. Types include firecrackers, rockets, cakes (multishot aerial fireworks), and smoke balls.

Fireworks can also be used in an agricultural capacity as to frighten away birds.

Pyrotechnic compounds

Copper compounds glow green or blue-green in a flame.
Fireworks shell

Colors in fireworks are usually generated by pyrotechnic stars—usually just called stars—which produce intense light when ignited. Stars contain four basic types of ingredients.

  • A fuel
  • An oxidizer—a compound that combines with the fuel to produce intense heat
  • Color-producing salts (when the fuel itself is not the colorant)
  • A binder which holds the pellet together.

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.

The color of sparks is limited to red/orange, yellow/gold and white/silver. This is explained by light emission from an incandescent solid particle in contrast to the element-specific emission from the vapor phase of a flame. Light emitted from a solid particle is defined by black-body radiation. Low boiling metals can form sparks with an intensively colored glowing shell surrounding the basic particle. This is caused by vapor phase combustion of the metal.

Color Metal Example compounds
Red Strontium (intense red)

Lithium (medium red)

SrCO3 (strontium carbonate)

Li2CO3 (lithium carbonate) LiCl (lithium chloride)

Orange Calcium CaCl2 (calcium chloride)
Yellow Sodium NaNO3 (sodium nitrate)
Green Barium BaCl2 (barium chloride)
Blue Copper halides CuCl2 (copper(II) chloride), at low temperature
Indigo Caesium CsNO3 (caesium nitrate)
Violet Potassium

Rubidium (violet-red)

KNO3 (potassium nitrate)

RbNO3 (rubidium nitrate)

Gold Charcoal, iron, or lampblack
White Titanium, aluminium, or magnesium powders

The brightest stars, often called Mag Stars, are fueled by aluminium. Magnesium is rarely used in the fireworks industry due to its lack of ability to form a protective oxide layer. Often an alloy of both metals called magnalium is used.

Many of the chemicals used in the manufacture of fireworks are non-toxic, while many more have some degree of toxicity, can cause skin sensitivity, or exist in dust form and are thereby inhalation hazards. Still others are poisons if directly ingested or inhaled.

Common elements in pyrotechnics

The following table lists the principal elements used in modern pyrotechnics. Some elements are used in their elemental form such as particles of titanium, aluminium, iron, zirconium, and magnesium. These elements burn in the presence of air (O2) or oxidants (perchlorate, chlorate). Most elements in pyrotechnics are in the form of salts.

Symbol Name Fireworks usage
Al Aluminium Aluminium metal is used to produce silver and white flames and sparks. It is a common component of sparklers.
Ba Barium Barium salts are used to create green colors in fireworks, and it can also help stabilize other volatile elements.
C Carbon Carbon is one of the main components of black powder, which is used as a propellent in fireworks. Carbon provides the fuel for a firework. Common forms include carbon black, sugar, or starch.
Cl Chlorine Chlorate and perchlorates are common oxidizers.
Cu Copper Copper compounds produce blue colors.
Fe Iron Iron powder is used to produce sparks in sparklers.
K Potassium Potassium nitrate, potassium chlorate, and potassium perchlorate are common oxidizers. The potassium content imparts a faint violet color to the sparks.
Mg Magnesium Magnesium metal burns a very bright white, so it is used to add white sparks or improve the overall brilliance of a firework.
Na Sodium Sodium imparts a gold or yellow color to fireworks, however, the color is often so bright that it frequently masks other, less intense colors. Sodium lamps operate with the same optical emission.
O Oxygen Oxygen is a component of chlorate and perchlorate, common oxidizers.
S Sulfur Sulfur is a component of black powder, and as such, it is found in a propellant/fuel.
Sr Strontium Strontium salts impart a red color.
Ti Titanium Titanium metal can be burned as powder or flakes to produce silver sparks.
Zr Zirconium Zirconium, like titanium, burns to produce oxides that emit brightly. It is used in "waterfalls".

Types of effects

Cake

A cake is a cluster of individual tubes linked by fuse that fires a series of aerial effects. Tube diameters can range in size from 14–4 inches (6.4–101.6 mm), and a single cake can have more than 1,000 shots. The variety of effects within individual cakes is often such that they defy descriptive titles and are instead given cryptic names such as "Bermuda Triangle", "Pyro Glyphics", "Waco Wakeup", and "Poisonous Spider", to name a few. Others are simply quantities of 2.5–4 in (64–102 mm) shells fused together in single-shot tubes.

Crossette

A shell containing several large stars that travel a short distance before breaking apart into smaller stars, creating a crisscrossing grid-like effect. Strictly speaking, a crossette star should split into four pieces which fly off symmetrically, making a cross. Once limited to silver or gold effects, colored crossettes such as red, green, or white are now very common.

Chrysanthemum

Chrysanthemum shells in New York

A spherical break of colored stars, similar to a peony, but with stars that leave a visible trail of sparks.

Dahlia

Essentially the same as a peony shell, but with fewer and larger stars. These stars travel a longer-than-usual distance from the shell break before burning out. For instance, if a 3 in (76 mm) peony shell is made with a star size designed for a 6 in (152 mm) shell, it is then considered a dahlia. Some dahlia shells are cylindrical rather than spherical to allow for larger stars.

Diadem

A type of chrysanthemum or peony, with a center cluster of non-moving stars, normally of a contrasting color or effect.

Fish

Inserts that propel themselves rapidly away from the shell burst, often resembling fish swimming away.

Horsetail

Named for the shape of its break, this shell features heavy long-burning tailed stars that only travel a short distance from the shell burst before free-falling to the ground. Also known as a waterfall shell. Sometimes there is a glittering through the "waterfall".

Kamuro

A typical kamuro effect

Kamuro is a Japanese word meaning "boys haircut", which is what this shell resembles when fully exploded in the air. It is a dense burst of glittering silver or gold stars which leave a heavy glitter trail and shine bright in the night's sky.

Mine

A mine (a.k.a. pot à feu) is a ground firework that expels stars and/or other garnitures into the sky. Shot from a mortar like a shell, a mine consists of a canister with the lift charge on the bottom with the effects placed on top. Mines can project small reports, serpents, and small shells, as well as just stars. Although mines up to 12 inches (305 mm) diameter appear on occasion, they are usually 3–5 inches (76–127 mm) in diameter.

Multi-break shells

A large shell containing several smaller shells of various sizes and types. The initial burst scatters the shells across the sky before they explode. Also called a bouquet shell. When a shell contains smaller shells of the same size and type, the effect is usually referred to as "Thousands". Very large bouquet shells (up to 48 inches [1,219 mm]) are frequently used in Japan.

Noise-related effects

  • Bang
    The bang is the most common effect in fireworks and sounds like artillery cannon being fired; technically a "report". Silent fireworks have all of the visual effects, however. The "salute" effect is even more pronounced and sometimes is banned.
  • Crackle
    The firework produces a crackling sound.
  • Hummer
    Tiny tube fireworks that are ejected into the air spinning with such force that they shred their outer coating, in doing so they whizz and hum.
  • Whistle
    High pitched often very loud screaming and screeching created by the resonance of gas. This is caused by a very fast strobing (on/off burning stage) of the fuel. The rapid bursts of gas from the fuel vibrate the air many hundreds of times per second causing the familiar whistling sound. It is not, as is commonly thought, made in the conventional way that musical instruments are using specific tube shapes or apertures. Common whistle fuels contain benzoate or salicylate compounds and a suitable oxidizer such as potassium perchlorate.

Palm

A collection of palm-shell fireworks illuminating the beach of Tybee Island, Georgia, United States

A shell containing a relatively few large comet stars arranged in such a way as to burst with large arms or tendrils, producing a palm tree-like effect. Proper palm shells feature a thick rising tail that displays as the shell ascends, thereby simulating the tree trunk to further enhance the "palm tree" effect. One might also see a burst of color inside the palm burst (given by a small insert shell) to simulate coconuts.

Peony

A spherical break of colored stars that burn without a tail effect. The peony is the most commonly seen shell type.

Ring

A shell with stars specially arranged so as to create a ring. Variations include smiley faces, hearts, and clovers.

Roman candle

A Roman candle is a long tube containing several large stars which fire at a regular interval. These are commonly arranged in fan shapes or crisscrossing shapes, at a closer proximity to the audience. Some larger Roman candles contain small shells (bombettes) rather than stars.

Salute

A shell intended to produce a loud report rather than a visual effect. Salute shells usually contain flash powder, producing a quick flash followed by a very loud report resembling military artillery. Titanium may be added to the flash powder mix to produce a cloud of bright sparks around the flash. Salutes are commonly used in large quantities during finales to create intense noise and brightness. They are often cylindrical in shape to allow for a larger payload of flash powder, but ball shapes are common and cheaper as well. Salutes are also called Maroons.

Spider

A typical spider effect

A shell containing a fast burning tailed or charcoal star that is burst very hard so that the stars travel in a straight and flat trajectory before slightly falling and burning out. This appears in the sky as a series of radial lines much like the legs of a spider.

Time Rain

An effect created by large, slow-burning stars within a shell that leave a trail of large glittering sparks behind and make a sizzling noise. The "time" refers to the fact that these stars burn away gradually, as opposed to the standard brocade "rain" effect where a large amount of glitter material is released at once.

Willow

A willow is similar to a chrysanthemum, but with long-burning silver or gold stars that produce a soft, dome-shaped weeping willow-like effect.

Farfalle

Farfalle is an effect in Italian fireworks with spinning silver sprays in the air.

Tourbillion

A tourbillion is similar to a farfalle but has spinning stars.

Pulmonary edema

From Wikipedia, the free encyclopedia
Pulmonary edema
Other namesPulmonary oedema
Pulmonary edema with small pleural effusions on both sides
SpecialtyCardiology, critical care medicine

Pulmonary edema, also known as pulmonary congestion, is excessive liquid accumulation in the tissue and air spaces (usually alveoli) of the lungs. It leads to impaired gas exchange and may cause hypoxemia and respiratory failure. It is due to either failure of the left ventricle of the heart to remove oxygenated blood adequately from the pulmonary circulation (cardiogenic pulmonary edema), or an injury to the lung tissue directly or blood vessels of the lung (non-cardiogenic pulmonary edema).

Treatment is focused on three aspects: firstly improving respiratory function, secondly, treating the underlying cause, and thirdly preventing further damage and assuring full recovery to the lung. Pulmonary edema, especially when sudden (acute), can lead to respiratory failure or cardiac arrest due to hypoxia. It is a cardinal feature of congestive heart failure. The term edema is from the Greek οἴδημα (oidēma, "swelling"), from οἰδέω (oidéō, "(I) swell").

Types

Classically it is cardiogenic (left ventricular) but fluid may also accumulate due to damage to the lung. This damage may be from direct external injuries or injuries mediated by high pressures within the pulmonary circulation. When directly or indirectly caused by increased left ventricular pressure, pulmonary edema may form when mean pulmonary pressure rises from the normal average of 15 mmHg to above 25 mmHg, where pulmonary fluid may form. Broadly, the causes of pulmonary edema can be divided into cardiogenic and non-cardiogenic. By convention, cardiogenic specifically refers to left ventricular causes.

Cardiogenic

  • Congestive heart failure which is due to the heart's inability to pump the blood out of the pulmonary circulation at a sufficient rate resulting in elevation in pulmonary wedge pressure and edema – this usually is due to left ventricular failure, but may also be from arrhythmias, or fluid overload, (e.g. from kidney failure or intravenous therapy).
  • Hypertensive crisis can cause pulmonary edema as the elevation in blood pressure and increased afterload on the left ventricle hinders forward flow in blood vessels and causes the elevation in wedge pressure and subsequent pulmonary edema.

Non-cardiogenic

  • Negative pressure pulmonary edema in which a significant negative (internal) pressure in the chest (such as from an inhalation against an upper airway obstruction) ruptures capillaries and floods the alveoli with blood. Negative pressure pulmonary edema has an incidence in the range of 0.05-0.1% in cases of general anesthesia. The negative pressure causes a significant increase in preload, thereby increasing pulmonary blood volume.  There is also a significant increase in left ventricular afterload, which causes a decreased cardiac output.  The increase in pulmonary blood volume and pressure along with a decrease in cardiac output to the lungs will increase the pulmonary transudative pressures and the risk of pulmonary edema. With all this occurring, pulmonary vascular resistance increases causing a shift of the intraventricular septum.  The ventricular septal shift to the left causes a left ventricular diastolic dysfunction, which further increases pulmonary hydrostatic pressures and the risk.
  • Neurogenic causes (seizures, head trauma, strangulation, electrocution).
  • Pulmonary embolism

Acute lung injury may also cause pulmonary edema directly through injury to the vasculature and parenchyma of the lung. It includes acute lung injury and acute respiratory distress syndrome. (ALI-ARDS) cover many of these causes, but they may also include:

Some causes of pulmonary edema are less well characterised and arguably represent specific instances of the broader classifications above.

Signs and symptoms

The most common symptom of pulmonary edema is difficulty breathing (dyspnea), but may include other symptoms such as coughing up blood (classically seen as pink or red, frothy sputum), excessive sweating, anxiety, and pale skin. Shortness of breath can manifest as orthopnea (inability to breathe sufficiently when lying down flat due to breathlessness) and/or paroxysmal nocturnal dyspnea (episodes of severe sudden breathlessness at night). These are common presenting symptoms of chronic and cardiogenic pulmonary edema due to left ventricular failure. The development of pulmonary edema may be associated with symptoms and signs of "fluid overload" in the lungs; this is a non-specific term to describe the manifestations of right ventricular failure on the rest of the body and includes peripheral edema (swelling of the legs, in general, of the "pitting" variety, wherein the skin is slow to return to normal when pressed upon due to fluid), raised jugular venous pressure and hepatomegaly, where the liver is excessively enlarged and may be tender or even pulsatile. Other signs include end-inspiratory crackles (crackling sounds heard at the end of a deep breath) on auscultation and the presence of a third heart sound.

Flash pulmonary edema

Flash pulmonary edema (FPE) is rapid onset acute pulmonary edema. It is often associated with severe hypertension but may be precipitated by acute myocardial infarction or mitral regurgitation, but can be also caused by aortic regurgitation, heart failure, or almost any cause leading to elevated left ventricular filling pressures. Treatment of FPE should be directed at the underlying cause, but the mainstays are nitroglycerin, ensuring adequate oxygenation with non-invasive ventilation, and decrease of pulmonary circulation pressures while FPE stays.

Recurrence of FPE is thought to be associated with hypertension and may signify renal artery stenosis. Prevention of recurrence is based on managing or preventing hypertension, coronary artery disease, renovascular hypertension, and heart failure.

Diagnosis

X-Ray showing pulmonary edema
Pulmonary edema on CT-scan (coronal MPR)

There is no single test for confirming that breathlessness is caused by pulmonary edema – there are many causes of shortness of breath; but there are methods to suggest a high probability of an edema.

Low oxygen saturation in blood and disturbed arterial blood gas readings support the proposed diagnosis by suggesting a pulmonary shunt. A chest X-ray will show fluid in the alveolar walls, Kerley B lines, increased vascular shadowing in a classical batwing peri-hilum pattern, upper lobe diversion (biased blood flow to the superior parts instead of inferior parts of the lung), and possibly pleural effusions. In contrast, patchy alveolar infiltrates are more typically associated with noncardiogenic edema

Lung ultrasounds, employed by a healthcare provider at the point of care, is also a useful tool to diagnose pulmonary edema; not only is it accurate, but it may quantify the degree of lung water, track changes over time, and differentiate between cardiogenic and non-cardiogenic edema.

Especially in the case of cardiogenic pulmonary edema, urgent echocardiography may strengthen the diagnosis by demonstrating impaired left ventricular function, high central venous pressures and high pulmonary artery pressures leading to pulmonary edema.

Blood tests are performed for electrolytes (sodium, potassium) and markers of renal function (creatinine, urea). Liver enzymes, inflammatory markers (usually C-reactive protein) and a complete blood count as well as coagulation studies (PT, aPTT) are also typically requested as further diagnosis. B-type natriuretic peptide (BNP) is available in many hospitals, sometimes even as a point-of-care test. Low levels of BNP (<100 pg/ml) suggest a cardiac cause is unlikely.

Prevention

In those with underlying heart or lung disease, effective control of congestive and respiratory symptoms helps prevents pulmonary edema.

Dexamethasone is in widespread use for the prevention of high altitude pulmonary edema. Sildenafil is used as a preventive treatment for altitude-induced pulmonary edema and pulmonary hypertension, the mechanism of action is via phosphodiesterase inhibition which raises cGMP, resulting in pulmonary arterial vasodilation and inhibition of smooth muscle cell proliferation and indirectly fluid formation in the lungs. While this effect has only recently been discovered, sildenafil is already becoming an accepted treatment for this condition, in particular in situations where the standard treatment of rapid descent (acclimatization) has been delayed for some reason.

Management

The initial management of pulmonary edema, irrespective of the type or cause, is supporting vital functions while edema lasts. Therefore, if the level of consciousness is decreased it may be required to proceed to tracheal intubation and mechanical ventilation to prevent airway compromise. Hypoxia (abnormally low oxygen levels) may require supplementary oxygen to balance blood oxygen levels, but if this is insufficient then again mechanical ventilation may be required to prevent complications caused by hypoxia. Treatment of the underlying cause is the next priority; pulmonary edema secondary to infection, for instance, would require the administration of appropriate antibiotics or antivirals.

Cardiogenic pulmonary edema

Acute cardiogenic pulmonary edema often responds rapidly to medical treatment. Positioning upright may relieve symptoms. A loop diuretic such as furosemide (or Lasix®) is administered, often together with morphine to reduce respiratory distress. Both diuretic and morphine may have vasodilator effects, but specific vasodilators may be used (particularly intravenous glyceryl trinitrate or ISDN) provided the blood pressure is adequate.

Continuous positive airway pressure and bilevel positive airway pressure (CPAP/BiPAP) has been demonstrated to reduce mortality and the need of mechanical ventilation in people with severe cardiogenic pulmonary edema.

It is possible for cardiogenic pulmonary edema to occur together with cardiogenic shock, in which the cardiac output is insufficient to sustain an adequate blood pressure to the lungs. This can be treated with inotropic agents or by intra-aortic balloon pump, but this is regarded as temporary treatment while the underlying cause is addressed and the lungs recover.

Inequality (mathematics)

From Wikipedia, the free encyclopedia https://en.wikipedia.org/wiki/Inequality...