Fireworks

Fireworks are a class of low explosive pyrotechnic devices used for aesthetic and entertainment purposes. The most common use of a firework is as part of a fireworks display (also called a fireworks show or pyrotechnics), a display of the effects produced by firework devices.

Fireworks

Fireworks over Sydney Harbour on New Year's Eve 2006–07.

Fireworks closer view at Lunar New Year celebration in New York, 2003

A fireworks display on Taipei 101, Taiwan, which in 2005 held the world's first fireworks display on a supertall skyscraper.

2013 Bastille Day fireworks over Paris, France.

Fireworks on Qatar National Day 2018 in Doha

Fireworks 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 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).

New Year fireworks

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. 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. Such rocket technology has also been used for the delivery of mail by rocket and is used as propulsion for most model rockets.

Fireworks were originally invented in China. Cultural events and festivities such as the 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.

Modern colored fireworks were invented in Europe in the 1830s.[1] Modern skyrocket fireworks have been made since the early 20th century.

History

An illustration of a fireworks display from the 1628-1643 edition of the Ming Dynasty novel Jin Ping Mei.[2]

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.[3]

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).[4] Fireworks were used to accompany many festivities.[5] The art and science of firework making has developed into an independent profession. In China, pyrotechnicians were respected for their knowledge of complex techniques in mounting firework displays.[6]

During the Han dynasty (202 BC – 220 AD), people threw bamboo stems into a fire to produce an explosion with a loud sound.[7] In later times, gunpowder packed into small containers was used to mimic the sounds of burning bamboo.[7] Exploding bamboo stems and gunpowder firecrackers were interchangeable known as baozhu (爆竹) or baogan (爆竿).[7] 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.[8] 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.[8] By the 12th and possibly the 11th century, the term baozhang (爆仗) was used to specifically refer to gunpowder firecrackers.[7]

During the Song dynasty, many of the common people could purchase various kinds of fireworks from market vendors.[9] 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.[10] 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).[11] Rocket propulsion was common in warfare, as evidenced by the Huolongjing compiled by Liu Bowen (1311–1375) and Jiao Yu (fl. c. 1350–1412).[12] 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".[5][13]

In regards to colored fireworks, this was derived and developed from earlier (possibly Han dynasty or soon thereafter) Chinese application of chemical substances to create colored smoke and fire.[14] 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.[14] 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.[14] 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.[14] These included, for instance, arsenical sulphide for yellow, copper acetate (verdigris) for green, lead carbonate for lilac-white, and mercurous chloride (calomel) for white.[14] 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." or the English geographer Sir John Barrow (ca. 1797) who 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."[14]

Fireworks were produced in Europe by the 14th century, becoming popular by the 17th century.[15][1][16] Lev Izmailov, ambassador of Peter the Great, once reported from China: "They make such fireworks that no one in Europe has ever seen."[16] In 1758, the Jesuit missionary Pierre Nicolas le Chéron d'Incarville, living in Beijing, wrote about the methods and composition on how to make many types of Chinese fireworks to the Paris Academy of Sciences, which revealed and published the account five years later.[17] Amédée-François Frézier published his revised work Traité des feux d'artice pour le spectacle (Treatise on Fireworks) in 1747 (originally 1706),[18] 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."[15] 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.[15] Modern colored fireworks were invented in Europe in the 1830s.[1] Modern skyrocket fireworks have been made since the early 20th century.

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 are also a problem for animals, both domestic and wild, which 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.[19][20][21]

Competitions

Pyrotechnical competitions involving fireworks 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. The event is one of the largest and most intense international fireworks competitions.

Clubs

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.,[22] organized in 1976 in the Eastern Seaboard region of the U.S.

PGI annual convention

The Pyrotechnics Guild International, Inc. or PGI,[23] founded in 1969, is an independent worldwide nonprofit organization of amateur and professional fireworks enthusiasts. It is notable for its large number of members, around 3,500 in total. The PGI exists solely to further the safe usage and enjoyment of both professional grade and consumer grade fireworks while both advancing the art and craft of pyrotechnics and preserving its historical aspects. Each August the PGI conducts its annual week-long convention, where some the world's biggest and best fireworks displays occur. Vendors, competitors, and club members come from around the US and from various parts of the globe to enjoy the show and to help out at this all-volunteer event. Aside from the nightly firework shows, the competition is a highlight of the convention. This is a completely 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.

Amateur and professional members can come to the convention to purchase fireworks, paper goods, novelty items, non-explosive chemical components and much more at the PGI trade show. Before the nightly fireworks displays and competitions, club members have a chance to enjoy open shooting of any and all legal consumer or professional grade fireworks, as well as testing and display of hand-built fireworks. The week ends with the Grand Public Display on Friday night, which gives the chosen display company a chance to strut their stuff in front of some of the world's biggest fireworks aficionados. The stakes are high and much planning is put into the show. In 1994 a shell of 36 inches (914 mm) in diameter was fired during the convention, more than twice as large as the largest shell usually seen in the US, and shells as large as 24 inches (610 mm) are frequently fired.

Halloween

Canada

Both fireworks and firecrackers are a popular tradition during Halloween in Vancouver, although apparently this is not the custom elsewhere in Canada.

Ireland

In the Republic of Ireland and Northern Ireland there are many fireworks displays, during the Halloween season. The largest are in the cities of Belfast, Derry, and Dublin. The 2010 Derry Halloween fireworks attracted an audience of over 20,000 people.[24] The sale of fireworks is strongly restricted in the Republic of Ireland, though many illegal fireworks are sold throughout October or smuggled from Northern Ireland. In the Republic 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.[25]

United States

Two firework displays on All Hallows' Eve in the United States are the annual "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 used in the public celebration of major events such as New Year's Eve.

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 [26]

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, in total numbering more than 200 during August. 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 (men only), collecting 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.[27]

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

Malta

Fireworks at a Maltese festival in 2014

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.[28]

Nowadays, fireworks are used in village feasts throughout the summer. The Malta International Fireworks Festival is also held annually.[29]

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.[30] The event is held in Port Hercule, beginning at around 9:30pm every night, depending on the sunset.[31]

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 over 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.[32]

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:[33]

After Dark fireworks, Sheffield homepage
Bangers on the Beach (Holyhead Round Table charity fireworks), Holyhead homepage
Battel Bonfire in Battle, East Sussex homepage
Blackheath Fireworks, London homepage
Bught Park fireworks, Inverness homepage
Fireworks with Vikings, Tutbury, Staffordshire homepage
Flaming Tar Barrels, Ottery St Mary homepage
Glasgow Green fireworks homepage
Halloween Happening fireworks, Derry homepage
Midsummer Common, Cambridge homepage
Sparks in the Park (Cardiff Round Table charity fireworks), Cardiff homepage

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. 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.[34] The Walt Disney Company is now the largest consumer of fireworks in the world.[35]

Uses other than public displays

In addition to large public displays, people often buy small amounts 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 bird scarers.

Pyrotechnic compounds

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

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
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.[36] 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.[37] 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 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, beryllium, 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.[15]

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 impart 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 ¹⁄₄–4 inches (6.4–101.6 mm), and a single cake can have over 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 4 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

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, small shells, as well as just stars. Although mines up to 12 inches (305 mm) diameter appear on occasion, they are usually between 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 a gunshot; technically a "report".
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

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. 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

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

Hazards and regulation

A firework rocket preparing its launch on the American Independence Day.

Safety

Fireworks pose risks of injury to people, and of damage, largely as a fire hazard.

Pollution

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. 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.[38]

Several US 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.[39] 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.[40]

Pollutants from fireworks raise concerns because of potential health risks associated with hazardous by-products. For most people the effects of exposure to low levels of toxins from many sources over long periods are unknown. For persons with asthma or multiple chemical sensitivity the smoke from fireworks may aggravate existing health problems.[41] Environmental pollution is also a concern because heavy metals and other chemicals from fireworks may contaminate water supplies and because fireworks combustion gases might contribute to such things as acid rain which can cause vegetation and even property damage. However, gunpowder smoke and the solid residues are basic, and as such the net effect of fireworks on acid rain is debatable. The carbon used in fireworks is produced from wood and does not lead to more carbon dioxide in the air. 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. Few governmental entities, by contrast, effectively limit pollution from burning fossil fuels such as diesel fuel or coal. Coal-fueled electricity generation alone is a much greater source of heavy metal contamination in the environment than fireworks.

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.[42]