Football (ball)

A football is an inflated ball used to play one of the various sports known as football. The first balls were made of natural materials, such as an inflated pig bladder, sometimes inside a leather cover, which has given rise to the United States slang-term "pigskin." Modern balls are designed by teams of engineers to exacting specifications, with rubber or plastic bladders, and often with plastic covers. Various leagues and games use different balls, though they all have one of the following basic shapes:
 * 1) a sphere: used in Association football and Gaelic football
 * 2) a prolate spheroid
 * 3) * either with rounded ends: used in the rugby codes and Australian football
 * 4) * or with more pointed ends: used in American football and Canadian football

The precise shape and construction of footballs is typically specified as part of the rules and regulations.

The oldest football still in existence, which is thought to have been made circa 1540, was discovered in the roof of Stirling Castle, Scotland, in 1981. The ball is made of leather (possibly from a deer) and a pig's bladder. It has a diameter of between 14 –, weighs 125 g and is currently on display at the Smith Art Gallery and Museum in Stirling.

American and Canadian football


In North America, the term football usually refers to a ball made of leather, which is required in professional and collegiate football. Footballs used in recreation, and in organised youth leagues, may be made of rubber or plastic materials (the high school football rulebooks still allow the inexpensive all-rubber footballs, though they are less common than leather).

Leather panels are usually tanned to a natural brown color, which is usually required in professional leagues and collegiate play. At least one manufacturer uses leather that has been tanned to provide a "tacky" grip in dry or wet conditions. Historically, white footballs have been used in games played at night so that the ball can be seen more easily; however, this practice is no longer commonplace, as artificial lighting conditions have improved to the point where it is no longer necessary. Two indoor American football leagues, the Ultimate Indoor Football League and American Indoor Football, use a ball with red, white and blue panels. At most levels of play (but not, notably, the NFL), white stripes are painted on each end of the ball, halfway around the circumference, to improve nighttime visibility. The UFL uses a ball with lime-green stripes. In the CFL the stripes traverse the entire circumference of the ball. The XFL used a novel color pattern, a black ball with red curved lines in lieu of stripes, for its footballs; this design was redone in a tan and navy color scheme for the Arena Football League in 2003. The leather is usually stamped with a pebble-grain texture to help players grip the ball. Some or all of the panels may be stamped with the manufacturer's name, league or conference logos, signatures, and other markings.

Four panels or pieces of leather or plastic are required for each football. After a series of quality control inspections for weight and blemishes, workers begin the actual manufacturing process. Two of the panels are perforated along adjoining edges, so that they can be laced together. One of these lacing panels receives an additional perforation and reinforcements in its center, to hold the inflation valve.

Each panel is attached to an interior lining. The four panels are then stitched together in an "inside-out" manner. The edges with the lacing holes, however, are not stitched together. The ball is then turned right side out by pushing the panels through the lacing hole.

A polyurethane or rubber lining called a bladder is then inserted through the lacing hole.

Polyvinyl chloride or leather laces are inserted through the perforations, to provide a grip for holding, hiking and passing the football.

Before play, the ball is inflated to an air pressure of 12.5 to 13.5 psi. The ball weighs 14 to 15 oz.

In an NFL game, the home club must have 36 balls for an outdoor game or 24 for an indoor game, and they must be available for the referee to test with a pressure gauge two hours before the game. Twelve new footballs, sealed in a special box and shipped by the manufacturer, are opened in the officials’ locker room two hours before the game. These balls are specially marked with the letter "K" and used exclusively for the kicking game.

Dimensions
Law 2 of the game specifies that the ball is an air-filled sphere with a circumference of 68 - 70 cm, a weight of 410 - 450 g, inflated to a pressure of 0.6 to 1.1 atmospheres (59 - 108 kPa) "at sea level", and covered in leather or "other suitable material". The weight specified for a ball is the dry weight, as older balls often became significantly heavier in the course of a match played in wet weather. The standard ball is a Size 5, although smaller sizes exist: Size 3 is standard for team handball and Size 4 in futsal and other small-field variants. Other sizes are used in underage games or as novelty items.


 * Size 1
 * These mini-balls are only used for promotional purposes. They are normally made of synthetic material, built up in 32 panels, and they do not exceed 17 in in circumference.


 * Size 2
 * This size ball is sometimes used in promotional tournaments and during trainings for children. It is the same size ball used for playing by children under 4. The size 2 association football ball is made of synthetic material, plastic or PVC and it is not bigger than 22 in or heavier than 10 oz. It is the perfect size ball for practising drills and for improving one's handling skills.


 * Size 3
 * The size 3 association football balls are used by players under 8 because the balls are light (they do not weigh more than 12 oz and fairly small (24 in in circumference). They are usually made of 32 stitched or glued panels of synthetic materials or PVC. This is also the official size of balls used in handball.


 * Size 4
 * The size 4 balls are the standard balls for futsal but they may also be used in practices by players between 8 and 12 years old. They are spherical, weighing no more than 13 oz and with a maximum circumference of 26 in. They are normally made of leather or other suitable materials.


 * Size 5
 * This is the standard ball size with a circumference 69 cm ± 0.5 cm for the FIFA Approved standard (± 1.0 cm for the lesser FIFA Inspected standard) used in official FIFA championships all over the world. It is also the most widely used size of ball by players 12 years old or older. A size 5 association football ball could also be made from polyurethane. It is a less soft material that still retains a good feel and is much more durable. This material is a type of plastic, so it can increase the life of the ball dramatically.

History
Spherical footballs were invented shortly before the rules of association football were formalised. In 1855, Charles Goodyear designed and manufactured spherical footballs; these were made entirely of vulcanised rubber. In 1863, the English Football Association was formed and the rules of association football were established. However, there was no description on the ball size until 1873 when it was decided that the ball "must be spherical with a circumference of 27 - 28 in."

This rule still applies for the association football official matches played today all over the world. The early rules specified a weight of 13 - 15 oz which was however changed in 1937 to the current accepted weight, 14 - 16 oz. At the same time, the association agreed that the official association football ball must be covered in leather or any approved material.

A direct consequence of establishing the laws of the game by the English Football Association was the mass production of association football balls. The first two companies that started producing association football balls in larger quantities were Mitre and Thomlinson from Glasgow. They produced balls made of leather because they wanted to produce good quality association football balls that will retain their form after use. On the other hand, they preferred stitching the panels since that means better quality and better and longer resistance in what the ball concerns. The best covers which resulted in very expensive association football balls were the ones made from the rump of a cow. By the 20th century, the official balls were produced with rubber bladders which were able to withstand heavier pressure.

Until the 1950s the official balls used during association football matches had dark colors because of the color of the leather. In 1951 a white ball was first permitted to help spectators see the ball easier with the advent of floodlights. Even if they were used earlier in unofficial games, the official association football balls were permitted only in the mid-20th century.

Construction


Most modern footballs are stitched from 32 panels of waterproofed leather or plastic: 12 regular pentagons and 20 regular hexagons. The 32-panel configuration is the spherical polyhedron corresponding to the truncated icosahedron; it is spherical because the faces bulge from the pressure of the air inside. The first 32-panel ball was marketed by Select in the 1950s in Denmark. This configuration became common throughout Continental Europe in the 1960s, and was publicised worldwide by the Adidas Telstar, the official ball of the 1970 World Cup.

The familiar 32-panel football design is sometimes referenced to describe the truncated icosahedron Archimedean solid, carbon buckyballs or the root structure of geodesic domes.



Balls are usually stitched from non-waterproof plastic, similar to the design of the modern volleyballs and Gaelic footballs, and laced to allow access to the internal air bladder.

The official FIFA World Cup football for Germany 2006 matches was the 14-panel Adidas +Teamgeist. It was made in Pakistan and Thailand by Adidas, who have provided the official match balls for the tournament since 1970, and is a "thermally bonded" machine-pressed ball, rather than a traditionally stitched one. Adidas will continue to supply the official football for the 2010 and 2014 World Cups. In 2010, the official match ball Jabulani's design received criticism, with former Arsenal goalkeeper Bob Wilson describing it as a "beach ball" responsible for a rise in errors by goalkeepers and Spanish goalkeeper Iker Casillas also called it too rough for the goalkeepers.

Another ball with an innovative pattern is the 26-panel Mitre PRO 100T.

There are also indoor footballs, which are made of one or two pieces of plastic. Often these have designs printed on them to resemble a stitched leather ball.

Chip-enabled ball
The Chip-enabled football was invented by Adidas, the Fraunhofer Institute for Integrated circuits in Erlangen and the company Cairos Technologies. The ball contains an integrated ASIC-Chip and a transmitter for the transfer of data. The chip is suspended in the middle of the football and sends a signal to a receiver at the referee's wrist once the ball passed the outer goal-line.

The first tests were performed in Nuremberg. The stadium is equipped with twelve antennas in light masts and other locations distributed around the arena which collect data that is transmitted from the chip. The antennas are connected to a fiber optic cable which routes the data to servers in order to analyze them. The system was first used during the FIFA U-17 World Cup in Peru.

Child labor worries
Pakistan is the largest manufacturer of footballs on the planet. About 80% of association footballs are made in Pakistan. 75% of these (60% of all world production) are made in the city of Sialkot. Child labor was commonly used in the production of the balls before the 21st century. In 1996, during the European championship, activists lobbied to end the use of child labor. This eventually led to the Atlanta Agreement, which seeks to reform the industry to eliminate the use of child labor in the production of balls. This also led to a centralisation of production, which on the one hand would make it easier for the Independent Monitoring Association for Child Labour (IMAC) —an organisation created to watch over the Atlanta Agreement—to make sure no child labor occurred, on the other hand often forced workers to commute further to get to work. The problem was largely due to highly skilled but uneducated class of labour force who would prefer to have their children learn the craft as opposed to going to school.

Australian rules football
The football used in Australian football is similar to a rugby ball but generally slightly smaller and more rounded at the ends, but more elongated in overall appearance, being longer by comparison with its width than a rugby ball. A regulation football is 720 - 730 mm in circumference, and 545 - 555 mm transverse circumference, and inflated to a pressure of 62 - 76 kPa. In the AFL, the balls are red for day matches and yellow for night matches.

Australian football ball brands include Burley, Ross Faulkner, and Sherrin (the brand used mainly by the Australian Football League).

The Australian football ball was invented by T.W. Sherrin in 1880, after he was given a misshapen rugby ball to fix. Sherrin designed the ball with indented rather than pointy ends to give the ball a better bounce. Before this time,a round ball was used from the 1850s to 1870s and later rugby balls were used to play the game.

Gaelic football


Gaelic football is played with a spherical leather ball, roughly 25 cm in diameter and 69 - 74 cm in circumference. A dry ball weighs between 370 and 425 g. The pattern of panels is identical to the volleyball, consisting of six groups perpendicular to each other, each group being composed of two trapezoidal panels and one rectangular panel; 18 panels in all.

Gaelic footballs are also the standard balls used in international rules football.

Although Gaelic football has been played with a round ball since first organised in 1887, balls made by the Irish sports company O'Neills have been used sometime since the company was founded in 1918 and are recognised as the official ball to be played with, although it is now permitted to use the Gaelic ball manufactured by the Irish sports company Gaelic Gear.

Rugby football
Richard Lindon and Bernardo Solano started making balls for Rugby school out of hand stitched, four-panel, leather casings and pigs’ bladders. The rugby ball's distinctive shape is supposedly due to the pig’s bladder, although early balls were more plumb-shape than oval. The balls varied in size in the beginning depending upon how large the pig’s bladder was.

Until 1870, rugby was played with a near spherical ball with an inner-tube made of a pig's bladder. In 1870 Richard Lindon introduced rubber inner-tubes and because of the pliability of rubber the shape gradually changed from a sphere to an egg. In 1892 the RFU endorsed ovalness as the compulsory shape. The gradual flattening of the ball continued over the years. The introduction of synthetic footballs over the traditional leather balls, in both rugby codes, was originally governed by weather conditions. If the playing surface was wet, the synthetic ball was used, as it didn't absorb water and become heavy. Eventually, the leather balls were phased out completely.

Rugby league
Rugby league is played with a prolate spheroid shaped football which is inflated with air. A referee will stop play immediately if the ball does not meet the requirements of size and shape. Traditionally made of brown leather, modern footballs are synthetic and manufactured in a variety of colours and patterns. Senior competitions should use light coloured balls to allow spectators to see the ball more easily. The football used in rugby league is known as "international size" or "size 5" and is approximately 27 cm long and 60 cm in circumference at its widest point. Smaller-sized balls are used for junior versions of the game, such as "Mini" and "Mod". A full size ball weighs between 383 and 440 g. Rugby league footballs are slightly more pointed than rugby union footballs and larger than American footballs.

The Australasian National Rugby League and European Super League use balls made by Steeden. Steeden is also sometimes used as a noun to describe the ball itself.

Rugby union
The ball used in rugby union, usually referred to as a rugby ball, is a prolate spheroid essentially elliptical in profile. Traditionally made of brown leather, modern footballs are manufactured in a variety of colors and patterns. A regulation football is 28 - 30 cm long and 58 - 62 cm in circumference at its widest point. It weighs 410 - 460 g and is inflated to 65.7 - 68.8 kPa.

In 1980, leather-encased balls, which were prone to water-logging, were replaced with balls encased in synthetic waterproof materials. The Gilbert Synergie was the match ball of the 2007 Rugby World Cup.