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Artificial Turf General Information

Home Improvement Return on Investment

How does a 100% to 200% return on investment sound to you?  Too good to be true?  Not according to a Money Magazine story on home renovations or Penn State University, Dept. of Landscape Architecture.  They both agree that a well done landscaping home improvement offers the best return on investment of any home improvement you can make; and that you will get a 100% to 200% return on your investment when applied to a home’s resale value.  This far surpasses the R.O.I. you could hope to gain from a kitchen remodel, bath remodel, swimming pool, or any home improvement.  Yet homeowners rarely think of landscaping, when remodeling in hopes of commanding a higher asking price.  Even if you aren’t planning to move, it’s nice to know you are adding real value to your home by installing synthetic grass.  Not to mention the savings from the water and maintenance costs of maintaining real grass, and it looks better!  Fake grass harmonizes well with surrounding foliage.  Our new products are very realistic and compliment nature which gives your home great curb appeal. 
            A real estate appraiser or agent would tell you that landscaping contributes to a home in two ways.  First it simply adds to the total value of the property, and second is the role landscaping plays when trying to sell a house.  It’s tough to measure how powerful a value-oriented landscape could be in the selling process.  For a prospective buyer it is very hard to separate the house and the landscaping.  Two houses being equal in all other respects, the one with better curbside appeal will sell faster.  Though it’s difficult to define what makes a landscape pleasing it’s obvious to everyone when something’s not.  A crumby lawn speaks to the type of owner and how the entire house is cared for.   A beautiful lawn can increase the perceived square footage of a home because this is seen as really useable area.

Artificial Turf Background, Applications, Advantages, and Disadvantages

Artificial turf, or synthetic turf, is a man-made surface manufactured from synthetic materials, made to look like natural grass. It is most often used in arenas for sports that were originally or are normally played on grass. However, it is now being used on residential lawns and commercial applications as well.

Background

David Chaney -- who moved to Raleigh in 1960 and later served as dean of the North Carolina State University College of Textiles -- headed the team of RTP researchers who created the famous artificial turf. That accomplishment led Sports Illustrated to declare Chaney as the man "responsible for indoor major league baseball and millions of welcome mats." Artificial turf first came to prominence in 1965, when AstroTurf was installed in the newly-built Astrodome in Houston, Texas. The use of AstroTurf and similar surfaces became widespread in the 1970s and was installed in both indoor and outdoor stadiums used for baseball and gridiron football in the United States and Canada. Maintaining a grass playing surface indoors, while technically possible, is prohibitively expensive, while teams who chose to play on artificial surfaces outdoors did so because of the reduced maintenance cost, especially in colder climates with urban multi-purpose "cookie cutter" stadiums such as Cincinnati's Riverfront Stadium, Pittsburgh's Three Rivers Stadium and Philadelphia's Veterans Stadium.

Applications

Football (Soccer)

Soccer Field with Artificial Turf

Tropicana Field equipped with artificial turf

Some football (soccer) clubs in Europe installed artificial surfaces in the 1980s, which were called plastic pitches (often derisively) in countries such as England. In England several professional club venues had adopted the pitches, QPR's Loftus Road, Luton Town's Kenilworth Road, Oldham Athletic's Boundary Park and Preston's Deepdale until the English FA banned them in 1988. Artificial turf gained a bad reputation on both sides of the Atlantic with fans and especially with players. The first artificial turfs were a far harder surface than grass, and soon became known as an unforgiving playing surface which was prone to cause more injuries, and in particular, more serious joint injuries, than would comparatively be suffered on a grass surface. Artificial turf was also regarded as aesthetically unappealing to many fans.

In 1981, London football club Queens Park Rangers dug up its grass pitch and installed an artificial one. Others followed, and by the mid-1980s there were four plastic grass pitches in operation in the English league. They soon became a national joke: the ball pinged round like it was made of rubber, the players kept losing their footing, and anyone who fell over risked carpet burns. Unsurprisingly, fans complained that the football was awful to watch and, one by one, the clubs returned to natural grass.^[1]

In the 1990s many North American football clubs also removed their artificial surfaces and re-installed grass, while others moved to new stadiums with state-of-the-art grass surfaces that were designed to withstand cold temperatures where the climate demanded it. The use of artificial turf was later banned by FIFA, UEFA and by many domestic football associations, though, in recent years, both governing bodies have expressed an interest in resurrecting the use of artificial surfaces as the related technologies continue to evolve. UEFA has now been heavily involved in programs to test artificial turf with tests made in several grounds meeting with FIFA approval. A team of UEFA, FIFA and German company Polytan conducted tests in the Stadion Salzburg Wals-Siezenheim in Salzburg, Austria which is due to have matches played on it in the UEFA EURO 2008. It is the second FIFA 2 Star approved football turf pitch in a European domestic top flight, after Dutch club Heracles Almelo received the FIFA certificate in August last year.^[2] The tests were approved.^[3]

Soccer field developments

Modern artificial grass

In the early 21st century, new artificial playing surfaces using sand and/or rubber infill were developed. These "next generation" or "third generation" artificial grass surfaces are often virtually indistinguishable from natural grass when viewed from any distance, and are generally regarded as being about as safe to play on as a typical natural grass surface — perhaps even safer in cold conditions.

Crumb rubber

Crumb rubber is a term usually applied to recycled rubber from automotive and truck scrap tires. During the recycling process steel and fluff is removed leaving tire rubber with a granular consistency. Continued processing with a granulator and/or cracker mill, possibly with the aid of cryogenics, reduces the size of the particles further. The particles are sized and classified based on various criteria including color (black only or black and white). The granulate is sized by passing through a screen, the size based on a dimension (1/4") or mesh (holes per inch : 10, 20, etc.).

Mesh refers to material that has been sized by passing through a screen with a given number of holes per inch. For example, 10 mesh crumb rubber has passed through a screen with 10 holes per inch resulting in rubber granulate that is slightly less than 1/10th of an inch. The exact size will depend on the size of wire used in the screen.

Rubberized asphalt is the largest market for crumb rubber in the United States, consuming an estimated 220 million pounds, or approximately 12 million tires annually.^[1] Crumb rubber is also used as ground cover under playground equipment, and as a surface material for running tracks and athletic fields.^[1]

Description of crumb rubber grading:

The following are common classifications of crumb rubber:

Retreaders Tire Buffings shall consist of clean, fresh, dry buffings from tire retread preparation operations.

No.1 - Tire Granule shall consist of granulated tire crumb, Black Only Guaranteed MetalFree, sized. Magnetically separated materials are not acceptable. Fluff from tire cord removed.

No.2 - Tire Granule shall consist of granulated tire crumb, Black & White Guaranteed MetalFree, sized to minus 40 Mesh. Magnetically separated materials are not acceptable. Fluff from tire cord removed.

No.3 - Tire Granule shall consist of granulated tire crumb, Black Only Magnetically Separated, sized. Fluff from tire cord removed.

No.4 - Tire Granule shall consist of granulated tire crumb, Black & White Magnetically Separated, sized. Fluff from tire cord removed.

No.5 - Tire Granule shall consist of unclassified granulated tire crumb, Sized, Unseparated, not magnetically separated, fluff from tire cord not removed.

 

Many clubs have installed the new synthetic grass surfaces, most commonly as part of an all-weather training capability. Other clubs which have maintained natural grass surfaces are now re-considering artificial grass. With football clubs in Europe are looking to reduce both the maintenance costs and the number of winter matches that are cancelled due to frozen pitches, the issue has also been re-visited by that sport's governing bodies.

The Scottish Premier League banned synthetic pitches for competition matches in 2005, following a two year experiment by Dunfermline Athletic who installed XL Turf, made by the Swiss firm, XL Generation. The management of Dunfermline were happy with the surface, but the league banned the use of the artificial pitch due to complaints by visiting clubs such as Rangers and Celtic).

"The most common type uses polypropylene "grass" about 5 centimetres long, which is lubricated with silicone and tufted into a primary cloth and then latex is applied to the back of the cloth to give it stability by anchoring in the tufts. The whole thing is then "infilled" with a 4-centimetre layer of sand and rubber granules, which keeps the fibres upright and provides the right level of shock absorbency and deformability. The majority of the 15 or so turf manufacturers approved by FIFA use this technology. The other sort, typified by Dunfermline's pitch, has a base of expanded polyethylene, a foamy material originally developed as a shock absorber for the car industry (see diagram). The grass is also made of lubricated polyethylene fibres, but they are shorter and more densely packed than on an infilled pitch, and are also interspersed with short, curly, spring-like fibres that keep the blades upright. The finishing touch is an 8-millimetre filling of rubber granules." ^[1]The installation at the Borussia-Park in Mönchengladbach is another major step in the quality and development of artificial turf surfaces.^[4]

Polypropylene

Polypropylene lid of a Tic Tacs box, with a living hinge and the resin identification code under its flap

Micrograph of polypropylene

Polypropylene or polypropene (PP) is a thermoplastic polymer, made by the chemical industry and used in a wide variety of applications, including packaging, textiles (e.g., ropes, thermal underwear and carpets), stationery, plastic parts and reusable containers of various types, laboratory equipment, loudspeakers, automotive components, and polymer banknotes. An addition polymer made from the monomer propylene, it is rugged and unusually resistant to many chemical solvents, bases and acids. Polypropene is commonly recycled, and has the number "5" as its recycling symbol: .

Melt processing of polypropylene can be achieved via extrusion and molding. Common extrusion methods include production of melt blown and spun bond fibers to form long rolls for future conversion into a wide range of useful products such as face masks, filters, nappies and wipes.

The most common shaping technique is injection molding, which is used for parts such as cups, cutlery, vials, caps, containers, housewares and automotive parts such as batteries. The related techniques of blow molding and injection-stretch blow molding are also used, which involve both extrusion and molding.

The large number of end use applications for PP are often possible because of the ability to tailor grades with specific molecular properties and additives during its manufacture. For example, antistatic additives can be added to help PP surfaces resist dust and dirt. Many physical finishing techniques can also be used on PP, such as machining. Surface treatments can be applied to PP parts in order to promote adhesion of printing ink and paints.

Chemical and physical properties

Most commercial polypropylene is isotactic and has an intermediate level of crystallinity between that of low density polyethylene (LDPE) and high density polyethylene (HDPE); its Young's modulus is also intermediate. Through the incorporation of rubber particles, PP can be made both tough and flexible, even at low temperatures. This allows polypropylene to be used as a replacement for engineering plastics, such as ABS. Polypropylene is rugged, often somewhat stiffer than some other plastics, reasonably economical, and can be made translucent when uncolored but is not as readily made transparent as polystyrene, acrylic or certain other plastics. It can also be made opaque and/or have many kinds of colors through the use of pigments. Polypropylene has very good resistance to fatigue, so that most plastic living hinges, such as those on flip-top bottles, are made from this material. Very thin sheets of polypropylene are used as a dielectric within certain high performance pulse and low loss RF capacitors.

Polypropylene has a melting point of ~160°C (320°F), as determined by Differential Scanning Calorimetry (DSC). Many plastic items for medical or laboratory use can be made from polypropylene because it can withstand the heat in an autoclave. Food containers made from it will not melt in the dishwasher, and do not melt during industrial hot filling processes. For this reason, most plastic tubs for dairy products are polypropylene sealed with aluminium foil (both heat-resistant materials). After the product has cooled, the tubs are often given lids made of a less heat-resistant material, such as LDPE or polystyrene. Such containers provide a good hands-on example of the difference in modulus, since the rubbery (softer, more flexible) feeling of LDPE with respect to PP of the same thickness is readily apparent. Rugged, translucent, reusable plastic containers made in a wide variety of shapes and sizes for consumers from various companies such as Rubbermaid and Sterilite are commonly made of polypropylene, although the lids are often made of somewhat more flexible LDPE so they can snap on to the container to close it. Polypropylene can also be made into disposable bottles to contain liquid, powdered or similar consumer products, although HDPE and polyethylene terephthalate are commonly also used to make bottles. Plastic pails, car batteries, wastebaskets, cooler containers, dishes and pitchers are often made of polypropylene or HDPE, both of which commonly have rather similar appearance, feel, and properties at ambient temperature.

The MFR (Melt Flow Rate) or MFI (Melt Flow Index) is an indication of PP's molecular weight. This helps to determine how easily the melted raw material will flow during processing. Higher MFR PPs fill the plastic mold more easily during the injection or blow molding production process. As the melt flow increases, however, some physical properties, like impact strength, will decrease.

There are three general types of PP: homopolymer, random copolymer and impact or block copolymer. The comonomer used is typically ethylene. Ethylene-propylene rubber added to PP homopolymer increases its low temperature impact strength. Randomly polymerized ethylene monomer added to PP homopolymer decreases the polymer crystallinity and makes the polymer more transparent.

Degradation

Polypropylene is liable to chain degradation from exposure to UV radiation such as that present in sunlight. This is one main reason for not using it transparent instead of glass. For external applications, UV-absorbing additives must be used. Carbon black also provides some protection from UV attack. The polymer can also be oxidised at high temperatures, a common problem during moulding operations. Anti-oxidants are normally added to prevent polymer degradation.

Synthesis

Short segments of polypropylene, showing examples of isotactic (above) and syndiotactic (below) tacticity.

An important concept in understanding the link between the structure of polypropylene and its properties is tacticity. The relative orientation of each methyl group (CH₃ in the figure at left) relative to the methyl groups on neighboring monomers has a strong effect on the finished polymer's ability to form crystals, because each methyl group takes up space and constrains backbone bending.

Like most other vinyl polymers, useful polypropylene cannot be made by radical polymerization due to the higher reactivity of the allylic hydrogen (leading to dimerization) during polymerization. Moreover, the material that would result from such a process would have methyl groups arranged randomly, so called atactic PP. The lack of long-range order prevents any crystallinity in such a material, giving an amorphous material with very little strength and only specialized qualities suitable for niche end uses.

A Ziegler-Natta catalyst is able to limit incoming monomers to a specific orientation, only adding them to the polymer chain if they face the right direction. Most commercially available polypropylene is made with such Ziegler-Natta catalysts, which produce mostly isotactic polypropylene (the upper chain in the figure above). With the methyl group consistently on one side, such molecules tend to coil into a helical shape; these helices then line up next to one another to form the crystals that give commercial polypropylene many of its desirable properties.

A ball-and-stick model of syndiotactic polypropylene.

More precisely engineered Kaminsky catalysts have been made, which offer a much greater level of control. Based on metallocene molecules, these catalysts use organic groups to control the monomers being added, so that a proper choice of catalyst can produce isotactic, syndiotactic, or atactic polypropylene, or even a combination of these. Aside from this qualitative control, they allow better quantitative control, with a much greater ratio of the desired tacticity than previous Ziegler-Natta techniques. They also produce narrower molecular weight distributions than traditional Ziegler-Natta catalysts, which can further improve properties.

To produce a rubbery polypropylene, a catalyst can be made which yields isotactic polypropylene, but with the organic groups that influence tacticity held in place by a relatively weak bond. After the catalyst has produced a short length of polymer which is capable of crystallization, light of the proper frequency is used to break this weak bond, and remove the selectivity of the catalyst so that the remaining length of the chain is atactic. The result is a mostly amorphous material with small crystals embedded in it. Since each chain has one end in a crystal but most of its length in the soft, amorphous bulk, the crystalline regions serve the same purpose as vulcanization.

Mechanism of metallocene catalysts

The reaction of many metallocene catalysts requires a co catalyst for activation. One of the most common co catalysts for this purpose is Methylalmuinoxane (MAO)^[1]. Other co catalysts include, Al(C₂H₅)₃^[2].There are numerous metallocene catalysts that can be used for propylene polymerization. (Some metallocene catalysts are used for industrial process, while others are not, due to their high cost.) One of the simplest is Cp₂MCl₂ (M = Zr, Hf). Different catalyst can lead to polymers with different molecular weights and properties. Active research is still being conducted on metallocene catalyst.

In the mechanism the metallocene catalyst first reacts with the co catalyst. If MAO is the co catalyst, the first step is to replace one of the Cl atoms on the catalyst with a methyl group from the MAO. The methyl group on the MAO is replaced by the Cl from the catalyst. The MAO then removes another Cl from the catalyst. This makes the catalyst positively charged and susceptible to attack from propylene^[3].

Once the catalyst is activated, the double bond on the propene coordinates with the metal of the catalyst. The methyl group on the catalyst then migrates to the propene, and the double bond is broken. This starts the polymerization. Once the methyl migrates the positively charged catalyst is reformed and another propene can coordinate to the metal. The second propene coordinates and the carbon chain that was formed migrates to the propene. The process of coordination and migration continues and a polymer chain is grown off of the metallocene catalyst.^{[4] [5]}

History

Polypropylene was first polymerized by Dr. Karl Rehn at Hoechst AG in Germany in 1951, who didn't recognize the importance of his discovery. It was then rediscovered on March 11 1954 by Giulio Natta. At first it was thought that it would be cheaper than polyethylene.^[6]

Practical applications

A common application for polypropylene is as Biaxially Oriented polypropylene (BOPP). These BOPP sheets are used to make a wide variety of materials including clear bags. When polypropylene is biaxially oriented, it becomes crystal clear and serves as an excellent packaging material for artistic and retail products.

Polypropylene, highly colorfast, is widely used in manufacturing rugs and mats to be used at home. ^[7]

In New Zealand, in the US military, and elsewhere, polypropylene, or 'polypro' (New Zealand 'polyprops'), has been used for the fabrication of cold-weather base layers, such as long-sleeve shirts or long underwear. ( More recently, polyester replace polypropylene in these applications in the U.S. military. ^[8] ) Polypropylene is also used in warm-weather gear such as some Under Armour clothing, which can easily transport sweat away from the skin. These polypropylene clothes are not easily flammable, however, they can melt, which may result in severe burns if the service member is involved in an explosion or fire of any kind.^[9]

Polypropylene is widely used in ropes, distinctive because they are light enough to float in water. ^[10]

Polypropylene is also used as an alternative to polyvinyl chloride (PVC) as insulation for electrical cables for LSZH cable in low-ventilation environments, primarily tunnels. This is because it emits less smoke and no toxic halogens, which may lead to production of acid in high temperature conditions.

Polypropylene is also used in particular roofing membranes as the waterproofing top layer of single ply systems as opposed to modified bit systems.

Its most common medical use is in the synthetic, nonabsorbable suture Prolene, manufactured by Ethicon Inc.

Polypropylene is most commonly used for plastic moldings where it is injected into a mold while molten, forming complex shapes at relatively low cost and high volume, examples include bottle tops, bottles and fittings.

Recently it has been produced in sheet form and this has been widely used for the production of stationary folders, packaging and storage boxes. The wide colour range, durability and resistance to dirt make it ideal as a protective cover for papers and other materials. It is used in Rubik's cube stickers because of these characteristics.

The availability of sheet polypropylene has provided an opportunity for the use of the material by designers. The light weight, durable and colourful plastic makes an ideal medium for the creation of light shades and a number of designs have been developed using interlocking sections to create elaborate designs.

Polypropylene sheets are a popular choice for trading card collectors; these come with pockets (nine for standard size cards) for the cards to be inserted and are used to protect their condition and are meant to be stored in a binder.

Polypropylene has been used in hernia repair operations to protect the body from new hernias in the same location. A small patch of the material is placed over the spot of the hernia, below the skin, and is painless and is rarely, if ever, rejected by the body.

The material has recently been introduced into the fashion industry through the work of designers such as Anoush Waddington who have developed specialized techniques to create jewellery and wearable items from polypropylene.

Expanded Polypropylene (EPP) is a foam form of polypropylene. EPP has very good impact characteristics due to its low stiffness, this allows EPP to resume its shape after impacts. EPP is extensively used in model aircraft and other radio controlled vehicles by hobbyists. This is mainly due to its ability to absorb impacts, making this an ideal material for RC aircraft for beginners and amateurs.

 

UEFA later announced that starting from the 2005-06 season, approved artificial surfaces were to be permitted in their competitions.

Regardless of the views of the governing bodies, criticism of artificial surfaces in soccer continues, notably in reference to the FieldTurf surface at Toronto F.C.'s BMO Field and the Giants Stadium home of Red Bull New York. Current and former players have recently criticised the surface, expressing concerns that, among other things, it may exacerbate injuries.

A full international fixture for the 2008 European Championships was played on 17 October 2007 between England and Russia on an artificial surface, which was installed to counteract adverse weather conditions, at the Luzhniki Stadium in Moscow.^[5][6] It was one of the first full international games to be played on such a surface approved by both FIFA and UEFA. However UEFA ordered that the 2008 European Champions League final hosted in the same stadium in May 2008 must take place on grass, so a temporary natural grass pitch was installed just for the final. UEFA stressed that artificial turf should only be considered an option where climatic conditions necessitate.^[7]

Ski & Snowboard

Some ski and snowboard clubs and resorts in Europe installed artificial surfaces in the 1960s and 1970s. Often called pista del sole, after its ability to be used in warm, sunny, conditions, these installations have now, largely, fallen from favour and are increasingly uncommon.

Field hockey

For more details on this topic, see field hockey history.

The introduction of synthetic surfaces has significantly changed the sport of field hockey. Since being introduced in the 1970s, competitions in western countries are now mostly played on artificial surfaces. This has increased the speed of the game considerably, and changed the shape of hockey sticks to allow for different techniques, such as reverse stick trapping and hitting. Due to the cost of synthetic pitch installation, India and Pakistan have lost their once dominant position in international competition.

Field hockey artificial turf differs from soccer and football artificial turf in the way that it does not try to reproduce a grass 'feel', being made of shorter fibres similar to the ones used on Dunfermline's pitch. This shorter fibre structure allows the improvement in speed brought by earlier artificial turfs to be retained. This development in the game is however problematic for many local communities who often cannot afford to build two artificial pitches: one for field hockey and one for other sports. The FIH and manufacturers are driving research in order to produce new pitches that will be suitable for a variety of sports.

Pitch categories

Unfilled: Often called "water-based", the pile is unfilled. The pitches require wetting, hence the name "water-based", often via prolonged showering with pitch-side water cannon prior to their use and occasionally during half-time intervals depending on the prevailing atmospherics. They are favoured by most sports since they offer more protection for players by minimising the abrasive effect created by the sand. These pitches form the majority of the elite level field hockey pitches in use today.

· Sand-dressed: The pile of the carpet is filled to within 5-8 mm of the tips of the fibre with fine sand. The sand cannot be seen. It can be confused with unfilled pitches.

Sand filled: The pile of the carpet is filled almost to the top with sand. The sand makes the pitch rough and harder. In comparison to water-based pitches or minimal sand-dressed pitches, ball speed across the surface is often noticeably slower.

Tennis

grass court

Grass court

Roger Federer playing on the grass court (centre court) at the 2006 Wimbledon Championships

Tennis portal

A grass court is one of the four different types of tennis court. Grass courts are made of rye grass in different compositions depending on the tournament. Wimbledon with 100 percent rye grass is considered to be slower than other grass courts such as Queen's in London, and 's-Hertogenbosch in the Netherlands.

Although more traditional than other types of tennis courts, maintenance costs of grass courts are higher than those of hard courts and clay courts. Grass courts need to be reseeded every year, and (in the absence of suitable covers) must be left for the day if rain appears as the grass becomes very slippery when wet.

Grass courts are most common in England, although there are still a few others remaining elsewhere in the world.

Play

Because the court is often slippery, the ball often skids and bounces low, rarely rising above knee height, while retaining most of its speed and in addition there are often bad bounces. Therefore players must reach the ball faster and as a result the fast, low bounces keep the rallies short therefore power is rewarded on grass. As a result on grass the serve and return plays a huge part in determining the outcome of the point, so it is very important to hold serve. Since points tend to be short, it is important to keep good focus because any lapse of concentration can lead to a service break.

Consequently, most grass courts heavily favour serve and volleyers who are more aggressive and willing to sacrifice points in order for more winners overall. Serve and volleyers make it a target to finish the points off quickly and allow the ball to bounce as little as possible on their side of the net. Serve and volley players take advantage of the surface by serving the ball (usually a slice serve because of its effectiveness on grass) and then running to the net to cut off the return of serve, leaving their opponent with little time to reach the low-bouncing, fast moving ball. Therefore it's important to move in after the serve or the short/mid-court ball and win the point with a volley or overhead. In addition players often hit flatter shots to increase power and allow the ball to travel faster after and before the ball hits the ground. However, Wimbledon, the most prestigious grass tournament, has slowed down it grass courts as early as 2001 with players stating that the courts of Wimbledon have become slower, heavier, and high bouncing ^[1]. In 2001, organizes at Wimbledon had changed the grass to 100% perrenial rye in addition to changing to a harder and denser soil which resultd in a higher bounce to the ball. Grass specialist, Tim Henman, voiced out against this change in 2002 by stating, "What on earth is going on here? I'm on a grass court and it's the slowest court I've played on this year" ^[2]. As a result, baseline play has become a preferred approach at Wimbledon as opposed to the serve and volley of the past.

Movement on grass courts is somewhat different to movement on any other surface. Even the way one's foot lands on grass which is a light dab, is rather different than the full-weight landing and sliding as one does on clay. Also the slipperiness demands using a lot of small adjustment steps to get in to the correct position. You will probably need to lower your centre of gravity to get down to the low or bad bounce. However playing on grass is easier on the knees due to a natural surface, but you cannot slide as you can on clay. Quick adjustments in the swing pattern and footwork are constantly needed so any movement or co-ordination weaknesses will show up immediately. In addition most grass court players also succeed on hardcourts, although there are some exceptions.

Players

The most successful male player currently is Roger Federer, a five-time Wimbledon singles champion. His variety in the shots, speed, footwork and slices are his biggest weapons. Before being beaten in 2008 at Wimbledon by Rafael Nadal, Federer had a 65 match winning streak on Grass, and 40 consecutive wins at Wimbledon alone.

Historically, there have been three outstanding grass players, Roger Federer, Pete Sampras, and Bjorn Borg. All have won at least 5 Wimbledon championships, whereas Sampras won 7. Other players who have also been relatively successful at Wimbledon are John McEnroe, Boris Becker, Stefan Edberg,Jimmy Connors and Venus Williams.

Professional tournaments played on grass

Grand Slam

Wimbledon (London, UK)

· ATP

Artois Championship (London, Queen's Club, UK)

Gerry Weber Open (Halle, Germany)

Ordina Open ('s-Hertogenbosch, Netherlands)

Nottingham Open (Nottingham, UK) - From 2009, will be discontinued from the ATP Tour and replaced with the Eastbourne event

Campbell's Hall of Fame Tennis Championships (Newport, Rhode Island, USA)

WTA

DFS Classic (Edgbaston, Birmingham, UK)

International Women's Open (Eastbourne, England, UK)

Ordina Open ('s-Hertogenbosch, Netherlands)

 

Landscaping

Since the early 1990s, the use of synthetic grass has moved rapidly beyond athletic fields to residential and commercial landscaping artificial lawns. The idea to use synthetic grass for residential landscaping can be traced back to a Las Vegas based company named Envy Turf. Lyle Johnston, the owner of Envy Turf, saw a golf course being converted to synthetic turf, and decided it had an appropriate use in landscaping, due to the drought conditions Las Vegas has been under since the early nineties. He began purchasing and installing turf in 1992. This trend has been driven primarily by two functions: the quality and variety of synthetic grasses that are available has improved dramatically, and cities and water conservation organizations have begun realizing the value of artificial grass as a conservation measure.

Advantages and disadvantages

Advantages

· Artificial turf can be a better solution when the environment is particularly hostile to natural grass. An arid environment or one where there is little natural light are examples.

· Ideal for holiday homes when maintenance of lawns is not practical. It is also a solution for elderly homeowners who find the upkeep of lawns too much hard work.

· Suitable for roof gardens and swimming pool surrounds.

· Artificial turf pitches can last up to ten years.

Some artificial turf systems allow for the integration of fiber-optic fibers into the turf. This would allow for lighting or advertisements to be directly embedded in a playing surface, or runway lighting to be embedded in artificial landing surfaces for aircraft.^[8]

Disadvantages

The abrasions caused by artificial turf have been linked to a higher incidence of MRSA infections ^[9].

Methicillin-resistant Staphylococcus aureus

 

Methicillin-resistant Staphylococcus aureus

Electron micrograph of MRSA

Scientific classification

Domain: Bacteria Kingdom: Bacteria Phylum: Firmicutes Class: Bacilli Order: Bacillales Family: Staphylococcaceae Genus: Staphylococcus Species: S. aureus

Binomial name

Staphylococcus aureus Rosenbach 1884

Methicillin-resistant Staphylococcus aureus (MRSA, often pronounced "mersa") is a bacterium responsible for difficult-to-treat infections in humans. It may also be referred to as multiple-resistant Staphylococcus aureus or oxacillin-resistant Staphylococcus aureus (ORSA). MRSA is by definition a strain of Staphylococcus aureus that is resistant to a large group of antibiotics called the beta-lactams, which include the penicillins and the cephalosporins.

The organism is often sub-categorized as Community-Associated MRSA (CA-MRSA) or Health Care-Associated MRSA (HA-MRSA) although this distinction is complex. Some have defined CA-MRSA by criteria related to patients suffering from an MRSA infection while other authors have defined CA-MRSA by genetic characteristics of the bacteria themselves. CA-MRSA strains were first reported in the late 1990s; these cases were defined by a lack of exposure to the health care setting. In the next several years, it became clear that CA-MRSA infections were caused by strains of MRSA that differed from the older and better studied healthcare-associated strains.^[1] The new CA-MRSA strains have rapidly spread in the United States to become the most common cause of cultured skin infections among individuals seeking medical care for these infections at emergency rooms in cities. These strains also commonly cause skin infections in athletes, jail and prison detainees, soldiers, Native Alaskans and Native Americans, and children in the inner city.

MRSA is a resistant variation of the common bacterium Staphylococcus aureus. It has evolved an ability to survive treatment with beta-lactamase resistant beta-lactam antibiotics, including methicillin, dicloxacillin, nafcillin, and oxacillin. MRSA is especially troublesome in hospital-associated (nosocomial) infections. In hospitals, patients with open wounds, invasive devices, and weakened immune systems are at greater risk for infection than the general public. Hospital staff who do not follow proper sanitary procedures may transfer bacteria from patient to patient. Visitors to patients with MRSA infections or MRSA colonization are advised to follow hospital isolation protocol by using the provided gloves, gowns, and masks if indicated. Visitors who do not follow such protocols are capable of spreading the bacteria to cafeterias, bathrooms, and elevators.

Discovery and history

MRSA/Multidrug Resistant Staphylococcus aureus was discovered in 1961 in the United Kingdom. It is now found worldwide. MRSA is often referred to in the press as a "superbug."

In the past decade or so the number of MRSA infections in the United States has increased significantly. A 2007 report in Emerging Infectious Diseases, a publication of the Centers for Disease Control and Prevention (CDC), estimated that the number of MRSA infections treated in hospitals doubled nationwide, from approximately 127,000 in 1999 to 278,000 in 2005, while at the same time deaths increased from 11,000 to more than 17,000.^[2] Another study led by the CDC and published in the October 17, 2007 issue of the Journal of the American Medical Association estimated that MRSA would have been responsible for 94,360 serious infections and associated with 18,650 hospital stay-related deaths in the United States in 2005.^[3][4] These figures suggest that MRSA infections are responsible for more deaths in the U.S. each year than AIDS.^[5]

The UK Office for National Statistics reported 1,629 MRSA-related deaths in England and Wales during 2005, indicating a MRSA-related mortality rate half the rate of that in the United States for 2005, even though the figures from the British source were explained to be high because of "improved levels of reporting, possibly brought about by the continued high public profile of the disease"^[6] during the time of the 2005 United Kingdom General Election. MRSA is thought to have caused 1,652 deaths in 2006 in UK up from 51 in 1993.^[7]

It has been argued that the observed increased mortality among MRSA-infected patients may be the result of the increased underlying morbidity of these patients. Several studies, however, including one by Blot and colleagues, that have adjusted for underlying disease still found MRSA bacteremia to have a higher attributable mortality than methicillin-susceptible Staphylococcus aureus (MSSA) bacteremia.^[8]

While the statistics suggest a national epidemic growing out of control, it has been difficult to quantify the degree of morbidity and mortality attributable to MRSA. A population-based study of the incidence of MRSA infections in San Francisco during 2004-5 demonstrated that nearly 1 in 300 residents suffered from such an infection in the course of a year and that greater than 85% of these infections occurred outside of the health care setting.^[9] A 2004 study showed that patients in the United States with S. aureus infection had, on average, three times the length of hospital stay (14.3 vs. 4.5 days), incurred three times the total cost ($48,824 vs $14,141), and experienced five times the risk of in-hospital death (11.2% vs 2.3%) than patients without this infection.^[10] In a meta-analysis of 31 studies, Cosgrove et al,^[11] concluded that MRSA bacteremia is associated with increased mortality as compared with MSSA bacteremia (odds ratio = 1.93; 95% CI = 1.93±0.39).^[12] In addition, Wyllie et al. report a death rate of 34% within 30 days among patients infected with MRSA, a rate similar to the death rate of 27% seen among MSSA-infected patients.^[13]

Clinical presentation and concerns

S. aureus most commonly colonizes the anterior nares (the nostrils), although the respiratory tract, opened wounds, intravenous catheters, and urinary tract are also potential sites for infection. Healthy individuals may carry MRSA asymptomatically for periods ranging from a few weeks to many years. Patients with compromised immune systems are at a significantly greater risk of symptomatic secondary infection.

MRSA can be detected by swabbing the nostrils of patients and isolating the bacteria found inside. Combined with extra sanitary measures for those in contact with infected patients, screening patients admitted to hospitals has been found to be effective in minimizing the spread of MRSA at the Veterans Affairs hospital in Pittsburgh^[14] and in hospitals in Denmark, Finland, and the Netherlands.^[15]

The initial presentation of MRSA is small red bumps that resemble pimples, spider bites, or boils that may be accompanied by fever and occasionally rashes. Within a few days the bumps become larger, painful and eventually open into deep, pus-filled boils.^[16] About 75 percent of CA-MRSA infections are localized to skin and soft tissue and usually can be treated effectively; however CA-MRSA strains display enhanced virulence, spreading more rapidly and causing illness much more severe than traditional HA-MRSA infections, and they can affect vital organs and lead to widespread infection (sepsis), toxic shock syndrome and necrotizing ("flesh-eating") pneumonia. This is thought to be due to toxins carried by CA-MRSA strains, such as PVL and PSM. It is not known why some healthy people develop CA-MRSA skin infections that are treatable whereas others infected with the same strain develop severe infections or die.^[17]

CA-MRSA often results in abscess formation that requires incision and drainage. Before the spread of MRSA into the community, abscesses were not considered contagious because it was assumed that infection required violation of skin integrity and the introduction of staphylococci from normal skin colonization. However, newly emerging CA-MRSA is transmissible (similar, but with very important differences) from Hospital-Associated MRSA. CA-MRSA is less likely than other forms of MRSA to cause cellulitis.

Both CA-MRSA and HA-MRSA are resistant to traditional anti-staphylococcal beta-lactam antibiotics, such as cephalexin. CA-MRSA has a greater spectrum of antimicrobial susceptibility, including to sulfa drugs, tetracyclines, and clindamycin. HA-MRSA is resistant even to these antibiotics and often is susceptible only to vancomycin. Newer drugs, such as linezolid (belonging to the newer oxazolidinones class), may be effective against both CA-MRSA and HA-MRSA.

Vancomycin and teicoplanin are glycopeptide antibiotics used to treat MRSA infections.^[18] Teicoplanin is a structural congener of vancomycin that has a similar activity spectrum but a longer half-life (t½).^[19] Because the oral absorption of vancomycin and teicoplanin is very low, these agents must be administered intravenously to control systemic infections.^[20] Treatment of MRSA infection with vancomycin can be complicated, due to its inconvenient route of administration. Moreover, many clinicians believe that the efficacy of vancomycin against MRSA is inferior to that of anti-staphylococcal beta-lactam antibiotics against MSSA.^[21][22]

Several newly discovered strains of MRSA show antibiotic resistance even to vancomycin and teicoplanin. These new evolutions of the MRSA bacterium have been dubbed vancomycin intermediate-resistant Staphylococcus aureus (VISA).^[23][24] Linezolid, quinupristin/dalfopristin, daptomycin, and tigecycline are used to treat more severe infections that do not respond to glycopeptides such as vancomycin.^[25] MRSA infections can be treated with oral agents, including linezolid, rifampicin+fusidic acid, rifampicin+fluoroquinolone, pristinamycin, co-trimoxazole (trimethoprim-sulfamethoxazole), doxycycline or minocycline, and clindamycin.^[26]

On May 18, 2006, a report in Nature identified a new antibiotic, called platensimycin, that had demonstrated successful use against MRSA.^[27][28]

An entirely different and promising approach is phage therapy (e.g., at the Eliava Institute in Georgia^[29]), which has a reported efficacy against up to 95% of tested Staphylococcus isolates.^[30]

It has been reported that maggot therapy to treat MRSA infection has been successful. Studies in diabetic patients reported significantly shorter treatment times than those achieved with standard treatments.^[31][32][33]

In June 2008, researchers at the University of East London reported success in treating MRSA patients with a combination of pills and creams derived from garlic.^{[citation needed]}

At-risk populations

Inmates in prisons and Jails

In confined environments, like jails and prisons, with the rotating in and out of a new population that is typically in poor health, there have been a growing number of challenges reported first in the U. S. and then in Canada. The earliest reports were made by the U. S. Centers for Disease Control and Prevention (CDC) in state prisons in Georgia and Mississippi (MMWR). Subsequently reports of a massive rise in skin and soft tissue infections were reported by the CDC in the Los Angeles County Jail system in 2001, and this has continued. Pan et al. reported on the changing epidemiology of MRSA skin infection in the San Francisco County Jail, noting the MRSA accounted for >70% of S. aureus infection in the jail by 2002. Lowy and colleagues reported on frequent MRSA skin infections in New York State Prisons. Two reports on inmates in Maryland have demonstrated frequent colonization with MRSA. In the news media hundreds of reports of MRSA outbreaks in incarcerations facilities appeared between 2000 and 2008. For example, in February 2008, The Tulsa County Jail in the U.S. State of Oklahoma started treating an average of twelve Staphylococcus cases per month.^[34] A report on skin and soft tissue infections in the Cook County Jail in Chicago in 2004-5 demonstrated that MRSA was the most common cause of these infections among cultured lesions and furthermore that few risk factors were more strongly associated with MRSA infections than infections caused by methicillin-susceptible S. aureus. In response to these and many other reports on MRSA infections among incarcerated and recently incarcerated persons, the Federal Bureau of Prisons has released Guidelines for the management and control of the infections although few studies provide an evidence base for these guidelines.

Cystic fibrosis patients

Cystic fibrosis patients are at particular risk for pulmonary colonization of MRSA, both because of their difficulty clearing mucus and their frequent hospital visits, which can increase exposure to MRSA. These factors substantially increase the rate of life-threatening MRSA pneumonia in this group. The risk of cross-colonization has led to the increased use of isolation protocols among these patients. In a hospital setting, patients who have received fluoroquinolones are more likely to become colonized with MRSA;^[35] this is probably because many circulating strains of MRSA are fluoroquinolone resistant, which means that MRSA is able to colonize patients whose normal skin flora have been cleared of non-resistant S. aureus by fluoroquinolones.

Hospital patients

MRSA infections occur mostly in hospitals and healthcare facilities, with a higher incident rate in nursing homes or long-term care facilities. Healthcare provider to patient transfer is common, especially when healthcare providers move from patient to patient without performing necessary handwashing techniques between patients. However, it should be noted that MRSA can cause infections outside of hospitals as well.

Prevention and infection-control strategies

Screening programs

Patient screening upon hospital admission, with nasal cultures, prevents the cohabitation of MRSA carriers with non-carriers, and exposure to infected surfaces. In the United States and Canada, the Centers for Disease Control and Prevention issued guidelines on October 19, 2006, citing the need for additional research, but declined to recommend such screening.^[36][37]

A report in the journal "Pediatrics" says 2.4% of healthy children may be carrying the staph infection "MRSA" in their nasal passage.^[38]

Surface sanitizing

UK National Health Service Clean Your Hands campaign alcohol-based hand rubs

NAV-CO2 sanitizing in Pennsylvania hospital exam room

Alcohol has been proven to be an effective surface sanitizer against MRSA. Quaternary ammonium can be used in conjunction with alcohol to extend the longevity of the sanitizing action.^[39] The prevention of nosocomial infections involves routine and terminal cleaning. Non-flammable Alcohol Vapor in Carbon Dioxide systems (NAV-CO2) do not corrode metals or plastics used in medical environments and do not contribute to antibacterial resistance.

In healthcare environments, MRSA can survive on surfaces and fabrics, including privacy curtains or garments worn by care providers. Complete surface sanitation is necessary to eliminate MRSA in areas where patients are recovering from invasive procedures. Testing patients for MRSA upon admission, isolating MRSA-positive patients, decolonization of MRSA-positive patients, and terminal cleaning of patients' rooms and all other clinical areas they occupy is the current best practice protocol for nosocomial MRSA.

Hand washing

At the end of August 2004, after a successful pilot scheme to tackle MRSA, the UK National Health Service announced its Clean Your Hands campaign. Wards were required to ensure that alcohol-based hand rubs are placed near all beds so that staff can hand wash more regularly. It is thought that if this cuts infection by just 1%, the plan will pay for itself many times over.

A June 2008 report, centered on a survey by the Association for Professionals in Infection Control and Epimedmiology, concluded that poor hygiene habits remain the principal barrier to significant reductions in the spread of MRSA.

Decolonization

After the drainage of boils or other treatment for MRSA, patients can shower at home using chlorhexidine (Hibiclens) or hexachlorophene (Phisohex) antiseptic soap from head to toe, and apply mupirocin (Bactroban) 2% ointment inside each nostril twice daily for 7 days, using a cotton-tipped swab. Doctors may also prescribe strong antibiotics such as Clindamycin or Levofloxacin. Household members are recommended to follow the same decolonization protocol.

More information

Mathematical models describe one way in which a loss of infection control can occur after measures for screening and isolation seem to be effective for years, as happened in the UK. In the "search and destroy" strategy that was employed by all UK hospitals until the mid 1990s, all patients with MRSA were immediately isolated, and all staff were screened for MRSA and were prevented from working until they had completed a course of eradication therapy that was proven to work. Loss of control occurs because colonised patients are discharged back into the community and then readmitted: when the number of colonised patients in the community reaches a certain threshold, the "search and destroy" strategy is overwhelmed.^[40] One of the few countries not to have been overwhelmed by MRSA is the Netherlands: an important part of the success of the Dutch strategy may have been to attempt eradication of carriage upon discharge from hospital.^[41]

Current US guidance does not require workers in general workplaces (not healthcare facilities) with MRSA infections to be routinely excluded from going to work.^[42]

Unless directed by a healthcare provider, exclusion from work should be reserved for those with wound drainage that cannot be covered and contained with a clean, dry bandage and for those who cannot maintain good hygiene practices.^[42] Workers with active infections should be excluded from activities where skin-to-skin contact is likely to occur until their infections are healed. Healthcare workers should follow the Centers for Disease Control and Prevention's Guidelines for Infection Control in Health Care Personnel.^[43]

To prevent the spread of staph or MRSA in the workplace, employers should ensure the availability of adequate facilities and supplies that encourage workers to practice good hygiene; that surface sanitizing in the workplace is followed; and that contaminated equipment are sanitized with Environmental Protection Agency (EPA)-registered disinfectants.^[42]

Reports reflect a nationwide epidemic of MRSA in the US — one that has significantly increased over the past seven years. A 2007 report in Emerging Infectious Diseases, a publication of the Centers for Disease Control and Prevention, estimated that the number of MRSA infections treated in hospitals doubled nationwide, from approximately 127,000 in 1999 to 278,000 in 2005, while at the same time deaths increased from 11,000 to more than 17,000.^[2]

Worldwide, an estimated 2 billion people carry some form of S. aureus; of these, up to 53 million (2.7% of carriers) are thought to carry MRSA.^[44] In the United States, 95 million carry S. aureus in their noses; of these, 2.5 million (2.6% of carriers) carry MRSA.^[45] A population review conducted in three U.S. communities showed the annual incidence of CA-MRSA during 2001–2002 to be 18–25.7/100,000; most CA-MRSA isolates were associated with clinically relevant infections, and 23% of patients required hospitalization.^[46]

In the United States, there have been increasing numbers of reports of outbreaks of MRSA colonization and infection through skin contact in locker rooms and gymnasiums, even among healthy populations. A study published in the New England Journal of Medicine^[47] linked MRSA to the abrasions caused by artificial turf. Three studies by the Texas State Department of Health found that the infection rate among football players was 16 times the national average. In December 2007, a high school football player died from MRSA-infected turf burns.^[48] MRSA has also been found in the public school systems throughout the country.^[49]

MRSA is also becoming a problem in pediatric settings,^[50] including hospital nurseries.^[51] A 2007 study found that 4.6% of patients in U.S. health care facilities were infected or colonized with MRSA.^[52] One 2008 study concluded that men living in predominately gay ZIP codes in San Francisco are 13 times more likely to be infected by one strain of MRSA than their heterosexual neighbors.^[53]

MRSA progresses substantially within 24-48 hours of initial topical symptoms. After 72 hours, MRSA can take hold of human tissue and become resistant to treatment. MRSA causes as many as 20% of Staphylococcus aureus infections in populations that use intravenous drugs. These out-of-hospital strains, or CA-MRSA, are more easily treated, though more virulent, than HA-MRSA. CA-MRSA apparently did not evolve de novo in the community but represents a hybrid between MRSA that spread from the hospital environment and strains that were once easily treatable in the community. Most of the hybrid strains also acquired a factor that increases their virulence, resulting in the development of deep-tissue infections from minor scrapes and cuts, as well as many cases of fatal pneumonia.^[54]

As of early 2005, the number of deaths in the United Kingdom attributed to MRSA has been estimated by various sources to lie in the area of 3,000 per year.^[55] Staphylococcus bacteria account for almost half of all UK hospital infections. The issue of MRSA infections in hospitals has recently been a major political issue in the UK, playing a significant role in the debates over health policy in the United Kingdom general election held in 2005.

On January 6, 2008, half of 64 non-Chinese cases of Methicillin-resistant Staphylococus aureus (MRSA) infections in Hong Kong in 2007 were Filipino domestic helpers. Ho Pak-leung, professor of microbiology, University of Hong Kong traced the cause from high use of antibiotics. In 2007, there were 166 community cases in Hong Kong compared with 8,000 hospital-acquired MRSA (155 recorded cases — 91 involved Chinese locals, 33 Filipinos, 5 each for Americans and Indians, and 2 each from Nepal, Australia, Denmark and England).^[56]

Strains

In the UK, the most common strains of MRSA are EMRSA15 and EMRSA16.^[57] EMRSA16 is the best described epidemiologically; it originated in Kettering, England, and the full genomic sequence of this strain has been published.^[58] EMRSA16 has been found to be identical to the ST36:USA200 strain, which circulates in the United States, and to carry the SCCmec type II, enterotoxin A and toxic shock syndrome toxin 1 genes.^[59] Under the new international typing system, this strain is now called MRSA252. It is not entirely certain why this strain has become so successful, whereas previous strains have failed to persist. One explanation is the characteristic pattern of antibiotic susceptibility. Both the EMRSA15 and EMRSA16 strains are resistant to erythromycin and ciprofloxacin. It is known that Staphylococcus aureus can survive intracellularly,^[60] and these are precisely the antibiotics that best penetrate intracellularly; it may be that these strains of S. aureus are therefore able to exploit an intracellular niche.

In the United States, most cases of CA-MRSA are caused by a CC8 strain designated ST8:USA300, which carries SCCmec type IV, Panton-Valentine leukocidin, PSM-alpha and enterotoxins Q and K,^[59] and ST1:USA400.^[61] Other community-associated strains of MRSA are ST8:USA500 and ST59:USA1000. In many nations of the world, MRSA strains with different predominant genetic background types have come to predominate among CA-MRSA strains; USA300 easily tops the list in the U. S. and is becoming more common in Canada after its first appearance there in 2004. For example, in Australia ST93 strains are common, while in continental Europe ST80 strains predominate (Tristan et al., Emerging Infectious Diseases, 2006). In Taiwan, ST59 strains, some of which are resistant to many non-beta-lactam antibiotics, have arisen as common causes of skin and soft tissue infections in the community. In a remote region of Alaska, unlike most of the continental U. S., USA300 was found rarely in a study of MRSA strains from outbreaks in 1996 and 2000 as well as in surveillance from 2004-6 (David et al., Emerg Infect Dis 2008).

Laboratory diagnosis

Mueller Hinton agar showing MRSA resistant to oxacillin disk

Diagnostic microbiology laboratories and reference laboratories are key for identifying outbreaks of MRSA. New rapid techniques for the identification and characterization of MRSA have been developed. These techniques include Real-time PCR and Quantitative PCR and are increasingly being employed in clinical laboratories for the rapid detection and identification of MRSA strains.^[62][63]

See also

Contamination control

Drug resistance

· Drug resistant diseases

Vancomycin-resistant Staphylococcus aureus

MDR-TB

XDR-TB

Vancomycin-resistant enterococcus (VRE)

Clostridium difficile (CDF)

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^ ^{a b} Diep B, Carleton H, Chang R, Sensabaugh G, Perdreau-Remington F (2006). "Roles of 34 virulence genes in the evolution of hospital- and community-associated strains of methicillin-resistant Staphylococcus aureus". J Infect Dis 193 (11): 1495–503. doi:10.1086/503777. PMID 16652276. 

^ von Eiff C, Becker K, Metze D, et al. (2001). "Intracellular persistence of Staphylococcus aureus small-colony variants within keratinocytes: a cause for antibiotic treatment failure in a patient with Darier's disease". Clin Infect Dis 32 (11): 1643–7. doi:10.1086/320519. PMID 11340539. 

^ R Wang et al. "Identification of novel cytolytic peptides as key virulence determinants of community-associated MRSA". Nature Medicine DOI: 10.1038/nm1656 (2007).

^ (2008) "Rapid Diagnosis and Typing of Staphylococcus aureus", Staphylococcus: Molecular Genetics. Caister Academic Press. ISBN 978-1-904455-29-5. 

^ Mackay IM (editor). (2007). Real-Time PCR in Microbiology: From Diagnosis to Characterization. Caister Academic Press. ISBN 978-1-904455-18-9. 

 

 Further reading

Mayo recommends prevention through proper hand-washing technique

CDC Guideline "Management of Multidrug-Resistant Organisms in Healthcare Settings, 2006"

CDC Article on Hospital Associated MRSA

CDC Article on Community Associated MRSA

National Institute for Occupational Safety and Health — MRSA and the Workplace

Clinical images of MRSA and associated diseases

Flesh-eating bug spreads among gays

·  

Some artificial turf requires infill such as silicon sand and/or granulated rubber made from recycled car tires. This material may carry heavy metals which can leach into the water table.^[10]

Periodic disinfection is required as pathogens are not broken down by natural processes in the same manner as natural turf. Despite this, recent studies suggest certain microbial life is less active.^[11]

Turf toe is a medical condition which is often associated with playing on artificial turf pitches.

Friction between skin and artificial turf causes abrasions and/or burns to a much greater extent than natural grass.^[11] This is an issue for some sports: for example, football in which sliding maneuvers are common and clothing does not fully cover the limbs. However, with some third-generation artificial grasses, this is almost completely eliminated by the use of polyethylene yarn.

Artificial turf tends to be much hotter than natural grass when exposed to the sun.^[12]

Many players claim that the lack of "give" in artificial turf leads to strain and injury in the legs, especially amongst players used to playing on natural grass. Some players refuse to play on artificial turf, and there have been cases of players not signing with a particular team for fear of damaging their legs by playing on artificial turf.^{[citation needed]}

See also

List of brands of artificial turf

AstroTurf

FieldTurf

Artificial ski slopes

References

^ ^{a b} Lawton, Graham (04 June 2005). "Pitch battle over artificial grass". New Scientist (2502): p.35. Retrieved on 2008-01-11. 

^ Salzburg turf approval at UEFA.com

^ Approval for artificial pitches at UEFA.com

^ . "LigaTurf 250 ACS 75 / /RPU Data Sheet" (PDF). Polytan Sportstättenbau GmbH. Retrieved on 2008-01-11.

^ "England to play on synthetic turf", BBC News (2007-07-11). Retrieved on 2008-01-11. 

^ "Pitch 'No Excuse' For England", Sporting Life UK. Retrieved on 2008-01-11. 

^ Martyn Ziegler (2007-10-10). "England could slip up on plastic pitch, warns Ferguson". The Independent. Retrieved on 2008-01-11.

^ Monte Burke (2006-11-27). "Field of Screens", Forbes. Retrieved on 2008-01-11. 

^ New England Journal of Medicine article

^ David R. Brown, Sc.D.. "Artificial Turf" (.PDF). Environment & Human Health, Inc. Retrieved on 2008-01-11.

^ ^{a b} Penn State College of Agricultural Sciences (30 August 2006). "New Penn State Study Debunks Staph Bacteria Scare In Synthetic Turf". Press release. Retrieved on 2008-01-11.

^ C. Frank Williams, Gilbert E. Pulley. "Synthetic Surface Heat Studies" (.PDF). Brigham Young University. Retrieved on 2008-02-19.

External links

Installation of Artificial Turf Visual step by step instructions of the installation of artificial turf.

[1] This site is for artificial turf contractors

Turf toe, a general introduction

Use of rubber and environmental considerations. This article discusses new technology which is planned to mitigate some of the problems of using recycled car tyres (tires). It also quantifies the amount of rubber on a typical pitch as 100 tons or 22,000 old car tyres.

Rubber pollution in a domestic environment. This article looks at the impact of rubber crumb on a domestic environment.

Artificial Turf for Football : a technical overview 2007

Artificial Turf for Football : Testing and Requirements FIFA-EN-DIN; an Overview 2007

FIFA Football Turf

English Football Association guidelines for choosing artificial grass pitches

List of the major synthetic turf benefitsArtificial ski turf

Artificial turf for ski

Retrieved from "http://en.wikipedia.org/wiki/Artificial_turf"

Categories: Artificial turf | Gardening | Plastics applications | Recyclable materials | Water conservation

Hidden categories: Wikipedia articles in need of updating | All articles with unsourced statements | Articles with unsourced statements since April 2008

 

Natural rubber

This article is about the polymeric material natural rubber.

For man-made rubber materials, see Synthetic rubber. For other uses, see Rubber (disambiguation).

Latex being collected from a tapped rubber tree

Natural rubber is an elastomer—an elastic hydrocarbon polymer—that was originally derived from a a milky colloidal suspension, or latex, found in the sap of some plants. The purefied form of natural rubber is the chemical polyisoprene which can also be produced synthetically. Natural rubber is used extensively in many applications and products. The entropy model of rubber was developed in 1934 by Werner Kuhn.

Varieties

The major commercial source of natural rubber latex is the Para rubber tree, Hevea brasiliensis (Euphorbiaceae). This is largely because it responds to wounding by producing more latex.

Other plants containing latex include figs (Ficus elastica), Castilla (Panama rubber tree), euphorbias, lettuce, the common dandelion, Taraxacum kok-saghyz (Russian dandelion), Scorzonera tau-saghyz, and Guayule. Although these have not been major sources of rubber, Germany attempted to use some of these during World War II when it was cut off from rubber supplies^{[citation needed]}. These attempts were later supplanted by the development of synthetic rubbers. To distinguish the tree-obtained version of natural rubber from the synthetic version, the term gum rubber is sometimes used.

Discovery of commercial potential

Charles Marie de La Condamine is credited with introducing samples of rubber to the Académie Royale des Sciences of France in 1736.^[1] In 1751 he presented a paper by François Fresneau to the Académie (eventually published in 1755) which described many of the properties of rubber. This has been referred to as the first scientific paper on rubber.^[1]

The para rubber tree initially grew in South America, and the first European to return to Portugal from Brazil with samples of water-repellent rubberized cloth so shocked people that he was brought to court on the charge of witchcraft. When samples of rubber first arrived in England, it was observed by Joseph Priestley, in 1770, that a piece of the material was extremely good for rubbing out pencil marks on paper, hence the name "rubber".

South America remained the main source of what limited amount of latex rubber was consumed during much of the 19th century. However in 1876, Henry Wickham gathered thousands of seeds from Brazil, and these were germinated in Kew Gardens, UK. The seedlings were then sent to Ceylon (Sri Lanka), Indonesia, Singapore and British Malaya. Malaya (now Malaysia) was later to become the biggest producer of rubber. About 100 years ago, the Congo Free State in Africa was also a significant source of natural rubber latex, mostly gathered by forced labor. Liberia and Nigeria also started production of rubber.

In India commercial cultivation of natural rubber was introduced by the British Planters, although the experimental efforts to grow rubber on a commercial scale in India were initiated as early as 1873 at the Botanical Gardens, Kolkata. The first commercial Hevea plantations in India were established at Thattekadu in Kerala in 1902.

Properties

Rubber latex.

Rubber exhibits unique physical and chemical properties. Rubber's stress-strain behavior exhibits the Mullins effect, the Payne effect and is often modeled as hyperelastic. Rubber strain crystallizes.

Owing to the presence of a double bond in each and every repeat unit, natural rubber is sensitive to ozone cracking

Chemical makeup

Natural rubber is a polymer of isoprene - most often cis-1,4-polyisoprene - with a molecular weight of 100,000 to 1,000,000. Typically, a few percent of other materials, such as proteins, fatty acids, resins and inorganic materials are found in natural rubber. Polyisoprene is also created synthetically, producing what is sometimes referred to as "synthetic natural rubber".

Some natural rubber sources called gutta percha are composed of trans-1,4-polyisoprene, a structural isomer which has similar, but not identical properties.

Natural rubber is an elastomer and a thermoplastic. However, it should be noted that as the rubber is vulcanized it will turn into a thermoset. Most rubber in everyday use is vulcanized to a point where it shares properties of both; i.e., if it is heated and cooled, it is degraded but not destroyed.

Elasticity

In most elastic materials, such as metals used in springs, the elastic behavior is caused by bond distortions. When force is applied, bond lengths deviate from the (minimum energy) equilibrium and strain energy is stored electrostatically. Rubber is often assumed to behave in the same way, but it turns out this is a poor description. Rubber is a curious material because, unlike metals, strain energy is stored thermally.

In its relaxed state rubber consists of long, coiled-up polymer chains that are interlinked at a few points. Between a pair of links each monomer can rotate freely about its neighbour. This gives each section of chain leeway to assume a large number of geometries, like a very loose rope attached to a pair of fixed points. At room temperature rubber stores enough kinetic energy so that each section of chain oscillates chaotically, like the above piece of rope being shaken violently.

When rubber is stretched the "loose pieces of rope" are taut and thus no longer able to oscillate. Their kinetic energy is given off as excess heat. Therefore, the entropy decreases when going from the relaxed to the stretched state, and it increases during relaxation. This change in entropy can also be explained by the fact that a tight section of chain can fold in fewer ways (W) than a loose section of chain, at a given temperature (nb. entropy is defined as S=k*ln(W)). Relaxation of a stretched rubber band is thus driven by an increase in entropy, and the force experienced is not electrostatic, rather it is a result of the thermal energy of the material being converted to kinetic energy. Rubber relaxation is endothermic, and for this reason the force exerted by a stretched piece of rubber increases with temperature (metals, for example, become softer as temperature increases). The material undergoes adiabatic cooling during contraction. This property of rubber can easily be verified by holding a stretched rubber band to your lips and relaxing it.

Stretching of a rubber band is in some ways equivalent to the compression of an ideal gas, and relaxation is equivalent to its expansion. Note that a compressed gas also exhibits "elastic" properties, for instance inside an inflated car tire. The fact that stretching is equivalent to compression may seem somewhat counter-intuitive, but it makes sense if rubber is viewed as a one-dimensional gas. Stretching reduces the "space" available to each section of chain.

Vulcanization of rubber creates more disulfide bonds between chains so it makes each free section of chain shorter. The result is that the chains tighten more quickly for a given length of strain. This increases the elastic force constant and makes rubber harder and less extendable.

When cooled below the glass transition temperature, the quasi-fluid chain segments "freeze" into fixed geometries and the rubber abruptly loses its elastic properties, though the process is reversible. This is a property it shares with most elastomers. At very cold temperatures rubber is actually rather brittle; it will break into shards when struck or stretched. This critical temperature is the reason that winter tires use a softer version of rubber than normal tires. The failing rubber o-ring seals that contributed to the cause of the Challenger disaster were thought to have cooled below their critical temperature. The disaster happened on an unusually cold day.

Current sources

Close to 21 million tons of rubber were produced in 2005 of which around 42% was natural. Since the bulk of the rubber produced is the synthetic variety which is derived from petroleum, the price of even natural rubber is determined to a very large extent by the prevailing global price of crude oil^{[citation needed]}. Today Asia is the main source of natural rubber, accounting for around 94% of output in 2005. The three largest producing countries (Indonesia, Malaysia and Thailand) together account for around 72% of all natural rubber production.

Cultivation

Rubber is generally cultivated in large plantations. See the coconut shell used in collecting latex, in plantations in Kerala, India

Rubber latex is extracted from Rubber trees. The economic life period of rubber trees in plantations is around 32 years – 7 years of immature phase and about 25 years of productive phase.

The soil requirement of the plant is generally well-drained weathered soil consisting of laterite, lateritic types, sedimentary types, nonlateritic red or alluvial soils.

The climatic conditions for optimum growth of Rubber tree consist of (a) Rainfall of around 250 cm evenly distributed without any marked dry season and with at least 100 rainy days per annum (b) Temperature range of about 20°C to 34°C with a monthly mean of 25°C to 28°C (c) High atmospheric humidity of around 80% (d) Bright sunshine amounting to about 2000 hours per annum at the rate of 6 hours per day throughout the year and (e) Absence of strong winds.

Many high-yielding clones have been developed for commercial planting. These clones yield more than 1,500 kilograms of dry Rubber per hectare (or, over 4 tons per acre), per annum, when grown under ideal conditions.

Collection

A tree woman in Sri Lanka in the process of harvesting rubber.

In places like Kerala, where coconuts are in abundance, the shell of half a coconut is used as the collection container for the latex. The shells are attached to the tree via a short sharp stick and the latex drips down into it overnight. This usually produces latex up to a level of half to three quarters of the shell.

The latex can be either collected in its liquid state, in which case ammonia solution can be added to the collecting cup prior to tapping in order to prevent natural coagulation, or it can be left in the field to coagulate into a cup lump.

Latex is generally processed into either latex concentrate for manufacture of dipped goods or it can be coagulated under controlled, clean conditions using formic acid. The coagulated latex can then be processed into the higher grade technically specified block rubbers such as TSR3L or TSRCV or used to produce Ribbed Smoke Sheet grades.

Naturally coagulated rubber (cup lump) is used in the manufacture of TSR10 and TSR20 grade rubbers. The processing of the rubber for these grades is basically a size reduction and cleaning process in order to remove contamination and prepare the material for the final stage drying.

The dried material is then baled and palletized for shipment.

Uses

The use of rubber is widespread, ranging from household to industrial products, entering the production stream at the intermediate stage or as final products. Tires and tubes are the largest consumers of rubber, accounting for around 56% total consumption in 2005. The remaining 44% are taken up by the general rubber goods (GRG) sector, which includes all products except tires and tubes.

Other significant uses of rubber are door and window profiles, hoses, belts, matting, flooring and dampeners (anti-vibration mounts) for the automotive industry in what is known as the "under the bonnet" products. Gloves (medical, household and industrial) are also large consumers of rubber and toy balloons, although the type of rubber used is that of the concentrated latex. Significant tonnage of rubber is used as adhesives in many manufacturing industries and products, although the two most noticeable are the paper and the carpet industry. Rubber is also commonly used to make rubber bands and pencil erasers.

Additionally, rubber produced as a fiber sometimes called elastic, has significant value for use in the textile industry because of its excellent elongation and recovery properties. For these purposes, manufactured rubber fiber is made as either an extruded round fiber or rectangular fibers that are cut into strips from extruded film. Because of its low dye acceptance, feel and appearance, the rubber fiber is either covered by yarn of another fiber or directly woven with other yarns into the fabric. In the early 1900’s, for example, rubber yarns were used in foundation garments. While rubber is still used in textile manufacturing, its low tenacity limits its use in lightweight garments because latex lacks resistance to oxidizing agents and is damaged by aging, sunlight, oil, and perspiration. Seeking a way to address these shortcomings, the textile industry has turned to Neoprene (polymer form of Chloroprene), a type of synthetic rubber as well as another more commonly used elastomer fiber, spandex (also known as elastane), because of their superiority to rubber in both strength and durability.

Natural rubber is often vulcanized, a process by which the rubber is heated and sulfur, peroxide or bisphenol are added to improve resilience and elasticity, and to prevent it from perishing. Vulcanization greatly improved the durability and utility of rubber from the 1830s on. The successful development of vulcanization is most closely associated with Charles Goodyear. Carbon black is often used as an additive to rubber to improve its strength, especially in vehicle tires.

Allergic reactions

Main article: Latex allergy

Some people have a serious latex allergy, and exposure to certain natural rubber latex products such as latex gloves can cause anaphylactic shock. Guayule latex is hypoallergenic and is being researched as a substitute to the allergy-inducing Hevea latexes.

Some allergic reactions are not from the latex but from residues of other ingredients used to process the latex into clothing, gloves, foam, etc. These allergies are usually referred to as multiple chemical sensitivity (MCS).

See also

Akron, Ohio, center of the rubber industry

Charles Greville Williams, researched natural rubber being a polymer of the monomer isoprene

Elastomer

Fordlândia, failed attempt to establish a rubber plantation in Brazil

Molded rubber

Ozone cracking

Rubber tapping, the process of harvesting the rubber sap

Stevenson Plan, historical British plan to stabilise rubber prices

References

^ ^{a b} Untitled Document

· Rubbery Materials and their Compounds by J.A Brydson

Rubber Technology by Maurice Morton

Metatarsalphalangeal joint sprain

Metatarsalphalangeal joint sprain Classification and external resources
ICD-10	S93.5
ICD-9	845.12
eMedicine	orthoped/572

A metatarsalphalangeal joint sprain is an injury to the joint and connective tissue between the foot and one of the toes. When the big toe is involved, it is known as "turf toe".^[1][2]

Causes

Turf toe is named from the injury being associated with playing sports on rigid surfaces such as artificial turf^[3] and is a fairly common injury among professional American football players. Often, the injury occurs when someone or something falls on the back of the calf while that leg's knee and tips of the toes are touching the ground. The toe is hyperextended and thus the joint is injured. Additionally, athletic shoes that tend to have very flexible soles combined with cleats that "grab" the turf will cause overextension of the big toe. It should be noted that this can occur on the lesser toes as well.

Turf toe can also happen when the nail bed is forced into the cuticle and swelling with isolated pain may occur.

Treatment and prognosis

The injury can be debilitating for athletes who need to accelerate, 'cut' quickly, or jump. Use of the toes is not possible during the healing process. Since the toes are necessary for proper push-off when accelerating, those sorts of athletic activities can be almost completely curtailed. A healing period of one or more months is often required.

Because of the anatomy of the distal foot and the unique use of the foot, it is often impossible to properly tape or brace the joint. Although difficult, it is not impossible to tape the toe to limit dorsiflexion (upward bend of toe). Additionally, wearing a shoe with a rigid sole and cushioned innersole will help. Anti-inflammatory medication as well as physical therapy is recommended.

Turf toe can often progress into a chronic problem, in which the joint(s) never really heals or heals too slowly to return to usual physical activities.

Turf toe can become more serious if left untreated.

Notable cases

Deion Sanders was plagued with this injury throughout his career,^[4] with serious reductions in playing time near the end of his football career.

Astro Turf

AstroTurf

 

AstroTurf
Type	LLC
Founded	1964
Headquarters	Dalton, Georgia, USA
Key people	Bryan Peeples-President of AstroTurf, Michael Dennis-Chairman and President of GeneralSports Venue, Jon Pritchett-CEO of GeneralSports Venue
Website	http://www.astroturfusa.com/

This article is about artificial grass. For marketing and political campaigning practice, see astroturfing.

AstroTurf is a brand of artificial turf. Though the term is a registered trademark, it is sometimes used as a generic description of any kind of artificial turf. The original AstroTurf product was a short pile synthetic turf ^[1] while the current products incorporate modern features such as antimicrobial protection, rubber infill, backing systems and nylon yarn fibers.

History

AstroTurf was co-invented in 1964 by James M. Faria and Robert T. Wright, employees of Monsanto. It was patented in 1967 and originally sold under the name "Chemgrass". It was renamed AstroTurf after its first well-publicized use at the Houston Astrodome stadium in 1966.

In 1986 Monsanto consolidated its AstroTurf management, marketing, and technical activities in Dalton, Georgia, as AstroTurf Industries, Inc. In 1988 Balsam AG purchased all the capital stock of AstroTurf Industries, Inc. In 1994 Southwest Recreational Industries, Inc. (SWRI) acquired the AstroTurf brand. In 1996 SWRI was acquired by American Sports Products Group Inc. (ASPG). In 2001, SWRI launched a turf system called NexTurf.^[2] In 2003 SWRI changed its name to SRI Sports and one year later filed for bankruptcy and the parent company, ASPG, retained the AstroTurf rights. In 2005 Textile Management and Associates (TMA) acquired the AstroTurf assets and intellectual property from ASPG and began marketing the AstroTurf brand under the company AstroTurf, LLC. In 2006 GeneralSports Venue (GSV) became TMA’s marketing partner for the AstroTurf brand for the American market. AstroTurf, LLC handles the marketing of AstroTurf in the rest of the world.

Product Timelin

1960s

1964

The Moses Brown School in Providence, Rhode Island, installs AstroTurf.^[3]

1965

The Houston Astrodome opens with natural turf and a glass roof which causes glare for the fielders. The glass panes with a view of the sun are painted white, and the grass soon dies. The field's dead grass is replaced with AstroTurf the next year.

1966

AstroTurf is first installed in the Houston Astrodome. The infield was in place in April, but due to lack of supply, the outfield is not completed until July, when the Astros are sent on an extended road trip. The all-synthetic field is ready for play following the All-Star break in July. The first football game played on AstroTurf occurs when the Houston Cougars beat the Washington State Cougars.

1967

AstroTurf is first installed in an outdoor stadium - Indiana State University Stadium, Terre Haute, Indiana.^[4]

1968

AstroTurf manufacturing facility opens in Dalton, GA.^[5]

Husky Stadium at the University of Washington in Seattle becomes the second major sports facility in the U.S. to install AstroTurf.

1970s

1974

Miami Dolphins play Minnesota Vikings on AstroTurf in Super Bowl VIII – Rice Stadium, Houston, TX.^[6]

1975

AstroTurf is installed at New Orleans Louisiana Superdome^[7] and Pontiac Silverdome.^[8]

First international field hockey game played on AstroTurf at Molson Stadium, Montreal.^[9]

Cincinnati Reds play World Series on AstroTurf.^[10]

1976

Cincinnati Reds play back-to-back World Series' on AstroTurf.^[11]

1978

Dallas Cowboys defeat the Denver Broncos (27-10) on AstroTurf in Super Bowl XII – Superdome, New Orleans, LA.

1980s

1980

1980 World Series is first to be entirely played on AstroTurf as the Philadelphia Phillies (Veterans Stadium) defeat the Kansas City Royals (Royals Stadium) in six games.

1981

Oakland Raiders play Philadelphia Eagles on AstroTurf in Super Bowl XV – Superdome, New Orleans, LA. ^[12]

1983

Women's World Cup Hockey (field hockey) games are played on AstroTurf.^[13]

AstroTurf installs first North American vertical drainage systems in Ewing, NJ at Trenton State College (now known as The College of New Jersey). ^[14]

1989

First E-Layer system (Elastomeric) installed at William and Mary, as well as University of California, Berkeley. ^[15]

1990s

1993

The fourth (and thus far last) World Series to be played entirely on AstroTurf features the Toronto Blue Jays defeating the Philadelphia Phillies 4 games to 2.

1996

Atlanta Olympic Field Hockey installs AstroTurf System.^[16]

1999

Real Madrid C. F. (Spain) become the first European football club to purchase an AstroTurf system for their practice fields.^[17]

2000s

2002

Buffalo Bills install AstroTurf system in Ralph Wilson Stadium.^[18]

 See also

Artificial turf

Astroturfing

List of AstroTurf installations

References

^ US patent 3332828

^ Breaking the surface: uncovering your sports surfacing needs | Coach and Athletic Director | Find Articles at BNET.com

^ Topic Galleries - baltimoresun.com

^ [1]

^ AstroTurf | About | History

^ FOX Sports on MSN - AstroTurf Turf Talk - Turf Talk

^ The Biggest Dome - TIME

^ Stadiums of the NFL-Silverdome-Detroit Lions

^ Percival Molson Memorial Stadium

^ 1975 World Series by Baseball Almanac

^ 1976 World Series by Baseball Almanac

^ Stadiums of the NFL-Superdome-Super Bowl XII, XV, XX, XXIV, XXXI, XXXVI

^ The Sunday Tribune - Spectrum

^ The College of New Jersey Athletics - Lions' Stadium

^ Marshall Press Release

^ Panstadia VOL 3/No 4 - 'OUT WITH THE OLD'

^ News & Events - SRI Sports - International - Field, Track, Indoor, Tennis Systems & Services

Field Turf

FieldTurf

The wide plain of FieldTurf used at Toronto's Rogers Centre was installed after the 2004 baseball season.

FieldTurf Tarkett, a division of Tarkett Inc., is a Peachtree City, GA-based company that manufactures and installs artificial turf playing surfaces identified by the FieldTurf trademark ^[1].

Product

FieldTurf is an artificial turf composed of monofilament polyethylene blend fibres tufted into a polypropylene backing with a mixture of silica sand and cryogenic rubber infill. FieldTurf was first patented in 1982.

Notable installations

See List of FieldTurf installations for more installations.

In 1999 Memorial Stadium at the University of Nebraska in Lincoln, Nebraska (the first college-only football stadium to use FieldTurf in 1999), plus these other facilities at the school:

· Ed Weir Track infield

· Hawks Championship Indoor Center - Nebraska Cornhuskers training facility

· Cook Pavilion - Nebraska Cornhuskers training facility and university campus recreation facility

Vine Street Fields - University Campus Recreation intramural fields

In 1999, the Metropolitan Oval, a soccer complex in New York City, was one of the first to install FieldTurf in the U.S.

In March 2000, FieldTurf replaced the original AstroTurf field at Tropicana Field, making the Tampa Bay Rays of Major League Baseball the first professional sports team to play on the FieldTurf surface.

In 2000, FieldTurf was installed in the University of Washington's Husky Stadium, replacing the AstroTurf surface, originally installed in 1968. Husky Stadium was used as the Seattle Seahawks home field from 2000-2001, following the demolition of the Kingdome in March 2000. This would be the first FieldTurf used in the NFL.

In 2005, Saprissa Stadium in San José, Costa Rica became the first stadium to host a FIFA World Cup qualifying match on FieldTurf.

In 2007, the FIFA U-20 World Cup Canada had almost 50% of its games played on FieldTurf ^[2].

As of 2007, seven of the eight Canadian Football League teams have installed either FieldTurf or a similar surface.

The University of Saskatchewan installed it in 2006 when they hosted the Vanier Cup.

Currently all but three National Football League venues have either FieldTurf or natural grass surfaces.

Super Bowl XL, featuring the Seattle Seahawks and the Pittsburgh Steelers, was the first time that the Super Bowl has been played on FieldTurf. The Ford Field installation differs slightly from the standard installation as the recycled rubber used is made from Firestone tires.^[3]

Criticism

In September 2006, several top Canadian soccer players appealed to the Canadian Soccer Association to install a natural grass surface at BMO Field in Toronto.^[4] The Association has, however, decided to install FieldTurf despite the players' request.

In addition, following David Beckham's move to Major League Soccer in 2007, in which he arrived carrying an ankle injury,