A swimming pool , swimming bath , wading pool , or simply a pool , is an artificially enclosed body of water intended for swimming or water-based recreation. There are many standard sizes; the largest and deepest is the Olympic size. A pool can be built either above or in the ground, and from materials such as metal, plastic, fiberglass or concrete.

Pools that may be used by many people or by the general public are called public, while pools used exclusively by a few people or in a home are called private. Many health clubs, fitness centers and private clubs have public pools used mostly for exercise. Many hotels and massage parlors have public pools for relaxation. Hot tubs and spas are pools with hot water, used for relaxation or therapy, and are common in homes, hotels, clubs and massage parlors. Swimming pools are also used for diving, other sports, and training of lifeguards and astronauts.

Pools must be sanitized to prevent growth and spread of bacteria, viruses, algae and insect larvae that can cause disease. This is done by chemical disinfectants such as chlorine, bromine or mineral sanitizers, and additional filters. Alternatively, pools can be made without chemical disinfectants by using a biofilter with additional filters. In both cases, pools need to be fitted with an adequate flow rate.

History

The "great bath" at the site of Mohenjo-Daro was most likely dug during the 3rd millennium BC. This pool is 12 by 7 meters, is lined with bricks and was covered with a tar-based sealant.

Ancient Greeks and Romans built artificial pools for athletic training in the palaestras, for nautical games and for military exercises. Roman emperors had private swimming pools in which fish were also kept, hence one of the Latin words for a pool, piscina. The first heated swimming pool was built by Gaius Maecenas of Rome in the first century BC. Gaius Maecenas was a rich Roman lord and considered one of the first patrons of arts.

Ancient Sinhalese built pairs of pools called "Kuttam Pokuna" in the kingdom of Anuradhapura, Sri Lanka in the 4th century BC. They were decorated with flights of steps, punkalas or pots of abundance and scroll design.

Swimming pools became popular in Britain in the mid 19th century. By 1837, six indoor pools with diving boards were built in London, England. After the modern Olympic Games began in 1896 and included swimming races, the popularity of swimming pools began to spread (reference: Encyclopedia Britannica). In 1839, Oxford had its first major public indoor pool at Temple Cowley, and swimming began to take off. The Amateur Swimming Association was founded in 1869 in England, and the Oxford Swimming Club in 1909 with its home at Temple Cowley Pool. The presence of indoor baths in the cobbled area of Merton Street, London may have persuaded the less hardy of the aquatic brigade to join. So, bathers gradually became swimmers, and bathing pools swimming pools.

In the USA, the Racquet Club of Philadelphia clubhouse (1907) boasts one of the world's first modern above-ground swimming pools. The first swimming pool to go to sea on an ocean liner was installed on the White Star Line's Adriatic in 1907.

After World War I and the departure of "long John" style swimming costumes, interest in competitive swimming grew. Standards improved and training became essential.

Home swimming pools became popular in the USA after World War II and the publicity given to swimming sports by Hollywood films like Esther Williams Million Dollar Mermaid made a home pool a desirable status symbol. More than 50 years later, the home or residential swimming pool is ubiquitous and even small nations enjoy a thriving swimming pool industry (e.g. New Zealand pop. 4,116,900 - holds the record in pools per capita with 65,000 home swimming pools and 125,000 spa pools).

Swimming pool records

One of the largest swimming pools ever built was reputedly in Moscow after the Palace of Soviets remained uncompleted. The foundations were converted into the Moskva Pool open air swimming pool after the process of de-Stalinisation. After the fall of communism, Christ the Saviour Cathedral was re-built (it had originally been on the site) between 1995 and 2000.

According to the Guinness World Records, the largest swimming pool in the world is San Alfonso del Mar Seawater pool in Algarrobo, Chile. It is 1,013 m (3,320 ft) long and has an area of 8 ha (20 acres). It was completed in December 2006.

The largest indoor wave pool in North America is at the West Edmonton Mall and the largest indoor pool is at the Neutral Buoyancy Lab in the Sonny Carter Training Facility at NASA JSC in Houston. The recreational diving center Nemo 33 near Brussels, Belgium is home to the world's deepest swimming pool. The pool has two large flat-bottomed areas at depth levels of 5 m (16 ft) and 10 m (33 ft), and a large circular pit descending to a depth of 33 m (110 ft).

The Fleishhacker Pool in San Francisco, California was the largest swimming pool in the United States. Opened on 23 April 1925, it measured 300 by 45 m (980 by 150 ft) and was so large that the lifeguards required kayaks for patrol. It was closed in 1971 due to low patronage.

Dimensions

Most pools in the world are measured in metres, but in the United States pools are almost always measured in feet and yards. In the United Kingdom most pools are in metres, but older pools measured in yards still exist. In the US pools tend to either be 25 yards ( SCY -short course yards), 25 metres ( SCM -short course metres) or 50 metres (long course). US high schools and the NCAA conduct short course (25 yards) competition. There also exist many pools 33⅓ m long, so that 3 lengths = 100 m. This pool dimension is commonly used to accommodate water polo.

USA Swimming (USA-S) swims in both metric and non-metric pools. However, the international standard is metres, and world records are only recognized when swum in 50 m pools (or 25 m for short course). In general, the shorter the pool, the faster the time for the same distance, since the swimmer gains speed from pushing off the wall after each turn at the end of the pool.

Most European pools are between 10 m and 50 m wide.

The depth of a swimming pool depends on the purpose of the pool, and whether it is open to the public or strictly for private use. If it is a private casual, relaxing pool, it may go from 1.0 to 2.0 m (3.3 to 6.6 ft) deep. If it is a public pool designed for diving, it may slope from 3.0 to 5.5 m (9.8 to 18 ft) in the deep end. A children's play pool may be from 0.3 to 1.2 m (1.0 to 4 ft) deep. Most public pools have differing depths to accommodate different swimmer requirements. In many jurisdictions, it is a requirement to show the water depth with clearly marked depths affixed to the pool walls.

Types

Private pools

Private pools are usually smaller than public pools, on average 16 ft × 32 ft (4.9 m × 9.8 m) to 20 ft × 40 ft (6.1 m × 12 m) whereas public pools usually start at 80 ft (24 m). Home pools can be permanently built-in, or be assembled above ground and disassembled after summer. Privately owned outdoor pools in backyards or gardens started to proliferate in the 1950s in regions with warm summer climates, particularly in the United States. In some warm-weather US locations, such as Florida, California, and Arizona, home pools are so common that it is rare to find a new house being built without a pool being considered in the design.

Private pools are increasingly a feature of homes in greater latitudes. For example, in London many larger homes are now refurbished with indoor pools, usually in the basement or in a conservatory. In some European cities, including Munich, it is relatively common for people living in older properties to convert existing internal motorcar garages into indoor pool areas.

Construction methods for private pools vary greatly. The main types of in-ground pools are concrete, vinyl liner, and fiberglass. Above-ground pools (also called "on-ground pools") are usually cheaper to build. They are especially popular in places where ground freezing makes excavation diff

Amazon.com: PUR PBSS Push-Button Refrigerator Ice and Water Filter ...

This item: PUR PBSS Push-Button Refrigerator Ice and ... PUR QTSS Whirlpool Quarter Turn Refrigerator Ice and Water Filter Cartridge

...

4396510 Whirlpool Refrigerator Water Filter Only $31.95

4396510 Whirlpool Refrigerator Water Filter ... L500 for filter model WF-L500 Replacement Cartridge NLC250 for filter model WF-NLC250; The 4396510 Whirlpool refrigerator water ...

...

Whirlpool Refrigerator Water Filters

Whirlpool 4373529 Water Filter Cartridge (4373529) The Whirlpool 4373529 Water Filter Cartridge is the replacement cartridge for your Whirlpool Water Filtration System.

...

Amazon.com: PUR QTSS Whirlpool Quarter Turn Refrigerator Ice and Water ...

Amazon.com: PUR QTSS Whirlpool Quarter Turn Refrigerator Ice and Water Filter Cartridge: Home Improvement

...

Whirlpool Refrigerator Water Filter Cartridge - Filter Value

View Filter Value's wide selection of Whirlpool Refrigerator Water Filter Cartridges.

...

8171413 KitchenAid/Whirlpool Water Filter Whirlpool Interior Turn ...

Whirlpool Interior Turn Water Filter Cartridge 8171413 ... Part Number: 8171413: Manufacturer: Whirlpool: Availability: Ships today: Price:

...

vPOST by SingPost: Tools & Hardware: PUR QTSS Whirlpool Quarter Turn ...

PUR QTSS Whirlpool Quarter Turn Refrigerator Ice and Water Filter Cartridge - Pur - Tools & Hardware - vPOST your USA online eshopping buddy

...

Whirlpool/Kenmore Refrigerator Water Filter Cartridge New Part Number ...

This Whirlpool/Kenmore Refrigerator Water Filter Cartridge Fits Whirlpool, Kenmore and Kitchen Aid Refrigerators. That Have The Filter That

...

4396508, 4392922, 4396510, 8171413 and 8191417 Whirlpool Refrigerator ...

Whirlpool recommends replacing it every 6 months as well. 8171413. This water filter (8171413) cartridge is the replacement for part number ...

...

Whirlpool - WaterFilters.NET - Water Filter Information Forums

Whirlpool - Please use this forum to ask specific questions about Whirlpool brand replacement water filters. ... refrigerater replacement cartridge

...