Long course
An Olympic-size swimming pool is the type of swimming pool used in the Olympic Games, where the race course is 50 metres (164.0 ft) in length. This is typically referred to as "long course", distinguishing it from "short course" which applies to competitions in pools that are 25 metres (82.0 ft) in length. If touch panels are used in competition, then the distance between touch panels should be either 25 or 50 metres to qualify for FINA recognition. This means that Olympic pools are generally oversized, to accommodate touch panels used in competition. An Olympic-size swimming pool is used as a colloquial unit of volume, to make approximate comparisons to similarly sized objects or volumes. It is not a specific definition, as there is no official limit on the depth of an Olympic pool. The value has an order of magnitude of 1 megaliter (ML).
FINA specifications for an Olympic-size pool are as follows:
2,500 m3 (88,000 cu ft) in cubic units.
About 2 acre-feet.
There must be two spaces 2.5 m (8 ft 2 in) wide outside lanes 1 and 8 (in effect, two empty lanes). The length of 50 metres (164 ft) must be between the touch pads at the end of each lane, if they are used. If starting blocks are used, then there must be a minimum depth of 1.35 metres (4.4 ft) from between 1.0 metre (3 ft) from the end of the pool to at least 6.0 metres (20 ft) from the end of the pool. At all other points, the minimum depth is 1.0 metre (3 ft). If the pool is used for Olympic Games or World Championships, then the minimum depth is increased to 2.0 metres (7 ft).
At FINA's 2009 Congress, rules were approved for 10-lane courses for competition, as an alternative to the more traditional 8-lane course.
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