Para-swimming classification

Para-swimming classification is a function-based classification system designed to allow for fair competition in disability swimming. The classes are prefixed with "S" for freestyle, butterfly and backstroke events, "SB" for breaststroke and "SM" for individual medley events. Swimmers with physical disabilities are divided into ten classes based on their degree of functional disability. Those with visual impairments are placed in three additional classes. A final class, S14, is reserved for swimmers with intellectual disabilities.

Swimming was one of the first organised sports for people with disabilities, and was contested at the first Summer Paralympics in 1960. Both the rules for the sport and approval of classifications were the responsibility of the Fédération International de Natation Amateur (FINA) until 1992, when the International Paralympic Committee took over the governance of classification. As of 2012, people with visual, physical and intellectual disabilities are eligible to compete in the sport. The classification system was originally based on medical criteria, but has since moved to one largely based on functional disability to make para-swimming more competitive. The sport is moving towards an evidence-based classification system.

Para-swimming classification is based on a system in which functional criteria are assessed. Athletes who have different physical disabilities may compete in the same class so long as their functional impairments are similar. In swimming, amputations of the arms below the elbow have a significant impact on functional ability. As a result, swimming classifications differ from athletics classifications. Swimmers are divided into ten classes based on degree of functional disability: S1, S2, S3, S4, S5, S6, S7, S8, S9 and S10. The most severely affected are in class S1; these swimmers normally use wheelchairs outside of the pool. Classes are prefixed with the letter "S" for freestyle, butterfly and backstroke events, while those prefixed with "SB" are for breaststroke, and those with "SM" for individual medley events. This is because different strokes require the use of different muscle groups. In the case of the breaststroke, for example, the hand and the hip play a crucial role. Because of this, a swimmer may compete in one class for one stroke and a different class for another. It also means that swimmers with cerebral palsy, spinal cord injuries and limb deficiencies may compete against each other. For the individual medley, the class assigned is the mean average of the classes assigned for each individual stroke (rounded to the nearest whole number with .5 rounding up).

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