Sport Week: Classification in swimming

Swimmers compete in three impairment groups: physical, visual and intellectual. 19 Apr 2016
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Editor’s note: Each sport on the Rio 2016 Paralympic programme will have a dedicated week of featured content published on Every week a new sport will be featured and the series will run until September’s Games, helping the public understand more about the 22 sports being contested in Rio.


In IPC Swimming, athletes are grouped by the degree of activity limitation resulting from an impairment. These groups are called ‘sport classes.’ The process of classification determines which athletes are eligible to compete and how athletes are grouped together for competition.


IPC Swimming caters for three impairment groups - physical, visual and intellectual.


Sport classes


The sport class names in swimming consist of a prefix “S” or “SB” and followed by a number. The prefixes stand for the strokes, and the number indicates the sport classes.


The prefixes stand for:

•S: freestyle, butterfly and backstroke events

•SB: breaststroke

•SM: individual medley. The prefix “SM” is given to athletes competing in individual medley events. It is not a sports class, but an entry index, and calculated as (3xS + SB)/4. For classes S1-4 who have a three-discipline medley, the formula is (2S + SB)/3).


Sport classes S1-S10 - physical impairment

There are 10 different sport classes for athletes with physical impairment, numbered 1-10. A lower number indicates a more severe activity limitation than a higher number.

Athletes with different impairments compete against each other, because sport classes are allocated based on the impact the impairment has on swimming, rather than on the impairment itself.


To evaluate the impact of impairments on swimming, classifiers assess all functional body structures using a point system and ask the athlete to complete a water assessment. The total number of points then determines the athlete’s S and SB sport classes. Due to the different demands of S and SB events, swimmers are often allocated different S and SB sport classes.


The SM sport class is calculated from the S and SB sport class.


The following are general examples of impairments and resulting functional abilities described in each sport class profiles. The below combinations of S and SB sport classes are the most common combinations, but it is possible that that athlete has another combination of sport classes, for example S7 and SB7.

S1 SB1

Swimmers in this sport class have a significant loss of muscle power or control in legs, arms and hands. Some athletes also have limited trunk control. This may be caused by tetraplegia, for example. Swimmers in this class usually use a wheelchair in daily life.

S2 SB1

Swimmers in this sport class mainly rely on their arms for swimming. Their hand, trunk and leg function is limited due to tetraplegia or co-ordination problems, for example.


S3 SB2

This sport class includes athletes with amputations of both arms and legs. Swimmers with reasonable arm strokes but no use of their legs or trunk and swimmers with severe co-ordination problems in all limbs are also included in this sport class.

S4 SB3

Swimmers who can use their arms and have fair function in their hands, but who cannot use their trunk or legs would swim in this sport class. Athletes with amputations of three limbs could also swim in this sport class.

S5 SB4

Swimmers with short stature and an additional impairment, with loss of control over one side of their body (hemiplegia) or with paraplegia compete in this sport class.

S6 SB5

This sport class includes swimmers with short stature or amputations of both arms, or moderate co-ordination problems on one side of their body, for example.

S7 SB6

This sport class is designated for athletes with one leg and one arm amputation on opposite sides, or a paralysis of one arm and one leg on the same side.

Moreover, swimmers with full control over arms and trunk and some leg function can compete in this class.

S8 SB7

Swimmers who have an amputation of one arm are eligible to compete in this sport class. Also, athletes with significant restrictions across hip, knee and ankle joints could compete in this sport class.

S9 SB8

Athletes in this sport class, for example, swim with joint restrictions in one leg or with double below-the-knee amputations.

S10 SB9

This class describes minimal physical impairments of eligible swimmers. These include the loss of one hand or a movement restriction in one hip joint.


Sport classes S/SB11-13 - visual impairment


Athletes with a visual impairment compete in three sport classes from S/SB11 to S/SB13.

S/SB11: These athletes have a very low visual acuity and/ or no light perception.

S/SB12: Athletes have a higher visual acuity than athletes competing in the S/SB11 sport class and/ or a visual field of less than 5 degrees radius.

S/SB13: Athletes have the least severe visual impairment eligible for Paralympic sport. They have the highest visual acuity and/or a visual field of less than 20 degrees radius.

In order to ensure a fair competition, athletes in the S/SB11 sport class are required to wear blackened goggles. To ensure safety, all S/SB11 swimmers must use a tapper, but swimmers in the S/SB12 and S/SB13 sport classes may choose whether or not to use one.

Sport classes S/SB14 - intellectual impairment

S14 swimmers have an intellectual impairment, which typically leads to the athletes having difficulties with regards to pattern recognition, sequencing, and memory, or having a slower reaction time, which impact on sport performance in general. Moreover, S14 swimmers show a higher number of strokes relative to their speed than able-bodied high performance swimmers.


Helpful links

IPC Swimming’s website.

Guide to classification in summer Paralympic sports.



Sport fans from around the world can now buy their Paralympic tickets for Rio 2016 from authorised ticket resellers (ATRs).

The IPC’s Global ATR is Jet Set Sports, and Rio 2016 tickets and packages can be purchased on the CoSport website.

Residents of Brazil can buy 2016 Paralympics tickets directly from the Rio 2016 website.