The starting platform is used by athletes at the beginning of the competition, and there are eight platforms. The table top is square, at least 50 cm long, with the front edge 50-75 cm higher than the water surface. The table top inclines forward no more than 10 degree, and the surface must be non-slip. Under the starting platform, there is a handshaker for backstroke, which is horizontal and vertical. The grip is 30-60 cm above the water surface and parallel to the pool wall.
The lane dividing line is a sign line for distinguishing lanes, which is formed by connecting single buoys with a diameter of 5- 1 1cm (the colors of all buoys beyond 5m at both ends of the lane dividing line must be different from others). There are 9 lanes, each lane is 2.50m wide, and 1 and 9 lanes are at least 50m away from the pool edge. The line also has the functions of smoothing waves and eliminating waves. The number of lanes is arranged from right to left at the end of the starting platform facing the swimming pool.
The recall line is a rope line placed on a fixed column at a distance of15m from the starting end of the swimming pool, which is more than1.2m from the water surface. It can be quickly put into the water to remember the first runner in the competition.
The backstroke turning sign line is a flag rope composed of several red and yellow flags. The rope passes through the swimming pool and is placed on a fixed post 5 meters away from the pool end, which is more than 1.80 meters above the water surface.
Modern competitive swimming rules stipulate that if an athlete starts first in a competition, the starter will recall him within 1 time and give him a warning. The second time, no matter which athlete starts first, he will be fined and disqualified. If the gunshots have already sounded, they will not be recalled and will be punished after the group match. Athletes are not allowed to use or wear any equipment (except goggles) that is beneficial to their speed and buoyancy in the competition. When arranging the lanes in the competition, the athletes or relay teams with the best performance in the same group are ranked in the fourth lane, the second best fifth lane and the third lane in turn, and the rest are ranked in the sixth, second, seventh, 1 and eighth lanes in turn. The same performance will be decided by drawing lots. The finals of the Olympic Games and other major swimming competitions are divided into two groups, A and B (the swimming lanes are arranged as above). Group A decides 1-8, and Group B decides 9- 16. If the final score of Group B exceeds that of Group A, the highest ranking of Group B is still the ninth, because its results in the preliminaries and semi-finals can only be determined by participating in the finals of Group B.