The Federation Internationale de Natation (FINA) regulates Olympic water polo for both men and women. They keep things simple, by specifying only the most basic characteristics for the ball – it must be round and waterproof, without straps or greasy coverings. With women able compete in the Olympics beginning in 2000, a slightly smaller ball was introduced into the games.
WP 3 THE BALL
WP 3.1 The ball shall be round and shall have an air chamber with a self-closing valve. It shall be waterproof, without external strapping or any covering of grease or similar substance.
WP 3.2 The weight of the ball shall be not less than 400 grammes and not more than 450 grammes.
WP 3.3 For games played by men, the circumference of the ball shall be not less than 0.68 metres and not more than 0.71 metres, and its pressure shall be 90-97 kPa (kilo Pascal’s)(13-14 pounds per square inch atmospheric).
WP 3.4 For games played by women, the circumference of the ball shall be not less than 0.65 metres and not more than 0.67 metres, and its pressure shall be 83-90 (kilo Pascal’s) (12-13 pounds per square inch atmospheric).
Federation Internationale de Natation – www.fina.org
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