30. Water Polo
It is recommended, but not required, that clocks used in conducting water polo contests be visible to the participants.
3001. OFFICIAL NATIONAL FEDERATION AUTHENTICATION MARK
Beginning with the 2000-2001 school year, only balls with the National Federation authentication mark shall be used in the sports of baseball, basketball, field hockey, football, lacrosse, soccer, volleyball and water polo (Approved February 1999 Federated Council, revised to include lacrosse November 2000 Federated Council).