Warnings are given to players and teams to let them know that if the foul warned against is done again, the referee will begin to give time penalties. A warning is signaled with the thumb extended to the side from a fist. An individual warning is indicated by the warning signal pointed at that player. A team warning is signaled by sweeping the signal across the surface of the water, indicating the entire team. The referee will also signal which foul they are warning the team or player to avoid.
The referee calls a barging foul and delivers an individual warning.