Referees
Refereeing the game are two (or three) water referees (i.e. in the pool with full snorkelling gear, and wearing a distinctive cap, gloves and t-shirt) to observe and referee play at the pool bottom, and one or more poolside deck referees to track time (both in the period and for each ejected player), maintain the score, and call fouls (such as excessive number of players in play, failure to start a point from the end of the playing area, or another foul capable of being committed at or noticed at the surface). The deck (chief) referee responds to hand signals given by the water referees to start and stop play, including after an interruption such as a foul or time-out.
The Official Rules which are available for download in PDF form without charge and define (with illustrations) a valid goal, the fouls and signals, and the dimensions of the playing area, sticks, and goals.
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