Article 13: The role of the arbiter (see Preface)
13.1 The arbiter shall see that the Laws of Chess are strictly observed.
13.2 The arbiter shall act in the best interest of the competition. He should ensure that a good playing environment is maintained and that the players are not disturbed. He shall supervise the progress of the competition.
The arbiter shall observe the games, especially when the players are short
of time, enforce decisions he has made and impose penalties on
13.6 The arbiter must not intervene in a game except in cases described by the Laws of Chess. He shall not indicate the number of moves made, except in applying Article 8.5, when at least one player has used all his time. The arbiter shall refrain from informing a player that his opponent has completed a move.
13.7 Spectators and players in other games are not to speak about or otherwise interfere in a game. If necessary, the arbiter may expel offenders from the playing venue.