I don't know about FIDE, but the USCF has this rule:
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Hi all,
    I've been reading "Counterplay", an anthroplogist's attempt to explain why we put so much time and energy into chess. Accepting that a lot of us put in a lot of time and energy, why do we put up with poor behaviour ? I believe all players know how to behave. It's not too much more than being polite and providing to other players the conditions you would like. However, when people do talk, crunch crisps or peanuts or stand very close to the board, I am amazed at how tolerant we are. In my experience there is no relationship to playing strength or length of time playing the game. Some clubs seem worse than others. Most tournaments are good but some organisers / arbiters / controllers give up on attempting to maintain quiet conditions for example. I'm grateful to the club I started in where the attitude shown by players at the board, away from the board when others were in play and also to a beginner, set a good example to me. Further, an example was displayed in taking the initiative in correcting people who were behaving inconsiderately. I'm ready to say something when it's needed but cannot understand the players / clubs / tournament officials who let these things happen, sometimes on an on-going basis.

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