Simultaneous exhibition rules There are the FIDE Rules for Chess. This for different types of chess. Are there also official rules for Simultaneous exhibition chess? Where can I find them?
I don't think FIDE would be involved in regulating such events because they are not rated.
I found this interesting PDF with some notes, although I think they could be improved. For example, it is not clear if the player loses the game after three passes.


The exhibitor plays the white pieces on each board.
Do not touch any chessman until the exhibitor arrives at your board. When the exhibitor is standing in front of your board, make your move (within 5 seconds) while the exhibitor is observing. The exhibitor will make a move on your board before going on to the next board.
Participants, but not the exhibitor, must abide by the touch move rule. The exhibitor’s move is not final until he or she touches a piece on the next board.
Each player is allowed three passes when the exhibitor arrives at his or her board. Using a pass means that the exhibitor will skip your board, but you will need to make a move (or use another pass) when the exhibitor comes back after visiting the other boards.
Participants may not receive assistance from other players or bystanders during their games.
Exception: participants may sign up as a pair and play on one board.
Participants must take notation.
If the exhibitor has any other rules, those will be announced at the start of the exhibition.


Source:

Simul Rules