[Nevadaref]

Originally Posted by Jurassic Referee

After being seatbelted, a coach can legally stand:
1) during a timeout or intermission.
2) to spontaneously react to an outstanding play by a team member, but he/she must immediately sit back down.
3) To request a timeout or to signal one of his players to call a TO.
4) to replace a disqualified player.
5) to go to the scorer's table for a correctable error or scoring or timing mistake

That's it.

Rule 10-5NOTES1 is the rules reference.