The crew state is triggered automatically by the game. For example, if a line like this one is triggered:
Code:
Dialog:PlaySound( "ChiefEngineer_slash_", "MC_CR_CHIEF_01_A", 0 );
the game will automatically look for a speech file with that name in all three folders - Normal, Tension and Whisper. If the assigned filename is found only in one of those folders, it will use it for all states.