Of note is "6-G.Operation Through All Tunnels-Windows, vestibule doors, connecting doors and other openings must be closed and air conditioning apparatus shut off on all passenger trains moving through tunnels"
This is still SOP for traversing the Moffat. I ride Amtrak's CZ back and forth between DEN and GJT a fair number of times each year and the Conductors always make an all train announcement asking people to NOT move between cars but remain where they are during our passage.
Rich