I’m no scientist, but from my days of shipboard firefighting we were taught that freon is heavier that the atmosphere therefor sank to the decks. We had extensive atmospheric tests to conduct to ensure the low-level air was safe to breath.
I think you are correct. But I only do it because it annoys the eco-weinies. They think it puts holes in the ozone layer or some such.
PS - Thank you for your service to our country. My father is a retired USN Senior Chief. NCOs run the Navy.