A Unique Smell
Those who work on a submarine live in a closed environment where their air is constantly being recycled. This means that once the hatch is sealed, all you would smell is a combination of oil, amine, and body odors.
Amine is a kind of chemical that’s used to remove carbon dioxide from the air. While it is quite helpful and, in essence, allows these submarines to move underwater for lengthy periods of time, it is rather odorous.