It is interesting to discover others sense of smell. Have a friend who runs those propane radiant heaters in his garage claiming they don't smell, yet when guests enter his house they all say the smell will make you sick instantly.
Doubt there is anything that doesn't give off a scent and the fragrance will linger in the air long after the trains are done operating. Run 4 MTH diesel for a few hours and you don't need air fresheners anymore. Maybe you just need a bigger cfm exhaust fan! Good luck!!