I took fishing trips for many years. The cabins had propane fuels tanks for the water heater, refrigerator and stove. We were always told to keep several windows cracked at all times since there were no ventilation vents of significance.
I’m uneasy about propane because it sinks to the low spots.
“Natural gas tends to rise into the air and scatter, whereas propane tends to collect in low-lying locations like basements, crawl spaces, and ditches.”
Natural gas wants to escape and get outside into the wind, while propane will puddle and set up an explosive environment.