For extreme cases:
If you're at a dock
, you get off the boat and call the fire department. They will run a hose in from a high volume blower.
If out on the water
, DO NOT flip any switches. Open the hatches while not
dragging your feet and hopefully there is a breeze. Propane
will dissipate with enough circulation. Hopefully your sailing. If motoring a diesel
, just keep going towards land/port, and stay away from the hatches/entry.
It takes a certain amount of gas/air ratio for an explosion. Not enough gas, or not enough air/oxy. But boats do have the right conditions.
One can actually take a bottle and fill it with propane
and drop a match in it, and the match will go out. BUT DO NOT TRY THIS AT HOME! It's an example demo I learned in "Confined Spaces Training".