Hazardous lack of common sense with relevant results:
This video is really rather stupid, but illustrates what happens when hot melty thing (In this case, thermite) meets flammable compressed liquid gassy thing (In this case a propane cylinder).
<idiot>
http://www.ebaumsworld.com/video/watch/897350/
</idiot>
It doesn’t actually explode, due to lack of oxidising agent in the tank - but makes a nice pretty tall flame that would probably make life on deck uncomfortable enough.