Those rail cars have a pressure relief device on them. That is probably what the "steam" is. I am guessing the set pressure of the relief valve is probably around 75 to 100psi
Mineral Spirits have a flash point of around 109degrees F. the auto ignition temp is around 473 degrees F. As long as the relief valve functions there should be little chance of a "BLEVE" or Boiling Liquid Expanding Vapor Explosion. If that relief valve fails things will get real exciting real fast!!!
Regards
alfa6 ;>}
Oh, man! Voice of information speaks and ruins the excitement. I love FR!! People are so smart about the strangest details! :o)