Thou shalt use only approved, clearly-marked containers to store thy inflammable liquids, and thou shalt use those containers to store only the liquids for which they are marked. Thou shalt never use gasoline cans to store the muck thou hast flushed out of the bottom of the diesel storage tank.
An thou fail to obey this rule, thou art not permitted surprise when said muck finds its way into a lawn-mower's gas tank. (Seriously! I'm actually supposed to smell
it before I start pouring?!?)
Also, for the benefit of the Sky Pirates:
Always remember, it's pillage, then burn!