It is pretty easy to mistakenly have propane coming from the stove
by just user error/inattention. I've done it. Luckily noticed before
an explosion. The incident was caused by something in the camper
falling against and pushing on the stove knob in such a way that it
opened and kept the gas open. Forgot exactly what fell. The incident
was several years ago. But afterwards I made sure to check propane
is shutoff when not in use.

Over the years Westfalia has tried to improve the "foolproofness" of
the stove. On my '94 Westy the stove knobs are on top of the stove.
That way, as long as one closes the lid after using the stove nothing
can fall onto the knobs as happened in my Vanagon Westy.

Late Vanagon Westys have the flame sensor shutoff. However in the
low probability event (but with hundreds of thousands of campers
worldwide likely to happen sooner or later), that something both
hits the knob and hold/jams it in the turned and pushed in position
the flame sensor is bypassed.

My '82 westy stove doesn't have a flame sensor. Knobs are secured by
requiring a push and turn operation as in the later camper, but gas
will stay on without a flame. (Fridge thankfully has the flame sensor)

Martin
--
Martin Jagersand
University of Alberta
http://www.cs.ualberta.ca/~jag/