[Old Professer]

If the tank ruptured the propane would merely turn into a blow torch; if the tank exploded as you say it would have to occur after sufficient heating to rupture the tank which would still be a minor explosive force but would send the vaporizing, burning fuel to a great distance but would not have a strong blast wall.

What would account for a strong blast wall would be a leak in the enclosed storage area from the propane tank or fittings allowing a build up of heavier than air gasses and then ignition which would blow the doors off and knock nearby objects to the floor.

The only question in my mind is what source provided the ignition?

[ArrogantBustard]

The usual mechanism for a liquified gas tank to explode is the BLEVE, in which external fire heats the tank, raising internal pressure until the tank fails catastrophically.

That usually takes time ... The sequence of events here is less than clear to me.

[jjmcgo]

Ol' Joe havin' a butt after cleaning the ice?

[JLO]

"What would account for a strong blast wall would be a leak in the enclosed storage area from the propane tank or fittings allowing a build up of heavier than air gasses and then ignition which would blow the doors off and knock nearby objects to the floor.

The only question in my mind is what source provided the ignition?"
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Local news this morning said it was a water heater pilot light.