[ArrogantBustard]

They're propane powered ... a gas leak could start a fire leading to a rupture of the propane tank, followed by a fuel-air explosion.

That would be bad.

[Arthalion]

Yep, I watched a forklift detonate once after an accident left it in the middle of a burning pile of pallets. They got us all WAY back, but the blast was still pretty impressive when that baby went up...and we were OUTSIDE. I can't imagine how powerful that blast must have been in a confined indoor space.

Propane/LNG explosions are nothing to laugh at.

[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?

[Rakkasan1]

the exposed tank on the old-school Zambonis always reminded
me of a big keg of beer.
They explode real good-like a BBQ grill.Don't ask me how I know this.